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Socio-Economic Impacts of Controlling Melaleuca in South Florida

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Title:
Socio-Economic Impacts of Controlling Melaleuca in South Florida
Creator:
FINN, KATHERINE
Copyright Date:
2008

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Subjects / Keywords:
Agricultural land ( jstor )
Agriculture ( jstor )
Cost control ( jstor )
Cost estimates ( jstor )
Herbicides ( jstor )
Infestation ( jstor )
Information professionals ( jstor )
Land management ( jstor )
Land surveying ( jstor )
Land use ( jstor )
Miami metropolitan area ( local )

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Source Institution:
University of Florida
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University of Florida
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Copyright Katherine Finn. Permission granted to University of Florida to digitize and display this item for non-profit research and educational purposes. Any reuse of this item in excess of fair use or other copyright exemptions requires permission of the copyright holder.
Embargo Date:
8/31/2006
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649814506 ( OCLC )

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Full Text











SOCIO-ECONOMIC IMPACTS


OF CONTROLLING 2elaleuca IN SOUTH
FLORIDA


By

KATHERINE FINN


A THESIS PRESENTED TO THE GRADUATE SCHOOL
OF THE UNIVERSITY OF FLORIDA IN PARTIAL FULFILLMENT
OF THE REQUIREMENTS FOR THE DEGREE OF
MASTER OF SCIENCE

UNIVERSITY OF FLORIDA


2006


































Copyright 2006

by

Katherine Finn




























For Jeffrey
















ACKNOWLEDGMENTS

I would like to start off by thanking my husband Jeffrey Finn who has traveled this

journey with me and been the best partner I could have ever hoped for. I especially thank

him for the encouragement and perspective that he has offered me along the way.

I wish to express eternal thanks to my Mom, Gena Carte, for her never ending

support and for always telling me that I can do whatever I set my mind to, even when it

feels like it is impossible.

I wish to express my deepest gratitude to my Dad, Jerry Carter, for showing me the

value of hard work, fostering my appreciation for nature, and for teaching me to hunt and

fish better than most men.

My deepest gratitude goes out to my committee members Dr. Alan Hodges, Dr.

Donna Lee, and Dr. Mike Olexa for their guidance along the way. I am especially

grateful to Dr. Hodges who worked with me on a day to day basis and taught me so

much. His patience and dedication are appreciated more than he will ever know.

I wish to offer special thanks to the USDA-ARS for funding this research. I would

like to express my gratitude to Francois Laroche of the South Florida Water Management

District and the members of the TAME Melaleuca team, especially Cressida Silvers, Paul

Pratt, and Amy Ferriter for always being willing to answer "just one more question."

Many thanks go to Sharon Wallace of the South Florida Water Management District,

Debbie Gillet of the Southwest Florida Water Management District, Chris Wassil and

Gary Lewis with the Florida Division of Forestry, and Gail Baxley with the Florida










Department of Environmental Protection' s Office of Park Planning for sharing their data,

insight, and experiences with me. Thanks go to Carol Fountain for all of her formatting

expertise.

I would like to express my thanks to all of the friends I have made in graduate

school. They are the reason I will look back on this whole experience and have pleasant

memories filled with smiles and laughter. Thanks go to the best study group around,

Erika Knight, Jamille Palacios, Anne Jones, and Jennie Varela; the first year core would

have been impossible without them. I am especially grateful for the fact that at the first

day of orientation I sat next to Erika Knight and struck up a conversation; her friendship

has been priceless. Special thanks go to Damian Adams for being a great colleague and

wonderful friend. Thanks go to comedians Justin Taylor (GO RACERS!i) and Athur

Mabiso for always offering an easy laugh and "Respect." Thanks go to Annie

Hildebrand for offering me big beautiful smiles when I needed them the most.

Special thanks go to my friend Beth-Anne Blue for all of her wisdom, guidance,

and s port and es ecially for reminding me that I could do this.

I would like to acknowledge the close family members who are no longer here with

me to share in the j oy of this accomplishment: my Grandparents Pepa and Grammie

(Red and Mary) Carter, Gov (Gran-Daddy Victor B. Carte, Jr.), and step-father Scott

Whidden. I wish to thank them for all of the love and support they offered during their

time here.

Last, but certainly not least, I offer my thanks to God, for with Him everything is

possible.



















TABLE OF CONTENTS


page

ACKNOWLEDGMENT S .............. .................... iv


LI ST OF T ABLE S ................. ................. ix......... ...


LI ST OF FIGURE S .............. .................... xi


AB STRAC T ................ .............. xii


CHAPTER


1 INTRODUCTION ................. ...............1.......... ......


Origins, Introduction, and Invasion ................. ...............2................
The War Against M~elaleuca ............ ..... ._ ...............3...
Problem Statement ............_....... .__ ...............5....
Public Lands vs. Private Lands................ ...............6.
Hypotheses & Parameters Estimated ................. ...............7................
Research Objectives............... ...............

2 LITERATURE REVIEW .............. ...............9.....


Introduction to Benefit-Cost Analysis ................. ...............9................
Formal Theoretical Framework Behind BCA ................. ............... ......... ...11
Benefit Cost Analysis and Social Welfare Theory .......... ................ ...............13
Individual Welfare Changes ................ ...............13........... ....
Social Welfare Changes .............. ...............16....
Benefit-Cost Analysis in Practice............... ...............17
Use of Mail Surveys ..................... ........... ...........1
The Contingent Valuation Method (CVM) .................. ...............21..
Previous Research on the Economic Impacts of Melaleuca .............. ...............25

3 SURVEY DESIGN, CONTENT, AND ADMINISTRATION .............. ...............27


Survey M ethod s .................. .... .......... .. .. ........ ............ 2
Survey Study Area, Target Populations, and Sampling .............. ....................2
Survey Content .............. ...............28....
Residential Survey ................... ...............29.......... ......
Professional Land Manager Survey ................. ...............31................
Survey Administration............... .............3












4 SURVEY RESULT S .............. ...............34....


Results for Professional Managers .............. ...............34....
Land Ownership Status............... ...............34.
Land U se................ .. ... .. ............3
Factors Affecting Land Management ................. ............. ............... 36. ....
Area Occupied By Invasive Plants and Area Treated .............. ....................3
Methods Used for Treating M~elaleuca .............__..... ........._........41
Barriers to Controlling M~elaleuca ......................... .............__ ............4
Sources and Usefulness of Information for M~elaleuca Control.............._.._.......47
Costs for M~elaleuca Control .......__ ......... __ .........___.....__......50

Impacts of2 ~elaleuca ................. ...... .... .... ... ..... .........5
Annual Income or Budget and Comparison of Reported Melaleuca Control
Expenses .............. ...............54....
Results for Residents .............. ...............56....
Invasive Plant Awareness............... ...............5
Amount of Melaleuca on Property ............_......__ ....__ ...........5
Use of Control Methods for M~elaleuca ......____ ........ .........._.......5
Barriers to Controlling M~elaleuca .....__.....___ ..........._ ............5
Information Sources for M~elaleuca Control ......____ ...... .. ...............59

Expenses for M~elaleuca Control ........._..._......__ ....__ ............6
Impacts on Property Values............... ......... .... ..........6
Willingness to Pay for M~elaleuca Removal/Eradication .............. ........._.....61
Impacts of Melaleuca on Outdoor Enj oyment ........._._..... .... ....___ ..............62
Willingness to Pay to Reduce M~elaleuca in Outdoor Activity Areas ........._......63
Respondent Demographics ................. ....___ ....___ .............6

5 BENEFIT COST ANALYSIS ........._... .....___ ...............67...


Calculation of Benefits .............. ...............68....

Ecosystem Benefits ................. .... ..... .............7
Agricultural Land Productivity Benefits .............. ...............73....
Agricultural Land Market Value Benefits .....__.___ ..... ... ._ ........._.... ..74
Recreation Benefits .............. ...............74....
Additional Benefits ................. ...............76........... ....
Calculation of Costs .................. ............. ...............77......
Calculation of the Benefit-Cost Ratio ................. ...............80........... ...


6 SUMMARY AND CONCLUSIONS ................ ...............83................


Sum m ary ................. .. ... .. ....... ... ........ ...... .........83
Conclusions, Implications, and Policy Recommendations ................. ................ ...85
Recommendations for Future Work .............. ...............88....











APPENDIX

A MELALEUCA MANAGEMENT SURVEY OF PROFESSIONAL LAND
M ANAGERS ................. ...............90.......... ......

B MELALEUCA MANAGEMENT SURVEY OF RESIDENTIAL PROPERTIES ...99

LIST OF REFERENCE S ................. ...............113................

BIOGRAPHICAL SKETCH ................. ...............117......... ......


















LIST OF TABLES


Table pg

4-1 Land area managed by surveyed professional land managers in Florida. ................35

4-2 Land use types and areas managed by professional land managers in Florida. .......36

4-3 Factors influencing management decisions by professional land managers in
Florida. ............. ...............38.....

4-4 Land area infested with and treated for invasive species by professional
managers in Florida ................. ...............41........... ....

4-5 Methods used for treatment of2~elaleuca by professional land managers in
Florida. ............. ...............43.....

4-6 Number of professional managers using various control methods and area of
M~elaleuca treated in Florida, 2003 and 1990-2003 .......____ ...... ..__ ............44

4-7 Intentions for future use of various M~elaleuca control methods by professional
managers in Florida. .............. ...............45....

4-8 Requests for more information on M~elaleuca control methods by professional
managers in Florida. .............. ...............45....

4-9 Barriers to controlling Melaleuca by professional managers. .............. ..............47

4-10 Information sources and types of media used by professional land managers in
Florida. ............. ...............48.....

4-11 Usefulness of information received by professional land managers in South
Florida. ............. ...............50.....

4-12 Costs for M~elaleuca control reported by professional land managers in Florida,
2003 ....._..__ ........__ ....__ ....__ ....__ ....__ ..............51

4-13 Expenses for special equipment for M~elaleuca control by professional managers
in Florida. ............. ...............5 1....

4-14 M~elaleuca treatment cost trends reported by professional land managers in
Florida. ............. ...............52.....











4-15 Negative impacts of2~elaleuca reported by professional land managers in
Florida. ............. ...............53.....

4-16 Reduction in utility due to M~elaleuca infestation reported by professional land
managers. ........... ..... ._ ...............54...

4-17 Annual income or budget for land management by south Florida professional
managers, 2003 ........... .......__ ...............55...

4-18 Awareness of 2elaleuca and invasive plants by Florida residents. .......................56

4-19 Amount of Melaleuca on property of Florida residents .................... ...............5

4-20 Methods used for M~elaleuca control by Florida residents, and interest in more
information about control methods. ............. ...............57.....

4-21 Barriers to controlling Melaleuca by Florida residents............_.._ ..........___.....58

4-22 Sources of information on M~elaleuca received by Florida residents. ....................59

4-23 Expenses for Melaleuca control by Florida residents, 2003. ............. ...............60

4-24 Negative effect of M~elaleuca on property value of Florida residents.....................6 1

4-25 Willingness to pay for removal of2~elaleuca from property by Florida residents..62

4-26 Days of annual outdoor recreation activity reported by south Florida residents,
2003 ........._.._. ....._... ........_. ....._. ...._... ....._. .........._.63

4-27 Effect of2~elaleuca on outdoor enj oyment by Florida residents. ........._................63

4-28 Willingness to pay per visit to reduce M~elaleuca in recreational areas by Florida
re sidents ........... ....... __ ...............64..

4-29 Demographics characteristics of surveyed south Florida residents, 2003. ...............66

5-1 Ecosystem Values for Surveyed Land Use Classifications............... .............7

5-2 Average Negative Impact Values for Surveyed Land Use Classifications. .............73

5-3 Total Benefits of2~elaleuca Control in 2003 ........._._ ....... ................77

















LIST OF FIGURES

Figure pg

4-1 Average weighting of factors influencing management by professional land
managers ................. ...............39......_ ._ .....

4-2 Usefulness rating of information sources and media by professional land
managers in Florida ........._ ............ ...............49....
















Abstract of Thesis Presented to the Graduate School
of the University of Florida in Partial Fulfillment of the
Requirements for the Degree of Master of Science

SOCIO-ECONOMIC IMPACTS OF CONTROLLING2~elaleuca INT SOUTH
FLORIDA

By

Katherine Finn

August 2006

Chair: Donna Lee
Major Department: Food and Resource Economics

M~elaleuca quinquenervia, commonly referred to as M~elaleuca, was introduced to

Florida in the late 1800s and has flourished in the state since its introduction. In the late

1980s and early 1990s efforts to eradicate/control M~elaleuca began in earnest. The

Areawide Management Evaluation of2~elaleuca (TAME) program was created

specifically to research and address the problems and unique situations associated with

M~elaleuca control. Public agencies in Florida spent an estimated $25 million on control

efforts from 1989 to 1999 and have succeeded in reducing the area it covers; however,

private landholders have been less aggressive in its removal. Despite the control efforts

on public lands, the lack of treatment on private lands has allowed M~elaleuca to spread in

many areas and resulted in no net loss of the acreage covered.

M~elaleuca causes a reduction in ecological function, agricultural productivity, and

recreational use value of lands occupied. In order to document the current management

and socio-economic impacts of this species, surveys were mailed to 2,000 agricultural










landowners, 285 park/preserve managers, and 5,000 randomly selected residents in the

ten southernmost counties of Florida in 2004.

Survey results revealed that M~elaleuca covered more than 620,000 acres of land

and that professional managers (both park/preserve and agricultural) had treated

approximately 86,731 acres during 2003. A benefit-cost analysis was conducted for the

areas controlled in 2003. The benefits were estimated based on the values for restored

ecological function of agricultural and park/preserve land, agricultural productivity and

market value of agricultural land, the recreational use of park/preserve lands where

M~elaleuca controls had been implemented, and avoidance of costs connected with

M~elaleuca fueled fire control. Total benefits amounted to $23.3 million. The costs were

derived from the residential and professional survey data along with TAME M~elaleuca

program costs which include the costs associated with this research. Total costs

amounted to $13.2 million

The resulting benefit-cost ratio (1.76) indicates that the benefits of2~elaleuca

removal were significantly greater than the costs, and that control efforts provided a net

social benefit to society in the year 2003. Therefore, it is recommended that the policy

stay in effect until the benefits no longer outweigh the costs.















CHAPTER 1
INTTRODUCTION

An invasive species as defined by the 1999 Executive Order 13112 is "an alien

species whose introduction does or is likely to cause economic or environmental harm or

harm to human health." Invasive species have affected many, if not most, countries

around the world in some way. In some cases, alien species are purposefully introduced

for bona fide reasons; case in point, the now infamous Kudzu used for ornamental

purposes, erosion control, and livestock forage. In other situations a species is

inadvertently introduced through increased global travel, such as the Brown Tree Snake's

introduction to Guam. Some alien species are introduced and remain rather innocuous

throughout their lifespan. However, often times they can cause devastating and

irreversible consequences, such as the almost total annihilation of Guam' s songbird

population and Kudzu's prolific spread throughout the Southeast and Hawai'i to now

cover several million acres of land.

Every year, a growing number of individuals make Florida their new home.

However, this phenomenon is not limited to humans. Plants, animals, and pathogens also

find ways to make this accommodating sub-tropical land their home as well. Florida' s

mild winters and warm wet summers are quite hospitable to many different species and

allow non-native residents to become resident aliens. One especially destructive alien

invader that has now become an invasive species is the highly problematic tree

commonly known as M~elaleuca (M~elaleuca quinquenervia).









Origins, Introduction, and Invasion

M~elaleuca also had a rather innocent beginning in Florida. It is thought to have

been introduced in Florida by Royal Palm Nurseries in Manatee County around 1887.

The tree was popularized by nurseries and gained greater recognition due to its ability to

thrive in many environments and rapidly provide shade and windbreaks for home owners

(Serbesoff-King 2003). It was subsequently planted in swampy areas to help dry up the

standing water so developers could build to meet the demand of the booming South

Florida population (Laroche and McKim 2004). This notion has now become the subject

of much debate amongst scholars. While some scientists adhere to the belief that

M~elaleuca consumes more water than native vegetation, others argue that their research

indicates that it does not use any more water than the average plant.

In 1941, Florida populations of2~elaleuca from Lake Okeechobee southward

began to increase as the US Army Corps of Engineers (USACE) planted the trees along

levees and spoil islands for erosion control (Stocker and Sanders 1981). This fast

growing species has now become established, and has spread much more quickly in

Florida than in Australia, and competes with many native plant species (Rayamajhi et al.

2002). Due to its rapid growth and reproduction rates, Melaleuca may completely

dominate landscapes that it invades, thus decreasing biodiversity and precluding the

growth of native vegetation (Schmitz and Hofstetter 1999). Studies show that patches of

M~elaleuca can spread to dominate one square mile of land in only 25 years (Laroche and

Ferriter 1992). M~elaleuca may also increase wildfire danger, because the dense stands

burn with greater intensity making fire control more difficult (Diamond et al. 1991).









The War Against Melaleuca

While this tree has been on Florida soil for more than 100 years, its control was not

seriously pursued in the state until the latel980's. This is due, in part, to the movement

to restore the Everglades. During the 1990's, the framework leading up to the

Comprehensive Everglades Restoration Plan (CERP) began to be developed. After the

foundation was laid by the previous Water Resources Development Acts of 1992 and

1996, President Clinton signed the Water Resources Development Act of 2000, Section

601 which authorized the CERP. When it became clear that invasive species would only

serve to thwart the goals of CERP which are restoring, preserving, and protecting South

Florida's ecosystem, measures were taken to address the growing problem. Specifically,

the M~elaleuca Eradication and Other Exotic Plants proj ect, within the CERP, was

designed to address exotic and invasive species management and control in Southern

Florida (CERP 2004). Recognizing the need to take aggressive action against invasive

species, in 1993 the Florida legislature enacted statutes that require agencies such as the

Florida Department of Environmental Protection Bureau of Invasive Plant Management

(FDEP-BIPM) to investigate methods of control for M~elaleuca and to implement those

control methods within their jurisdiction (FS 369.252). Under current state law it is

illegal to sell, transport, collect, cultivate or possess any plant, including any part or seed

of the species M~elaleuca quinquenervia without a permit from the FDEP or the Florida

Department of Agriculture and Consumer Services (FDACS) (FS 369.251).

In 1997 the legislature directed the Bureau of Invasive Plant Management (BIPM)

to build a program to bring exotic upland species under maintenance control, by enacting

Florida statute 369.22. The statute details that a maintenance control program is "a

method for the control of non-indigenous aquatic plants in which control techniques are









utilized in a coordinated manner on a continuous basis in order to maintain the plant

population at the lowest feasible level as determined by the department" (FS 369.22 p.1).

The 1993 Florida legislature also set aside an annual budget of $1 million to the FDEP

specifically for Melaleuca control. The FDEP took the award from the legislature and

then entered into a cost-sharing program (called the M~elaleuca Program) with the South

Florida Water Management District (SFWMD) in which they match that award dollar for

dollar (BIPM 2003.) The goal of the M~elaleuca program is to control M~elaeluca on all

SFWMD land and to maintain the lowest possible infestation rates while minimizing

impacts to non-target plant species. In order to prevent the wider spread of the plant,

outlying lesser infested areas are treated first according to a quarantine strategy (BIPM

2003). The goal of the FDEP is to reduce infestations of upland invasive exotic plants on

public lands by 25 percent by the year 2010 based on the estimated 1995 level of

infestation of 1.5 million acres (BIPM 2003). It should be noted that this estimated area

is for all upland invasive species and not just M~elaleuca.

Additionally, The Areawide Management Evaluation of Melaleuca (TAME

M~elaleuca or TAME) has been established under the auspices of the USDA Agricultural

Research Service (ARS) Areawide Pest Management initiative to demonstrate the

efficacy of an integrated approach that can be applied to invaded areas for control of

M~elaleuca. This group has proceeded to implement the control recommendations of the

M~elaleuca Task Force as enumerated in the Florida Exotic Pest Plant Council's

(FLEPPC's) M~elaleuca Management Plan (Pratt and Ferriter 2001). TAME has

subsequently teamed up with the Food and Resource Economics Department (FRED) at

the University of Florida' s Institute of Food and Agricultural Sciences (UF-IFAS) to









conduct this research into the socio-economic impacts of2~elaleuca in South Florida.

Estimates place the coverage of~elaleuca at anywhere from 200,000 to 500,000 acres of

land in South Florida. From 1989-1999 Florida agencies have spent about $25 million on

its control and have succeeded in reducing the area it covers on public land by about

100,000 acres (Pratt and Ferriter 2001).

Problem Statement

A maj or problem with the spread of2~elaleuca is that it causes a reduction of

economically viable uplands and ecologically sensitive wetland areas. A general estimate

of the value of environmental and economic services provided by wetlands is $14,785 per

hectare per year (Costanza et al. 1997). Assuming minimal losses of one percent, and a

current infestation of 200,000 hectares, the diminished value would be almost $30 million

per year. Farmers and ranchers are losing valuable grazing and crop land while natural

areas such as parks/preserves are losing natural habitats, which in turn affect plant and

animal diversity. M~elaleuca invades utility easements such as power lines, canals, and

other waterways, thus impairing their use, and often makes costly tree removal necessary

to maintain the use of these service areas. It has been proj ected that the unfettered spread

of this plant would severely limit the use of parks and recreational areas by tourists and

residents causing a negative impact to the Florida economy at $160 million annually

(Diamond et al. 1991). Additional reports show that by the year 2010 an estimated $1.76

billion in damages would be caused due to the various negative impacts it has on

recreation, ecotourism, fires, and loss of endangered species (Balciunas and Center

1991).

The maj ority of the information gathered through mail surveys focus on elements

traditionally used in determining the extent to which M~elaleuca covered land, how much










was being treated, what methods were being used to treat it, and the costs incurred for

those treatments. However, at the time this research was being carried out it was not

readily apparent that much was known about the negative effects caused by M~elaleuca

infestation. To help bridge the apparent information gap, additional data need to be

collected to determine how individuals perceived the effects that M~elaleuca infestations

have on ecological function, agricultural productivity, land market values, the use of land

for recreation and enj oyment of the outdoors.

Public Lands vs. Private Lands

For many years, the slogan of "Florida State Parks: The Real Florida" was used to

help promote tourism within the State' s park system. The general goal of having these

parks is to allow visitors to see Florida's natural state where it has been left relatively

untouched by human hands. However, invasive species, which often completely

dominate native flora and fauna, thwart the goal of preserving the "real Florida." In order

to meet this goal, non-native species must be removed. This need has been realized by

managers of the public lands and therefore control has been concentrated on these lands.

However, while its removal is a mandate for public agencies, one of the maj or

obstacles facing the success of2~elaleuca control is the fact that private individuals often

implement few or no controls. While it is technically illegal for private individuals to

possess M~elaleuca, very little is actually being done to force them to remove it from their

private property (with the exception of a few pro-active municipalities). This presents the

conundrum of falling infestation rates on public lands, while infestations flourish on

private lands and often cause cross-contamination in areas that have been treated (such as

public lands) or areas that have not yet been infested. The efficiency of treatment is

greatly reduced if public land managers continue to treat and kill M~elaleuca, while










private individuals allow for outlying infestations to spread. A comprehensive strategy

for inducing private citizens to control M~elaleuca is necessary if there is to be any chance

of gaining the upper hand in the war against its spread.

Hypotheses & Parameters Estimated

The issues surrounding the impacts that invasive species have on society are very

broad and far reaching. Previous research on invasive species has mainly focused on the

biological characteristics of the plants. Current research has started to focus on what

kinds of monetary and non-monetary impacts these invaders are having on the economy

and society as a whole. This research seeks to focus more on the socio-economic impact

that M~elaleuca has had on Florida in the region south of Lake Okeechobee. The

hypothesis that will be tested is that this analysis will yield a Benefit Cost Ratio (BCR)

for treating M~elaleuca that is greater than unity (1).

Parameters that will be estimated by this research are:

* What are the impacts/costs of reducing Melaleuca infestations in South Florida?

* What factors influence the choice of control method (or lack thereof)?

* How much money is currently spent on M~elaleuca controls?

* How much money would homeowners be willing to spend to remove Melaleuca
from their property?

* How much money would residents be willing to spend to reduce M~elaleuca in the
places where they engage in outdoor recreational activities?

* What is the BCR for controlling M~elaleuca?

Research Objectives

The general obj ective of this research is to determine the economic impact that

M~elaleuca has had on professional land managers and residents in South Florida, along

with evaluating the socio-economic impact of its control. This will require gathering









information including (but not limited to) which control strategies are currently being

used, how much they cost, and what area is currently being treated. It is hoped that this

research will shed some new light on why individuals are more or less likely to

implement control measures. Then policy makers and implementers can custom tailor

outreach and education programs to increase the area of Melaleuca being treated.

A specific obj ective of this research is to measure the benefits and costs associated

with the treatment of2~elaleuca infestations for the year 2003. Trying to eradicate a

species that has such a stronghold on a large area of ecologically sensitive and

economically valuable land is not cheap. A large amount of money has been and will

continue to be spent if this program is to be considered successful. It is imperative to

determine whether the benefits of controlling this invasive species outweigh the costs.

As a matter of public policy, the resources being allocated to this program should provide

a net benefit to society. A benefit-cost analysis will provide information to determine if

the resources being allocated to this fight are economically justified.















CHAPTER 2
LITERATURE REVIEW

The legislative aim of controlling M~elaleuca has many far reaching implications for

society. Current research is beginning to focus more on the socio-economic impact of

invasive plants. A combination of tools is necessary to fully evaluate the socio-economic

affects of controlling M~elaleuca. Among the tools available, this study employs the use

ofBenefit-Cost Analysis (BCA) and Contingent Valuation (CV) through mail survey

admini strati on.

Introduction to Benefit-Cost Analysis

Every day new proj ects and policies are proposed in both the public and private

sectors. Decision makers are then faced with the daunting task of deciding which of the

myriad proj ects or policies will help to achieve their desired goal or end result. Over

time, BCA has been used extensively to help determine the economic viability of

legislation and investment projects. Since the 1930s BCA has been used by many U.S.

agencies to determine if the benefits of their policies outweigh the costs to society (Prest

and Turvey 1965). Many past U.S. Presidential administrations have recognized the

value that this type of analysis can provide by attempting to clearly delineate the costs

and benefits of a proposed policy/course of action (Whittington and Grubb 1984).

Through Executive Order 12291 signed on February 17, 1981, President Ronald Reagan

sought to standardize and make permanent the requirement for federal agencies to

conduct BCA on all "major" regulations.









Due to the fact that some policies and regulations can result in "win-lose"

situations, analysis needs to identify the winners and the losers and exactly how those

groups will be affected. Sassone and Schaffer (1978) point out that the need for careful

analysis is especially important in large scale public proj ects with irreversible

consequences. A thorough analysis can help to identify normally "unforeseen" costs that

tend to creep up during the life of a proj ect. Policy makers or proj ect managers can then

develop strategies and contingency plans that will help to mitigate these circumstances.

There are many definitions on what constitutes a BCA. However, there are

generally some key similarities between the definitions of the process. One description

suggests that BCA is a "generic term embracing a wide range of evaluative procedures

which lead to a statement assessing costs and benefits relative to proj ect alternatives"

(Sassone and Schaffer 1978, p.3). Another more specific definition states that it is "a

process of identifying, measuring, and comparing the social benefits and costs of an

investment project or program" (Campbell and Brown 2003, p. 1). BCA has been

described as a procedure for "measuring the gains and losses to individuals, using money

as the measuring rod of those gains and losses and aggregating the money valuations of

the gains and losses of the individuals and expressing them as net social gains or losses"

(Pearce 1983, p. 3).

An integral part of a BCA is the identification of all relevant costs and benefits.

Another important step is the quantification of those costs and benefits (Sassone and

Schaffer 1978). It is important to note that these costs and benefits are analyzed by a

"with" and "without" comparison. Specifically, the analysis of the project seeks to assign

a value to the costs and benefits that occur "with" the proj ect and compare them to the









state of the world as it would exist "without" the project (Gittinger 1982). This is

different from considering the state of the world "before" the proj ect and "after" its

implementation. If a "before/after" comparison is used it neglects the change that would

take place without the proj ect and allows for an erred account of the benefits that can be

ascribed to the proj ect/policy. Campbell and Brown (2003) also point out that the

important concept of opportunity cost becomes a factor in the "with and without"

comparison. Without the project, scarce resources such as land, labor, and capital could

be designated to other uses. With the project, the opportunities. to use those same scarce

resources for some other beneficial purpose are foregone. Each possible outcome offers a

particular value to society. After completing a thorough analysis of the two possible

outcomes (with or without the proj ect) and determining the costs and benefits of the

proj ects the analyst can determine if the benefits exceed the costs. If this is the case, then

the proj ect would be recommended to the policy maker.

Formal Theoretical Framework Behind BCA

Using BCA to assign a monetary value to the effects a proj ect will have relies upon

two key assumptions. The first is that the social value of a proj ect is a summation of the

values of the proj ect to individual members of society. The second is that the value of a

proj ect to an individual is equal to their (fully informed) willingness-to-pay (WTP) for

the project (Sassone and Schaffer 1978). Willingness-to-pay is the specific expression of

the value an individual assigns to a commodity or service. This leads to an essential

conclusion in microeconomics that for any given price of a good, rational individuals

aiming to increase their state of well-being as much as possible, will purchase a number

of units of that good so that at the margin, their willingness to pay for that good just

equals its price. Therefore, if an effect of a proj ect were a small increase or decrease in









the number of units of a good accessible to an individual for consumption, that increase

or decrease has a social value equal to the number of units concerned multiplied by the

market price (Sassone and Schaffer 1978).

The formal BCA theoretical framework, reliant upon welfare economics, set forth

by Sassone and Schaffer (1978) indicates that a state (of the world) S is a particular

distribution of utility among the individual members of society; specifically demonstrated

by:

(2-1) S =(U U2, ..., Uj,..., UN),

for a society made up of N members.

A well defined project, through intentional actions, will advance society from the current

state of status quo, So to an alternative state of S'. Vj is the value of a proj ect to an

individual j, and is their maximum WTP amount to have the proj ect implemented (when

they are in favor of the proj ect), and when they do not favor the proj ect, it is the negative

of the minimum amount of their willingness-to-accept as payment in order to remain just

as well off in S' as in So. If the proj ect does not alter individual j's utility then their

compensating variation, Vj = 0. Therefore, the social value of a project is the summation

of the individuals' willingness to pay, identified by C Vj.

Actually acquiring each individual's willingness to pay can be problematic in two

ways (Sassone and Schaffer 1978). First, each individual would have to have perfect

knowledge of every aspect of the project. The impracticality of this is readily apparent

due to the fact that many of the people actually involved with the proj ect are often not

fully aware of every detail. The second difficulty lies within the fact that individuals are

often unable or have difficulty in defining their own compensating variation by stating an









arbitrary number. The aforementioned reasons lead to the suggestion that some other

form of acquiring the individuals compensating variations is necessary. Sassone and

Schaffer (1978) suggest that this information is best gleaned by using interviews or

questionnaires.

Benefit Cost Analysis and Social Welfare Theory

As suggested in the previous section, welfare economics provides a theoretical

basis for BCA. Although BCA did not originally evolve from welfare economics it has

come to rely upon the foundation that welfare economics creates (Cohn 2003). It has

been suggested that BCA is an application of welfare economics (Sassone and Schaffer

1978). While Sassone and Schaffer (1978) provide a very general introductory

framework for BCA (as shown in the previous section), Cohn (2003) provides a more in-

depth analysis into its theoretical basis.

Individual Welfare Changes

Following the assumption that each individual xl, x2, ..., Xn has n goods and

services (including savings) available to him or her, a utility function of Ui for the ith

individual is expressed as:

(2-2) Ui = U(xil, xi2, ..., Xin).

If a new government policy is introduced that has an impact on some of the quantities of

goods and services that individual i consumes, the change in utility ensuing from a

change in the quantity of the jh gOOd or service is defined as:

(2-3) AUi = E(MUij)Axij.

M~Uij describes individual i's marginal utility for an added unit of j, and Axig is the change

in the quantity of good or service j that the individual receives. From the microeconomic










principle stated earlier, it is known that an individual will select goods and services so

that the marginal utility for any good, j, would be equal to the price of the good, pj,

multiplied by the individual's marginal utility of income (M~UYi), given as the following:

(2-4) M~Uij = (M~UYi)pj.

By substituting equation (2-4) into equation (2-3), the following results:

(2-5) AUi = C(M~UYi)pj~xij.

The change in the income of individual i due to the change in the quantities of goods and

services brought about by the new government policy is found in the term pjxij. Finally,

the change in individual i's utility is equal to the change in income weighted by the value

of the individual's marginal utility of income.

Due to the fact that a new government policy will affect many people it is

important to know what change in social welfare is due to the new policy. This can be

found by determining the changes in the individual utilities of m persons affected by the

policy using the social welfare function:

(2-6) W= W(U1, U2, U3, ..., Um),

where Wrepresents social welfare. Taking equation (2-6) into consideration, a change in

social welfare is noted as:

(2-7) AW= M'= (AU1, AU2, AU3, ..., AUm),

where AW represents the change in social welfare.

Keeping in mind that Arrow's Theorem questions the possibility of deriving a

social welfare function at all, Cohn (2003) suggests that the real issue is whether an

"acceptable" function can be developed. One maj or stumbling block for this is the

interpersonal comparison of utility, which some economists argue condemn BCA. While









there are cases when various forms of social welfare functions do not provide an

acceptable social choice, the argument can be made that a flawed social welfare function

is better than none at all. Therefore, equation (2-7) can be differentiated to the form of:

(2-8) dW= C(8W/8Ui)dUi,

to obtain:

(2-9) W = C(M~S~i) Ui,

where M~SUi demonstrates the change in social welfare arising out of the change in the

utility of the ith individual. M~SUi is also known as the distributionall weight" given to

individual i' s utility. In other words, it reflects the societal value of the changes in the

individual' s level of utility.

Substituting equation (2-3) into equation (2-9), the following is obtained:

(2-10) A W= CE(M~UYi,) (M~SUi)pyAxij.

This equation illustrates the changes that occur in social welfare due to a new public

policy that influences the quantities of goods and services available to individuals in

society. It is the sum of the fluctuations in effective income for every individual

weighted by the product of the marginal utility of income of the individual i, (M~UYi,), and

the changes in the quantities of goods and services as a result of the new policy, pj~xij.

Assuming that all individuals have identical marginal utilities of income and changes in

utility associated with the new policy, then the marginal utility of income (M~UYi) and

marginal social utility (M~SUi) will each equal one and the change in social welfare (due

to the new policy) is equivalent to the change in national income due to the policy.

According to Cohn (2003) and Zerbe and Dively (1994), the marginal social

utility and marginal utility of income are difficult to estimate which causes many analysts









to restrict their analyses to the efficiency aspect of the equation. This causes the equation

that reflects the change in welfare to be reduced to:

(2-11) AW= CE pjAxij.

However, it must be kept in mind that if the marginal utilities of income and marginal

social utilities vary significantly among those influenced by the policy, and the end goal

is to maximize social welfare; the BCA could result in erred decisions. If the analyst

feels that ignoring the marginal utilities of income and marginal social utilities is

detrimental then he/she should avoid BCA that does so.

Social Welfare Changes

It should be noted that Arrow' s Impossibility Theorem (originally developed from

research on election procedures) casts some doubt as to whether a social welfare (choice)

function can be derived from an aggregation of individual preferences to allow for the

optimal allocation of resources (Arrow 1963). This is due to the fact that the following

conditions must be met before a "fair" social welfare function can be derived:

* Unrestricted domain or universality. The social welfare function must include each
individual's preferences.

* Non-imposition or citizen sovereignty. All societal preferences should be
achievable through some set of individual preferences.

* There must be at least as many individuals as there are options being debated.

* Non-dictatorship. The social welfare function should not be sensitive to only one
individual. The function is responsive to more than one individual's requirements.

* Monotonicity or positive association of social and individual values. The social
welfare function should promote the change or not change at all if an individual
modifies their preference order. An individual should never be penalized for
modifying their preference.

* Independence of irrelevant alternatives. If the social choice function focuses on a
specific subset of alternatives, then the resulting outcome will be compatible with
those specific alternatives. If individuals change their ranking of "irrelevant"









alternatives it will have no impact on the social ranking of the "relevant"
alternatives. This implies a limitation on the sensitivity of the social function.

Benefit-Cost Analysis in Practice

Benefit Cost Analysis has been used for analyzing a broad spectrum of proj ects.

Stober and Falk (1967) offer a discussion on using BCA for proposed local water

allocation programs to help determine how a community should allot water among the

various needs within a community. Faced with two alternative scenarios, the authors

offer analysis on a reimbursable community proj ect that can supply water at a lower cost

than that at which industrial and municipal users can meet their own needs. By

formulating a benefit-cost ratio (BCR), they can determine if the community project is

justified. They finally determine that the structure of corporate income taxes and the

community's lower costs of capital provide a large bias in favor of the community

supplied water proj ect.

Benefit Cost Analysis has been used to evaluate the economic feasibility of

treatment/eradication programs for other invasive species in Florida. In 2004, Zansler

conducted a BCA of the Citrus Canker Eradication Program (CCEP). This study

investigated the effects that citrus canker would have on the citrus industry if it were

allowed to become endemic, to demonstrate the benefits of the CCEP. Estimates of the

costs were determined by the change in the cost of production and government

expenditures on eradication of citrus groves in Florida.

This form of analysis has been used to estimate the gains and losses from policies

aimed at providing increased product safety for consumers. Dardis, Aaronson, and Lin

(1978) used BCA to evaluate flammability standards of children' s sleepwear as well as

investigating the role BCA plays in determining whether product safety regulations are in










the public interest. The research first delineated the general costs and benefits associated

with implementing this safety regulation. Then, actual monetary values were assigned to

the related benefits and costs of the safety regulation. Upon completing their BCA, the

researchers determined that the new safety standard was cost effective in spite of a

decrease in consumer choice.

Haveman (1976) provides a summary of two cases using benefit cost analysis on

human resource programs. The first case looked at the benefits and costs associated with

the Upward Bound program. This government program was designed to recognize "high

potential, disadvantaged youths" at the high school level, who would probably not be

attending college, and provide them with specialized college preparatory education to

help lessen the education gap for less privileged students. The research evaluated the

benefits and costs of the program from the perspective of the pupils enrolled in it, as well

as the benefits and costs of the program as viewed from the rest of society. The study

determined that the students viewed this program as a worthwhile activity; therefore, they

believed the benefits outweighed the costs (using five and 10 percent discount rates).

The additional analysis indicated that the program's benefits outweighed its costs for the

society at large, as long as the discount rate used is below seven percent.

The second case study addresses the benefits and costs associated with a federal

government program "designed to provide institutional training in occupational skills to

adult workers." The cost-benefit analysis sought to determine if the program was a

valuable social investment. The study showed that increases in the participant' s income

could be attributed to the program. Additionally, social benefits and costs of the

programs were compared to reveal that the length of the program affected the ratio of









benefits to costs. The shorter courses had higher benefit-cost ratios than the longer

courses, where the present value of the costs exceeded the present value of the benefits.

Gittinger (1982) offered analysis on various agricultural proj ects, and specifically

carried out a BCA on the Philippine Ilocos Irrigation Systems Improvement Project by

formulating a BCR for the proj ect.

Blum, Damsgaard, and Sullivan (1980) provided a general discussion of the use of

BCA in health care as it relates to three following areas:

* The use of BCA for analysis of disease-specific programs of intervention from a
prospective point of view (for illnesses such as polio, syphilis, and renal disease).
This has historically concentrated on the economic impact of such diseases
measured by the untimely loss of life or capacity to function due to the illnesses.

* BCA has been used as a technique for the evaluation of alternative means of
delivering medical services. Hospitals have used BCA to assist in determining if it
would be cost effective to construct new ambulatory care centers or if the funds
should be used for improving existing emergent care facilities.

* BCA has been implemented to estimate the return on public investments in areas
such as medical research and health manpower development.

Use of Mail Surveys

Surveys have proven to be a useful tool in many areas of study for gaining insight

into people's opinions and beliefs, or obtaining general quantitative information. More

surveys are conducted by mail than through any other means (Dillman 1991). The U.S.

Office of Management and Budget' s 1984 research reported that 90 percent of the

government' s surveys categorized as "self-administered"' were conducted through mail

procedures. The use of mail administered surveys has distinct advantages and

disadvantages (Dillman 1991, Benson 1946, and Kramer and Schaffer 1954).

One of the greatest advantages that has helped mail surveys gain popularity is the

relatively low cost of implementing mail surveys when compared with interviews









conducted in person or by telephone. The relative simplicity of administering mail

surveys allows organizations and individuals to conduct the surveys themselves as

opposed to hiring outside agencies. Mail surveys also make it possible to contact

individuals when they are scattered across a broad geographic region. Additionally, by

accessing the necessary lists of potential respondents, mail surveys can be efficient at

reaching specific subsets of the population such as college graduates, homeowners, or

agricultural land owners. When mail surveys are used, the interviewer bias observed in

phone surveys or personal interviews is eliminated. When anonymity is assured by the

entity conducting the survey, the respondent is likely to be more forthcoming in mail

questionnaires as opposed to personal interviews. Finally, when the necessity arises to

gather responses from all household members, mail surveys allow those members to be

reached relatively easily as opposed to scheduling additional interviews if all the

necessary members are not available at one particular time.

One of the disadvantages of using mail surveys is that it is impossible to tell

whether the respondent answered on their own or solicited answers from outside sources.

If it is imperative that the respondent give only their personal opinion or answer questions

based on their current level of knowledge, then mail surveys cannot assure this. The goal

of gaining a representative sample of the population can be problematic, because those of

higher education and/or income levels may be more likely to reply than those of a lower

socio-economic class. Another difficulty is that the responses gathered by mail surveys

can be biased towards those who are inclined to one or extreme or the other. In other

words those with more polarized biases are more likely to respond than those who are

uninformed or have more moderate positions on the subj ect.









Due to the threat of respondent fatigue, mail surveys must be kept relatively brief

to avoid non-responses attributed to a lengthy questionnaire document. Furthermore, the

importance of question sequence is lost on mail surveys due to the fact that nothing really

prevents the respondent from perusing the whole questionnaire before actually answering

the questions. Finally, only a limited amount of demographic information can be gleaned

from mail surveys. Respondents often feel that this line of questioning is too invasive,

especially when copious amounts of personal information are requested.

It is imperative for a researcher to consider the pros and cons of the various

methods used to gather survey information. No one survey method can be endorsed as

better than another; the decision must be made on a case by case basis. According to

Kramer and Schaffer (1954) when considering the disadvantages of a technique the

researcher must ask if:

* They are factors that would significantly influence the results of the survey?

* Does the disadvantage limit the scope of the technique or does it eliminate the
technique for their particular area of inquiry?

* Does the disadvantage apply to all survey techniques or just the particular one
being considered?

* Are there any techniques to mitigate the disadvantageous effects?

The Contingent Valuation Method (CVM)

It is especially difficult to measure or put a monetary value on irreplaceable goods

like health or the environment. Often the market fails to establish prices for public goods

because they are nonexclusive. This is why there is the need to find out what values

people place on these public goods. Hanemann (1994) points out that a survey or

questionnaire offers a way to demonstrate public demand for a good, especially when

indirect methods fail to offer a complete measure of a person's value for a particular









good. While price systems are one way to determine how people establish what

something is worth; another way is to simply ask them through surveys or votes

(Schelling 1968).

Mitchell and Carson (1989) submit that in general, the Contingent Valuation

Method (CVM) appears as accurate as other methods, and is capable of measuring types

of benefits that other methods can measure only with difficulty, if at all. The fact that

economists now have a tool to value goods, previously thought almost impossible to

value, has helped this valuation method gain worldwide popularity (Navrud 1992). The

CVM uses survey questions to determine an individual's preferences for public goods by

establishing what they would be willing to pay for specific improvements in them; thus

eliciting their willingness-to-pay (WTP) or willingness-to-accept (WTA) some loss in

dollar amounts (Mitchell and Carson 1989). If the study has been carefully designed and

pre-tested, the responses gathered should symbolize valid WTP responses (Mitchell and

Carson 1989). If the random sample gathered has a sufficiently high response rate and

appropriate measures are taken to adjust for non-respondents and poor quality responses,

the results can be generalized (with a known margin of error) to represent the population

from which the sample was taken (Mitchell and Carson 1989). The Carson et al. (1994)

bibliography lists more than 1600 studies and papers from more than 40 countries that

used CV on varied topics such as transportation, sanitation, health, the arts and education,

and the environment.

While there is no one standard for the design of contingent valuation surveys, it is

important for them to include several key elements, because the quality of responses is

directly related to the quality of the design of the survey. To begin, the survey must









contain a clear description of the policy/program that the respondent is valuing (Portney

1994). If a clear description is lacking, the respondent will likely be less able to

accurately value the situation in question. The survey must include a means for eliciting

a value or a choice from the respondent, through the use of tools such as referendum

formats, open-ended questions, or bidding games (Portney 1994). Finally, CV surveys

usually seek to gather the demographic information of the respondents along with their

attitudes toward the environment or a description of their recreational behavior for

environmental and/or natural resource studies (Portney 1994).

While the CVM is widely used around the world, the subj ect is not without debate

or its detractors. In 1992 a panel of experts, including Nobel laureates, was convened to

advise the National Oceanic and Atmospheric Agency (NOAA) if the "CVM was capable

of providing estimates of lost nonuse or existence values that were reliable enough to be

used in natural resource damage assessment" (Portney 1994, p.8). While the "bottom

line" of the panel report found that "CV studies can produce estimates reliable enough to

be the starting point of a judicial process of damage assessment, including lost existence

values," they also developed a strict and lengthy framework under which CV studies

should be conducted if they were to produce reliable estimates (Portney 1994, p. 8).

Among those guidelines, the panel stated that face-to-face interviews are preferred to

telephone surveys and telephone surveys are preferred to mail questionnaires, and that

studies should gather information on willingness to pay to prevent future incidents

instead of determining minimum compensation required for an event that has already

occurred. Additionally, studies using CV should implement the referendum format,

where respondents are asked how they would vote for a particular program that would









achieve some level of environmental benefit in exchange for higher taxes or commodity

prices. The panel offered that the reasoning behind this guideline is that these types of

decisions more accurately reflect the reality of real world decisions and would provide a

more accurate valuation than the typical open-ended question that seeks a maximum

willingness-to-pay value. The panel also stated that analyses using the CVM should open

with a scenario to accurately illustrate the anticipated effect of the program being

considered as well as a reminder that a willingness-to-pay amount for the proposed

policy/program would reduce their disposable income. Finally, follow-up questions

should be provided to ensure that the individual could comprehend the choice they were

being asked to make and to discover the reasoning behind their response.

Some economists critical of the CVM have charged that it is not useful because, in

their view, the resulting information is contrary to economic theory (Hanemann 1994).

To that end, critics have suggested that the CVM is insensitive to scope, thereby making

it an unreliable method for obtaining useful information regarding natural resource

damage estimates. Kahneman and Knetsch (1992) put forth that their study of WTP for

the clean-up of lakes in Ontario, Canada shows that respondents' WTP to clean up all of

the lakes in Ontario is less than the WTP for the clean up of lakes in a specific region.

Logic would suggest that an individual's WTP for cleaning up a larger number of lakes

would be higher than their WTP for cleaning up a smaller area of lakes. It has been

argued that this insensitivity to scope is unavoidable because "respondents are expressing

ideological values, receiving a warm glow, or purchasing moral satisfaction"

(Kahnemann and Knetsch 1992, p. 64). The NOAA panel also included a requirement

that studies using the CVM should test for the sensitivity of responses to the scope of the










damage described in the scenario. To address this issue the panel suggested that the

questionnaires should seek to determine whether or not the respondents were willing to

pay more to prevent more serious ecological accidents.

Previous Research on the Economic Impacts of Melaleuca

While the biological research on M~elaleuca is now quite extensive, there is a

noticeable paucity in the amount of economic research that has been conducted on this

invasive species. However, there are a few researchers who sought to analyze the

economic impacts that M~elaleuca has had in Florida relatively early in the eradication

program's life. Balciunas and Center (1991) discussed the prospects and dilemmas that

could arise if biological control is used in the fight against Melaleuca. Additionally, they

conducted a Benefit Cost Analysis under the assumption that M~elaleuca is allowed to

spread unchecked. Their research helped to provide a good starting point for the benefits

and costs to be enumerated. For the purpose of this research, however, the Balciunas and

Center research is used as a guide to show the worst case scenario for the negative

impacts of2~elaleuca.

Diamond, Davis, and Schmitz (1991) also provided additional research on the

economics of the M~elaleuca invasion. They specifically considered the economic impact

associated with the addition of2~elaleuca to the Florida Prohibited Aquatic Plant List and

provided a more extensive Benefit Cost Analysis of the spread of2~elaleuca. The

authors went into great detail considering possible effects of~elaleuca on Florida' s eco-

tourism, sport fishing and game hunting, as well as its effects on Florida agriculture and

the ecosystem in general. They also specifically provided useful cost figures for the

economic damages caused by wildfires fueled with M~elaleuca. Their research helps to

provide a checklist of sorts to ensure a thorough analysis. However, due to the fact that









both of the previously mentioned articles were written during the early stages of the

M~elaleuca eradication/treatment initiative, and the changes that have taken place since

then, they will have a rather limited application in this research.















CHAPTER 3
SURVEY DESIGN, CONTENT, AND ADMINISTRATION

Survey Methods

As discussed in the previous chapter, this research used mail surveys to gather part

of the information necessary to this proj ect. The quality of a survey's design is arguably

the deciding factor as to whether it will yield useful and reliable data. Over time,

research has been undertaken to try to devise a recipe, of sorts, that survey designers can

follow to help increase the likelihood that their surveys will yield their greatest potential.

This research uses Dillman's (1978) Total Design Method (TDM) as a guide for survey

design.

Survey Study Area, Target Populations, and Sampling

The study area for these surveys included the 10 southernmost counties in Florida:

Broward, Charlotte, Collier, Glades, Hendry, Lee, Martin, Miami-Dade, Monroe, and

Palm Beach. Just over 2.5 million households are located in these counties (BEBR,

2004).

For the residential survey, a randomly selected sample of 5,001 households, which

represented 0.2 percent of the population, was purchased from a market research firm

(MSG, Inc.). Due to the fact that many Hispanic non-English speaking individuals reside

in South Florida, a Spanish language version of the survey mirrored each page of the

English version.

Both agricultural owners/operators and managers of public parks/preserves were

targeted for the survey of professional land managers. Agricultural land owners were









selected from a list compiled from county property appraisers by the Florida Department

of Revenue in Tallahassee. A random sample of 2,000 landowners with property

classified for agricultural use was selected for the survey. This sample represented 17

percent of the population of about 1 1,500 landowners.

For public lands, a list of 285 names was obtained from the United States

Department of Agriculture-Agricultural Research Service (USDA-ARS) representing

managers of parks and preserves for local, state, and federal government agencies, and

managers of rights-of-ways for public utilities. Surveys were mailed to all managers on

this list.

Survey Content

Beginning in fall 2003, two separate questionnaires were developed for the

respective survey groups of residents and professional land managers. The content of

these questionnaires was developed in consultation with The Areawide Management

Evaluation of Melaleuca (TAME M~elaleuca) proj ect collaborators at the University of

Florida Institute of Food and Agricultural Sciences (UF-IFAS), USDA-ARS, and the

South Florida Water Management District (SFWMD). The questionnaires and informed

consent protocol for the survey were reviewed and approved by the University of Florida

Institutional Review Board (UF-IRB) for compliance with ethical standards for human

subject research. Following the suggestions in Dillman's (1978) TDM, each survey had

an arrangement of various colored photographs on the front cover. Inside the front cover

included an introductory statement explaining who was conducting the study, the purpose

of the questionnaire, the importance of providing a response, general instructions for

completing and returning the questionnaire, the anticipated length of time for completion

of the survey, a guarantee of confidentiality, contact information should the participant









have any questions, and a statement of gratitude for participating in the study. The

residential survey was seven pages in length for each language, yielding 14 total pages,

inclusive of the opening instructions and areas provided for comments. The professional

land manager survey was a total of nine pages. Each survey concluded by thanking the

respondents for their participation and asking that they return the questionnaire in the

postage-paid envelope provided. Copies of the survey materials are provided in the

Appendix.

Residential Survey

The residential survey was designed to help provide some insight into attitudes,

opinions, and experiences with M~elaleuca by the general public. The survey

questionnaire focused on determining the extent of residents' knowledge and experience

with both invasive plants and M~elaleuca specifically. The content of the survey can be

broken down into three categories: (1) an introductory assessment of experience with

and knowledge of2~elaleuca, (2) an assessment of opinions and willingness-to-pay

information, and (3) demographic information. An introductory line of questions were

posed to determine the respondent' s level of awareness of invasive plants in the state.

Residents were asked to indicate if they could recognize M~elaleuca and if they were

aware of its non-native status. Then, respondents were asked to indicate how much, if

any, M~elaleuca was located on their property. The next questions in the survey sought to

determine what control methods residents were currently using or interested in learning

more about, along with any factors that limited their ability to control the plant.

Residents were also asked to indicate from which sources they received information

about Melaleuca. The first section ends by asking the respondent to estimate what range

of money they had spent (since 1990 or owning their property) specifically for the control









of Melaleuca on their property. If the amount was over $500 the respondents were asked

to write in the estimate.

The second section began by asking respondents to indicate whether they felt that

M~elaleuca had negatively affected their property value. If the respondent answered

"yes", they were asked to then indicate by what percentage it had negatively affected the

value. Residents were also asked to indicate how much they would be willing to pay to

remove/eradicate M~elaleuca on their property. If they were willing to pay more than

$500 they were asked to write in a specific amount. Respondents were then given a list

of outdoor activities and asked to indicate how many days they engage in those activities

on an annual basis. The respondent was provided with space to write-in an activity that

was not listed. Residents were asked if Melaleuca had in any way affected their

enj oyment of the outdoors. If the respondent answered yes, they were then asked to

specify if they had been negatively or positively affected. The second section concluded

by asking respondents to indicate how much they would be willing to pay, per visit, to

reduce M~elaleuca in the areas where they engage in outdoor recreational activities. If the

amount was more than $25 per visit, they were asked to write-in a specific amount.

The third and final section of the residential survey sought to gather demographic

information about the respondent. Information was gathered on the zip code in which

they resided, the duration of residence at their current location, and the ownership status

of their residence. Questions such as gender, year of birth, educational achievement,

ownership of 25 or more acres of land in Florida, participation in state/local elections,

household size, and pre-tax income (for 2003) were also asked. Space was also provided









for the respondents to add any comments they had as well as to indicate their name and

address if they wished to receive a summary of the survey results.

Professional Land Manager Survey

While there are some similar questions in the two surveys, the survey administered

to the professional land managers was intended to gather more technical information on

the level of infestation and practices used for the control of~elaleuca. Both professional

agricultural land managers and park/preserve managers received the same survey

questionnaire. The content of the manager' s surveys can be broken down into two

categories: (1) general descriptive information reflecting the management unit, and (2)

specific information on M~elaleuca control. In the first segment, managers were asked to

indicate their name followed by their organization's name, address, and telephone

number. They were then asked to specify in which counties their land holdings or

management units were located. In order to determine the ownership classification of

their land, managers were asked to indicate how much of their land was privately owned,

publicly owned, or privately leased. To gather more specific information on the land's

use, managers were asked to indicate how many acres of their land fell within certain

categories, such as cropland, commercial timberland, park/preserve, etc. In the hopes of

gaining some insight into the factors affecting land management decisions, respondents

were asked to indicate whether various factors exerted significant, moderate, or no

influence over their management choices. The managers were then asked to report how

many acres of exotic plants currently occupied their management area as well as indicate

how many acres of each plant had been treated from 1990-2003.

The section of the survey specifically designated to acquire information on

M~elaleuca began by asking managers to indicate what control methods they had used on









M~elaleuca. They were then asked to specify the area treated for each control used during

2003 and from 1990-2003. Managers were also asked to indicate if they had not used

any control measures for Melaleuca. Respondents were asked to indicate whether they

planned to continue using or to adopt specific control measures for M~elaleuca, and

indicate if they would like to receive more information on any of the control types listed,

as well as indicate the types of sources that provided M~elaleuca control information to

them. Managers were asked to indicate any reasons that limited their ability to control

M~elaleuca on their property. Additionally, the managers were asked to rate the

usefulness of the information in terms of "useful", "somewhat useful", or "not useful".

Respondents were asked to indicate the costs for control of2~elaleuca on their

management unit during 2003 as well as indicate the total expenses for any special

equipment or heavy machinery purchased specifically for the control of~elaleuca since

1990. The survey went on to ask respondents to indicate if the total costs of Melaleuca

control on their land had increased, decreased, or stayed about the same over the past five

years. Managers were also allowed to indicate that they "didn't know" the trend. If the

respondent indicated that the costs had increased or decreased they were asked to indicate

by what percentage. Respondents were also asked to indicate if they felt that M~elaleuca

had reduced their land's agricultural productivity, lowered its market value, impaired its

ecological function, or diminished its recreational use. If the respondent indicated that it

had negatively affected one of these aspects they were asked to provide the percentage

loss that Melaleuca had caused. Professional managers were also asked to indicate their

organization' s gross income or annual budget for land management from 2003.

Participants were given the option of writing in a specific amount, indicating a range, or









indicating that they did not know the amount. Finally, managers were given the option of

adding additional comments as well as indicating whether they would like a copy of the

results through the mail or e-mail.

Survey Administration

Survey administration was begun in June 2004 following the protocol of the TDM

(Dillman). An introductory letter was first mailed to all targeted respondents to notify

them that they had been selected for the survey, explaining the purpose of the survey, and

requesting their cooperation. Approximately one week later, questionnaires were mailed

along with a postage-paid return envelope and a cover letter restating the purpose of the

study. Reminder postcards were mailed one week later. A second complete mailing of

the survey and reminder postcard was repeated six weeks later.

After the completed surveys were received from respondents and categorized into

the appropriate group (i.e.-park/preserve managers, agricultural managers, and

homeowners) a code number was assigned to each completed questionnaire. The survey

responses were entered into an Excel worksheet and then verified for accuracy. If contact

information was provided in the response, follow up phone calls or emails were used for

verification or clarification as necessary.















CHAPTER 4
SURVEY RESULTS

Results for Professional Managers

Land Ownership Status

Land area owned and leased by professional managers responding to the survey is

summarized in Table 4-1. A total of 5.4 million acres were reported, which consisted of

about 5.1 million acres controlled by park managers and 317,000 acres controlled by

agricultural mangers. The vast maj ority of land managed by park/preserve managers was

publicly owned, although 86,372 acres were privately owned.

In contrast, most of the land managed by agricultural managers was privately

owned. Publicly owned landholdings managed as parks/preserves averaged 74,488 acres

per manager, and ranged in size from four acres to 1,400,000 acres. Privately owned

agricultural landholding averaged 775 acres per manager and ranged from less than 1

acre to 140,000 acres. A relatively small amount of land was being privately leased by

both park and agricultural managers. When these numbers are expanded to represent the

full population of agricultural managers in the 10 county study area of South Florida, an

estimated 1.74 million acres would fall under private ownership, 73,893 acres would be

privately leased, and 8,884 acres would be classified publicly owned.

Land Use

In terms of land use, some 6.94 million acres were reported managed by

park/preserve managers, and 319,771 acres were reported managed by agricultural

managers, giving a total of 7.26 million acres (Table 4-2).










Table 4-1. Land area managed by surveyed professional land managers in
Florida.
Sum Mean Minimum Maximum
Classification INumber
(Acres) (Acres) (Acres) (Acres)
Park/Preserve
80 5,084,967
Managers
Privately Owned 10 86,372 8,637 7 70,000
Publicly Owned 67 4,990,670 74,488 4 1,400,000
Privately Leased 3 7,925 2642 105 7,500
Agricultural
Managers 431 316,528
Privately Owned 390 302, 132 775 0.3 140,000
Publicly Owned 3 1,545 515 5 1,380
Privately Leased 38 12,851 338 1 2,700
Overall Total 511 5,401,495 10,570 1 1,400,000

The largest type of land-use by area as reported by survey respondents was for

parks/preserves, comprising a total of 4.80 million acres, or 73,883 acres per manager.

The next largest land uses reported by park managers were right-of-ways totaling

871,483 acres, followed by lakeshore (508,272 acres), mitigation areas or constructed

wetlands (373,017 acres). Miscellaneous other uses totaling 356,262 acres included target

ranges, recreational areas, and office buildings. Some park/preserve managers indicated

that some of their land was used for pasture/range land, crop production, fruit/citrus

groves, and nurseries, but none indicated that their land was being used as forest for

commercial timber production.

The most commonly reported land use by agricultural land managers was

pasture/rangeland, with 38 percent of respondents reporting a total of 143,243 acres,

averaging 853 acres per respondent. Crop land was the next largest land use reported

totaling 116,388 acres, followed by fruit/citrus groves (34,275 acres), and right-of-ways

(4,547 acres). Miscellaneous other uses totaling 18,272 acres reported by agricultural

managers included residences, ponds, horse farms, and barns. When these numbers are









expanded to represent the population of agricultural managers in South Florida, it is

estimated that a total of 1.83 million acres were being managed, including 823,647 acres

for pasture/rangeland, 669,231 acres for crop land, 197,081 acres for fruit/citrus groves,

and 26,145 acres for right-of-ways, and 105,064 acres for miscellaneous other uses.


Table 4-2. Land use types and areas managed by p -ofessional land managers ir Florida.
All
Park Managers Agricultural Managers Managers
Land Use Type
Mean Sum Mean
# Sum (Ac) # Sum (Ac)
(Ac) (Ac) (Ac)
Park/Preserve 65 4,802,389 73,883 8 30 4 4,802,419
Right of Way 16 871,483 54,468 36 4,547 126 876,030
Lakeshore 6 508,272 84,712 7 19 3 508,291
Miti gati on/W etl and 14 373,017 26,644 9 25 1 28 373,268
Pasture/Range 4 25,210 6,303 168 143,243 853 168,453
Crop 2 900 450 50 116,388 2,328 117,288
Fruit/Citrus 3 1,908 636 98 34,275 350 36,183
Nursery 5 19 4 103 1,395 14 1,414
Forest 0 10 1,351 135 1,351
Other Use(s) 16 356,262 22,266 83 18,272 220 374,534
Total of all uses 6,939,460 319,771 7,259,231

Factors Affecting Land Management

Survey respondents were asked to rate various factors that influenced their land

management decisions as either "significant", "moderate", or "none" (Table 4-3). These

factors included agency funding, adverse weather conditions, availability of agricultural

land, encroachment of urban land uses, foreign or other state competition, cost of inputs

or supplies, prices for crops, fruit, or livestock, invasive plants, predators, insect pests,

and the ability to conduct prescribed burns. The average ratings for each of these factors

are summarized in Figure 4-1, where each respondent's rating was assigned a number

value: 0 for "none", 1 for "moderate", and 2 for "significant".










For park/preserve managers, agency funding was the most influential factor in land

management decisions; being rated as significant by 77% and moderate by 19%. Perhaps

this is not surprising since many of these respondents work for local, state, or federal

agencies. Invasive plants were rated as a significant factor by 73% of park managers,

while 25% rated them as a moderate influence. The ability to conduct prescribed burns

was rated as significant by 39% of park/preserve managers, and as moderate by 23%.

Input costs were considered significant by 36% and moderate by 53% of park/preserve

mangers. Urban encroachment was rated as a significant or moderate influence by 28%

and 40% of these respondents, respectively. Adverse weather was viewed as a moderate

influence (71%), although this may be considered more important after the 2004

hurricane season. Only 8% indicated that predators or insect pests were a significant

factor in their management, while 42% rated these pests as moderate, and 50% gave

considered it of no significance. Factors other than those listed in the survey (such as the

general public, staffing, and wildfires) were rated as significant by 38% of park/preserve

managers. Factors that were considered to have little or no affect on the park/preserve

management decisions were prices (99%), availability of agricultural land (93%), and

competition (86%).

For agricultural managers, factors influencing land management were rated lower

overall. Prices for crops, fruit and livestock was the most important factor, with 29%

indicating it was significant and 33% as moderate. The costs for inputs or supplies were

rated as a significant factor by 24% of agricultural managers and as moderate by 41%.

Adverse weather conditions were a significant factor for 23%, urban encroachment was

rated as significant by 23%, and availability of agricultural land was significant for 20%.









The latter finding may be due to the fact that most agricultural managers already

own/lease their land, so they aren't worried about acquiring any additional land, or it may

indicate that agricultural managers generally do not intend to expand their operations.

Some 19% of agricultural managers rated predators and insect pests as a significant

factor, with 46% rating them as moderate. Invasive plants were rated as significant by

16% and as a moderate influence by 43%. Foreign or other state competition was

generally not viewed as important, which is somewhat surprising given the significance

of commodity prices.

Table 4-3. Factors influencing management decisions by professional land managers in
Florida.
Park Managers Agricultural Managers
Factor None Moderate Significant None Moderate Significant
% % % % % %
Agency funding 4 19 77 91 7 2
Adverse weather 15 71 15 40 37 23
Availability of ag. land 93 7 0 51 30 20
Urban encroachment 33 40 27 50 27 23
Competition 86 13 1 73 15 12
Costs 12 53 36 35 41 24
Prices 99 1 0 39 33 29
Invasive plants 3 25 73 41 43 16
Predators/ Pests 50 42 8 36 46 19
Prescribed burns 38 23 39 66 26 8
Other factors 44 19 38 89 3 8






























0.7

0.7


M 0.2

0. 1.0

0.8


0.7 1 7

0.9


0.91
0.42


Other Factors affecting mgmt.

Ability to conduct prescribed burns

Predators/ Pests

Invasive Plants

Prices

Costs


Competition

Urban Encroachment


Availability of Ag. Land

Adverse Weather


MAgricultural Managers
0.9 H Park Managers




1.0


Agency Funding .

0 0.5 1 1.5 2
Average Significance


Figure 4-1. Average weighting of factors influencing management by professional land
managers .

Area Occupied By Invasive Plants and Area Treated

The importance of2~elaleuca as an invasive plant was assessed in relation to other


invasive plants, based on the area currently occupied in 2003, and the area treated during


the period 1990 to 2003. The area occupied was intended to represent the areas of

contiguous stands, not very small isolated patches and individual outlying trees. The ratio


of area treated since 1990 to the area occupied currently was also taken as a gauge of the


intensity of treatment by land managers.


For park/preserve managers, M~elaleuca was the invasive plant reported to occupy

the largest area (619,317 acres) in 2003. M~elaleuca also had the largest area treated


during 1990-2003 (402,088 acres), which represents 65% of the area currently occupied.









Brazilian Pepper was the second most common invasive plant, occupying 425,805 acres

in 2003, with 75,215 acres treated between 1990 and 2003. This represented 18% of the

area occupied in 2003. Among other species, Old World Climbing fern (Lygodium)

occupied 1 13,884 acres, and 49,213 acres were treated (43% of area occupied).

Australian Pine (Casuarina) occupied 111,782 acres, with 16,598 acres treated (15%),

Cogon grass (Imperata) occupied 20, 147 acres, with 6,527 acres treated (32%), Tropical

Soda Apple (Solan2um) occupied 15,418 acres, with 3,475 acres treated (23%), and

miscellaneous other plants occupied 11,433 acres, with 7,094 acres treated (62%). Some

of the other plants frequently listed were air potato (Dioscorea bulbifera), downy rose

myrtle (Rhodomytrus tomentosa), latherleaf (Colubrina a~siatica), carrot wood

(Cupaniopsis anacardioicles), and cattail (Typha).

For agricultural managers, 94 managers reported a total area of 2,134 acres

occupied by Melaleuca in 2003, and 57 managers reported treating a total of 1,460 acres

during 1990-2003. This represented 68 percent of area occupied. This suggests that

agricultural managers have treated M~elaleuca at similar rates as park managers have,

however other indicators in this survey and other research imply that park managers have

acted much more aggressively. Tropical Soda Apple (Solan2um) was reported by

agricultural managers to occur on 10,393 acres in 2003, and 7,855 acres (or 76% of this

area) were treated. Brazilian Pepper (Schinus) occupied 7,096 acres and 2,768 acres

(39%) were treated. Miscellaneous other invasive plants, including air potato, dog fennel,

and smut grass, occupied 2,561 acres, and 2,094 acres (82%) of those plants were treated.

When these numbers are expanded to represent the total population of agricultural

managers, Melaleuca is estimated to cover 12,271 acres in South Florida during 2003,









and 8,395 acres were treated between 1990 and 2003. The area infested by other invasive

plants on agricultural lands is estimated at 139,058 acres, including 59,760 acres for

Tropical Soda Apple, and 40,802 acres for Brazilian Pepper (Schinus).

Table 4-4. Land area infested with and treated for invasive species by professional managers
in Florida
Park/Preserve Managers Agricultural Managers
Area
Area Currently Area Treated Area Treated
SpeiesOccupied Since 1990 Crety Since 1990
Occupied
# Acres # Acres # Acres # Acres
Paper bark or Punk
tree (M~elaleuca) 59 619,317 54 402,088 94 2,134 57 1,460
Australian Pine
(Ca~suarina) 55 111,782 50 16,598 29 34 15 5
Brazilian Pepper
(Schinus) 68 425,805 65 75,215 146 7,096 104 2,768
Cogon grass
(Insperata) 33 20, 147 31 6,527 14 320 9 73
Old World Climbing
fern (Lygodium) 45 113,884 40 49,213 23 178 16 24
Torpedo grass
(Panicunt) 33 25,060 31 11,008 40 1,468 31 888
Tropical Soda Apple
(Solanunt) 32 15,418 25 3,475 37 10,393 32 7,855
Other plants 37 11,433 36 7,094 33 2,561 18 2,094
Total 362 1,342,846 332 571,218 416 24,184 282 15,167

Methods Used for Treating Melaleuca

Managers were asked indicate if they had used a specific method for controlling

M~elaleuca and then to indicate the area they treated with that method in 2003 and also

cumulatively from 1990 to 2003. Respondents were given a choice of several options:

Mechanical removal (felling, mowing, tilling, grubbing, disking, etc.)

Foliar or soil applied herbicides

Basal frill followed by herbicide treatment (also known as "hack and squirt")

Girdling followed by herbicide treatment (a ring of bark is removed from the base
of the tree and then treated with an herbicide)










* Felling followed by herbicide treatment on the cut stump ("stump treatment")

* Biological control with beneficial insects (natural enemies of the tree are released
which may cause stress in established trees and death of younger saplings)

* Biological controls combined with one or more other methods.


Since respondents were given the opportunity of indicating more than one control

method, a count was taken to see how many managers chose at least one control choice,

and this number was used to compute the percentage of managers responding in the

affirmative for using a particular control method.

Among park/preserve managers, 82% indicated they had employed the stump

treatment, 59% used hack and squirt, 51% used mechanical control methods, 28%

employed biological control, 21% used biological control combined with one or more

other form(s) of control, and 7% reported using some other method of control such as

fire.

Many agricultural managers did not have M~elaleuca on their property, and if they

did, many chose not treat it. So, it was not surprising that 71% of agricultural managers

had not used any particular control measures for Melaleuca. Among agricultural

managers who did use controls, 33% indicated they had employed mechanical methods

for control, 10% used foliar or soil applied herbicides, 8% reported using stump

treatment, and 4% used hack and squirt (Table 4-5).










Table 4-5. Methods used for treatment of2~elaleuca by professional land managers in
Florida.

Metho UsedPark Managers Agricultural Managers
Number Percent Number Percent
Mechanical 31 51 70 33
Foliar/Soil herbicides 22 36 20 10
Hack and Squirt 36 59 8 4
Felling and herbicide (stump treatment) 50 82 16 8
Biological Control 17 28 3 1
Biological control + other method 13 21 0 0
Other methods 3 74 2
No Controls 13 21 149 71

The area of2~elaleuca treated using various control methods in 2003 and

cumulatively during the period 1990-2003 is summarized in Table 4-6. The total area

treated in 2003 was 86,731 acres, and the total area treated since 1990 was 422,449 acres.

For park/preserve managers, the total area treated in 2003 was 84,740 acres, and the area

treated since 1990 was 419,741 acres. The stump treatment (felling + herbicide) was used

over the largest area (303,933 acres) since 1990, followed by hack and squirt (52,476

acres), foliar or soil applied herbicides (36,622 acres), mechanical methods (16,625

acres), and biological control (12,642 acres). Biological controls combined with one or

more other methods) were used on 80,575 acres, and together with the area treated

strictly by biological control represented 93,217 acres. For area treated in 2003, the most

important method used was stump treatment (46,958 acres), followed by foliar/soil

herbicides (15,987 acres), and hack and squirt (11,494 acres). In comparing the area

treated in 2003 with the average annual rates since 1990, it is apparent that the use of all

treatment methods has accelerated in 2003 for parks/preserves.

For agricultural managers, overall area of2~elaleuca treated by any particular

method since 1990 was significantly less than the park/preserve managers, at about 2,707









acres, including mechanical methods (1,957 acres), stump treatment (274 acres), and

foliar/soil-applied herbicides (3 55 acres). The smaller area treated for 1990-2003 than for

2003 in some cases was apparently due to reporting errors.


Table 4-6. Number of professional managers using various control methods and area of
M~elaleuca treated in Florida, 2003 and 1990-2003.
Park Managers Agricultural Managers Total Area
Area Treated Area Treated Area Treated Area Treated Treated
2003 1990-2003 2003 1990-2003 1990-2003
Method Used
# Acres # Acres # Acres # Acres (Acres)
Mechanical 20 4,592 22 14,669 43 1,367 37 1,957 16,625
Foliar/Soil
Herbicides 15 15,802 15 36,267 15 185 8 355 36,622
Hack and Squirt 23 11,454 28 52,437 7 40 5 39 52,476
Felling + Herbicide
(stump) 37 46,562 37 303,659 14 396 10 274 303,933
Biological Control 7 6,310 10 12,600 2 3 2 42 12,642
Biological + Other 4 4,242 6 80,575 0 0 0 0 80,575
Other Control 3 20 3 110 0 0 1 40 150
Total* 109 84,740 121 419,742 81 1,991 63 2,707 422,449
* Total area excludes biological plus other control methods, to avoid double counting.

Managers were also asked to indicate whether they planned to use or continue

using various control methods (Table 4-7). Among park/preserve managers who

answered this question, the largest share intended to use stump treatment (85%), followed

by hack and squirt (72%), mechanical control (50%), and biological control (45%), or

biological control combined with other methods (40%). For agricultural land managers,

the maj ority intended to use mechanical methods (79%), with much fewer intending to

use foliar/soil applied herbicides (29%), stump treatment (27%) or "hack and squirt"

(16%). Very few agricultural managers expressed interest in biological control.









Table 4-7. Intentions for future use of various M~elaleuca control
methods by professional managers in Florida.
MethodPark< Managers Agricultural Managers
Number Percent Number Percent
Mechanical 30 50 58 70
Foliar/Soil herbicides 23 38 24 29
Hack and Squirt 43 72 13 16
Felling + Herbicide 51 85 22 27
Biological Control 27 45 4 5
Biological + Other 24 40 3 4
Other Methods 3 5 6 7

Managers were also asked whether they were interested in receiving additional

information about any of the specific Melaleuca control methods (Table 4-8). Most

park/preserve managers were interested in learning more about biological control (74%),

but a maj ority was also interested in foliar/soil applied herbicides and stump treatment

(65%), hack and squirt (58%), and mechanical methods (52%). Among agricultural

managers who responded to this question, 40% to 50% wished to learn more about

biological control, stump treatment, soil/foliar herbicides and hack and squirt. The low

interest in learning more about mechanical control, at the same time this group expects to

continue using this method extensively, suggests that this method is well understood.

Table 4-8. Requests for more information on Melaleuca control methods by
professional managers in Florida.
Method Park Managers Agricultural Managers
Number Percent Number Percent
Mechanical 16 52 12 25
Foliar/Soil herbicides 20 65 22 45
Hack and Squirt 18 58 22 45
Felling + Herbicide 20 65 24 49
Biological Control 23 74 24 49
Biological + Other 16 52 17 35
Other Methods 5 16 3 6









Barriers to Controlling Melaleuca

Land managers were asked to choose from a list of factors that may have limited

their ability to control M~elaleuca (Table 4-9). Among park/preserve managers, the

biggest barriers identified were inaccessibility to infestations (22%), expense (18%),

excessive size of infestations (15%), lack of cost sharing programs (13%), and lack of

time (12%). However, a significant proportion of these respondents (32%) indicated they

encountered other types of barriers not specifically identified in the question. Some of

these other barriers included: infestations are too small, lack of needed equipment or

knowledge to use controls, fear of harming other beneficial plants, fear of or dislike for

using chemicals, and environmental regulations. Although they were listed in the

question, some respondents wrote-in that lack of money and lack of time were barriers to

implementing controls. Only 13% of park/preserve managers said that M~elaleuca was not

a problem for them.

Agricultural land mangers responded quite differently to the barriers to control

question. Seventy-four percent indicated that they did not have M~elaleuca on their

property and 3 1% reported that M~elaleuca was not a problem for them even it they did

have it. Some 9% of agricultural managers reported that their infestations were too small,

6% indicated that controls were too expensive, 5% indicated they lacked the necessary

equipment to carry out control measures, and 5% indicated a barrier other than those

listed in the survey. No particular barrier was mentioned more than any other; however,

some respondents stated that there were no economic incentives for removing M~elaleuca,

that licenses were needed for purchasing the necessary herbicides, and that some areas

required permits for removing the trees. It is interesting to note that one respondent










stated that Melaleuca trees provide shade in pastures, which suggests that there may be

some benefits of2~elaleuca for agricultural use.

Table 4-9. Barriers to controlling M~elaleuca by professional managers.
BaniersPark Managers Agricultural Managers
Number Percent* Number Percent*
No M~elaleuca on property 17 281 227 74
Not a problem 8 13 96 31
Don't care 0 01 13 4
Infestations too small 5 81 28 9
Infestations too large 9 15 8 3
Controls won't work 0 01 3 1
Don't know how to use controls 3 51 8 3
No time to use controls 7 121 3 1
Afraid of harm 3 51 5 2
Afraid oflDislike 3 5 13 4
Infestation inaccessible 13 221 6 2
Lack equipment 5 81 16 5
Environmental regulations 2 3 4 1
No cost sharing 8 13 12 4
Controls too expensive 11 181 19 6
Other reason 19 321 14 5
* Percent of respondents answering this question.

Sources and Usefulness of Information for Melaleuca Control

Professional land managers were asked if they had received information about

M~elaleuca from one or more of 13 possible sources (Table 4-10). These respondents

were also asked to classify the usefulness of these sources as either "useful", "somewhat

useful", or "not useful" (Table 4-11). These classifications were scored on a scale of 2, 1

or 0 respectively in order to compute a weighted average rating (Figure 4-2).

Park/preserve managers who responded to this question indicated that state and

federal agencies were their main source of information, with 83% indicating that they had

received information from these sources, followed by UF/IFAS extension (72%), land

managers' advice (67%), pamphlets or bulletins (60%), land managers' observations










(58%), and professional organizations (52%). Other information sources or media that

were received by less than 50 percent of respondents were weed professionals, area

demonstration plots, TAME M~elaleuca, video cassettes or CDs, internet websites,

computer software, and email. In terms of the usefulness of information from state and

federal agencies, 88% of park/preserve managers rated it as a useful source, 10% rated it

as somewhat useful, and 2% indicated it was not useful (Table 4-11), representing an

overall average score of 1.9 (Figure 4-2). Other information sources with high usefulness

ratings were UF/IFAS extension (1.9), manager observations (1.8), land manager advice

(1.8), weed professionals (1.8), professional organizations (1.7), internet websites (1.7),

pamphlets/bulletins (1.6), and the TAME proj ect (1.6).

Table 4-10. Information sources and types of media used by professional land
managers in Florida.
Sources Park Managers Agricultural Managers
Number Percent Number Percent
State and federal agencies 50 83 31 44
Professional organizations 31 52 16 23
Land manager observations 35 58 12 17
UJF/IFAS extension 43 72 33 47
Weed professionals 25 42 10 14
TAME M~elaleuca 22 37 5 7
Land manager advice 40 67 13 19
Pamphlets or bulletins 36 60 17 24
Video cassettes or CDs 9 15 4 6
Area demonstration plots 12 20 4 6
Computer software 3 5 4 6
Web site/Internet 21 35 14 20
E-mail/direct notification 15 25 4 6
Other information source 5 8 9 13

Among agricultural managers who responded to this question, 47% indicated they

had received information from UF/IFAS extension, followed by state and federal

agencies (44%), pamphlets/bulletins (24%) and professional organizations (23%) (Table

4-10). In terms of usefulness, the top rated sources were UF/IFAS extension (1.4),



























1.3

0.11.
.0
1.7
0.1
0.7

0.21.


0.4 1.2
09
1.6
1.1
1 R



1 9

11 R
.9 1.7

1.9


49



manager observations (1.1), state/federal agencies (1.1), weed professionals (1.1), land


manager advice (1.1), and internet websites (1.1) (Figure 4-2). None of the agricultural


managers indicated they considered area demonstration plots, computer software/decision


aids, or email/direct notifications as being useful sources.


Other media Specified

E-mail

Website/ Internet

Software Decision aids

Demonstration plots

VideolCD's

Pamphlets/ Bulletins

Land Manager's Advice



Weed Tprofe~ssironlst

UF/lFAS extension

Manager's Observations

Professional Organization

State & Federal Agencies


MAgricultural Managers
HPark Managers


0 0.5 1 1 .5 2 2.5
Average Rating


Figure 4-2. Usefulness rating of information sources and media by professional land
managers in Florida










Table 4-11. Usefulness of information received by professional land managers in South
Florida.
Park Managers Agricultural Managers
Source Somewhat Not Somewhat Not
Useful Useful
Useful Useful Useful Useful
Percent of Respondents
State/federal agencies 88 10 241 26 33
Professional organizations 77 19 5 37 20 43
Land mgr. observations 79 19 247 19 34
UF/IFAS extension 88 10 261 16 23
Weed professionals 79 18 3 52 4 44
TAME Melaleuca 63 30 713 7 80
Land mgr. advice 81 15 447 20 33
Pamphlets or bulletins 62 33 426 41 33
Video cassettes or CDs 43 36 21 14 7 79
Area demonstration plots 53 29 18 0 21 79
Computer software 14 43 43 0 14 86
Web site/Internet 79 15 640 16 44
E-mail/direct notification 47 37 15 0 14 86
Other information source 75 25 021 21 57

Costs for Melaleuca Control

Managers were asked to indicate the costs incurred during 2003 for the control of

M~elaleuca within the categories of contract services, labor (including wages and

benefits), equipment (fuel, maintenance, and rental), herbicides, and indirect costs (such

as administration and overhead). The total annual cost for controlling M~elaleuca for

surveyed park/preserve managers was $10.87 (Mn.). This included $8.07 Mn. for

contract services, $837,000 for labor costs, $796,000 for herbicides, $308,000 for

equipment, $330,000 for indirect costs, and $528,000 for costs miscellaneous other costs

(Table 4-12). Surveyed agricultural managers reported spending $205,000 in 2003 to

control M~elaleuca, with $130,000 for contract services, $29,000 for labor, $22,000 for

herbicides, $18,000 on equipment, and $5950 on indirect costs. If these numbers are









expanded to represent all agricultural managers in South Florida, a total of $1.18 Mn is

estimated to have been spent by these managers on controlling M~elaleuca in 2003.

Table 4-12. Costs for M~elaleuca control reported by professional land managers in
Florida, 2003.
Park Managers Agricultural Managers
Expense
# Sum ($) Mean ($) Max ($) # Sum ($) Mean ($) Max ($)
Contract services 34 8,066,544 237,251 4,060,00 8 129,900 16,238 100,000
Labor 29 837,470 28,878 400,00 17 28,975 1,704 20,000
Equipment 26 308,428 11,863 225,00 18 17,855 992 5,000
Herbicides 33 796,401 24,133 425,00 19 21,610 1,137 15,000
Indirect 19 329,770 17,356 110,00 5 5,950 1,190 5,000
Other 7 527,500 75,357 500,00 1 500 500 500
Total 10,8 66, 113 204,790

Managers were also asked to indicate expenses for any special equipment or heavy

machinery purchased since 1990 specifically to control M~elaleuca. It is important to note

that these expenses may be partly captured in the previous section under annual costs for

equipment expenditures. Among park/preserve managers surveyed, 28% reported

spending a total of $1.44 Mn for special equipment, with a maximum expenditure of

$1.20 Mn, as shown in Table 4-13. Some 7% of agricultural managers reported spending

$244,000 on special equipment, which would represent a total of $1.40 Mn when

expanded to represent the population in the region.

Table 4-13. Expenses for special equipment for Melaleuca control by
professional managers in Florida.
Category Number Mean ($) Sum ($) Maximum ($)
Park Managers 25 57,556 1,438,900 1,200,000
Agricultural Managers 33 7,390 243,879 130,000

Managers were asked about how costs for controlling M~elaleuca on their land had

changed over the past five years; whether they had increased, decreased or remained the

same. If there had been a change, they were asked to indicate the percentage change










(Table 4-14). Among park/preserve managers, 21% indicated that costs had increased,

26% indicated that costs decreased, and 32% indicated no change. Of those who

indicated that costs had increased, the average estimated change was 253 percent, while

for those who said costs had decreased, the estimated average decline was 117 percent.

For agricultural managers, 11% indicated the costs had increased, 9% indicated a

decrease and 41% indicated that costs had stayed about the same. For those indicating a

change in costs, the average increase was 81% and the average decrease was 87%.

These results suggest that costs for M~elaleuca control may be increasing more for

park/preserve managers than for agricultural land managers. A plausible explanation

could be the fact that most park/preserve managers are managing sensitive ecosystems

and are mandated to control invasive plants such as M~elaleuca in order to keep their

management area in a more naturally pristine state. Many agricultural managers do not

seem to think that M~elaleuca is much of a problem so they are probably less interested in

removing it, along with the fact that some mangers find that it sometimes provides

benefits for their operations.

Table 4-14. Melaleuca treatment cost trends reported by professional land
managers in Florida.
Park Managers Agricultural Managers
TrendAverage
TrendAverage
Number Percent Change Number Percent
Change (%)
Increased 13 21 2531 11 11 81
Decreased 16 26 1171 9 9 87
Unchanged 20 32 40 41
Don't know trend 13 21 37 38

Impacts of Melaleuca

Information was sought from managers regarding any negative impacts that

M~elaleuca had on their land and management over the past Hyve years. The first part of










the question provided the respondents with a list of options as well as giving them the

opportunity to specify any other adverse impacts. A second part of the question sought to

quantify the impact in terms of the percentage change in function. Among park/preserve

managers, 88 percent of those who indicated any impact reported that M~elaleuca had

impaired the ecological function of their management area, while 3 5 percent indicated a

reduction in the recreational use or value of their land (Table 4-15). A small number of

park/preserve managers reported other impacts such as increased fire danger, restriction

of necessary clearances, and smoke management issues with prescribed burns. Among

agricultural land managers who answered this question, 59% indicated that M~elaleuca

had reduced their land's agricultural productivity, while 39% said it impaired ecological

function of their land and diminished its recreational use, and 20% said that their land

market values were reduced (Table 4-15). Some of the other negative impacts listed

included allergies caused by pollen and various maintenance problems such as damage by

falling trees to fences.

Table 4-15. Negative impacts of2~elaleuca reported by professional
land managers in Florida.
Agricultural
Park Managers
Impact Managers
Number Percent Number Percent
Reduced Agricultural
Productivity 0 024 59
Lowered Market Value 0 0 8 20
Impaired ecological function 35 88 16 39
Diminished recreational use 14 35 16 39
Other impacts 4 10 8 20

As a follow-up, managers were asked to estimate the percentage change in value

or utility due to M~elaleuca infestation. Park/preserve managers estimated that the loss of

ecological function and recreational use averaged 23 %, while agricultural managers









estimated that M~elaleuca had caused an average loss of 25 % in recreational use and 24%

in agricultural productivity (Table 4-16).

Table 4-16. Reduction in utility due to M~elaleuca infestation reported by professional
land managers.
Park Managers Agricultural Managers
Impact Mean Min Max Mean Min Max
(%) (%) (%) (%) (%) (%)
Reduced Agricultural
Productivity 0 18 24 3 100
Lowered Market Value 0 6 11 5 20
Impaired Ecological Function 24 23 1 10 11 22 1 50
Diminished Recreational Use 8 23 1 10 12 25 5 100
Other Impact 1 30 30 30 3 43 5 100

Annual Income or Budget and Comparison of Reported Melaleuca Control
Expenses

Professional managers were asked to indicate their gross income from agricultural

operations or their agency's budget for land management activities for the year 2003, or

to indicate the appropriate range of values (Table 4-17). A small percentage of

park/preserve managers (16%) reported their actual budgets, which totaled $9. 1 Mn, and

averaged $650,000. Among park preserve managers, 30% indicated their budget was less

than $50,000, 7% said it was within the range of $50,001-$99,999, 11% indicated it was

$100,000 to $249,999, 9% said it was $250,000 to $499,999 range, 5% said it was

$500,000 to $999,999, and 29% indicated their annual income/budget was $1,000,000 or

more. Among agricultural managers, 10% reported actual income totaling $7.83 Mn.

Some 55% indicated their budget was less than $50,000, 6% had $50,001 to $99,999,

12% had $100,000 to $249,999, 2% had $250,000 to $499,999, 3% had $500,000 to

$999,999, and 6% had $1,000,000 or more.

Reported expenses for the control of~elaleuca were compared to reported income

or budget in order to gauge the relative level of effort allocated to this effort. If managers









chose to write in their income, that exact figure was used in the comparison., however, if

their income/budget was reported for a range of values, then the midpoint for that range

was used, and for the highest and lowest ranges (less than $50,000, $1 million or more)

$25,000 and $1.5 million were used, respectively. Only managers who reported both

expenses and budget/income information could be used for this analysis. The analysis

revealed that on average 38 % of park managers' budget was expended on control

measures for Melaleuca, as a weighted average. For some managers, reported expenses

were as much as 3 to 8 times more than their budget. A few of the respondents indicated

that less than 1% of their income/budget was used on controlling M~elaleuca. These

outliers may be due to reporting errors or may simply be due to the fact that some

agencies/operations are involved in deficit spending, i.e. spending more than their budget

provides.

Table 4-17. Annual income or budget for land management by south
Florida professional managers, 2003.
Agricultural
Park Managers
Income/Budget Range Managers
Number Percent Number Percent
Less than $50,000 17 30 105 55
$50,001--$99,999 4 7 12 6
$100,000--$249,999 6 11 22 12
$250,000--$499,999 5 9 3 2
$500,000--$999,999 3 5 5 3
$1,000,000 or more 16 29 12 6
Don't know 5 9 32 17

Appoxmae mont Number Mean Sum Max
Reported
Park Managers 14 650,386 9, 105,400 4,385,000
Agricultural Managers 46 170,213 7,829,795 2,450,000


For agricultural managers, an average of 4% of their income was spent controlling

M~elaleuca. The majority of these managers fell into the 1 to 5% range, and some










reported their control expenses were less than one percent, however, some indicated that

60 to 100% of their income went to controlling M~elaleuca.

Results for Residents

Invasive Plant Awareness

Citizen awareness of non-native flora and in the state of Florida is an important

issue for the management of invasive plants. In the resident survey, a series of questions

were included to gauge the public's level of knowledge about invasive plants generally,

and M~elaleuca in particular. The vast maj ority of the respondents (91%) indicated they

were aware that some plants and trees are not native to the State. Nearly as many (89%)

indicated they were aware that non-native plants could harm local indigenous plants. A

strong maj ority (71%) responded that they could recognize M~elaleuca, and an equal

percentage indicated that they were aware it was not native to Florida (Table 4-18).

Table 4-18. Awareness of2~elaleuca and invasive plants by Florida residents.
Number Percent
Awareness Issue
No Yes No Yes
Aware some plants are not native to Florida 85 898 9 91
Aware non-natives can cause harm 109 875 11 89
Can recognize M~elaleuca 288 689 30 71
Aware M~elaleuca isn't native to Florida 280 700 29 72
Currently have M~elaleuca on property 921 37 96 4

Amount of Melaleuca on Property

When residents were asked if they had any M~elaleuca on their property, only 4%

indicated in the affirmative. Of those who had M~elaleuca, 3 1% indicated they had only

one tree, 16% had two to five trees, and 31% had six to 20 trees. Three percent of

residents with Melaleuca had one-quarter to one-half of an acre of land infested, 9% had

one to four acres, and 6% indicated they had five or more acres of2~elaleuca on their

property (Table 4-19).










Table 4-19. Amount of2~elaleuca on
property of Florida residents.
Trees or acres Number Percent
One tree 10 31
Two-five trees 5 16
Six-20 trees 10 31
0.25 acre 1 3
0.5 acre 1 3
1-4 acres 3 9
5 + acres 2 6

Use of Control Methods for Melaleuca

The respondents who stated that they had M~elaleuca on their property were asked

to indicate which, if any, of the listed control methods they were currently using. Some

84% of residents indicated they had not used any control measures (Table 4-20).

Mechanical controls were used by 12 percent, foliar/soil-applied herbicides or stump

treatment were used by 3% each, while 1% indicated they had used hack and squirt,

biological control, or biological combined with some other control.

Table 4-20. Methods used for Melaleuca control by Florida residents,
and interest in more information about control methods.
Interested in Learning
Methods Used
Method About
Number Percent Number Percent
Mechanical 23 12 13 50
Foliar/Soil herbicides 5 3 18 69
Hack and Squirt 1 1 16 62
Felling + Herbicide 5 3 18 69
Biological Control 2 1 21 81
Biological + Other 2 1 16 62
Other Methods 0 08 31
No controls used 157 8


The respondents who had M~elaleuca were also questioned regarding control

methods they would be interested to learn more about. There was a very high level of

interest in learning more about biological controls, with 81% of respondents expressing










such an interest (Table 4-20). A maj ority of respondents were also interested in learning

more about foliar/soil-applied herbicides (69%), stump treatment (69%), hack and squirt

(62%), and biological control combined with other methods (62%). Interest was lower for

mechanical controls (50%). Some 31% indicated they were interested in some other

method of control, however, none specified what the other methods might be.

Barriers to Controlling Melaleuca

Residents were given a list of factors that potentially limit their ability to control

M~elaleuca and asked to indicate which of those factors applied in their case. Of those

respondents who indicated any barrier, 56% said that M~elaleuca was not a problem, 20%

did not care, 19% were afraid of or disliked using chemicals, 15% did not know how to

use controls, 13% lacked the necessary equipment, and 10 percent gave other reasons

(Table 4-21, Figure 4-3).

Table 4-21. Barriers to controlling M~elaleuca by Florida residents.
Barrier Number Percent
Not a problem 80 56
Don't care 29 20
Infestations too small 9 6
Infestations too large 12 8
Controls won't work 5 3
Don't know how to use controls 21 15
No time to use controls 9 6
Afraid of harm to other plants 6 4
Afraid of or dislike using chemicals 28 19
Infestation inaccessible 9 6
Lack equipment 18 13
Environmental regulations 3 2
No cost sharing 3 2
Controls too expensive 5 3
Other reason 15 10












Information Sources for Melaleuca Control

Residents were given a list and asked to indicate which sources and types of media

they had received information from or on the control of2~elaleuca (Table 4-22). The

most common source of information was newspaper, reported by 59% of those

responding to this question, followed by local/national news (47%), and state and federal

agencies (42%). Other sources were public television (29%), pamphlets/bulletins (28%),

UJF/IFAS extension (27%), weed professionals (17%), and professional organizations

(12%). Some miscellaneous other sources mentioned by 17% of respondents included

word of mouth, park or garden club tours, public speakers, personal research, or

educational classes. Finally, only 1% of respondents indicated that they had received

information from the TA1VE 2elaleuca proj ect.

Table 4-22. Sources of information on M~elaleuca received by Florida
residents .
Source Number Percent
State and federal agencies 152 42
Professional organizations 44 12
Land manger observations 20 6
UF/IFAS extension 96 27
Weed professionals 61 17
T AVE M~elaleuca 4 1
Land manager advice 23 6
Pamphlets or bulletins 166 28
Video cassettes or CDs 0 0
Area demonstration plots 20 3
Computer software 1 0
Web site/Internet 27 5
E-mail/direct notification 20 3
Local/national news 283 47
Newspapers 353 59
Public television 176 29
Other sources) 103 17










Expenses for Melaleuca Control

Residents were asked to indicate how much they had spent on controlling

M~elaleuca since owning their present property, or during the period 1990-2003, by

choosing the appropriate range of values or by estimating the amount if their

expenditures exceeded $500. As shown in Table 4-23, 93% of residents indicated they

had spent $0-$49, and it is most likely, given previous data, that the maj ority of

respondents in this category probably paid zero. One percent of respondents indicated

that they had spent $50 to $99. Nearly 2% spent $100 to $249 and the same number

spent between $250 and $500. Slightly over 2% of respondents spent more than $500 on

Melaleuca control. For those reporting expenses over $500, the average amount was

$1,992, representing a total of $1 1,950. If these numbers are expanded to represent the

entire population of households in South Florida, an estimated $15.3 million was spent on

M~elaleuca control.

Table 4-23. Expenses for M~elaleuca control
by Florida residents, 2003.
Expense Range Number Percent
$0-$49 380 93
$50-$99 4 1
$100-$249 7 2
$250-$500 7 2
$500+ 9 2

Impacts on Property Values

Residents were asked to indicate whether and by how much M~elaleuca had

negatively affected their property value. As shown in Table 4-24, 5% reported that

M~elaleuca had negatively affected their property value, and that values were reduced by

an average of 18 percent. However, the maj ority (95%) said it had not affected their

property value.










Table 4-24. Negative effect of2~elaleuca on property
value of Florida residents.
Effect Number Percent
140 440 95
Yes 24 5
Number 11
If Yes, amount
Mean (%) 18
specified (%)
Max (%) 50

Willingness to Pay for Melaleuca Removal/Eradication

Residents were also asked to indicate the dollar amount they would be willing to

pay to have M~elaleuca removed or eradicated from their property. If respondents

indicated they were willing to pay more than $500, then they were asked to estimate the

amount. As shown in Table 4-25, 74% of residents indicated they would be willing to

spend $0 to $49, however, since many residents previously indicated M~elaleuca was not

a problem for them, the maj ority of respondents for this category likely would choose $0.

Only 11% indicated they were willing to spend $50 to $99, 6% would pay $100 to $249,

7% would pay $250 to $500, and 2% would pay more than $500. Of those respondents in

the last category, the amount they would be willing to pay averaged $1,500. When these

numbers are expanded to represent the population of households in South Florida it is

estimated that residents would be willing to spend a total of $13.7 Mn to have M~elaleuca

removed from their property, which is similar to the estimated amount actually spent (see

above).










Table 4-25. Willingness to pay for removal of2~elaleuca
from property by Florida residents.
Expense Range Number Percent
$0-$49 224 74
$50-$99 34 11
$100-$249 19 6
$250-$500 20 7
$500+ 5 2
Number 3
If more than
Sum 4,500
$500, amount
Mean 1,500
specified
Max 2,500

Impacts of Melaleuca on Outdoor Enjoyment

Residents were asked about the number of days per year they spent in various

outdoor recreational activities, and how 2elaleuca has affected their enj oyment of the

outdoors. Residents reported a total of 8,790 days per year observing/photographing

wildlife, 8,132 days for boating or ATV activities, 6,263 days for freshwater fishing,

3,434 days for camping/hiking, 601 days for hunting, and 22,475 days for other activities

such as golf, jogging, cycling, walking, gardening, tennis, swimming, and saltwater

fishing (Table 4-26). When asked about how M~elaleuca had affected their enj oyment of

the outdoors, 77% indicated that it had not affected them and 23% said it had (Table 4-

27). Furthermore, 95% of those affected said it had negatively affected their enj oyment of

the outdoors, while only 5% indicated it had positively affected them.









Table 4-26. Days of annual outdoor recreation activity reported by
south Florida residents, 2003.
Activity Number Sum Mean Max
Wildlife observation/
photography 261 8,790 34 365
Boating/ ATV 304 8,132 27 200
Camping/ Hiking 242 3,434 14 150
Freshwater fishing 6,263
Hunting 49 601 12 75
Other Activity 207 22,874 111 1,000


Table 4-27. Effect of2~elaleuca on outdoor
enj oyment by Florida residents.
Response Number Percent
No 598 77
Yes 179 23
If Yes--Negative Effect 179 95
If Yes--Positive Effect 9 5


Willingness to Pay to Reduce Melaleuca in Outdoor Activity Areas

Residents were asked how much they would be willing to pay (per visit) to reduce

M~elaleuca in areas where they engaged in outdoor activities. They were given several

ranges of amounts, and if they were willing to pay more than $25 per visit were asked to

estimate the amount. Some 44% of respondents indicated they were willing to pay

nothing, 8% would pay something less than $1 per visit, 27% would pay $1 to $4, 9%

would pay $5 to $9, 7% would pay $10 to $15, 4% would pay $16 to $25, and 1% would

be willing to pay more than $25 (Table 4-28). When these numbers are expanded to

represent the population of households in South Florida, these residents would be willing

to pay an estimated total of $1.35 million to reduce Melaleuca in the areas where they

engage in outdoor activities.










Table 4-28. Willingness to pay per visit to reduce M~elaleuca
in recreational areas by Florida residents.
Expense Range Number Percent
$0 275 44
$0-$1 48 8
$1-$4 171 27
$5-$9 58 9
$10-$15 42 7
$16-$25 23 4
$25 + 9 1
Count 5
If more than $25 Sum $500
estimated amount Mean $100
Max $200

Respondent Demographics

Demographic information such as age, gender, property ownership, household size,

and income were collected as part of this survey, to help understand factors influencing

attitudes and behavior toward M~elaleuca and other invasive plants. This information is

summarized in Table 4-29. In regard to length of residency, 63% had lived in their

current location for more than five years, 33% had lived there for one to five years, and

4% had lived there less than one year. Regarding property ownership, 89% of

respondents indicated they owned their home, and 2% owned agricultural, forestry or

other natural land in Florida. Some 57% of residents were male and 43% were female.

The average year of birth was 1947, the oldest respondent' s year of birth was 1911 and

the youngest was 1985. Regarding education level, 14% had a high school diploma or its

equivalent, 11% had completed a technical/trade school, 26% had some college education

or an AA degree, 23% had a bachelor' s degree, and 23% had a graduate or professional

degree. Some 80% of respondents indicated they had voted in a state or local election in

the last three years. A household size of 2 people was reported by 91% of respondents.









Regarding household income before taxes, 5% made less than $10,000, 7% received

$10,000 to $19,999, 12% received $20,000 to $29,999, 8% received $30,000-$39,999,

16% received $40,000 to $49,999, 6% received $50,000 to $59,999, 15% received

$60,000 to $79,999, 12% received $80,000 to $99,999 range, and 20% indicated they

made $100,000 or more.











Table 4-29. Demographics characteristics of surveyed south Florida residents,
2003.


Variable
Residency duration


Residence ownership

Gender

Year of birth


Education level







Ownership of 25 or
more acres in Florida
Voted in state or local
Election in Past 2
Years
Number of people per
household
Household income
before Taxes


Level
Less than 1 year
1-5 years
5+ years
Lease
Own
Female
Male


Number
33
309
584
104
827
399
524
892
1947
1911/1985
26
132


Percent
4
33
63
11
89
43
57



3
14


Mean
Min/Max
Less than high school diploma
High school diploma or
equivalent
Some college or AA degree
Technical/Trade School
Bachelor' sDegree
Graduate/Professional Degree
No
Yes
No
Yes


Mean
Less than $10,000
$10,000-$19,999
$20,000-$29,999
$30,000-$39,999
$40,000-$49,999
$50,000-$59,999
$60,000-$79,999
$80,000-$99,999
$100,000+


241
102
214
210
926
19
183
757

921
2.4
37
52
89
60
121
47
116
89
149















CHAPTER 5
BENEFIT COST ANALYSIS

The primary data used for this analysis were gathered by the previously discussed

mail questionnaires; however, some additional data were gathered from other sources.

After the survey data and the additional data gathered were verified, analysis was

conducted to ascertain the benefits and costs of treating M~elaleuca in South Florida

during the year 2003.

This task included delineating the monetary values associated with a loss in

ecological function due to M~elaleuca infestation. Due to time constraints, monetary

values specific to South Florida ecosystems could not be generated by this research.

However, Constanza et al. (1997) provides the average global values of ecosystem

services based upon a synthesis of previous work. The analysis provides estimated

annual values for ecosystem services per unit area by ecosystem type. This research will

utilize these values assess a monetary value to ecosystem function gains from the

treatment of Melaleuca.

Due to the fact that park/preserve managers indicated that M~elaleuca diminished

the recreational use of the land they managed, a monetary value was assessed to the

losses in recreational value that were avoided by the treatment of the infested areas. The

Florida Department of Environmental Protection (FDEP) Division of Recreation and

Parks provided an estimate of the direct economic impact of the state park system

(Baxley, pers. comm.). The National Park Service and Florida State park's economic

impact of visitor spending at parks are based on the Money Generation Model 2 (MGM2)










developed at Michigan State University (MGM2 2003). The analysis provides

information as to the number of days visited by both local and non-local visitors, the

amount of money spent per day, the j obs created, tax revenue generated, the output

(revenue) generated by the parks, and other economic impacts generated by visitor

spending.

Calculation of Benefits

This analysis focuses on valuing benefits to ecological function, agricultural

productivity, agricultural land market value, and recreational benefits from M~elaletca

treatments on public and privately held lands. It is assumed that benefits can only accrue

in areas where M~elaletica has actually been killed and accrue immediately after treatment

and that a year of benefits accrues regardless of what time of the timing of treatment. In

addition it is important to note that just because an infestation of 2elaletica is treated

once does not mean that the j ob is done. Due to the tenacity of the species, multiple

follow up treatments are usually necessary for permanent control to be achieved. Annual

benefits may be diminished if sufficient follow up treatments are not implemented. A

model was developed that relates the areas of2~elaletica treated on specific categories of

land to a specific ecosystem value to calculate the benefits accruing to that land. The

equations used to determine the benefits of2~elaletica control are as follows:

90 10 445 10
(5-1) EB = RI le ((Aj/Mj)E(CjDx)) + R ItF C((Ak Mk) (xkDx))
j= 1 x= 1 k= 1 x= 1

445 6
(5-2) APB = RP Ib F C((Ak/Mk) C(xk)),
k= 1 x= 3

445 6
(5-3) MVB = RV Im F C((Ak/Mk) C(xk)),
k= 1 x= 3











(5-4) RB = R Y Ir C((Aj/Mj) (Cxij))/L,
j=1


where the dependent variable EB represents the ecosystem benefits, the dependent

variable APB represents the agricultural productivity benefits, the dependent variable

MVB represents the agricultural land market value benefits, and RB represents the

recreational benefits. Cx is the acreage of land classified for a specific use (xl...xio), as

reported by each individual park/preserve manager (j) or agricultural manager (k). Each

x value corresponds directly to the land use classification listing from the survey, where

xl represents land used as park/preserve, x2 TepreSents right of way, x3 TepreSents

pasture/rangeland, x4 is crop land, x5 is fruit/citrus grove, x6 is nursery, x7 is forest, xs is

wetlands, x9 is lakeshore, and xlo is other uses. The variable M represents the total

management acreage reported by each park/preserve manager (j) or agricultural manager

(k), A is the acreage of Melaleuca treated as reported by each park manager (j) or

agricultural manager (k), and R is the effective rate of treatment. The variable I,

represents the percentage reduction in value reported averaged across responding park

and agricultural managers to ecosystem services, agricultural productivity, land market

value or recreational use of land reported by park managers (noted by the subscripts e and

r) and agricultural managers (noted by subscripts t, b, and m) as matched to the

corresponding equation. The variable F is the expansion factor used to expand the

sample results of agricultural managers to represent the entire population, Dx is the

ecosystem value adjusted for inflation from Costanza et al. (1997), P represents the

average market value (cash receipts per acre of land in agricultural production) of

agricultural products produced in the 10 county survey region, V represents the average









market value of land and buildings per acre in agricultural production in the 10 county

survey region, Y represents the total economic output of all of the state parks, and two of

the maj or national parks in the survey area, and L represents the total area of

park/conservation land in the 10 county survey region as reported by the Florida Natural

Areas Inventory (FNAI 2005).

Ecosystem Benefits

In equation 5-1, the division of the Cx term by the M term yields the proportion

that indicates how much of the manager' s land area is devoted to particular uses. The

percentage this calculation yields is then multiplied by the acreage of2~elaletica treated,

represented by A, as reported by the park manager (j) and the agricultural manager (k).

This part of the equation is made necessary due to the fact that the professional managers

separately reported their land areas managed and the areas of2~elaletica that were

treated. That is to say, based upon the information gathered in the survey, there was no

delineation as to the land use classification of the infested area treated. Therefore, it

became necessary to make the assumption that the reported area of2~elaletica treated was

proportionally distributed among the nine possible land use designations reported by the

individual managers. For example, if a manager reported that they managed 120 acres of

pasture or rangeland and 30 acres of cropland, and that they treated 60 acres of2~elaletca

on their management site, then 48 acres of the M~elaletica was assumed to be treated on

rangeland while 12 acres was treated on cropland. This assumption allows for the areas

of~elaletica treated to be broken down by land use classification into the nine possible

classifications, which in turn, allows for an ecosystem function value to be properly

assigned to each land use classification. In equation 5-1 all land use classifications are

considered, due to the fact that most terrestrial areas provide some sort of ecological









function, even if it is somewhat diminished. The Costanza et al. value assigned to the

proper land use classification builds in an allowance for any diminished value in

ecological function. For example, the ecological function of cropland is only valued at

$108/hectare/year, while the function of wetlands is valued at $17,393/hectare/year.

As mentioned earlier, the tenacity of2~elaletica makes it difficult to kill. After

speaking with vegetation management experts from the South Florida Water

Management District and Everglades National Park, it was determined that the minimum

rate of kill to be reasonably expected after properly treating M~elaletica was

approximately 90 percent (Laroche and Taylor, pers. comm.). When contractors are

hired to go into an area and treat a Melaletica infestation, they are contractually obligated

to guarantee that the existing infestation will be reduced by at least 90 percent. Therefore

the R variable represents the effective rate of treatment and is a constant .90. This

adjustment is made to the area of2~elaletica treated, reported by managers, to allow for

the most realistic outcome of treatment to be represented within this benefit equation.

The variable Dx represents the ecosystem value described by Costanza et al.

(1997) that is assigned to the corresponding land use classification from the survey.

Costanza et al. report their values in 1994 U. S. dollars per hectare which were adjusted

for inflation to reflect current 2003 dollars using the GDP implicit price deflator 1.176 as

provided by the United State Department of Commerce (USDOC 2006). Additionally,

the treatment area figures reported by the managers in acres were converted to hectares.

Costanza et al. provides a value for land generally classified as terrestrial, but also

provides values for specific subcategories of land such as, forest, grass/rangelands,

wetlands, lakes/rivers, and cropland. The land use categories from the survey were









matched up with a terrestrial biome value so as to provide a dollar value per hectare for

the function of that ecosystem. Table 5-1 shows the Costanza et al. values adjusted for

inflation and assigns those values with the corresponding land use classifications from the

survey. As shown below, there are six possible amounts and they are applied to the 10

particular land use classifications reported by managers.

Table 5-1. Ecosystem Values for Surveyed Land Use Classifications.
Ecosystem Value adjusted Corresponding Land Use from
Classification for Inflation using Survey
GDP Implicit
Price Deflator
($/ha/year)
Terrestrial 946 Right of way, Other
Forest 1,140 Park/preserve, Forest
Grass/rangelands 273 Pasture/rangeland
Wetlands 17,393 Mitigation area/constructed wetland
Lakes/rivers 9,997 Lakefront
Cropland 108 Crop, Fruit/citrus grove, Nursery

The next term, I (with the sub script e for park managers and t for agricultural

managers) represents the value for average negative impact to ecological function caused

by M~elaleuca as reported by professional land managers. In the surveys, managers were

asked to indicate how their operations had been negatively impacted in the areas of

agricultural productivity, land market value, ecological functions, and/or recreational use

as a result of~elaleuca infestations. None of the park/preserve respondents indicated

any negative impacts to the agricultural productivity or market value of their land.

Therefore, these negative impacts were not applied to any of the equations using their

information. The responses were then applied to the land use classifications and are

reflected in Table 5-2. Manager's perceptions are reflected by applying the average

negative impact percentage to the benefit gained by treatment of2~elaleuca on each land

use classification. This factor is an important addition because nobody knows the effect









M~elaleuca has on the land better than those who manage it and reflects the losses that can

be avoided by treating M~elaleuca.

Table 5-2. Average Negative Impact Values for Surveyed Land Use Classifieations.
Impact Average Average Reduction Corresponding
Reduction Park Agricultural Land Use
Managers (%) Managers (%) Classifieation
Reduced Agricultural N/A 24 Pasture, Crop,
Productivity Fruit, Nursery
Lowered Market N/A 11 Pasture, Crop,
Value Fruit, Nursery
Reduced Ecological 23 22 All Land
Function Classifieations
Diminished 23 25 Park/Preserve
Recreational Use

Finally, the equation for agricultural managers also includes the term F which is an

expansion factor used only when applying the data collected for agricultural managers to

the equation. Since only a sample of agricultural managers were surveyed, it was

necessary to expand the sample results to represent the population of agricultural

managers in South Florida. Expansion factors can be devised based on either the land

areas surveyed or the number of people surveyed. In this case it was based on the

number of managers surveyed. The population was 1 1,500 and the sample size was

2,000. Dividing the population size by the sample size yields an expansion factor of

5.75. This calculation assumes that the sample data gathered was representative of the

population.

Agricultural Land Productivity Benefits

Survey results indicated that only a small portion of the total area of2~elaleuca

treated occurs on agricultural land. However, in order to conduct a thorough analysis, as

many factors as possible are considered in calculating a benefit value. Equation 5-2 is

basically the same as the equation (5-1) used to calculate ecosystem benefits, with the










exception that the land areas reported and values applied are changed to reflect the effects

on agricultural productivity and not the ecological function and it only considers the data

gathered from agricultural managers. In essence the P variable replaces the value of the

ecological function seen in the ecosystem benefits equation and is equal to $1,034 per

acre as reported by the 2002 Agricultural Census data (USDA-NASS 2002).

Additionally, the average negative impact value, Ib, is reflective of the average

percentage reduction in agricultural productivity reported by agricultural managers

(24%), shown in Table 5-2. In this case only areas treated on agriculturally classified

land (range (x3), crop (x4), fruit (x5), or nursery (x6)) by agricultural managers are

considered since park/preserve managers reported that they managed very few acres of

land classified as being used for agricultural purposes.

Agricultural Land Market Value Benefits

A monetary value was estimated for the benefits accruing to agricultural land

market values due to the treatment of2~elaleuca on those agricultural lands. As is the

case with the previous equations (5-1 and 5-2) the variables in equation 5-3 are generally

the same; and this equation also considers only the data collected from agricultural

managers. Therefore, the areas reported for land uses Cxk, aCTOS ofhlelaleuca treated Ak,

total land management area Mk, and average negative impact value Im,(which is equal to

11% as shown in Table 5-2) are specific to agricultural managers and their perceptions of

the effects of2~elaleuca on land market values. Additionally, the variable V is equal to

$7,017 per acre, according the 2002 Agricultural Census data (USDA-NASS 2002).

Recreation Benefits

Not only does land set aside as parks or preserves play an invaluable role in

allowing vital ecological processes to be carried out, but it also provides natural areas that









allow for humans to interact with nature and gain some measure of satisfaction from

recreation. Many individuals would probably indicate that the enj oyment they gain from

outdoor recreation is not completely attributed to the ecological functions taking place on

the land, and that some measure of enj oyment is gained from the existence of the land

and the availability of the land to provide them with a place to experience the outdoors.

Therefore, it is imperative to find a way to measure the recreational value that would be

lost due to a Melaleuca infestation on a park or preserve.

Equation 5-4 shows that the rate of treatment is found by dividing Cxy by Mj then

multiplying that by Aj, and by the effective rate of treatment R (0.9). The Y variable

represents the total economic output for the year 2003 of all of the state parks and two of

the maj or national parks (Everglades National Park and Big Cypress National Preserve)

in the survey region as generated by the Money Generation Model 2 (MGM2) and is

equal to $305,670,188 (MGM2 2003). Unfortunately, due to technical difficulties with

the website that publishes this information, at the time of this publication, the economic

output of other federal parks and preserves could not be collected. It is important to note

that the inclusion of the economic outputs of these other parks would drive the

recreational benefit value higher. The equation accounts for the percentage loss in the

recreational value of park/preserve land due to M~elaeluca infestation as reported by

professional park/preserve managers, therefore, the variable Ir is equal to 23%. Finally,

the previously discussed variables are all divided by the variable L which represents the

total area of park/conservation lands in the 10 county region for 2003 (5,275,455 acres)

as reported by the Florida Natural Areas Inventory (FNAI) located at Florida State

University (FNAI 2005).









Additional Benefits

The issue of Gire danger associated with dense M~elaleuca stands has been

documented over the years. The fire danger is not only a serious concern for the Florida

ecosystem, but also for the lives and properties that are threatened when a M~elaleuca

fueled fire occurs. Fire-fighting cost estimates have been compiled through suppression

bills issued by the Florida Division of Forestry (FDOF). In 1985 and 1989 M~elaleuca

fueled fires burned nearly 12,000 acres adj acent to the Dade County Northwest well Hield

at a cost of $25,000 and $21,000, respectively, and a 1,000 acre fire in Broward County

cost approximately $10,000 (Diamond et al. 1991). Costs for municipal fire departments

are estimated to be three times that of the FDOF due to their greater manpower

requirements and equipment expenditures (Wasil and Lewis pers. comm.). These

estimates yield a per acre cost of $2 to $10 for the (FDOF) and $6 to $30 for local

municipalities. When the median of the estimated cost ranges ($6 and $16) are used, and

applied to an assumed 12,000 acre fire the calculations yield cost savings estimates

(adjusted for inflation using the GDP implicit price deflator) of $97,207 for wildland fire

control by the FDOF and $259,219 for local municipal fire departments. Table 5-3

shows that the total benefits gained from treating Melaleuca in 2003 were $31,742,298.

The benefits that apply to the areas of land reported by park/preserve managers

are ecosystem benefits, recreational values, and the benefits gained from avoidance of

increased fire damages, which are $13.14 million, $9.17 million, and $178,213,

respectively for a total of $22.49 million. The benefits of restored ecological function,

agricultural productivity, agricultural market value, and avoidance of fire damages apply

to M~elaleuca treatment areas as reported by agricultural managers in the amounts of

$236,866, $2.15 million, $6.68 million, and $178,213, respectively, and yield a total of










$9.24 million. Since there are two categories of managers being considered, the overall

avoidance of fire damages AB ($3 56,426) is divided between the two categories to yield

$178,213 for each managerial category. Finally, the total benefits are reached by adding

equations 5-1 through 5-4, along with the additional benefits of fire prevention, together

to yield:

(5-5) TB=EB + RB + APB + MVB + AB,

where TB stands for total benefits and AB stands for additional benefits due to fire

prevention.

Table 5-3. Total Benefits of2~elaleuca Control in 2003.
Benefit Value ($)
Agricultural Productivity 2, 146,228
Agricultural Land Market Value 6,675,569
Ecological Function 13,397,685
Recreational Value 703,313
Avoidance of Fire damages 356,426
Total 23,279,221

Calculation of Costs

The calculation of costs for this analysis is fairly straightforward since the cost

data were gathered by the survey. The following equations denote the different cost data

gathered :


(5-6) Cp= E Hj,
j=1

445
(5-7) Ca= F E Zk,
k= 1

1,015
(5-8) Cr= E Gi
i= 1

(5-9) Ct= (CO3 CO4)/2,









where, the variable C, represents park manager costs and is equal to the summation of the

responses (Hj) of those managers, Ca represents agricultural manager costs and is equal to

summation of those responses (Zk), the variable F represents the previously discussed

expansion factor, and C, are estimated residential costs for the year 2003 based upon the

survey responses (Gi). The methods for that estimation are discussed below. The

dependent variable Ct is the TAME Mlelaleuca budget and the variables CO3 and CO4

represent the budgets for fiscal years 2003 and 2004 for TAME M~elaleuca.

When the survey responses for the cost Eigures of park/preserve managers were

summed it was calculated that they spent $10.87 million on M~elaleuca controls during

2003. The sample of agricultural managers surveyed indicated that they spent $204,790.

As mentioned earlier, assuming that the sample of agricultural managers is representative

of the population, this cost figure can be expanded to represent the whole population of

agricultural managers. This calculation reveals that the agricultural managers in South

Florida spent an estimated $1.18 million on M~elaleuca control in 2003. Additionally, the

TAME M~elaleuca program costs were reported as $820,000 for the 2003 Eiscal year

(October 1, 2002 to September 31, 2003) and $1,010,000 for the 2004 Eiscal year

(October 1, 2003 to September 31, 2004) (Silvers pers. com.). Since these fiscal years

divide up the calendar year 2003, half of each of the budgets was taken and added

together to yield $915,000 as the estimate for the 2003 TAME M~elaleuca budget.

Cost figures were also gathered from the residential surveys. However, the cost

data collected in this survey were gathered by asking respondents to indicate what range

of money they had spent on control measures from 1990 to 2003 or since owning their

property and were not as straightforward as the costs reported by the professional










managers. For example, instead of reporting that they spent $200 in 2003, residents

indicated that they spent an amount that fell within the range of $100 to $249 since

owning their property. These responses do not allow for a specific control cost figure to

be gathered for the year 2003 and require some additional assumptions and calculations

to be made. For the sake of clarity the two issues will be addressed separately.

Since the residential survey data was a sample gathered from the population the

sample data gathered needed to be expanded to represent the population of residents in

South Florida. The survey population was 2,511,141 and the sample size was 5,001.

Dividing the population size by the sample size yields an expansion factor of 502. 13. For

the sake of using a round number the expansion factor was rounded to 500 for the

residential data. Due to the fact that respondents indicated a range of money spent on

control efforts one specific Eigure could not be calculated. Instead three separate Eigures

were calculated to reflect a range of possibilities. Specifically, low, middle, and high

range estimates were calculated to demonstrate the possible outcomes for the responses

gathered. For example, if a respondent indicated that they qualified for the categorical

cost range of zero to $50, then the low, medium, and high range possibilities for that

respondent were zero, $24.50, or $49, respectively. Every person who responded to this

question was assigned a low, medium, and high range value. Each category's outcomes

were then summed together, thus allowing three different cost scenarios to be

demonstrated for residents.

These results indicate that $6,909, $31,029, and $68,808 were the raw results

from the estimation of the low, middle, and high range residential cost scenarios,

respectively. The low, middle, and high range numbers were then expanded to $3.45









million, $15.51 million, and 34.40 million, respectively, using the expansion factor of

500, as previously discussed. Due to the fact that the maj ority of residential respondents

responded that they did not have Melaleuca on their property the assumption was made

that most of the respondents who indicated the $0 to $49 range were most likely reporting

that they had spent $0 on control measures, so this analysis uses the low cost estimates.

Additionally, the cost figures must be adjusted to represent the time frame

addressed in this analysis. A value must be calculated from the data gathered to yield the

best estimate of the cost figures for 2003. Since the data reported were for a time span of

1990 to 2003 the figures computed above were averaged out over the 14 year period to

yield an average dollar amount spent per year. Using the low, middle and high range

scenarios as discussed above, residents are estimated to have spent $246,750, $1.11

million, and $2.46 million respectively on control measures during 2003.

Table 5-4 shows that an estimated total of $13,207,863 was spent on M~elaleuca

control measures in 2003. Therefore total costs (TC) are equal to the summation of

equations 5-6 through 5-9 and is demonstrated by:

(5-10) TC= C, + Ca + Cr + Ct.

Table 5-4. Cost Data for Melaleuca Control in 2003
Group Costs ($)
Park Managers 10,866,113
Agricultural Managers 1,180,000
Residents 246,750
TAME M~elaleuca 915,000
Total 13,207,863


Calculation of the Benefit-Cost Ratio

Given the previous equations and methodology, the task of calculating a BCR that

compares agricultural productivity, agricultural land market values, ecological function,









and recreation benefits to control and program costs is now very simple. Using the

general equation:

(5-11) BCR = TB/TC,

where the variable BCR represents the benefit-cost ratio and TB and TC represent the

total benefits and total costs, respectively, all that has to be done is to enter the

appropriate values into the equation to gain an overall BCR for treating Melaleuca. As

shown in the previous tables, the total benefits gained in the areas of agricultural

productivity, agricultural land market values, ecological function, and recreational

benefits from treating Melaleuca during the year 2003 equal $23,279,221 while the total

control and program costs from the same time period amount to $13,207,863. When

these values are applied to equation 5-11, the results yield a benefit-cost ratio of 1.76.

While the total benefit-cost ratio is useful in helping to determine the overall

success or failure of a program, the discussion of the benefit-cost ratios from the

subcategories considered in this analysis can also be useful. The categories of survey

respondents had very different results for the areas occupied by M~elaleuca and the areas

treated. When the same methodologies used for the overall benefit-cost ratio are applied

to the subcategories of data, separate benefit-cost ratios can be determined for

park/preserve managers and agricultural managers. The total benefits accruing to

park/preserve managers are $14.02 million, while the total costs park/preserve managers

reported in the survey were $10.87 million, thus, yielding a benefit-cost ratio of 1.29 for

park/preserve managers.

Total benefits accruing from treatment of2~elaleuca on agricultural land are

estimated to be $9.24 million. When the cost data reported by agricultural managers are










expanded to represent the population it is estimated that the total costs were $1.18

million. Using equation 5-1 1, the calculation reveals a benefit-cost ratio of 7.83. This

number is relatively high due to the fact that agricultural lands have multiple benefits

accruing to them. Agricultural managers also reported lower costs because they have not

been treating M~elaleuca as aggressively as park managers and therefore have a greater

marginal value response at this stage of their control efforts. If agricultural managers

pursue controls more assertively, it is expected that the marginal value of the benefits

from their control efforts will diminish with the greater treatment area. While

park/preserve lands also have the multiple benefits of ecological function and recreational

value, agricultural lands have agricultural productivity and land market values as well as

ecological function accruing to them. Even though the ecological benefits that accrue to

agricultural lands are greatly diminished as compared to lands held in a natural state, the

soil and bedrock contained in them still serve some water filtration purposes, however

minimal. Therefore, agricultural lands have a relatively larger amount of benefits

accruing to them than park/preserve. While the previous statement may be true for the

purposes of this analysis, it is imperative to not jump to the conclusion that agricultural

lands are simply more valuable than park/preserve lands. There are benefits such as

existence values for parks/preserves that are not considered in this particular analysis and

would undoubtedly drive the benefits accruing in those areas higher.















CHAPTER 6
SUMMARY AND CONCLUSIONS

Summary

This thesis seeks to characterize the current state of the management of2~elaleuca

in South Florida and determine the benefits and costs of controlling M~elaleuca for the

year 2003. Previous benefit-cost analyses have primarily focused on the possible benefits

and costs associated with the unfettered spread of2~elaleuca. That kind of research was

quite useful in helping to determine if the benefits to undertake control strategies would

outweigh the costs. This analysis differs in that it seeks to assign a monetary value to the

benefits actually gained on the areas of land invaded by Melaleuca which have been

successfully treated and the costs associated with that treatment. Instead of conducting

an analysis that assumes a hypothetical best or worst case scenario, this analysis seeks to

focus on the reality of what is actually happening with the spread and treatment of

M~elaleuca in South Florida and serves to evaluate policy and management decisions

made during this program.

After consultations between UF-IFAS, USDA-ARS, and TAME M~elaleuca,

surveys were developed and mailed to professional land managers and residents in the 10

southernmost counties of Florida during the summer of 2004. The surveys for the

professional managers were sent to individuals whose management areas were classified

as park/preserve or agricultural. A wealth of information was gathered to help gain

insight into the current status of the war against M~elaleuca. The benefit-cost analysis

specifically used the data that pertained to the land use classifications of the management










area, how much M~elaleuca was on the land, the area of2~elaleuca treated, the costs

associated with the treatment, and the negative impacts to the land caused by the

M~elaleuca infestations as estimated by managers. The response rates for park/preserve

and agricultural managers were 32% and 22%, respectively.

The responses from park/preserve managers revealed that 619,317 acres of

M~elaleuca inhabited their management areas, while they treated a total of 84,740 acres

during 2003. Based on the fact that control strategies are not completely effective, a 90%

rate of effective removal was applied to the treatment areas reported by park/preserve

managers to yield the estimated area of Melaleuca killed as 76,265 acres. The total costs

associated with these control methods were reported as $10.9 million. The park/preserve

managers felt that M~elaleuca impaired the ecological function and recreational use of the

land they managed by an average of 23%.

Agricultural managers indicated that a total of 2, 134 acres of~elaleuca occurred

on their land and that they treated approximately 1,991 acres during the year 2003. When

the assumed effective rate of treatment is used it is estimated that approximately 1,701

acres of Melaleuca were killed on agricultural lands during 2003. The total costs

associated with these treatments were approximately $204,790. It should be noted that

these figures collected from the sample of agricultural managers were expanded to reflect

the population for the calculation of the benefit cost ratio(s). The expanded figures

indicate that agricultural managers had an estimated total of 12,271 acres of2~elaleuca

occupying their land, while they treated an estimated 10,868 acres at an estimated cost of

$1,180,000 during 2003. Finally, the agricultural managers reported that the agricultural










productivity, market value, and ecological function of their land had been reduced by an

average of 24 percent, 11 percent, and 22 percent, respectively.

The maj ority of the data gathered by the residential survey was directed at

gathering information related to the awareness and perceptions of2~elaleuca by the

residents and therefore much of it was not used in this benefit-cost analysis. However,

the cost data collected from the residents was used. Residents had the lowest survey

response rate at 20 percent. Based on the data collected and the methods described in the

previous chapter, it was estimated that the residents of South Florida spent an estimated

$246,750 on Melaleuca control/removal in 2003.

Using the information gathered from the mail surveys and other relevant data

sources it was determined that the benefit-cost ratio for M~elaleuca control in the year

2003 was 1.76. The benefit portion of the ratio was computed by assessing monetary

values for the benefits that were gained due to the restored ecological function of

agricultural and park/preserve land, agricultural productivity and market value of

agricultural land, and the recreational use of park/preserve lands where M~elaleuca

controls had been implemented. The additional benefit of avoidance of costs connected

with M~elaleuca fueled fire control was also considered in the benefit equation. The costs

were derived from the residential and professional survey data along with the TAME

M~elaleuca program costs which include the costs associated with this research.

Conclusions, Implications, and Policy Recommendations

Based upon the results of the surveys it is quite apparent that the vast maj ority of

M~elaleuca control is still taking place on public land in South Florida. As stated in the

introduction of this thesis, this phenomenon is most likely due to the fact that a legal

mandate requires public agencies to remove invasive plants from their management areas.









It may be necessary for the legislature to make the current laws addressing the general

public more stringent so as to induce a greater number of private land managers and

homeowners to implement M~elaleuca controls on their properties. While making the

laws stricter is a step in the right direction, it will also be necessary for the lawmakers to

assign specific penalties for those in violation of the law and require a uniform

enforcement of the laws and penalties. This would require increased presence by the

enforcement agencies and would certainly require a greater amount of time and effort

from those agencies. A requirement similar to those municipalities that call for new

construction sites to have Melaleuca trees removed from the property before a certificate

of occupancy can be issued may be a useful tool in inducing Melaleuca removal.

The results of the benefit-cost analysis support the earlier hypothesis made that this

analysis would yield a benefit-cost ratio higher than one. When the benefits from

M~elaleuca control realized on park/preserve and agricultural land are compared to the

costs incurred by those land managers and private residents the analysis indicates that the

benefits are almost two times greater than the costs. It is important to keep in mind that

this is not even considering benefits that may be accruing to the private homeowners in

South Florida and would only serve to increase the benefits. Given the resulting cost-

benefit ratio of 1.76, it can be said that the current policy requiring M~elaleuca control is

providing a benefit to society in the year 2003. It is interesting to note that due to the

compound effect of having multiple values tied to their land (i.e.-the values gained from

the ecological functions, the actual production of agricultural commodities as well as the

market value of the land) this analysis indicates that agricultural lands have a higher

benefit-cost ratio than park/preserve lands for treating M~elaleuca (7.83 vs. 1.29). Even









without considering the benefits accruing to agricultural land market values, the ratio is

still greater for agricultural lands than park/preserve lands (2.17 vs. 1.29). Therefore it is

recommended that policymakers and public agencies continue to at least maintain the

current levels of funding and control efforts for M~elaleuca reduction. Not only should

they continue to maintain the current levels of funding, but they should also consider

increasing funds to help specifically target agricultural managers to persuade them to

control M~elaleuca on their property. This would serve to help solve the problem of

having M~elaleuca spread around private lands, while it is being controlled on public

lands, and would also help avoid cross contamination from the infested areas to the areas

under control.

A maj ority of residents who responded to the survey questions aimed at

determining their awareness of2~elaleuca indicated that they knew that M~elaleuca was

not native to Florida and that they knew non-native plants could be harmful (71% and

89%, respectively). However, when the residents were later asked to indicate if

M~elaleuca effected their enj oyment of the outdoors 77% of those who responded to the

question indicated that it did not. When residents were asked to indicate if they felt that

M~elaleuca negatively affected their property value 95% of those responding to the

question indicated that they felt it did not. There seems to be a gap between what people

know about M~elaleuca and how that knowledge affects their desire to take the actions

necessary to control it. According to the survey data the main sources that provide

information on M~elaleuca for residents were newspapers and local/national news (59%

and 47% of residents who responded to the question, respectively). These may be the

outlets that policy makers, environmental action groups, and public agencies should




Full Text

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SOCIO-ECONOMIC IMPACTS OF CONTROLLING Melaleuca IN SOUTH FLORIDA By KATHERINE FINN A THESIS PRESENTED TO THE GRADUATE SCHOOL OF THE UNIVERSITY OF FLOR IDA IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE UNIVERSITY OF FLORIDA 2006

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Copyright 2006 by Katherine Finn

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For Jeffrey

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iv ACKNOWLEDGMENTS I would like to start off by thanking my hus band Jeffrey Finn who has traveled this journey with me and been the best partner I co uld have ever hoped for. I especially thank him for the encouragement and perspectiv e that he has offered me along the way. I wish to express eternal thanks to my Mom, Gena Carte, for her never ending support and for always telling me that I can do whatever I set my mind to, even when it feels like it is impossible. I wish to express my deepest gratitude to my Dad, Jerry Carter, for showing me the value of hard work, fostering my appreciati on for nature, and for teaching me to hunt and fish better than most men. My deepest gratitude goes out to my committee members Dr. Alan Hodges, Dr. Donna Lee, and Dr. Mike Olexa for their guidance along the way. I am especially grateful to Dr. Hodges who worked with me on a day to day basis and taught me so much. His patience and dedication are appr eciated more than he will ever know. I wish to offer special tha nks to the USDA-ARS for fundi ng this research. I would like to express my gratitude to Francois La roche of the South Florida Water Management District and the members of th e TAME Melaleuca team, especially Cressida Silvers, Paul Pratt, and Amy Ferriter for always being will ing to answer “just one more question.” Many thanks go to Sharon Wallace of the S outh Florida Water Management District, Debbie Gillet of the Southwest Florida Wa ter Management District, Chris Wassil and Gary Lewis with the Florida Division of Forestry, and Gail Baxley with the Florida

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v Department of Environmental Protection’s Offi ce of Park Planning for sharing their data, insight, and experiences with me. Thanks go to Carol Fountain for all of her formatting expertise. I would like to express my th anks to all of the friends I have made in graduate school. They are the reason I will look back on this whole experience and have pleasant memories filled with smiles and laughter Thanks go to the best study group around, Erika Knight, Jamille Palacios, Anne Jones, and Jennie Varela; the first year core would have been impossible without them. I am especi ally grateful for the f act that at the first day of orientation I sat next to Erika Knight and struck up a conversation; her friendship has been priceless Special thanks go to Damian Ad ams for being a great colleague and wonderful friend. Thanks go to comedian s Justin Taylor ( GO RACERS!) and Athur Mabiso for always offering an easy laugh and “ Respect .” Thanks go to Annie Hildebrand for offering me big beautiful smiles when I needed them the most. Special thanks go to my friend Beth-Anne Blue for all of her wisdom, guidance, and support and especially for reminding me that I could do this. I would like to acknowledge th e close family members who are no longer here with me to share in the joy of this accomplis hment: my Grandparents Pepa and Grammie (Red and Mary) Carter, Gov (Gran-Daddy Victor B. Carte, Jr.), a nd step-father Scott Whidden. I wish to thank them for all of the love and support they offered during their time here. Last, but certainly not least, I offer my thanks to God, for with Him everything is possible.

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vi TABLE OF CONTENTS page ACKNOWLEDGMENTS.................................................................................................iv LIST OF TABLES.............................................................................................................ix LIST OF FIGURES...........................................................................................................xi ABSTRACT......................................................................................................................x ii CHAPTER 1 INTRODUCTION........................................................................................................1 Origins, Introduction, and Invasion..............................................................................2 The War Against Melaleuca .........................................................................................3 Problem Statement........................................................................................................5 Public Lands vs. Private Lands.....................................................................................6 Hypotheses & Parameters Estimated............................................................................7 Research Objectives......................................................................................................7 2 LITERATURE REVIEW.............................................................................................9 Introduction to Benefit-Cost Analysis..........................................................................9 Formal Theoretical Framework Behind BCA............................................................11 Benefit Cost Analysis and Social Welfare Theory.....................................................13 Individual Welfare Changes................................................................................13 Social Welfare Changes......................................................................................16 Benefit-Cost Analysis in Practice...............................................................................17 Use of Mail Surveys...................................................................................................19 The Contingent Valuation Method (CVM)................................................................21 Previous Research on the Economic Impacts of Melaleuca .......................................25 3 SURVEY DESIGN, CONTEN T, AND ADMINISTRATION..................................27 Survey Methods..........................................................................................................27 Survey Study Area, Target Populations, and Sampling.............................................27 Survey Content...........................................................................................................28 Residential Survey...............................................................................................29 Professional Land Manager Survey.....................................................................31 Survey Administration................................................................................................33

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vii 4 SURVEY RESULTS..................................................................................................34 Results for Professional Managers.............................................................................34 Land Ownership Status........................................................................................34 Land Use..............................................................................................................34 Factors Affecting Land Management..................................................................36 Area Occupied By Invasive Plants and Area Treated.........................................39 Methods Used for Treating Melaleuca ................................................................41 Barriers to Controlling Melaleuca .......................................................................46 Sources and Usefulness of Information for Melaleuca Control..........................47 Costs for Melaleuca Control...............................................................................50 Impacts of Melaleuca ..........................................................................................52 Annual Income or Budget and Compar ison of Reported Melaleuca Control Expenses..........................................................................................................54 Results for Residents..................................................................................................56 Invasive Plant Awareness....................................................................................56 Amount of Melaleuca on Property......................................................................56 Use of Control Methods for Melaleuca ...............................................................57 Barriers to Controlling Melaleuca .......................................................................58 Information Sources for Melaleuca Control........................................................59 Expenses for Melaleuca Control.........................................................................60 Impacts on Property Values.................................................................................60 Willingness to Pay for Melaleuca Removal/Eradication....................................61 Impacts of Melaleuca on Outdoor Enjoyment....................................................62 Willingness to Pay to Reduce Melaleuca in Outdoor Activity Areas.................63 Respondent Demographics..................................................................................64 5 BENEFIT COST ANALYSIS....................................................................................67 Calculation of Benefits...............................................................................................68 Ecosystem Benefits.............................................................................................70 Agricultural Land Productivity Benefits.............................................................73 Agricultural Land Market Value Benefits...........................................................74 Recreation Benefits.............................................................................................74 Additional Benefits..............................................................................................76 Calculation of Costs....................................................................................................77 Calculation of the Be nefit-Cost Ratio.........................................................................80 6 SUMMARY AND CONCLUSIONS.........................................................................83 Summary.....................................................................................................................83 Conclusions, Implications, and Policy Recommendations.........................................85 Recommendations for Future Work...........................................................................88

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viii APPENDIX A MELALEUCA MANAGEMENT SURV EY OF PROFESSIONAL LAND MANAGERS..............................................................................................................90 B MELALEUCA MANAGEMENT SURVEY OF RESIDENTIAL PROPERTIES...99 LIST OF REFERENCES.................................................................................................113 BIOGRAPHICAL SKETCH...........................................................................................117

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ix LIST OF TABLES Table page 4-1 Land area managed by surveyed profe ssional land managers in Florida.................35 4-2 Land use types and areas managed by pr ofessional land managers in Florida........36 4-3 Factors influencing management deci sions by professional land managers in Florida......................................................................................................................38 4-4 Land area infested with and treated for invasive species by professional managers in Florida..................................................................................................41 4-5 Methods used for treatment of Melaleuca by professional land managers in Florida......................................................................................................................43 4-6 Number of professional managers us ing various control methods and area of Melaleuca treated in Florida, 2003 and 1990-2003.................................................44 4-7 Intentions for future use of various Melaleuca control methods by professional managers in Florida..................................................................................................45 4-8 Requests for more information on Melaleuca control methods by professional managers in Florida..................................................................................................45 4-9 Barriers to controlling Melaleuca by professional managers...................................47 4-10 Information sources and types of medi a used by professional land managers in Florida......................................................................................................................48 4-11 Usefulness of information received by professional land managers in South Florida......................................................................................................................50 4-12 Costs for Melaleuca control reported by professiona l land managers in Florida, 2003..........................................................................................................................5 1 4-13 Expenses for special equipment for Melaleuca control by professional managers in Florida..................................................................................................................51 4-14 Melaleuca treatment cost trends reported by professional land managers in Florida......................................................................................................................52

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x 4-15 Negative impacts of Melaleuca reported by professional land managers in Florida......................................................................................................................53 4-16 Reduction in utility due to Melaleuca infestation reported by professional land managers...................................................................................................................54 4-17 Annual income or budget for land mana gement by south Florida professional managers, 2003.........................................................................................................55 4-18 Awareness of Melaleuca and invasive plants by Florida residents..........................56 4-19 Amount of Melaleuca on property of Florida residents...........................................57 4-20 Methods used for Melaleuca control by Florida resident s, and interest in more information about control methods..........................................................................57 4-21 Barriers to controlling Melaleuca by Florida residents............................................58 4-22 Sources of information on Melaleuca received by Florida residents.......................59 4-23 Expenses for Melaleuca control by Flor ida residents, 2003..................................60 4-24 Negative effect of Melaleuca on property value of Florida residents......................61 4-25 Willingness to pay for removal of Melaleuca from property by Fl orida residents..62 4-26 Days of annual outdoor recreation activ ity reported by south Florida residents, 2003..........................................................................................................................6 3 4-27 Effect of Melaleuca on outdoor enjoyment by Florida residents.............................63 4-28 Willingness to pay per visit to reduce Melaleuca in recreational areas by Florida residents....................................................................................................................64 4-29 Demographics characteristics of su rveyed south Florida residents, 2003...............66 5-1 Ecosystem Values for Surveyed Land Use Classifications......................................72 5-2 Average Negative Impact Values fo r Surveyed Land Use Classifications..............73 5-3 Total Benefits of Melaleuca Control in 2003...........................................................77

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xi LIST OF FIGURES Figure page 4-1 Average weighting of factors influe ncing management by professional land managers...................................................................................................................39 4-2 Usefulness rating of information sources and media by professional land managers in Florida..................................................................................................49

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xii Abstract of Thesis Presen ted to the Graduate School of the University of Florida in Partial Fulfillment of the Requirements for the Degree of Master of Science SOCIO-ECONOMIC IMPACTS OF CONTROLLING Melaleuca IN SOUTH FLORIDA By Katherine Finn August 2006 Chair: Donna Lee Major Department: Food and Resource Economics Melaleuca quinquenervia commonly referred to as Melaleuca, was introduced to Florida in the late 1800s and ha s flourished in the state since its introduction. In the late 1980s and early 1990s efforts to eradicate/control Melaleuca began in earnest. The Areawide Management Evaluation of Melaleuca (TAME) program was created specifically to research and address the problems and unique situations associated with Melaleuca control. Public agencies in Florida spent an estimated $25 million on control efforts from 1989 to 1999 and have succeeded in reducing the area it covers; however, private landholders have been less aggressive in its removal. Despite the control efforts on public lands, the lack of treatme nt on private lands has allowed Melaleuca to spread in many areas and resulted in no net loss of the acreage covered. Melaleuca causes a reduction in ecological function, agricultura l productivity, and recreational use value of lands occupied. In order to document the current management and socio-economic impacts of this species surveys were mailed to 2,000 agricultural

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xiii landowners, 285 park/preserve managers, and 5,000 randomly selected residents in the ten southernmost counties of Florida in 2004. Survey results revealed that Melaleuca covered more than 620,000 acres of land and that professional managers (both park /preserve and agricultural) had treated approximately 86,731 acres during 2003. A benef it-cost analysis was conducted for the areas controlled in 2003. The benefits were estimated based on the values for restored ecological function of agricultural and park /preserve land, agricultural productivity and market value of agricultural land, the recr eational use of park/preserve lands where Melaleuca controls had been implemented, and avoidance of costs connected with Melaleuca fueled fire control. Total benefits amounted to $23.3 million. The costs were derived from the residential and profe ssional survey data along with TAME Melaleuca program costs which include the costs associ ated with this research. Total costs amounted to $13.2 million The resulting benefit-cost ratio (1.76) indicates that the benefits of Melaleuca removal were significantly greater than the co sts, and that control efforts provided a net social benefit to society in the year 2003. Therefore, it is recommended that the policy stay in effect until the benef its no longer outweigh the costs.

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1 CHAPTER 1 INTRODUCTION An invasive species as defined by th e 1999 Executive Order 13112 is “an alien species whose introduction does or is likely to cause economic or environmental harm or harm to human health.” I nvasive species have affected many, if not most, countries around the world in some way. In some cases alien species are pur posefully introduced for bona fide reasons; case in point, the now infamous Kudzu used for ornamental purposes, erosion control, and livestock fora ge. In other situa tions a species is inadvertently introduced through increased globa l travel, such as the Brown Tree Snake’s introduction to Guam. Some alien species are introduced and remain rather innocuous throughout their lifespan. However, ofte n times they can cause devastating and irreversible consequences, such as the al most total annihilatio n of Guam’s songbird population and Kudzu’s prolific spread throughout the Sout heast and Hawai’i to now cover several million acres of land. Every year, a growing numb er of individuals make Florida their new home. However, this phenomenon is not limited to hum ans. Plants, animals, and pathogens also find ways to make this accommodating sub-tr opical land their home as well. Florida’s mild winters and warm wet summers are quite hospitable to many different species and allow non-native residents to become resident aliens. One especially destructive alien invader that has now become an invasive species is the highly problematic tree commonly known as Melaleuca ( Melaleuca quinquenervia ).

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2 Origins, Introduction, and Invasion Melaleuca also had a rather innocent beginning in Florida. It is thought to have been introduced in Florida by Royal Palm Nurseries in Manatee County around 1887. The tree was popularized by nurseries and gained greater recognition due to its ability to thrive in many environments and rapidly provide shade and windbreaks for home owners (Serbesoff-King 2003). It was subsequently pl anted in swampy areas to help dry up the standing water so developers could build to meet the demand of the booming South Florida population (Laroche and McKim 2004). This notion has now become the subject of much debate amongst scholars. While so me scientists adhere to the belief that Melaleuca consumes more water than native vegeta tion, others argue th at their research indicates that it does not use any more water than the average plant. In 1941, Florida populations of Melaleuca from Lake Okeechobee southward began to increase as the US Army Corps of Engineers (USACE) planted the trees along levees and spoil islands for erosion control (Stocker a nd Sanders 1981). This fast growing species has now become establishe d, and has spread much more quickly in Florida than in Australia, and competes with many native plant species (Rayamajhi et al. 2002). Due to its rapid grow th and reproduction rates, Melaleuca may completely dominate landscapes that it invades, thus decreasing biodiversity and precluding the growth of native vegetation (Schmitz and Hofs tetter 1999). Studies show that patches of Melaleuca can spread to dominate one square mi le of land in only 25 years (Laroche and Ferriter 1992). Melaleuca may also increase wildfire danger, because the dense stands burn with greater intensity making fire c ontrol more difficult (Diamond et al. 1991).

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3 The War Against Melaleuca While this tree has been on Florida soil for more than 100 years, its control was not seriously pursued in the state until the late1980’s. This is due, in part, to the movement to restore the Everglades During the 1990’s, the fram ework leading up to the Comprehensive Everglades Restoration Plan (CERP) began to be developed. After the foundation was laid by the previous Water Resources Deve lopment Acts of 1992 and 1996 President Clinton signed the Water Resources Development Act of 2000, Section 601 which authorized the CERP. When it became clear that invasive species would only serve to thwart the goals of CERP which are restoring, preserving, and protecting South Florida’s ecosystem, measures were taken to address the growing pr oblem. Specifically, the Melaleuca Eradication and Other Exotic Plan ts project, within the CERP, was designed to address exotic and invasive sp ecies management and control in Southern Florida (CERP 2004). Recognizing the need to take aggressi ve action against invasive species, in 1993 the Florida legi slature enacted statutes that require agencies such as the Florida Department of Environmental Protec tion Bureau of Invasive Plant Management (FDEP-BIPM) to investigate methods of control for Melaleuca and to implement those control methods within thei r jurisdiction (FS 369.252). Unde r current state law it is illegal to sell, transport, colle ct, cultivate or possess any plan t, including any part or seed of the species Melaleuca quinquenervia without a permit from th e FDEP or the Florida Department of Agriculture and C onsumer Services (FDACS) (FS 369.251). In 1997 the legislature directed the Bureau of Invasive Plant Management (BIPM) to build a program to bring exotic upland species under maintenance control, by enacting Florida statute 369.22. The statute detail s that a maintenance control program is “a method for the control of non-indigenous aqua tic plants in which control techniques are

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4 utilized in a coordinated manner on a conti nuous basis in order to maintain the plant population at the lowest feasible level as determined by the department” (FS 369.22 p.1). The 1993 Florida legislature also set aside an annual budget of $1 million to the FDEP specifically for Melaleuca control. The FDEP took the award from the legislature and then entered into a cost-sharing program (called the Melaleuca Program) with the South Florida Water Management District (SFWMD) in which they match that award dollar for dollar (BIPM 2003.) The goal of the Melaleuca program is to control Melaeluca on all SFWMD land and to maintain the lowest po ssible infestation rates while minimizing impacts to non-target plant species. In orde r to prevent the wider spread of the plant, outlying lesser infested areas are treated fi rst according to a quar antine strategy (BIPM 2003). The goal of the FDEP is to reduce infest ations of upland invasi ve exotic plants on public lands by 25 percent by the year 2010 based on the estimated 1995 level of infestation of 1.5 million acres (BIPM 2003). It should be noted that this estimated area is for all upland invasive species and not just Melaleuca Additionally, The Areawide Ma nagement Evaluation of Melaleuca (TAME Melaleuca or TAME) has been established under th e auspices of the USDA Agricultural Research Service (ARS) Areawide Pest Ma nagement initiative to demonstrate the efficacy of an integrated approach that can be applied to invaded areas for control of Melaleuca This group has proceeded to implemen t the control recommendations of the Melaleuca Task Force as enumerated in the Florida Exotic Pest Plant Council’s (FLEPPC’s) Melaleuca Management Plan (Pratt and Ferriter 2001). TAME has subsequently teamed up with the Food and Resource Economics Department (FRED) at the University of Florida’s Institute of F ood and Agricultural Sciences (UF-IFAS) to

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5 conduct this research into the socio-economic impacts of Melaleuca in South Florida. Estimates place the coverage of Melaleuca at anywhere from 200,000 to 500,000 acres of land in South Florida. From 1989-1999 Flor ida agencies have spent about $25 million on its control and have succeeded in reduci ng the area it covers on public land by about 100,000 acres (Pratt and Ferriter 2001). Problem Statement A major problem with the spread of Melaleuca is that it causes a reduction of economically viable uplands and ecologically sensitive wetland areas. A general estimate of the value of environmenta l and economic services prov ided by wetlands is $14,785 per hectare per year (Costanza et al. 1997). A ssuming minimal losses of one percent, and a current infestation of 200,000 hectares, the di minished value would be almost $30 million per year. Farmers and ranchers are losing valuable grazing and crop land while natural areas such as parks/preserves are losing natura l habitats, which in turn affect plant and animal diversity. Melaleuca invades utility easements such as power lines, canals, and other waterways, thus impairing their use, and often makes costly tree removal necessary to maintain the use of these service areas. It has been projected that the unfettered spread of this plant would severely limit the use of parks and recr eational areas by tourists and residents causing a negative impact to the Florida economy at $160 million annually (Diamond et al. 1991). Additional reports s how that by the year 2010 an estimated $1.76 billion in damages would be caused due to the various negative impacts it has on recreation, ecotourism, fires, and loss of endangered species (Balciunas and Center 1991). The majority of the information gathered through mail survey s focus on elements traditionally used in determining the extent to which Melaleuca covered land, how much

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6 was being treated, what methods were being us ed to treat it, and the costs incurred for those treatments. However, at the time this research was being carried out it was not readily apparent that much was known about the negative effects caused by Melaleuca infestation. To help bridge the apparent information gap, additional data need to be collected to determine how indivi duals perceived the effects that Melaleuca infestations have on ecological function, agri cultural productivity, land mark et values, the use of land for recreation and enjoyment of the outdoors. Public Lands vs. Private Lands For many years, the slogan of “Florida Stat e Parks: The Real Florida” was used to help promote tourism within the State’s park system. The general goal of having these parks is to allow visitors to see Florida’s natural state where it has been left relatively untouched by human hands. However, inva sive species, which often completely dominate native flora and fauna, thwart the goal of preserving the “real Florida.” In order to meet this goal, non-native species must be removed. This need has been realized by managers of the public lands and therefore c ontrol has been concentrated on these lands. However, while its removal is a mandat e for public agencies, one of the major obstacles facing the success of Melaleuca control is the fact that private individuals often implement few or no controls. While it is te chnically illegal for pr ivate individuals to possess Melaleuca very little is actually being done to force them to remove it from their private property (with the excep tion of a few pro-active municipa lities). This presents the conundrum of falling infestation rates on pub lic lands, while infestations flourish on private lands and often cause cross-contaminatio n in areas that have been treated (such as public lands) or areas that have not yet been infested. The efficiency of treatment is greatly reduced if public land managers continue to treat and kill Melaleuca while

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7 private individuals allow for outlying infestat ions to spread. A comprehensive strategy for inducing private citizens to control Melaleuca is necessary if there is to be any chance of gaining the upper hand in the war against its spread. Hypotheses & Parameters Estimated The issues surrounding the impacts that inva sive species have on society are very broad and far reaching. Previ ous research on invasive species has mainly focused on the biological characteristics of th e plants. Current research has started to focus on what kinds of monetary and non-monetary impact s these invaders are having on the economy and society as a whole. This research seek s to focus more on the socio-economic impact that Melaleuca has had on Florida in the regi on south of Lake Okeechobee. The hypothesis that will be tested is that this analysis will yi eld a Benefit Cost Ratio (BCR) for treating Melaleuca that is greater than unity (1). Parameters that will be estimated by this research are: What are the impacts/costs of reducing Melaleuca infestations in South Florida? What factors influence the choice of control method (or lack thereof)? How much money is currently spent on Melaleuca controls? How much money would homeowners be willing to spend to remove Melaleuca from their property? How much money would residents be willing to spend to reduce Melaleuca in the places where they engage in outdoor recreational activities? What is the BCR for controlling Melaleuca ? Research Objectives The general objective of this research is to determine the economic impact that Melaleuca has had on professional land managers and residents in South Florida, along with evaluating the socio-economic impact of its control. This will require gathering

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8 information including (but not limited to) wh ich control strategies are currently being used, how much they cost, and what area is curr ently being treated. It is hoped that this research will shed some new light on why individuals are more or less likely to implement control measures. Then policy makers and implementers can custom tailor outreach and education program s to increase the area of Melaleuca being treated. A specific objective of this research is to measure the benefits and costs associated with the treatment of Melaleuca infestations for the year 2003. Trying to eradicate a species that has such a stronghold on a la rge area of ecologi cally sensitive and economically valuable land is not cheap. A large amount of money has been and will continue to be spent if this program is to be considered su ccessful. It is imperative to determine whether the benefits of controlling this invasive species outweigh the costs. As a matter of public policy, th e resources being allocated to this program should provide a net benefit to society. A benefit-cost analysis will provide information to determine if the resources being allocated to this fight are economically justified.

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9 CHAPTER 2 LITERATURE REVIEW The legislative aim of controlling Melaleuca has many far reaching implications for society. Current research is beginning to focus more on the socio-economic impact of invasive plants. A combination of tools is necessary to fully evaluate the socio-economic affects of controlling Melaleuca Among the tools available, this study employs the use of Benefit-Cost Analysis (BCA) and Con tingent Valuation (CV) through mail survey administration. Introduction to Benefit-Cost Analysis Every day new projects and policies are proposed in both the public and private sectors. Decision makers are then faced with the daunting task of deciding which of the myriad projects or policies will help to ach ieve their desired goal or end result. Over time, BCA has been used extensively to help determine the economic viability of legislation and investment pr ojects. Since the 1930s BCA has been used by many U.S. agencies to determine if the benefits of thei r policies outweigh the costs to society (Prest and Turvey 1965). Many past U.S. Presid ential administrations have recognized the value that this type of anal ysis can provide by attempting to clearly delineate the costs and benefits of a proposed policy/course of action (Whittington and Grubb 1984). Through Executive Order 12291 signed on Februa ry 17, 1981, President Ronald Reagan sought to standardize and make permanent the requirement for federal agencies to conduct BCA on all “major” regulations.

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10 Due to the fact that some policies and regulations can result in “win-lose” situations, analysis needs to identify the wi nners and the losers and exactly how those groups will be affected. Sassone and Schaffer (1978) point out that the need for careful analysis is especially important in large scale public projects with irreversible consequences. A thorough anal ysis can help to identify nor mally “unforeseen” costs that tend to creep up during the life of a project. Policy makers or project managers can then develop strategies and contingency plans that will help to mitigate these circumstances. There are many definitions on what constitutes a BCA. However, there are generally some key similarities between the de finitions of the process. One description suggests that BCA is a “generic term embr acing a wide range of evaluative procedures which lead to a statement assessing costs and benefits relative to project alternatives” (Sassone and Schaffer 1978, p.3). Another more specific definition states that it is “a process of identifying, measuri ng, and comparing the social benefits and costs of an investment project or program” (Campbe ll and Brown 2003, p. 1). BCA has been described as a procedure for “measuring the ga ins and losses to individuals, using money as the measuring rod of those gains and losse s and aggregating the money valuations of the gains and losses of the individuals and expr essing them as net social gains or losses” (Pearce 1983, p. 3). An integral part of a BCA is the identific ation of all relevant costs and benefits. Another important step is th e quantification of those cost s and benefits (Sassone and Schaffer 1978). It is important to note that these costs and benef its are analyzed by a “with” and “without” comparison. Specifically, th e analysis of the pr oject seeks to assign a value to the costs and benefits that occur “with” the project and compare them to the

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11 state of the world as it w ould exist “without” the project (Gittinger 1982). This is different from considering the state of th e world “before” the project and “after” its implementation. If a “before/after” comparis on is used it neglects the change that would take place without the project and allows for an erred account of the benefits that can be ascribed to the project/policy. Campbell and Brown (2003) also point out that the important concept of opportunity cost beco mes a factor in the “with and without” comparison. Without the project, scarce res ources such as land, labor, and capital could be designated to other uses. With the projec t, the opportunities to use those same scarce resources for some other beneficial purpose are foregone. Each possible outcome offers a particular value to society. After comple ting a thorough analysis of the two possible outcomes (with or without the project) and determining the costs and benefits of the projects the analyst can determine if the benefits exceed the costs. If this is the case, then the project would be recomme nded to the policy maker. Formal Theoretical Framework Behind BCA Using BCA to assign a moneta ry value to the effects a project will have relies upon two key assumptions. The first is that the so cial value of a project is a summation of the values of the project to indi vidual members of society. The second is that the value of a project to an individual is equal to thei r (fully informed) willi ngness-to-pay (WTP) for the project (Sassone and Schaffer 1978). Willingness-to-pay is the specific expression of the value an individual assigns to a commodity or service. This leads to an essential conclusion in microeconomics that for any given price of a good, rational individuals aiming to increase their state of well-being as much as possible, will purchase a number of units of that good so that at the margi n, their willingness to pay for that good just equals its price. Therefore, if an effect of a project were a small increase or decrease in

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12 the number of units of a good accessible to an individual for consumption, that increase or decrease has a social value equal to the number of units concerned multiplied by the market price (Sassone and Schaffer 1978). The formal BCA theoretical framework, reliant upon welfare economics, set forth by Sassone and Schaffer (1978) in dicates that a state (of the world) S is a particular distribution of utility among the individual memb ers of society; specifically demonstrated by: (2-1) S = (U1, U2, Â…, Uj, Â…, UN), for a society made up of N members. A well defined project, through intentional act ions, will advance society from the current state of status quo, So to an alternative state of SÂ’. Vj is the value of a project to an individual j, and is their maximum WTP amount to have the project implemented (when they are in favor of the project), and when th ey do not favor the project, it is the negative of the minimum amount of their willingness-toaccept as payment in order to remain just as well off in SÂ’ as in So. If the project does not alter individual jÂ’s utility then their compensating variation, Vj = 0. Therefore, the social value of a project is the summation of the individualsÂ’ willingness to pay, identified by Vj. Actually acquiring each individualÂ’s willingn ess to pay can be problematic in two ways (Sassone and Schaffer 1978). First, e ach individual would ha ve to have perfect knowledge of every aspect of the project. The impracticality of this is readily apparent due to the fact that many of the people act ually involved with the project are often not fully aware of every detail. The second difficu lty lies within the fact that individuals are often unable or have difficulty in defining th eir own compensating variation by stating an

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13 arbitrary number. The aforementioned reasons lead to the sugges tion that some other form of acquiring the individua ls compensating variations is necessary. Sassone and Schaffer (1978) suggest that th is information is best gleaned by using interviews or questionnaires. Benefit Cost Analysis and Social Welfare Theory As suggested in the previous section, welfare economics prov ides a theoretical basis for BCA. Although BCA did not original ly evolve from welf are economics it has come to rely upon the foundation that welfar e economics creates (Cohn 2003). It has been suggested that BCA is an application of welfare economics (Sassone and Schaffer 1978). While Sassone and Schaffer (1978) provide a very general introductory framework for BCA (as shown in the previous section), Cohn (2003) provides a more indepth analysis into it s theoretical basis. Individual Welfare Changes Following the assumption that each individual x1, x2, Â…, xn has n goods and services (including savings) available to him or her, a utility function of Ui for the ith individual is expressed as: (2-2) Ui = U(xi1, xi2, Â…, xin). If a new government policy is introduced that has an impact on some of the quantities of goods and services that individual i consumes, the change in utility ensuing from a change in the quantity of the jth good or service is defined as: (2-3) Ui = ( MUij) xij. MU ij describes individual i Â’s marginal utility for an added unit of j and xij is the change in the quantity of good or service j that the individua l receives. From the microeconomic

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14 principle stated earlier, it is known that an individual will select goods and services so that the marginal utility for any good, j would be equal to the price of the good, pj, multiplied by the individual’s marginal utility of income ( MUYi), given as the following: (2-4) MUij = ( MUYi)pj. By substituting equation (2-4) into equa tion (2-3), the following results: (2-5) Ui = ( MUYi)pj xij. The change in the income of individual i due to the change in the quantities of goods and services brought about by the new gove rnment policy is found in the term pjxij. Finally, the change in individual i ’s utility is equal to the change in income weighted by the value of the individual’s marginal utility of income. Due to the fact that a new government policy will affect many people it is important to know what change in social welf are is due to the new policy. This can be found by determining the changes in the individual utilities of m persons affected by the policy using the social welfare function: (2-6) W = W (U1, U2, U3, …, Um), where W represents social welfare. Taking equa tion (2-6) into consid eration, a change in social welfare is noted as: (2-7) W = V = ( U1, U2, U3, …, Um), where W represents the change in social welfare. Keeping in mind that Arrow’s Theorem questions the possibility of deriving a social welfare function at all, Cohn (2003) s uggests that the real issue is whether an “acceptable” function can be developed. One major stumbling block for this is the interpersonal comparison of utility, which so me economists argue condemn BCA. While

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15 there are cases when various forms of so cial welfare functions do not provide an acceptable social choice, the argument can be ma de that a flawed social welfare function is better than none at all. Therefore, equation (2-7) can be differentiated to the form of: (2-8) d W = ( W / Ui)d Ui, to obtain: (2-9) W = ( MSU i) Ui, where MSUi demonstrates the change in social we lfare arising out of the change in the utility of the i th individual. MSUi is also known as the “distr ibutional weight” given to individual i ’s utility. In other words, it reflects th e societal value of the changes in the individual’s level of utility. Substituting equation (2-3) into equati on (2-9), the following is obtained: (2-10) W = ( MUYi) ( MSUi)pj xij. This equation illustrates the changes that oc cur in social welfare due to a new public policy that influences the qua ntities of goods and services available to individuals in society. It is the sum of the fluctuations in effectiv e income for every individual weighted by the product of the marginal utility of income of the individual i ( MUYi), and the changes in the quantities of goods and services as a result of the new policy, pj xij. Assuming that all individuals have identical ma rginal utilities of in come and changes in utility associated with the new policy, then the marginal utility of income ( MUY i) and marginal social utility ( MSU i) will each equal one and the change in social welfare (due to the new policy) is equivalent to the cha nge in national income due to the policy. According to Cohn (2003) and Zerbe a nd Dively (1994), the marginal social utility and marginal utility of income are di fficult to estimate which causes many analysts

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16 to restrict their analyses to the efficiency aspect of the equation. This causes the equation that reflects the change in welfare to be reduced to: (2-11) W = pj xij. However, it must be kept in mind that if th e marginal utilities of income and marginal social utilities vary significantly among thos e influenced by the po licy, and the end goal is to maximize social welfare; the BCA coul d result in erred decisions. If the analyst feels that ignoring the marginal utilities of income and marginal social utilities is detrimental then he/she should avoid BCA that does so. Social Welfare Changes It should be noted that Arrow’s Impossibi lity Theorem (originally developed from research on election procedures) casts some doubt as to whether a social welfare (choice) function can be derived from an aggregation of individual preferen ces to allow for the optimal allocation of resources (Arrow 1963). This is due to the fact that the following conditions must be met before a “fair” social welfare function can be derived: Unrestricted domain or univ ersality. The social welfar e function must include each individual’s preferences. Non-imposition or citizen sovereignty. All societal preferences should be achievable through some set of individual preferences. There must be at least as many individua ls as there are op tions being debated. Non-dictatorship. The social welfare function should not be sensitive to only one individual. The function is responsive to more than one individual’s requirements. Monotonicity or positive association of soci al and individual values. The social welfare function should promote the change or not change at all if an individual modifies their preference order. An individual should never be penalized for modifying their preference. Independence of irrelevant al ternatives. If the social choice function focuses on a specific subset of alternatives, then the resulting outcome will be compatible with those specific alternatives. If individu als change their ranking of “irrelevant”

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17 alternatives it will have no impact on the social ranking of the “relevant” alternatives. This implies a limitation on the sensitivity of the social function. Benefit-Cost Analysis in Practice Benefit Cost Analysis has been used for analyzing a broad spectrum of projects. Stober and Falk (1967) offer a discussi on on using BCA for proposed local water allocation programs to help determine how a community should allot water among the various needs within a community. Faced w ith two alternative s cenarios, the authors offer analysis on a reimbursable community proj ect that can supply wa ter at a lower cost than that at which industrial and municipa l users can meet their own needs. By formulating a benefit-cost ra tio (BCR), they can determine if the community project is justified. They finally determine that the structure of corporate income taxes and the community’s lower costs of capital provide a large bias in favor of the community supplied water project. Benefit Cost Analysis has been used to evaluate the economic feasibility of treatment/eradication programs for other invasi ve species in Florida. In 2004, Zansler conducted a BCA of the Citrus Canker Er adication Program (CCEP). This study investigated the effects that citrus canker would have on th e citrus industry if it were allowed to become endemic, to demonstrate the benefits of the CCE P. Estimates of the costs were determined by the change in the cost of production and government expenditures on eradication of citrus groves in Florida. This form of analysis has been used to estimate the gains and losses from policies aimed at providing increased product safety for consumers. Dardis, Aaronson, and Lin (1978) used BCA to evaluate flammability st andards of children’s sleepwear as well as investigating the role BCA plays in determini ng whether product safety regulations are in

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18 the public interest. The research first delinea ted the general costs and benefits associated with implementing this safety regulation. The n, actual monetary values were assigned to the related benefits and costs of the safe ty regulation. Upon completing their BCA, the researchers determined that the new safety standard was cost effective in spite of a decrease in consumer choice. Haveman (1976) provides a summary of two cases using benefit cost analysis on human resource programs. The first case looked at the benefits and costs associated with the Upward Bound program. This government program was designed to recognize “high potential, disadvantaged youths” at the high school level, who would probably not be attending college, and provide them with specialized colleg e preparatory education to help lessen the education gap for less privileg ed students. The research evaluated the benefits and costs of the program from the pe rspective of the pupils enrolled in it, as well as the benefits and costs of the program as viewed from the rest of society. The study determined that the students viewed this progr am as a worthwhile activity; therefore, they believed the benefits outweighed the costs (u sing five and 10 percent discount rates). The additional analysis indicated that the pr ogram’s benefits outweighed its costs for the society at large, as long as the discou nt rate used is below seven percent. The second case study addresses the benefits and costs associat ed with a federal government program “designed to provide instit utional training in o ccupational skills to adult workers.” The cost-ben efit analysis sought to dete rmine if the program was a valuable social investment. The study showed that increases in the participant’s income could be attributed to the program. Add itionally, social benefits and costs of the programs were compared to reveal that the length of the program affected the ratio of

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19 benefits to costs. The shorter courses ha d higher benefit-cost ratios than the longer courses, where the present value of the costs exceeded the present value of the benefits. Gittinger (1982) offeed analysis on various agricultural projects, and specifically carried out a BCA on the Philippine Ilocos Irrigation Systems Improvement Project by formulating a BCR for the project. Blum, Damsgaard, and Sullivan (1980) provi ded a general discussion of the use of BCA in health care as it relates to three following areas: The use of BCA for analysis of diseasespecific programs of intervention from a prospective point of view (for illnesses such as polio, syphilis, and renal disease). This has historically con centrated on the economic impact of such diseases measured by the untimely loss of life or capac ity to function due to the illnesses. BCA has been used as a technique for the evaluation of alternative means of delivering medical services. Hospitals have used BCA to assist in determining if it would be cost effective to construct new ambulatory care centers or if the funds should be used for improving ex isting emergent care facilities. BCA has been implemented to estimate the return on public investments in areas such as medical research and health manpower development. Use of Mail Surveys Surveys have proven to be a useful tool in many areas of study for gaining insight into people’s opinions and beliefs, or obtai ning general quantitative information. More surveys are conducted by mail than through any other means (Dillman 1991). The U.S. Office of Management and Budget’s 1984 rese arch reported that 90 percent of the government’s surveys categorized as “sel f-administered” were conducted through mail procedures. The use of mail administered surveys has distinct advantages and disadvantages (Dillman 1991, Benson 1946, and Kramer and Schaffer 1954). One of the greatest advantages that has helped mail surveys gain popularity is the relatively low cost of implementing mail su rveys when compared with interviews

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20 conducted in person or by telephone. The re lative simplicity of administering mail surveys allows organizations and individua ls to conduct the surveys themselves as opposed to hiring outside agencies. Mail su rveys also make it possible to contact individuals when they are scattered acro ss a broad geographic region. Additionally, by accessing the necessary lists of potential respondents, mail surveys can be efficient at reaching specific subsets of the population such as college graduates, homeowners, or agricultural land owners. When mail surveys are used, the interviewer bias observed in phone surveys or personal interviews is elim inated. When anonymity is assured by the entity conducting the survey, the respondent is likely to be more forthcoming in mail questionnaires as opposed to personal interviews Finally, when the necessity arises to gather responses from all household members, mail surveys allow those members to be reached relatively easily as opposed to sche duling additional interviews if all the necessary members are not availa ble at one particular time. One of the disadvantages of using mail su rveys is that it is impossible to tell whether the respondent answered on their own or solicited answers from outside sources. If it is imperative that the re spondent give only their persona l opinion or answer questions based on their current level of knowledge, then mail surveys cannot assure this. The goal of gaining a representative sa mple of the population can be problematic, because those of higher education and/or income levels may be more likely to reply than those of a lower socio-economic class. Another difficulty is that the responses gathered by mail surveys can be biased towards those who are inclined to one or extreme or the other. In other words those with more polarized biases ar e more likely to respond than those who are uninformed or have more moderate positions on the subject.

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21 Due to the threat of respondent fatigue, ma il surveys must be kept relatively brief to avoid non-responses attribut ed to a lengthy questionnaire do cument. Furthermore, the importance of question sequence is lost on mail surveys due to the fact that nothing really prevents the respondent from perusing the w hole questionnaire befo re actually answering the questions. Finally, only a limited amount of demographic information can be gleaned from mail surveys. Respondents often feel that th is line of questioning is too invasive, especially when copious amounts of personal information are requested. It is imperative for a researcher to co nsider the pros and cons of the various methods used to gather survey information. No one survey method can be endorsed as better than another; the decision must be ma de on a case by case basis. According to Kramer and Schaffer (1954) when consideri ng the disadvantages of a technique the researcher must ask if: They are factors that would significantly influence the results of the survey? Does the disadvantage limit the scope of the technique or does it eliminate the technique for their part icular area of inquiry? Does the disadvantage apply to all survey techniques or just the particular one being considered? Are there any techniques to mitigate the disadvantageous effects? The Contingent Valuation Method (CVM) It is especially difficult to measure or put a monetary value on irreplaceable goods like health or the environment. Often the mark et fails to establish prices for public goods because they are nonexclusive. This is why there is the need to find out what values people place on these public goods. Hanema nn (1994) points out that a survey or questionnaire offers a way to demonstrat e public demand for a good, especially when indirect methods fail to offer a complete m easure of a personÂ’s value for a particular

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22 good. While price systems are one way to determine how people establish what something is worth; another way is to simply ask them through surveys or votes (Schelling 1968). Mitchell and Carson (1989) submit that in general, the Contingent Valuation Method (CVM) appears as accurate as other me thods, and is capable of measuring types of benefits that other methods can measure only with difficulty, if at all. The fact that economists now have a tool to value goods, previously thought almost impossible to value, has helped this valuation method gain worldwide popularity (Navrud 1992). The CVM uses survey questions to determine an individualÂ’s preferences for public goods by establishing what they would be willing to pay for specific improvements in them; thus eliciting their willingness-t o-pay (WTP) or willingness-to -accept (WTA) some loss in dollar amounts (Mitchell and Carson 1989). If the study has been car efully designed and pre-tested, the responses gathered should sy mbolize valid WTP responses (Mitchell and Carson 1989). If the random sample gathered has a sufficiently high response rate and appropriate measures are taken to adjust for non-respondents and poor quality responses, the results can be generalized (with a known margin of error) to represent the population from which the sample was taken (Mitchell and Carson 1989). The Carson et al. (1994) bibliography lists more than 1600 studies and papers from more than 40 countries that used CV on varied topics such as transporta tion, sanitation, health, th e arts and education, and the environment. While there is no one standard for the design of contingent valuation surveys, it is important for them to include several key el ements, because the quality of responses is directly related to the qualit y of the design of the survey. To begin, the survey must

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23 contain a clear descrip tion of the policy/program that th e respondent is valuing (Portney 1994). If a clear description is lacking, the respondent will likely be less able to accurately value the situation in question. Th e survey must include a means for eliciting a value or a choice from the respondent, th rough the use of tools such as referendum formats, open-ended questions, or bidding game s (Portney 1994). Finally, CV surveys usually seek to gather the demographic in formation of the respondents along with their attitudes toward the environm ent or a description of thei r recreational behavior for environmental and/or natural res ource studies (Portney 1994). While the CVM is widely used around the world, the subject is not without debate or its detractors. In 1992 a panel of expert s, including Nobel laureates, was convened to advise the National Oceanic and Atmospheri c Agency (NOAA) if the “CVM was capable of providing estimates of lost nonuse or exis tence values that were reliable enough to be used in natural resource damage assessmen t” (Portney 1994, p.8). While the “bottom line” of the panel report found that “CV studi es can produce estimates reliable enough to be the starting point of a judicial process of damage assessment, including lost existence values,” they also developed a strict a nd lengthy framework under which CV studies should be conducted if they were to produce reliable estimates (Portney 1994, p. 8). Among those guidelines, the panel stated that face-to-face interviews are preferred to telephone surveys and telephone surveys are pr eferred to mail questionnaires, and that studies should gather information on willingn ess to pay to prevent future incidents instead of determining minimum compensati on required for an event that has already occurred. Additionally, studies using CV should implement the referendum format, where respondents are asked how they would vote for a particular program that would

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24 achieve some level of environmental benefit in exchange for higher taxes or commodity prices. The panel offered that the reasoning behind this guide line is that these types of decisions more accurately reflect the reality of real world decisions and would provide a more accurate valuation than the typical open-ended question that seeks a maximum willingness-to-pay value. The panel also st ated that analyses using the CVM should open with a scenario to accurately illustrate th e anticipated effect of the program being considered as well as a reminder that a willingness-to-pay amount for the proposed policy/program would reduce their disposab le income. Finally, follow-up questions should be provided to ensure that the indivi dual could comprehend the choice they were being asked to make and to discover the reasoning behind their response. Some economists critical of the CVM have charged that it is not useful because, in their view, the resulting information is cont rary to economic theory (Hanemann 1994). To that end, critics have sugge sted that the CVM is insens itive to scope, thereby making it an unreliable method for obtaining useful information regarding natural resource damage estimates. Kahneman and Knetsch (1 992) put forth that their study of WTP for the clean-up of lakes in Ontario, Canada show s that respondents’ WTP to clean up all of the lakes in Ontario is less than the WTP for the clean up of lakes in a specific region. Logic would suggest that an individual’s WT P for cleaning up a larg er number of lakes would be higher than their WT P for cleaning up a smaller area of lakes. It has been argued that this insensitivity to scope is unavoidable because “respondents are expressing ideological values, receiving a warm gl ow, or purchasing moral satisfaction” (Kahnemann and Knetsch 1992, p. 64). The NOAA panel also included a requirement that studies using the CVM should test for the sensitivity of responses to the scope of the

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25 damage described in the scenario. To addr ess this issue the panel suggested that the questionnaires should seek to determine whet her or not the responde nts were willing to pay more to prevent more serious ecological accidents. Previous Research on the Economic Impacts of Melaleuca While the biological research on Melaleuca is now quite extensive, there is a noticeable paucity in the amount of economic research that has b een conducted on this invasive species. However, there are a few researchers who sought to analyze the economic impacts that Melaleuca has had in Florida relativel y early in the eradication programÂ’s life. Balciunas and Center (1991) discussed the prospects and dilemmas that could arise if biologi cal control is used in the fight against Melaleuca Additionally, they conducted a Benefit Cost Analys is under the assumption that Melaleuca is allowed to spread unchecked. Their research helped to provide a good starting point for the benefits and costs to be enumerated. For the purpose of this research, howev er, the Balciunas and Center research is used as a guide to show the worst ca se scenario for the negative impacts of Melaleuca Diamond, Davis, and Schmitz (1991) also provided additional research on the economics of the Melaleuca invasion. They specifically considered the economic impact associated with the addition of Melaleuca to the Florida Prohibited Aquatic Plant List and provided a more extensive Benefit Co st Analysis of the spread of Melaleuca The authors went into great detail considering possible effects of Melaleuca on FloridaÂ’s ecotourism, sport fishing and game hunting, as we ll as its effects on Fl orida agriculture and the ecosystem in general. They also speci fically provided useful cost figures for the economic damages caused by wildfires fueled with Melaleuca Their research helps to provide a checklist of sorts to ensure a thor ough analysis. However, due to the fact that

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26 both of the previously mentioned articles we re written during the early stages of the Melaleuca eradication/treatment initiative, and the changes that have taken place since then, they will have a rather limited application in this research.

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27 CHAPTER 3 SURVEY DESIGN, CONTENT, AND ADMINISTRATION Survey Methods As discussed in the previous chapter, this research used mail surveys to gather part of the information necessary to this project. The quality of a surveyÂ’s design is arguably the deciding factor as to whether it will yield useful and reliable data. Over time, research has been undertaken to try to devise a recipe, of sorts, that survey designers can follow to help increase the likelihood that thei r surveys will yield their greatest potential. This research uses DillmanÂ’s (1978) Total Design Method (TDM) as a guide for survey design. Survey Study Area, Target Populations, and Sampling The study area for these survey s included the 10 southernmost counties in Florida: Broward, Charlotte, Collier, Glades, Hendr y, Lee, Martin, Miami-Dade, Monroe, and Palm Beach. Just over 2.5 million househol ds are located in these counties (BEBR, 2004). For the residential survey, a randomly se lected sample of 5,001 households, which represented 0.2 percent of th e population, was purchased from a market research firm (MSG, Inc.). Due to the fact that many Hisp anic non-English speaking individuals reside in South Florida, a Spanish language version of the survey mirrored each page of the English version. Both agricultural owners/ operators and managers of public parks/preserves were targeted for the survey of professional la nd managers. Agricultural land owners were

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28 selected from a list compiled from county pr operty appraisers by the Florida Department of Revenue in Tallahassee. A random sample of 2,000 landowners with property classified for agricultural use was selected for the survey. This sample represented 17 percent of the population of about 11,500 landowners. For public lands, a list of 285 names wa s obtained from the United States Department of Agriculture-Agricultural Re search Service (USDA-ARS) representing managers of parks and preserves for local, state, and federal government agencies, and managers of rights-of-ways for public utilities. Surveys were mailed to all managers on this list. Survey Content Beginning in fall 2003, two separate que stionnaires were developed for the respective survey groups of re sidents and professional land managers. The content of these questionnaires was developed in c onsultation with The Areawide Management Evaluation of Melaleuca (TAME Melaleuca ) project collaborators at the University of Florida Institute of Food a nd Agricultural Sciences (UF-IFAS), USDA-ARS, and the South Florida Water Management District ( SFWMD). The questionnaires and informed consent protocol for the survey were review ed and approved by the Un iversity of Florida Institutional Review Board (UF-IRB) for co mpliance with ethical standards for human subject research. Following the suggestions in DillmanÂ’s (1978) TDM, each survey had an arrangement of various colored photographs on the front cover. Inside the front cover included an introductory statement explai ning who was conducting the study, the purpose of the questionnaire, the importance of provi ding a response, general instructions for completing and returning the questionnaire, the anticipated length of time for completion of the survey, a guarantee of confidentiality, contact information should the participant

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29 have any questions, and a statement of gra titude for participating in the study. The residential survey was seven pages in lengt h for each language, yielding 14 total pages, inclusive of the opening instru ctions and areas provided for comments. The professional land manager survey was a total of nine page s. Each survey conc luded by thanking the respondents for their participa tion and asking that they retu rn the questionnaire in the postage-paid envelope provided. Copies of the survey materials are provided in the Appendix. Residential Survey The residential survey was designed to he lp provide some insight into attitudes, opinions, and experiences with Melaleuca by the general public. The survey questionnaire focused on determining the exte nt of residentsÂ’ know ledge and experience with both invasive plants and Melaleuca specifically. The content of the survey can be broken down into three categories: (1) an in troductory assessment of experience with and knowledge of Melaleuca (2) an assessment of opini ons and willingness-to-pay information, and (3) demographic information. An introductory line of questions were posed to determine the respondentÂ’s level of aw areness of invasive plants in the state. Residents were asked to indi cate if they could recognize Melaleuca and if they were aware of its non-native status. Then, res pondents were asked to indicate how much, if any, Melaleuca was located on their property. The next questions in the survey sought to determine what control methods residents were currently using or interested in learning more about, along with any fact ors that limited th eir ability to cont rol the plant. Residents were also asked to indicate from which sources they received information about Melaleuca The first section ends by asking th e respondent to estimate what range of money they had spent (since 1990 or owning their property) specifi cally for the control

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30 of Melaleuca on their property. If the amount wa s over $500 the respondents were asked to write in the estimate. The second section began by asking responde nts to indicate whether they felt that Melaleuca had negatively affected their property value. If the respondent answered “yes”, they were asked to then indicate by wh at percentage it had negatively affected the value. Residents were also asked to indica te how much they would be willing to pay to remove/eradicate Melaleuca on their property. If they we re willing to pay more than $500 they were asked to write in a specific amount. Respondents were then given a list of outdoor activities and asked to indicate how many days they engage in those activities on an annual basis. The responde nt was provided with space to write-in an activity that was not listed. Residents were asked if Melaleuca had in any way affected their enjoyment of the outdoors. If the respondent answered yes, they were then asked to specify if they had been negatively or posit ively affected. The second section concluded by asking respondents to indicate how much th ey would be willing to pay, per visit, to reduce Melaleuca in the areas where they engage in outdoor recreational ac tivities. If the amount was more than $25 per visit, they we re asked to write-in a specific amount. The third and final section of the reside ntial survey sought to gather demographic information about the respondent. Informati on was gathered on the zip code in which they resided, the duration of residence at th eir current location, and the ownership status of their residence. Questions such as gende r, year of birth, educational achievement, ownership of 25 or more acres of land in Fl orida, participation in state/local elections, household size, and pre-tax income (for 2003) we re also asked. Space was also provided

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31 for the respondents to add any comments they had as well as to indicate their name and address if they wished to receiv e a summary of the survey results. Professional Land Manager Survey While there are some similar questions in the two surveys, the survey administered to the professional land managers was intende d to gather more technical information on the level of infestation and pract ices used for the control of Melaleuca Both professional agricultural land managers a nd park/preserve managers received the same survey questionnaire. The content of the manage rÂ’s surveys can be broken down into two categories: (1) general descriptive informa tion reflecting the management unit, and (2) specific information on Melaleuca control. In the first segment, managers were asked to indicate their name followed by their or ganizationÂ’s name, address, and telephone number. They were then asked to specify in which counties their land holdings or management units were located. In order to determine the ownership classification of their land, managers were asked to indicate how much of their land was privately owned, publicly owned, or privately leas ed. To gather more specif ic information on the landÂ’s use, managers were asked to indicate how ma ny acres of their land fell within certain categories, such as cropland, co mmercial timberland, park/prese rve, etc. In the hopes of gaining some insight into the factors aff ecting land management decisions, respondents were asked to indicate whether various f actors exerted significant, moderate, or no influence over their management choices. Th e managers were then asked to report how many acres of exotic plants currently occupied their management area as well as indicate how many acres of each plant had been treated from 1990-2003. The section of the survey specificall y designated to acquire information on Melaleuca began by asking managers to indicate wh at control methods they had used on

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32 Melaleuca They were then asked to specify th e area treated for each control used during 2003 and from 1990-2003. Managers were also as ked to indicate if they had not used any control measures for Melaleuca Respondents were asked to indicate whether they planned to continue using or to adopt specific control measures for Melaleuca and indicate if they would like to receive more information on an y of the control types listed, as well as indicate the type s of sources that provided Melaleuca control information to them. Managers were asked to indicate any reasons that limited their ability to control Melaleuca on their property. Additionally, th e managers were asked to rate the usefulness of the information in terms of “useful”, “somewhat useful”, or “not useful”. Respondents were asked to indi cate the costs for control of Melaleuca on their management unit during 2003 as well as indi cate the total expenses for any special equipment or heavy machinery purchased specifically for the control of Melaleuca since 1990. The survey went on to ask respondent s to indicate if the total costs of Melaleuca control on their land had increase d, decreased, or stayed about the same over the past five years. Managers were also allowed to indica te that they “didn’t know” the trend. If the respondent indicated that the costs had increased or decreased they were asked to indicate by what percentage. Respondents were also asked to indicate if they felt that Melaleuca had reduced their land’s agricu ltural productivity, lowered its market value, impaired its ecological function, or diminished its recreationa l use. If the respondent indicated that it had negatively affected one of these aspects they were asked to pr ovide the percentage loss that Melaleuca had caused. Professional managers were also asked to indicate their organization’s gross income or annual budget for land management from 2003. Participants were given the option of writing in a specific amount, indicating a range, or

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33 indicating that they did not know the amount. Finally, manage rs were given the option of adding additional comments as we ll as indicating whether they would like a copy of the results through the mail or e-mail. Survey Administration Survey administration was begun in June 2004 following the protocol of the TDM (Dillman). An introductory letter was first ma iled to all targeted respondents to notify them that they had been selected for the su rvey, explaining the purpos e of the survey, and requesting their cooperation. Approximately one week later, questionnaires were mailed along with a postage-paid return envelope and a cover letter resta ting the purpose of the study. Reminder postcards were mailed one w eek later. A second complete mailing of the survey and reminder postcard wa s repeated six weeks later. After the completed surveys were receive d from respondents and categorized into the appropriate group (i.e.park/preserve managers, agricultural managers, and homeowners) a code number was assigned to each completed questionnaire. The survey responses were entered into an Excel worksheet and then verified for accuracy. If contact information was provided in the response, fo llow up phone calls or emails were used for verification or clarification as necessary.

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34 CHAPTER 4 SURVEY RESULTS Results for Professional Managers Land Ownership Status Land area owned and leased by professional managers responding to the survey is summarized in Table 4-1. A total of 5.4 milli on acres were reported, which consisted of about 5.1 million acres controlled by park managers and 317,000 acres controlled by agricultural mangers. The vast majority of land managed by park/preserve managers was publicly owned, although 86,372 acres were privately owned. In contrast, most of the land managed by agricultural managers was privately owned. Publicly owned landholdings managed as parks/preserves averaged 74,488 acres per manager, and ranged in size from four acres to 1,400,000 acres. Privately owned agricultural landholding averaged 775 acres per manager and ranged from less than 1 acre to 140,000 acres. A relatively small amount of land was being privately leased by both park and agricultural mana gers. When these numbers ar e expanded to represent the full population of agricultural managers in th e 10 county study area of South Florida, an estimated 1.74 million acres would fall unde r private ownership, 73,893 acres would be privately leased, and 8,884 acres wo uld be classified publicly owned. Land Use In terms of land use, some 6.94 mill ion acres were reported managed by park/preserve managers, and 319,771 acres were reported managed by agricultural managers, giving a total of 7.26 million acres (Table 4-2).

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35 Table 4-1. Land area managed by survey ed professional land managers in Florida. Classification Number Sum (Acres) Mean (Acres) Minimum (Acres) Maximum (Acres) Park/Preserve Managers 805,084,967 Privately Owned 1086,3728,637770,000 Publicly Owned 674,990,67074,48841,400,000 Privately Leased 37,92526421057,500 Agricultural Managers 431316,528 Privately Owned 390302,1327750.3140,000 Publicly Owned 31,54551551,380 Privately Leased 3812,85133812,700 Overall Total 5115,401,49510,57011,400,000 The largest type of land-use by area as reported by survey respondents was for parks/preserves, comprising a total of 4.80 million acres, or 73,883 acres per manager. The next largest land uses reported by park managers were right-of-ways totaling 871,483 acres, followed by lakeshore (508,272 acres), mitigation areas or constructed wetlands (373,017 acres). Miscellaneous other uses totaling 356,262 acres included target ranges, recreational areas, and office buildings Some park/preserve managers indicated that some of their land was used for pa sture/range land, crop pr oduction, fruit/citrus groves, and nurseries, but none indicated that their land was being used as forest for commercial timber production. The most commonly reported land use by agricultural land managers was pasture/rangeland, with 38 percent of respondents reporting a total of 143,243 acres, averaging 853 acres per respondent. Crop la nd was the next larges t land use reported totaling 116,388 acres, followed by fruit/citrus groves (34,275 acres), and right-of-ways (4,547 acres). Miscellaneous other uses totaling 18,272 acres reported by agricultural managers included residences, ponds, horse fa rms, and barns. When these numbers are

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36 expanded to represent the populat ion of agricultural managers in South Florida, it is estimated that a total of 1.83 million acres were being managed, including 823,647 acres for pasture/rangeland, 669,231 acres for crop la nd, 197,081 acres for fruit/citrus groves, and 26,145 acres for right-of-ways, and 105,064 acres for miscellaneous other uses. Table 4-2. Land use types and areas managed by professional land managers in Florida. Park Managers Agricultural Managers All Managers Land Use Type # Sum (Ac) Mean (Ac) # Sum (Ac) Mean (Ac) Sum (Ac) Park/Preserve 65 4,802,38973,883 8304 4,802,419 Right of Way 16 871,48354,468364,547126 876,030 Lakeshore 6 508,27284,7127193 508,291 Mitigation/Wetland 14 373,01726,644925128 373,268 Pasture/Range 4 25,2106,303168143,243853 168,453 Crop 2 90045050116,3882,328 117,288 Fruit/Citrus 3 1,9086369834,275350 36,183 Nursery 5 1941031,39514 1,414 Forest 0 101,351135 1,351 Other Use(s) 16 356,26222,2668318,272220 374,534 Total of all uses 6,939,460319,771 7,259,231 Factors Affecting Land Management Survey respondents were asked to rate va rious factors that influenced their land management decisions as either “significant” “moderate”, or “none” (Table 4-3). These factors included agency funding, adverse weathe r conditions, availabil ity of agricultural land, encroachment of urban land uses, forei gn or other state comp etition, cost of inputs or supplies, prices for crops, fr uit, or livestock invasive plants, predators, insect pests, and the ability to conduct prescribed burns. Th e average ratings for each of these factors are summarized in Figure 4-1, where each respondent’s rating was assigned a number value: 0 for “none”, 1 for “moderate”, and 2 for “significant”.

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37 For park/preserve managers, agency funding was the most influential factor in land management decisions; being rated as signifi cant by 77% and moderate by 19%. Perhaps this is not surprising since many of these res pondents work for local, state, or federal agencies. Invasive plants were rated as a si gnificant factor by 73% of park managers, while 25% rated them as a moderate influen ce. The ability to c onduct prescribed burns was rated as significant by 39% of park/preserve managers, and as moderate by 23%. Input costs were considered significant by 36% and modera te by 53% of park/preserve mangers. Urban encroachment was rated as a significant or moderate influence by 28% and 40% of these respondents, respectively. Adverse weather was viewed as a moderate influence (71%), although this may be considered more im portant after the 2004 hurricane season. Only 8% indicated that pr edators or insect pest s were a significant factor in their management, while 42% rate d these pests as moderate, and 50% gave considered it of no significance. Factors other than those listed in th e survey (such as the general public, staffing, and wildfires) were ra ted as significant by 38% of park/preserve managers. Factors that were considered to have little or no affect on the park/preserve management decisions were prices (99%), av ailability of agricultural land (93%), and competition (86%). For agricultural managers factors influencing land ma nagement were rated lower overall. Prices for crops, fruit and livestoc k was the most important factor, with 29% indicating it was significant a nd 33% as moderate. The costs for inputs or supplies were rated as a significant factor by 24% of agricultural managers and as moderate by 41%. Adverse weather conditions were a significan t factor for 23%, urban encroachment was rated as significant by 23%, a nd availability of agricultura l land was significant for 20%.

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38 The latter finding may be due to the fact that most agricultural managers already own/lease their land, so they arenÂ’t worried about acquiring any additional land, or it may indicate that agricultural ma nagers generally do not intend to expand their operations. Some 19% of agricultural managers rated predators and insect pests as a significant factor, with 46% rating them as moderate. I nvasive plants were ra ted as significant by 16% and as a moderate influence by 43%. Foreign or other state competition was generally not viewed as important, which is somewhat surprising given the significance of commodity prices. Table 4-3. Factors influenci ng management decisions by professional land managers in Florida. Park Managers Agricultural Managers Factor None % Moderate % Significant % None % Moderate % Significant % Agency funding 41977917 2 Adverse weather 1571154037 23 Availability of ag. land 93705130 20 Urban encroachment 3340275027 23 Competition 861317315 12 Costs 1253363541 24 Prices 99103933 29 Invasive plants 325734143 16 Predators/ Pests 504283646 19 Prescribed burns 3823396626 8 Other factors 441938893 8

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39 Figure 4-1. Average weighting of factors in fluencing management by professional land managers. Area Occupied By Invasive Plants and Area Treated The importance of Melaleuca as an invasive plant was a ssessed in relation to other invasive plants, based on the area currently occupied in 2003, and the area treated during the period 1990 to 2003. The area occupied wa s intended to represent the areas of contiguous stands, not very small isolated pa tches and individual out lying trees. The ratio of area treated since 1990 to the area occupied currently was also ta ken as a gauge of the intensity of treatment by land managers. For park/preserve managers, Melaleuca was the invasive pl ant reported to occupy the largest area ( 619,317 acres) in 2003. Melaleuca also had the largest area treated during 1990-2003 (402,088 acres), wh ich represents 65% of the area currently occupied. 1.7 1.0 0.1 0.2 1.2 0.0 1.7 0.6 1.0 0.1 0.8 0.7 0.7 0.4 0.9 0.9 0.7 0.8 0.4 0.2 0.9 1.9 00.511.52 Agency Funding Adverse Weather Availability of Ag. Land Urban Encroachment Competition Costs Prices Invasive Plants Predators/ Pests Ability to conduct prescribed burns Other Factors affecting mgmt.Average Significance Agricultural Managers Park Managers

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40 Brazilian Pepper was the second most co mmon invasive plant, occupying 425,805 acres in 2003, with 75,215 acres treated between 1990 and 2003. This represented 18% of the area occupied in 2003. Among other sp ecies, Old World Climbing fern ( Lygodium ) occupied 113,884 acres, and 49,213 acres were treated (43% of area occupied). Australian Pine ( Casuarina ) occupied 111,782 acres, with 16,598 acres treated (15%), Cogon grass ( Imperata ) occupied 20,147 acres, with 6,527 acres treated (32%), Tropical Soda Apple ( Solanum ) occupied 15,418 acres, with 3,475 acres treated (23%), and miscellaneous other plants occupied 11,433 acr es, with 7,094 acres treated (62%). Some of the other plants frequen tly listed were air potato ( Dioscorea bulbifera ), downy rose myrtle ( Rhodomytrus tomentosa ), latherleaf ( Colubrina asiatica ), carrot wood ( Cupaniopsis anacardioicles ), and cattail ( Typha ). For agricultural managers, 94 managers reported a total area of 2,134 acres occupied by Melaleuca in 2003, and 57 managers reporte d treating a total of 1,460 acres during 1990-2003. This represente d 68 percent of area occupi ed. This suggests that agricultural managers have treated Melaleuca at similar rates as park managers have, however other indicators in this survey and ot her research imply that park managers have acted much more aggressively. Tropical Soda Apple ( Solanum ) was reported by agricultural managers to o ccur on 10,393 acres in 2003, and 7,855 acres (or 76% of this area) were treated. Brazilian Pepper ( Schinus ) occupied 7,096 acres and 2,768 acres (39%) were treated. Miscellane ous other invasive plants, including air potato, dog fennel, and smut grass, occupied 2,561 acres, and 2,094 acr es (82%) of those plants were treated. When these numbers are expanded to repr esent the tota l population of agricultural managers, Melaleuca is estimated to cover 12,271 acr es in South Florida during 2003,

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41 and 8,395 acres were treated between 1990 and 2003. The area infested by other invasive plants on agricultural lands is estimated at 139,058 acr es, including 59,760 acres for Tropical Soda Apple, and 40,802 acres for Brazilian Pepper ( Schinus ). Table 4-4. Land area infested w ith and treated for invasive species by professional managers in Florida Park/Preserve Managers Agricultural Managers Area Currently Occupied Area Treated Since 1990 Area Currently Occupied Area Treated Since 1990 Species # Acres # Acres # Acres # Acres Paper bark or Punk tree ( Melaleuca ) 59619,31754402,08894 2,134 571,460 Australian Pine (C asuarina ) 55111,7825016,59829 34 155 Brazilian Pepper ( Schinus ) 68425,8056575,215146 7,096 1042,768 Cogon grass ( Imperata ) 3320,147316,52714 320 973 Old World Climbing fern ( Lygodium ) 45113,8844049,21323 178 1624 Torpedo grass ( Panicum ) 3325,0603111,00840 1,468 31888 Tropical Soda Apple ( Solanum ) 3215,418253,47537 10,393 327,855 Other plants 3711,433367,09433 2,561 182,094 Total 3621,342,846332571,218416 24,184 28215,167 Methods Used for Treating Melaleuca Managers were asked indicate if they had used a specific method for controlling Melaleuca and then to indicate the area they treated with th at method in 2003 and also cumulatively from 1990 to 2003. Respondents we re given a choice of several options: Mechanical removal (felling, mowi ng, tilling, grubbing, disking, etc.) Foliar or soil applied herbicides Basal frill followed by herbicide treatm ent (also known as “hack and squirt”) Girdling followed by herbicide treatment (a ri ng of bark is removed from the base of the tree and then treat ed with an herbicide)

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42 Felling followed by herbicide treatment on the cut stump (“stump treatment”) Biological control with benefi cial insects (natural enemies of the tree are released which may cause stress in establishe d trees and death of younger saplings) Biological controls combined with one or more other methods. Since respondents were given the opportuni ty of indicating more than one control method, a count was taken to see how many mana gers chose at least one control choice, and this number was used to compute the percentage of managers responding in the affirmative for using a particular control method. Among park/preserve managers, 82% indi cated they had employed the stump treatment, 59% used hack and squirt, 51% used mechanical control methods, 28% employed biological control, 21% used biolog ical control combined with one or more other form(s) of control, and 7% reported using some other method of control such as fire. Many agricultural managers did not have Melaleuca on their property, and if they did, many chose not treat it. So, it was not surp rising that 71% of agricultural managers had not used any particular control measures for Melaleuca Among agricultural managers who did use controls, 33% indica ted they had employed mechanical methods for control, 10% used foliar or soil app lied herbicides, 8% reported using stump treatment, and 4% used hack and squirt (Table 4-5).

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43 Table 4-5. Methods used for treatment of Melaleuca by professional land managers in Florida. Park Managers Agricultural Managers Method Used Number Percent Number Percent Mechanical 315170 33 Foliar/Soil herbicides 223620 10 Hack and Squirt 36598 4 Felling and herbicide (stump treatment) 508216 8 Biological Control 17283 1 Biological control + other method 13210 0 Other methods 374 2 No Controls 1321149 71 The area of Melaleuca treated using various control methods in 2003 and cumulatively during the period 1990-2003 is su mmarized in Table 4-6. The total area treated in 2003 was 86,731 acres, and the to tal area treated since 1990 was 422,449 acres. For park/preserve managers, the total area treated in 2003 was 84,740 acres, and the area treated since 1990 was 419,741 acres. The stump tr eatment (felling + herbicide) was used over the largest area (303 ,933 acres) since 1990, followed by hack and squirt (52,476 acres), foliar or soil applied herbicides (36,622 acres), mechanical methods (16,625 acres), and biological control (12,642 acres). Biological controls combined with one or more other method(s) were used on 80,575 acr es, and together with the area treated strictly by biological control represented 93,217 acres. For ar ea treated in 2003, the most important method used was stump treatme nt (46,958 acres), followed by foliar/soil herbicides (15,987 acres), and hack and squi rt (11,494 acres). In comparing the area treated in 2003 with the averag e annual rates since 1990, it is apparent that the use of all treatment methods has accelerated in 2003 for parks/preserves. For agricultural mana gers, overall area of Melaleuca treated by any particular method since 1990 was significantly less than th e park/preserve mana gers, at about 2,707

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44 acres, including mechanical methods (1,957 acres), stump treatment (274 acres), and foliar/soil-applied herbicides (355 acres). Th e smaller area treated for 1990-2003 than for 2003 in some cases was apparently due to reporting errors. Table 4-6. Number of profe ssional managers using various control methods and area of Melaleuca treated in Florida, 2003 and 1990-2003. Park Managers Agricultural Managers Area Treated 2003 Area Treated 1990-2003 Area Treated 2003 Area Treated 1990-2003 Method Used # Acres # Acres # Acres # Acres Total Area Treated 1990-2003 (Acres) Mechanical 20 4,5922214,669431,36737 1,95716,625 Foliar/Soil Herbicides 15 15,8021536,267151858 35536,622 Hack and Squirt 23 11,4542852,4377405 3952,476 Felling + Herbicide (stump) 37 46,56237303,6591439610 274303,933 Biological Control 7 6,3101012,600232 4212,642 Biological + Other 4 4,242680,5750 00 080,575 Other Control 3 2031100 01 40150 Total* 109 84,740121419,742811,99163 2,707422,449 Total area excludes biologica l plus other control methods, to avoid double counting. Managers were also asked to indicate wh ether they planned to use or continue using various control met hods (Table 4-7). Among park/preserve managers who answered this question, the la rgest share intended to use st ump treatment (85%), followed by hack and squirt (72%), mechanical contro l (50%), and biological control (45%), or biological control combined w ith other methods (40%). Fo r agricultural land managers, the majority intended to use mechanical met hods (79%), with much fewer intending to use foliar/soil applied herbicides (29%), st ump treatment (27%) or “hack and squirt” (16%). Very few agricultural managers e xpressed interest in biological control.

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45 Table 4-7. Intentions fo r future use of various Melaleuca control methods by professional managers in Florida. Park Managers Agricultural Managers Method Number Percent Number Percent Mechanical 30505870 Foliar/Soil herbicides 23382429 Hack and Squirt 43721316 Felling + Herbicide 51852227 Biological Control 274545 Biological + Other 244034 Other Methods 3567 Managers were also asked whether they were interested in receiving additional information about any of the specific Melaleuca control methods (Table 4-8). Most park/preserve managers were interested in l earning more about biolog ical control (74%), but a majority was also interested in folia r/soil applied herbicides and stump treatment (65%), hack and squirt (58%), and mech anical methods (52%). Among agricultural managers who responded to this question, 40% to 50% wished to learn more about biological control, stump treatment, soil/folia r herbicides and hack and squirt. The low interest in learning more about mechanical c ontrol, at the same time this group expects to continue using this method extensively, s uggests that this method is well understood. Table 4-8. Requests for more information on Melaleuca control methods by professional managers in Florida. Park Managers Agricultural Managers Method Number Percent Number Percent Mechanical 165212 25 Foliar/Soil herbicides 206522 45 Hack and Squirt 185822 45 Felling + Herbicide 206524 49 Biological Control 237424 49 Biological + Other 165217 35 Other Methods 5163 6

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46 Barriers to Controlling Melaleuca Land managers were asked to choose from a list of factors that may have limited their ability to control Melaleuca (Table 4-9). Among park/preserve managers, the biggest barriers identified were inaccessibili ty to infestations (22%), expense (18%), excessive size of infestations (15%), lack of cost sharing programs (13%), and lack of time (12%). However, a significant proportion of these respondents (3 2%) indicated they encountered other types of ba rriers not specifically identif ied in the question. Some of these other barriers included: infestations ar e too small, lack of needed equipment or knowledge to use controls, fear of harming othe r beneficial plants, fe ar of or dislike for using chemicals, and environmental regula tions. Although they were listed in the question, some respondents wrote-in that lack of money and lack of time were barriers to implementing controls. Only 13% of park/preserve managers said that Melaleuca was not a problem for them. Agricultural land mangers responded quite differently to the barriers to control question. Seventy-four percent i ndicated that they did not have Melaleuca on their property and 31% reported that Melaleuca was not a problem for them even it they did have it. Some 9% of agricultural managers repo rted that their infestations were too small, 6% indicated that controls were too expensiv e, 5% indicated they lacked the necessary equipment to carry out control measures, a nd 5% indicated a barr ier other than those listed in the survey. No particular barrier was mentioned more than any other; however, some respondents stated that there we re no economic incentives for removing Melaleuca that licenses were needed for purchasing the necessary herbicides, and that some areas required permits for removing the trees. It is interesting to note that one respondent

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47 stated that Melaleuca trees provide shade in pastures, which suggests that there may be some benefits of Melaleuca for agricultural use. Table 4-9. Barriers to controlling Melaleuca by professional managers. Park Managers Agricultural Managers Barriers Number Percent* Number Percent* No Melaleuca on property 1728227 74 Not a problem 81396 31 Don't care 0013 4 Infestations too small 5828 9 Infestations too large 9158 3 Controls won't work 003 1 Don't know how to use controls 358 3 No time to use controls 7123 1 Afraid of harm 355 2 Afraid of/Dislike 3513 4 Infestation inaccessible 13226 2 Lack equipment 5816 5 Environmental regulations 234 1 No cost sharing 81312 4 Controls too expensive 111819 6 Other reason 193214 5 Percent of respondents an swering this question. Sources and Usefulness of Information for Melaleuca Control Professional land managers were asked if they had received information about Melaleuca from one or more of 13 possible so urces (Table 4-10). These respondents were also asked to classify the usefulness of these sources as either “useful”, “somewhat useful”, or “not useful” (Table 4-11). These classifications we re scored on a scale of 2, 1 or 0 respectively in order to compute a weighted average rating (Figure 4-2). Park/preserve managers who responded to this question indicated that state and federal agencies were their main source of in formation, with 83% indicating that they had received information from these sources, followed by UF/IFAS extension (72%), land managers’ advice (67%), pamphlets or bul letins (60%), land managers’ observations

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48 (58%), and professional organizations (52%). Other information sources or media that were received by less than 50 percent of respondents were weed professionals, area demonstration plots, TAME Melaleuca, video cassettes or CDs, internet websites, computer software, and email. In terms of the usefulness of information from state and federal agencies, 88% of park/preserve manage rs rated it as a useful source, 10% rated it as somewhat useful, and 2% indicated it wa s not useful (Table 4-11), representing an overall average score of 1.9 (Figure 4-2). Ot her information sources with high usefulness ratings were UF/IFAS extension (1.9), mana ger observations (1.8), land manager advice (1.8), weed professionals (1.8) professional organizations ( 1.7), internet websites (1.7), pamphlets/bulletins (1.6), a nd the TAME project (1.6). Table 4-10. Information sources and t ypes of media used by professional land managers in Florida. Park Managers Agricultural Managers Sources Number Percent Number Percent State and federal agencies 508331 44 Professional organizations 315216 23 Land manager observations 355812 17 UF/IFAS extension 437233 47 Weed professionals 254210 14 TAME Melaleuca 22375 7 Land manager advice 406713 19 Pamphlets or bulletins 366017 24 Video cassettes or CDs 9154 6 Area demonstration plots 12204 6 Computer software 354 6 Website/Internet 213514 20 E-mail/direct notification 15254 6 Other information source 589 13 Among agricultural managers who responded to this question, 47% indicated they had received information from UF/IFAS extension, followed by state and federal agencies (44%), pamphlets/bul letins (24%) and professional organizations (23%) (Table 4-10). In terms of usefulness, the top ra ted sources were UF/IFAS extension (1.4),

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49 manager observations (1.1), state/federal agen cies (1.1), weed professionals (1.1), land manager advice (1.1), and inte rnet websites (1.1) (Figure 42). None of the agricultural managers indicated they considered area dem onstration plots, computer software/decision aids, or email/direct notifications as being useful sources. 1.9 1.7 1.8 1.9 1.8 1.6 1.8 1.6 1.2 1.4 0.7 1.7 1.3 1.3 0.3 1.1 1.4 1.1 0.9 1.1 1.1 0.9 0.4 0.2 0.1 1.0 0.1 0.6 00.511.522.5 State & Federal Agencies Professional Organization Manager's Observations UF/IFAS extension Weed professionals TAME project Land Manager's Advice Pamphlets/ Bulletins Video/CD's Demonstration plots Software/ Decision aids Website/ Internet E-mail Other media Specified Average Rating Agricultural Managers Park Managers Figure 4-2. Usefulness rating of informa tion sources and media by professional land managers in Florida

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50 Table 4-11. Usefulness of information receiv ed by professional land managers in South Florida. Park Managers Agricultural Managers Source Useful Somewhat Useful Not Useful Useful Somewhat Useful Not Useful Percent of Respondents State/federal agencies 881024126 33 Professional organizations 771953720 43 Land mgr. observations 791924719 34 UF/IFAS extension 881026116 23 Weed professionals 79183524 44 TAME Melaleuca 63307137 80 Land mgr. advice 811544720 33 Pamphlets or bulletins 623342641 33 Video cassettes or CDs 433621147 79 Area demonstration plots 532918021 79 Computer software 144343014 86 Website/Internet 791564016 44 E-mail/direct notification 473715014 86 Other information source 752502121 57 Costs for Melaleuca Control Managers were asked to indicate the cost s incurred during 2003 for the control of Melaleuca within the categories of contract services, labor (including wages and benefits), equipment (fuel, ma intenance, and rental), herbic ides, and indirect costs (such as administration and overhead). The total annual cost for controlling Melaleuca for surveyed park/preserve ma nagers was $10.87 (Mn.). This included $8.07 Mn. for contract services, $837,000 for labor co sts, $796,000 for herbicides, $308,000 for equipment, $330,000 for indirect costs, and $528,000 for costs miscellaneous other costs (Table 4-12). Surveyed agricultural ma nagers reported spending $205,000 in 2003 to control Melaleuca with $130,000 for contract serv ices, $29,000 for labor, $22,000 for herbicides, $18,000 on equipment, and $5950 on i ndirect costs. If these numbers are

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51 expanded to represent all ag ricultural managers in Sout h Florida, a total of $1.18 Mn is estimated to have been spent by these managers on controlling Melaleuca in 2003. Table 4-12. Costs for Melaleuca control reported by professional land managers in Florida, 2003. Park Managers Agricultural Managers Expense # Sum ($) Mean ($)Max ($) #Sum ($) Mean ($) Max ($) Contract services 34 8,066,544237,2514,060,0008129,90016,238100,000 Labor 29 837,47028,878400,0001728,9751,70420,000 Equipment 26 308,42811,863225,0001817,8559925,000 Herbicides 33 796,40124,133425,0001921,6101,13715,000 Indirect 19 329,77017,356110,00055,9501,1905,000 Other 7 527,50075,357500,0001500500500 Total 10,866,113204,790 Managers were also asked to indicate expe nses for any special equipment or heavy machinery purchased since 1990 specifically to control Melaleuca It is important to note that these expenses may be partly captured in the previous section under annual costs for equipment expenditures. Among park/prese rve managers surveyed, 28% reported spending a total of $1.44 Mn for special eq uipment, with a maximum expenditure of $1.20 Mn, as shown in Table 4-13. Some 7% of agricultural manage rs reported spending $244,000 on special equipment, which would represent a total of $1.40 Mn when expanded to represent the population in the region. Table 4-13. Expenses for special equipment for Melaleuca control by professional managers in Florida. Category Number Mean ($)Sum ($) Maximum ($) Park Managers 2557,5561,438,9001,200,000 Agricultural Managers 337,390243,879130,000 Managers were asked about how costs for controlling Melaleuca on their land had changed over the past five years; whether th ey had increased, decreased or remained the same. If there had been a change, they were asked to indicate the percentage change

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52 (Table 4-14). Among park/preserve managers, 21% indicated that costs had increased, 26% indicated that costs decreased, and 32% indicated no change. Of those who indicated that costs had incr eased, the average estimated ch ange was 253 percent, while for those who said costs had decreased, the estimated average decline was 117 percent. For agricultural managers, 11% indicated the costs had increased, 9% indicated a decrease and 41% indicated that costs had st ayed about the same. For those indicating a change in costs, the average increase was 81% and the average decrease was 87%. These results suggest that costs for Melaleuca control may be increasing more for park/preserve managers than for agricultura l land managers. A plausible explanation could be the fact that most park/preserv e managers are managing sensitive ecosystems and are mandated to control invasive plants such as Melaleuca in order to keep their management area in a more naturally pristi ne state. Many agricultural managers do not seem to think that Melaleuca is much of a problem so they are probably less interested in removing it, along with the fact that some mangers find that it sometimes provides benefits for their operations. Table 4-14. Melaleuca treatment cost trends reported by professional land managers in Florida. Park Managers Agricultural Managers Trend Number Percent Average Change (%) NumberPercent Average Change (%) Increased 13212531111 81 Decreased 162611799 87 Unchanged 20324041 Don't know trend 13213738 Impacts of Melaleuca Information was sought from managers regarding any negative impacts that Melaleuca had on their land and management over the past five years. The first part of

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53 the question provided the responde nts with a list of options as well as giving them the opportunity to specify any othe r adverse impacts. A second pa rt of the question sought to quantify the impact in terms of the percen tage change in func tion. Among park/preserve managers, 88 percent of those who indicated any impact reported that Melaleuca had impaired the ecological function of their ma nagement area, while 35 percent indicated a reduction in the recreational us e or value of their land (Table 4-15). A small number of park/preserve managers reported other impacts such as increased fire danger, restriction of necessary clearances, and smoke manageme nt issues with prescribed burns. Among agricultural land managers who answered this ques tion, 59% indicated that Melaleuca had reduced their landÂ’s agri cultural productivity, while 39% said it impaired ecological function of their land and dimini shed its recreational use, an d 20% said that their land market values were reduced (Table 4-15). Some of the other negative impacts listed included allergies caused by pollen and various maintenance problems such as damage by falling trees to fences. Table 4-15. Negative impacts of Melaleuca reported by professional land managers in Florida. Park Managers Agricultural Managers Impact NumberPercentNumberPercent Reduced Agricultural Productivity 002459 Lowered Market Value 00820 Impaired ecological function 35881639 Diminished recreational use 14351639 Other impacts 410820 As a follow-up, managers were asked to es timate the percentage change in value or utility due to Melaleuca infestation. Park/preserve managers estimated that the loss of ecological function and recreational use aver aged 23 %, while agricultural managers

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54 estimated that Melaleuca had caused an average loss of 25 % in recreational use and 24% in agricultural productivity (Table 4-16). Table 4-16. Reduction in utility due to Melaleuca infestation reported by professional land managers. Park Managers Agricultural Managers Impact # Mean (%) Min (%) Max (%) # Mean (%) Min (%) Max (%) Reduced Agricultural Productivity 01824 3100 Lowered Market Value 0611 520 Impaired Ecological Function 242311001122 150 Diminished Recreational Use 82311001225 5100 Other Impact 1303030343 5100 Annual Income or Budget and Comparis on of Reported Melaleuca Control Expenses Professional managers were as ked to indicate their gross income from agricultural operations or their agencyÂ’s budget for land management activities for the year 2003, or to indicate the appropriate ra nge of values (Table 4-17). A small percentage of park/preserve managers (16%) reported th eir actual budgets, whic h totaled $9.1 Mn, and averaged $650,000. Among park preserve mana gers, 30% indicated their budget was less than $50,000, 7% said it was within th e range of $50,001-$99,999, 11% indicated it was $100,000 to $249,999, 9% said it was $250,000 to $499,999 range, 5% said it was $500,000 to $999,999, and 29% indicated thei r annual income/budget was $1,000,000 or more. Among agricultural managers, 10% reported actual inco me totaling $7.83 Mn. Some 55% indicated their budget wa s less than $50,000, 6% had $50,001 to $99,999, 12% had $100,000 to $249,999, 2% had $250,000 to $499,999, 3% had $500,000 to $999,999, and 6% had $1,000,000 or more Reported expenses for the control of Melaleuca were compared to reported income or budget in order to gauge the re lative level of effort allocate d to this effort. If managers

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55 chose to write in their income, that exact figure was used in the comparison., however, if their income/budget was reported for a range of values, then the midpoint for that range was used, and for the highest and lowest ra nges (less than $50,000, $1 million or more) $25,000 and $1.5 million were used, respectively. Only managers who reported both expenses and budget/income information could be used for this analysis. The analysis revealed that on average 38 % of park managersÂ’ budget was expended on control measures for Melaleuca as a weighted average. For some managers, reported expenses were as much as 3 to 8 times more than thei r budget. A few of the respondents indicated that less than 1% of their inco me/budget was used on controlling Melaleuca These outliers may be due to reporting errors or ma y simply be due to the fact that some agencies/operations are involve d in deficit spending, i.e. sp ending more than their budget provides. Table 4-17. Annual income or budget for land management by south Florida professional managers, 2003. Park Managers Agricultural Managers Income/Budget Range Number Percent Number Percent Less than $50,000 173010555 $50,001--$99,999 47126 $100,000--$249,999 6112212 $250,000--$499,999 5932 $500,000--$999,999 3553 $1,000,000 or more 1629126 Don't know 593217 Approximate Amount Reported Number Mean Sum Max Park Managers 14650,3869,105,4004,385,000 Agricultural Managers 46170,2137,829,7952,450,000 For agricultural managers, an average of 4% of their income was spent controlling Melaleuca The majority of these managers fe ll into the 1 to 5% range, and some

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56 reported their control expenses were less than one percent, however, some indicated that 60 to 100% of their income went to controlling Melaleuca Results for Residents Invasive Plant Awareness Citizen awareness of non-native flora and in the state of Florid a is an important issue for the management of invasive plants. In the resident survey, a series of questions were included to gauge the publicÂ’s level of knowledge about invasive plants generally, and Melaleuca in particular. The vast majority of the respondents (91%) indicated they were aware that some plants and trees are not native to the State. Nearly as many (89%) indicated they were aware that non-native plan ts could harm local in digenous plants. A strong majority (71%) responde d that they could recognize Melaleuca and an equal percentage indicated that they were aware it was not native to Florida (Table 4-18). Table 4-18. Awareness of Melaleuca and invasive plants by Florida residents. Number Percent Awareness Issue No Yes No Yes Aware some plants are not native to Florida 85898 9 91 Aware non-natives can cause harm 109875 11 89 Can recognize Melaleuca 288689 30 71 Aware Melaleuca isn't native to Florida 280700 29 72 Currently have Melaleuca on property 92137 96 4 Amount of Melaleuca on Property When residents were asked if they had any Melaleuca on their property, only 4% indicated in the affirmative. Of those who had Melaleuca 31% indicated they had only one tree, 16% had two to five trees, and 31% had six to 20 trees Three percent of residents with Melaleuca had one-quarter to one-half of an acre of land infested, 9% had one to four acres, and 6% indicated they had five or more acres of Melaleuca on their property (Table 4-19).

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57 Table 4-19. Amount of Melaleuca on property of Florida residents. Trees or acres Number Percent One tree 1031 Two-five trees 516 Six-20 trees 1031 0.25 acre 13 0.5 acre 13 1-4 acres 39 5 + acres 26 Use of Control Methods for Melaleuca The respondents who stated that they had Melaleuca on their property were asked to indicate which, if any, of the listed control methods they were currently using. Some 84% of residents indicated they had not us ed any control measur es (Table 4-20). Mechanical controls were used by 12 percen t, foliar/soil-applied herbicides or stump treatment were used by 3% each, while 1% i ndicated they had used hack and squirt, biological control, or biological co mbined with some other control. Table 4-20. Methods used for Melaleuca control by Florida residents, and interest in more inform ation about control methods. Methods Used Interested in Learning About Method Number Percent Number Percent Mechanical 23121350 Foliar/Soil herbicides 531869 Hack and Squirt 111662 Felling + Herbicide 531869 Biological Control 212181 Biological + Other 211662 Other Methods 00831 No controls used 15784 The respondents who had Melaleuca were also questioned regarding control methods they would be interested to learn more about. There was a very high level of interest in learning more about biological controls, with 81% of respondents expressing

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58 such an interest (Table 4-20). A majority of respondents were also interested in learning more about foliar/soil-applied he rbicides (69%), stump treatment (69%), hack and squirt (62%), and biological control co mbined with other methods ( 62%). Interest was lower for mechanical controls (50%). Some 31% indicat ed they were interested in some other method of control, however, none specified what the other methods might be. Barriers to Controlling Melaleuca Residents were given a list of factors that potentially limit their ability to control Melaleuca and asked to indicate which of those f actors applied in their case. Of those respondents who indicated any barrier, 56% said that Melaleuca was not a problem, 20% did not care, 19% were afraid of or dislik ed using chemicals, 15% did not know how to use controls, 13% lacked the necessary equi pment and 10 percent gave other reasons (Table 4-21, Figure 4-3). Table 4-21. Barriers to controlling Melaleuca by Florida residents. Barrier Number Percent Not a problem 8056 Don't care 2920 Infestations too small 96 Infestations too large 128 Controls won't work 53 Don't know how to use controls 2115 No time to use controls 96 Afraid of harm to other plants 64 Afraid of or dislike using chemicals 2819 Infestation inaccessible 96 Lack equipment 1813 Environmental regulations 32 No cost sharing 32 Controls too expensive 53 Other reason 1510

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59 Information Sources for Melaleuca Control Residents were given a list and asked to indicate which sources and types of media they had received information from or on the control of Melaleuca (Table 4-22). The most common source of information was newspaper, reported by 59% of those responding to this question, followed by local/nat ional news (47%), and state and federal agencies (42%). Other sources were public television (29% ), pamphlets/bulletins (28%), UF/IFAS extension (27%), w eed professionals (17%), a nd professional organizations (12%). Some miscellaneous other sources mentioned by 17% of re spondents included word of mouth, park or garden club tour s, public speakers, personal research, or educational classes. Finally, only 1% of respondents indicated that they had received information from the TAME Melaleuca project. Table 4-22. Sources of information on Melaleuca received by Florida residents. Source Number Percent State and federal agencies 15242 Professional organizations 4412 Land manger observations 206 UF/IFAS extension 9627 Weed professionals 6117 TAME Melaleuca 41 Land manager advice 236 Pamphlets or bulletins 16628 Video cassettes or CDs 00 Area demonstration plots 203 Computer software 10 Website/Internet 275 E-mail/direct notification 203 Local/national news 28347 Newspapers 35359 Public television 17629 Other source(s) 10317

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60 Expenses for Melaleuca Control Residents were asked to indicate ho w much they had spent on controlling Melaleuca since owning their present prope rty, or during the period 1990-2003, by choosing the appropriate ra nge of values or by estimating the amount if their expenditures exceeded $500. As shown in Ta ble 4-23, 93% of residents indicated they had spent $0-$49, and it is most likely, gi ven previous data, that the majority of respondents in this category probably paid zero. One per cent of respondents indicated that they had spent $50 to $99. Nearly 2% spent $100 to $249 and the same number spent between $250 and $500. Slightly over 2% of respondents spent more than $500 on Melaleuca control. For t hose reporting expenses over $500, the average amount was $1,992, representing a total of $11,950. If these numbers are expanded to represent the entire population of households in South Flor ida, an estimated $15.3 million was spent on Melaleuca control. Table 4-23. Expenses for Melaleuca control by Florida residents, 2003. Expense Range Number Percent $0-$49 38093 $50-$99 41 $100-$249 72 $250-$500 72 $500+ 92 Impacts on Property Values Residents were asked to indi cate whether and by how much Melaleuca had negatively affected their property value. As shown in Table 4-24, 5% reported that Melaleuca had negatively affected their property value, and that values were reduced by an average of 18 percent. However, the majority (95%) said it had not affected their property value.

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61 Table 4-24. Negative effect of Melaleuca on property value of Florida residents. Effect Number Percent No 44095 Yes 245 Number 11 Mean (%) 18 If Yes, amount specified (%) Max (%) 50 Willingness to Pay for Melaleuca Removal/Eradication Residents were also asked to indicate th e dollar amount they would be willing to pay to have Melaleuca removed or eradicated from their property. If respondents indicated they were willing to pay more than $500, then they were asked to estimate the amount. As shown in Table 4-25, 74% of reside nts indicated they would be willing to spend $0 to $49, however, since many residents previously indicated Melaleuca was not a problem for them, the majority of responde nts for this category likely would choose $0. Only 11% indicated they were willing to spend $50 to $99, 6% would pay $100 to $249, 7% would pay $250 to $500, and 2% would pay more than $500. Of those respondents in the last category, the amount they would be willing to pay averaged $1,500. When these numbers are expanded to represent the populat ion of households in South Florida it is estimated that residents would be willi ng to spend a total of $13.7 Mn to have Melaleuca removed from their property, which is simila r to the estimated amount actually spent (see above).

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62 Table 4-25. Willingness to pay for removal of Melaleuca from property by Florida residents. Expense Range Number Percent $0-$49 22474 $50-$99 3411 $100-$249 196 $250-$500 207 $500+ 52 Number 3 Sum 4,500 Mean 1,500 If more than $500, amount specified Max 2,500 Impacts of Melaleuca on Outdoor Enjoyment Residents were asked about the number of days per year they spent in various outdoor recreational activities, and how Melaleuca has affected their enjoyment of the outdoors. Residents reported a total of 8,790 days per year observing/photographing wildlife, 8,132 days for boating or ATV activ ities, 6,263 days for freshwater fishing, 3,434 days for camping/hiking, 601 days for hun ting, and 22,475 days for other activities such as golf, jogging, cycling, walking, ga rdening, tennis, swimming, and saltwater fishing (Table 4-26). When asked about how Melaleuca had affected their enjoyment of the outdoors, 77% indicated that it had not a ffected them and 23% said it had (Table 427). Furthermore, 95% of those affected said it had negatively affected their enjoyment of the outdoors, while only 5% indicated it had positively affected them.

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63 Table 4-26. Days of annual outdoo r recreation activity reported by south Florida residents, 2003. Activity Number Sum Mean Max Wildlife observation/ photography 2618,79034365 Boating/ ATV 3048,13227200 Camping/ Hiking 2423,43414150 Freshwater fishing 6,263 Hunting 496011275 Other Activity 20722,8741111,000 Table 4-27. Effect of Melaleuca on outdoor enjoyment by Florida residents. Response Number Percent No 59877 Yes 17923 If Yes--Negative Effect 17995 If Yes--Positive Effect 95 Willingness to Pay to Reduce Melaleuca in Outdoor Activity Areas Residents were asked how much they would be willing to pay (per visit) to reduce Melaleuca in areas where they engaged in outdoo r activities. They were given several ranges of amounts, and if they were willing to pay more than $25 per visit were asked to estimate the amount. Some 44% of respondent s indicated they were willing to pay nothing, 8% would pay something less than $1 per visit, 27% would pay $1 to $4, 9% would pay $5 to $9, 7% would pay $10 to $15, 4% would pay $16 to $25, and 1% would be willing to pay more than $25 (Table 428). When these numbers are expanded to represent the population of households in Sout h Florida, these residents would be willing to pay an estimated total of $1.35 million to reduce Melaleuca in the areas where they engage in outdoor activities.

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64 Table 4-28. Willingness to pay per visit to reduce Melaleuca in recreational areas by Florida residents. Expense Range Number Percent $0 27544 $0-$1 48 8 $1-$4 171 27 $5-$9 58 9 $10-$15 42 7 $16-$25 23 4 $25 + 9 1 Count 5 Sum $500 Mean $100 If more than $25 estimated amount Max $200 Respondent Demographics Demographic information such as age, gender, property ownership, household size, and income were collected as part of this survey, to help understa nd factors influencing attitudes and behavior toward Melaleuca and other invasive plants. This information is summarized in Table 4-29. In regard to le ngth of residency, 63% had lived in their current location for more than five years, 33% had lived there for one to five years, and 4% had lived there less than one year. Regarding property ownership, 89% of respondents indicated they owne d their home, and 2% owned agricultural, forestry or other natural land in Florida. Some 57% of residents were male and 43% were female. The average year of birth was 1947, the olde st respondentÂ’s year of birth was 1911 and the youngest was 1985. Regarding education leve l, 14% had a high school diploma or its equivalent, 11% had completed a technical/trade school, 26% had some college education or an AA degree, 23% had a bachelorÂ’s degree, and 23% had a gradua te or professional degree. Some 80% of respondents indicated they had voted in a state or local election in the last three years. A household size of 2 people was reported by 91% of respondents.

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65 Regarding household income before taxe s, 5% made less than $10,000, 7% received $10,000 to $19,999, 12% received $20,000 to $29,999, 8% received $30,000-$39,999, 16% received $40,000 to $49,999, 6% received $50,000 to $59,999, 15% received $60,000 to $79,999, 12% received $80,000 to $99,999 range, and 20% indicated they made $100,000 or more.

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66 Table 4-29. Demographics characteristics of surveyed south Florida residents, 2003. Variable Level Number Percent Less than 1 year 33 4 1-5 years 309 33 Residency duration 5+ years 584 63 Lease 104 11 Residence ownership Own 827 89 Female 399 43 Gender Male 524 57 892 Mean 1947 Year of birth Min/Max 1911/1985 Less than high school diploma 26 3 High school diploma or equivalent 132 14 Some college or AA degree 241 26 Technical/Trade School 102 11 BachelorÂ’s Degree 214 23 Education level Graduate/Professional Degree 210 23 No 926 98 Ownership of 25 or more acres in Florida Yes 19 2 No 183 20 Voted in state or local Election in Past 2 Years Yes 757 81 921 Number of people per household Mean 2.4 Less than $10,000 37 5 $10,000-$19,999 52 7 $20,000-$29,999 89 12 $30,000-$39,999 60 8 $40,000-$49,999 121 16 $50,000-$59,999 47 6 $60,000-$79,999 116 15 $80,000-$99,999 89 12 Household income before Taxes $100,000+ 149 20

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67 CHAPTER 5 BENEFIT COST ANALYSIS The primary data used for this analysis were gathered by the previously discussed mail questionnaires; however, some additional da ta were gathered from other sources. After the survey data and the additional da ta gathered were verified, analysis was conducted to ascertain the bene fits and costs of treating Melaleuca in South Florida during the year 2003. This task included delineating the moneta ry values associated with a loss in ecological function due to Melaleuca infestation. Due to time constraints, monetary values specific to South Florida ecosystems could not be generated by this research. However, Constanza et al. (1997) provides the average gl obal values of ecosystem services based upon a synthesis of previous work. The analysis provides estimated annual values for ecosystem services per unit area by ecosystem type. This research will utilize these values assess a monetary va lue to ecosystem function gains from the treatment of Melaleuca Due to the fact that park/pre serve managers indicated that Melaleuca diminished the recreational use of the land they mana ged, a monetary value was assessed to the losses in recreational value that were avoided by the treatment of the infested areas. The Florida Department of Environmental Prot ection (FDEP) Divisi on of Recreation and Parks provided an estimate of the direct economic impact of the state park system (Baxley, pers. comm.). The National Park Service and Florida State parkÂ’s economic impact of visitor spending at parks are ba sed on the Money Generation Model 2 (MGM2)

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68 developed at Michigan State University (MGM2 2003). The analysis provides information as to the number of days vi sited by both local and non-local visitors, the amount of money spent per day, the jobs created, tax revenue generated, the output (revenue) generated by the parks, and othe r economic impacts generated by visitor spending. Calculation of Benefits This analysis focuses on valuing benef its to ecological function, agricultural productivity, agricultural land market va lue, and recreationa l benefits from Melaleuca treatments on public and privately held lands. It is assumed that benefits can only accrue in areas where Melaleuca has actually been killed and acc rue immediately after treatment and that a year of benefits accrues regardless of what time of the timing of treatment. In addition it is important to note that just because an infestation of Melaleuca is treated once does not mean that the job is done. Due to the tenacity of the species, multiple follow up treatments are usually necessary for permanent control to be achieved. Annual benefits may be diminished if sufficient fo llow up treatments are not implemented. A model was developed that relates the areas of Melaleuca treated on specific categories of land to a specific ecosystem va lue to calculate the benefits accruing to that land. The equations used to determine the benefits of Melaleuca control are as follows: 90 10 445 10 (5-1) EB = R Ie ((Aj/Mj) (CxjDx)) + R It F ((Ak/Mk) (CxkDx)) j=1 x=1 k=1 x=1 445 6 (5-2) APB = R P Ib F ((Ak/Mk) (Cxk)), k=1 x=3 445 6 (5-3) MVB = R V Im F ((Ak/Mk) (Cxk)), k=1 x=3

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69 90 (5-4) RB = R Y Ir (Aj/Mj) (Cx1j))/L, j=1 where the dependent variable EB represen ts the ecosystem benefits, the dependent variable APB represents the agricultural pr oductivity benefits, the dependent variable MVB represents the agricultural land mark et value benefits, and RB represents the recreational benefits. Cx is the acreage of land classified for a specific use (x1Â…x10), as reported by each individual park/preserve manage r (j) or agricultural manager (k). Each x value corresponds directly to the land use classification lis ting from the survey, where x1 represents land used as park/preserve, x2 represents right of way, x3 represents pasture/rangeland, x4 is crop land, x5 is fruit/citrus grove, x6 is nursery, x7 is forest, x8 is wetlands, x9 is lakeshore, and x10 is other uses. The variable M represents the total management acreage reported by each park/preserve manager (j) or agricultural manager (k), A is the acreage of Melaleuca treated as reported by each park manager (j) or agricultural manager (k), and R is the effec tive rate of treatment. The variable I, represents the percentage re duction in value reported aver aged across responding park and agricultural managers to ecosystem se rvices, agricultural pr oductivity, land market value or recreational use of la nd reported by park managers ( noted by the subscripts e and r) and agricultural managers (noted by subs cripts t, b, and m) as matched to the corresponding equation. The variable F is the expansion factor used to expand the sample results of agricultural manage rs to represent th e entire population, Dx is the ecosystem value adjusted for inflation from Costanza et al. (1997), P represents the average market value (cash receipts per ac re of land in agricultural production) of agricultural products produced in the 10 county survey region V represents the average

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70 market value of land and buildings per acre in agricultural production in the 10 county survey region, Y represents the total economic output of all of the st ate parks, and two of the major national parks in the survey area, and L represents the total area of park/conservation land in the 10 county survey region as reported by the Florida Natural Areas Inventory (FNAI 2005). Ecosystem Benefits In equation 5-1, the division of the Cx term by the M term yields the proportion that indicates how much of the managerÂ’s land area is de voted to particular uses. The percentage this calculation yields is then multiplied by the acreage of Melaleuca treated, represented by A, as reported by the park ma nager (j) and the agricultural manager (k). This part of the equation is made necessary due to the fact that th e professional managers separately reported their land ar eas managed and the areas of Melaleuca that were treated. That is to say, based upon the inform ation gathered in the survey, there was no delineation as to the land use classification of the infested area treated. Therefore, it became necessary to make the assu mption that the reported area of Melaleuca treated was proportionally distributed among the nine po ssible land use designa tions reported by the individual managers. For example, if a ma nager reported that they managed 120 acres of pasture or rangeland and 30 acres of cropl and, and that they treated 60 acres of Melaleuca on their management site, then 48 acres of the Melaleuca was assumed to be treated on rangeland while 12 acres was treated on cropland. This assumption allows for the areas of Melaleuca treated to be broken down by land use classification into the nine possible classifications, which in turn, allows for an ecosystem function value to be properly assigned to each land use classification. In equation 5-1 all land us e classifications are considered, due to the fact that most terres trial areas provide some sort of ecological

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71 function, even if it is somewhat diminished. The Costanza et al. value assigned to the proper land use classification builds in an allowance for any diminished value in ecological function. For example, the ecologi cal function of cropla nd is only valued at $108/hectare/year, while the function of we tlands is valued at $17,393/hectare/year. As mentioned earlier, the tenacity of Melaleuca makes it difficult to kill. After speaking with vegetation management e xperts from the South Florida Water Management District and Ever glades National Park, it was determined that the minimum rate of kill to be reasonably expected after properly treating Melaleuca was approximately 90 percent (Laroche and Tayl or, pers. comm.). When contractors are hired to go into an area and treat a Melaleuca infestation, they are contractually obligated to guarantee that the existing infestation will be reduced by at least 90 percent. Therefore the R variable represents the effective rate of treatment a nd is a constant .90. This adjustment is made to the area of Melaleuca treated, reported by managers, to allow for the most realistic outcome of treatment to be represented within this benefit equation. The variable Dx represents the ecosystem valu e described by Costanza et al. (1997) that is assigned to the corresponding land use classification from the survey. Costanza et al. report their va lues in 1994 U.S. dollars per hectare which were adjusted for inflation to reflect current 2003 dollars using the GDP implicit price deflator 1.176 as provided by the United State Department of Commerce (USDOC 2006). Additionally, the treatment area figures reported by the mana gers in acres were converted to hectares. Costanza et al. provides a value for land gene rally classified as terrestrial, but also provides values for specific subcategories of land such as, forest, grass/rangelands, wetlands, lakes/rivers, and cropland. The land use categories from the survey were

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72 matched up with a terrestrial biome value so as to provide a dollar value per hectare for the function of that ecosystem. Table 5-1 s hows the Costanza et al. values adjusted for inflation and assigns those valu es with the corresponding land use classifications from the survey. As shown below, there are six po ssible amounts and they are applied to the 10 particular land use classifica tions reported by managers. Table 5-1. Ecosystem Values for Su rveyed Land Use Classifications. Ecosystem Classification Value adjusted for Inflation using GDP Implicit Price Deflator ($/ha/year) Corresponding Land Use from Survey Terrestrial 946Right of way, Other Forest 1,140Park/preserve, Forest Grass/rangelands 273Pasture/rangeland Wetlands 17,393Mitigation area/constructed wetland Lakes/rivers 9,997Lakefront Cropland 108Crop, Fruit/citrus grove, Nursery The next term, I (with the subscript e fo r park managers and t for agricultural managers) represents the value for average ne gative impact to ecological function caused by Melaleuca as reported by professional land managers In the surveys, managers were asked to indicate how their operations had b een negatively impacted in the areas of agricultural productivity land market value, ecological f unctions, and/or recreational use as a result of Melaleuca infestations. None of the pa rk/preserve respondents indicated any negative impacts to the agricultural pr oductivity or market value of their land. Therefore, these negative impacts were not a pplied to any of the equations using their information. The responses were then app lied to the land use classifications and are reflected in Table 5-2. Ma nagerÂ’s perceptions are refl ected by applying the average negative impact percentage to th e benefit gained by treatment of Melaleuca on each land use classification. This fact or is an important addition because nobody knows the effect

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73 Melaleuca has on the land better than those who ma nage it and reflects the losses that can be avoided by treating Melaleuca Table 5-2. Average Negative Impact Values for Surveyed Land Use Classifications. Impact Average Reduction Park Managers (%) Average Reduction Agricultural Managers (%) Corresponding Land Use Classification Reduced Agricultural Productivity N/A24Pasture, Crop, Fruit, Nursery Lowered Market Value N/A11Pasture, Crop, Fruit, Nursery Reduced Ecological Function 2322All Land Classifications Diminished Recreational Use 2325Park/Preserve Finally, the equation for agricultural managers also includes the term F which is an expansion factor used only when applying the data collected for agricultural managers to the equation. Since only a sample of ag ricultural managers were surveyed, it was necessary to expand the sample results to represent the population of agricultural managers in South Florida. Expansion fact ors can be devised based on either the land areas surveyed or the number of people su rveyed. In this cas e it was based on the number of managers surveyed. The popul ation was 11,500 and the sample size was 2,000. Dividing the population size by the samp le size yields an expansion factor of 5.75. This calculation assumes that the sample data gathered was re presentative of the population. Agricultural Land Productivity Benefits Survey results indicated that only a small portion of the total area of Melaleuca treated occurs on agricultural land. However, in order to conduct a thorough analysis, as many factors as possible are considered in ca lculating a benefit value. Equation 5-2 is basically the same as the equation (5-1) used to calculate ecosystem benefits, with the

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74 exception that the land areas reported and values applied are changed to reflect the effects on agricultural productivity and not the ecological function a nd it only considers the data gathered from agricultural managers. In esse nce the P variable repl aces the value of the ecological function seen in the ecosystem benefits equation and is equal to $1,034 per acre as reported by the 2002 Agricultu ral Census data (USDA-NASS 2002). Additionally, the average ne gative impact value, Ib, is reflective of the average percentage reduction in agri cultural productivity reporte d by agricultural managers (24%), shown in Table 5-2. In this case onl y areas treated on agriculturally classified land (range (x3), crop (x4), fruit (x5), or nursery (x6)) by agricu ltural managers are considered since park/preserve managers repo rted that they managed very few acres of land classified as being used for agricultural purposes. Agricultural Land Market Value Benefits A monetary value was estimated for the benefits accruing to agricultural land market values due to the treatment of Melaleuca on those agricultural lands. As is the case with the previous equations (5-1 and 5-2) the variables in equation 5-3 are generally the same; and this equation also considers on ly the data collected from agricultural managers. Therefore, the areas reported for land uses Cxk, acres of Melaleuca treated Ak, total land management area Mk, and average negative impact value Im,(which is equal to 11% as shown in Table 5-2) are specific to agricultural managers a nd their perceptions of the effects of Melaleuca on land market values. Additiona lly, the variable V is equal to $7,017 per acre, according the 2002 Agricult ural Census data (USDA-NASS 2002). Recreation Benefits Not only does land set aside as parks or pr eserves play an invaluable role in allowing vital ecological processes to be carried out, but it also provides natural areas that

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75 allow for humans to interact with nature a nd gain some measure of satisfaction from recreation. Many individuals w ould probably indicate that the enjoyment they gain from outdoor recreation is not completely attribut ed to the ecological functions taking place on the land, and that some measure of enjoyment is gained from the existence of the land and the availability of the land to provide th em with a place to experience the outdoors. Therefore, it is imperative to find a way to measure the recreational value that would be lost due to a Melaleuca infestation on a park or preserve. Equation 5-4 shows that the rate of treatment is found by dividing Cxj by Mj then multiplying that by Aj, and by the effective rate of tr eatment R (0.9). The Y variable represents the total ec onomic output for the year 2003 of a ll of the state parks and two of the major national parks (Everglades National Park and Big Cypress National Preserve) in the survey region as generated by th e Money Generation Model 2 (MGM2) and is equal to $305,670,188 (MGM2 2003). Unfortunately, due to technical difficulties with the website that publishes this information, at the time of this publication, the economic output of other federal parks and preserves coul d not be collected. It is important to note that the inclusion of the economic output s of these other parks would drive the recreational benefit value highe r. The equation accounts for the percentage loss in the recreational value of pa rk/preserve land due to Melaeluca infestation as reported by professional park/preserve manage rs, therefore, the variable Ir is equal to 23%. Finally, the previously discussed variab les are all divided by the vari able L which represents the total area of park/conser vation lands in the 10 count y region for 2003 (5,275,455 acres) as reported by the Florida Natural Areas I nventory (FNAI) located at Florida State University (FNAI 2005).

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76 Additional Benefits The issue of fire danger associated with dense Melaleuca stands has been documented over the years. The fire danger is not only a serious concern for the Florida ecosystem, but also for the lives and pr operties that are threatened when a Melaleuca fueled fire occurs. Fire-fighting cost es timates have been compiled through suppression bills issued by the Florida Division of Forestry (FDOF). In 1985 and 1989 Melaleuca fueled fires burned nearly 12,000 acres adjacen t to the Dade County Northwest well field at a cost of $25,000 and $21,000, respectively, an d a 1,000 acre fire in Broward County cost approximately $10,000 (Diamond et al. 1991) Costs for municipal fire departments are estimated to be three times that of the FDOF due to their greater manpower requirements and equipment expenditures (Wasil and Lewis pers. comm.). These estimates yield a per acre cost of $2 to $10 for the (FDOF) and $6 to $30 for local municipalities. When the median of the estim ated cost ranges ($6 and $16) are used, and applied to an assumed 12,000 acre fire the calculations yield cost savings estimates (adjusted for inflation using the GDP implic it price deflator) of $97,207 for wildland fire control by the FDOF and $259,219 for local muni cipal fire departments. Table 5-3 shows that the total benefits gained from treating Melaleuca in 2003 were $31,742,298. The benefits that apply to the areas of land reported by park/preserve managers are ecosystem benefits, recrea tional values, and the benefits gained from avoidance of increased fire damages, which are $13.14 million, $9.17 million, and $178,213, respectively for a total of $22.49 million. The benefits of restored ecological function, agricultural productivity, agricultural market value, and a voidance of fire damages apply to Melaleuca treatment areas as reported by agri cultural managers in the amounts of $236,866, $2.15 million, $6.68 million, and $178,213, resp ectively, and yield a total of

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77 $9.24 million. Since there are two categories of managers being considered, the overall avoidance of fire damages AB ($356,426) is di vided between the two categories to yield $178,213 for each managerial category. Finally, the total benefits are reached by adding equations 5-1 through 5-4, along with the additio nal benefits of fire prevention, together to yield: (5-5) TB=EB + RB + APB + MVB + AB, where TB stands for total benefits and AB stands for additional benefits due to fire prevention. Table 5-3. Total Benefits of Melaleuca Control in 2003. Benefit Value ($) Agricultural Productivity 2,146,228 Agricultural Land Market Value 6,675,569 Ecological Function 13,397,685 Recreational Value 703,313 Avoidance of Fire damages 356,426 Total 23,279,221 Calculation of Costs The calculation of costs for this analysis is fairly straightforward since the cost data were gathered by the survey. The followi ng equations denote the different cost data gathered: 90 (5-6) Cp= Hj, j=1 445 (5-7) Ca= F Zk, k=1 1,015 (5-8) Cr= Gi i=1 (5-9) Ct= (C03 + C04)/2,

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78 where, the variable Cp represents park manager costs and is equal to the summation of the responses (Hj) of those managers, Ca represents agricultural manager costs and is equal to summation of those responses (Zk), the variable F represents the previously discussed expansion factor, and Cr are estimated residential cost s for the year 2003 based upon the survey responses (Gi). The methods for that estimation are discussed below. The dependent variable Ct is the TAME Melaleuca budget and the variables C03 and C04 represent the budgets for fis cal years 2003 and 2004 for TAME Melaleuca When the survey responses for the cost figures of park/preserve managers were summed it was calculated that they spent $10.87 million on Melaleuca controls during 2003. The sample of agricultural managers surveyed indicated that they spent $204,790. As mentioned earlier, assuming that the sample of agricultural managers is representative of the population, this cost figure can be e xpanded to represent the whole population of agricultural managers. This calculation reveals that the ag ricultural managers in South Florida spent an es timated $1.18 million on Melaleuca control in 2003. Additionally, the TAME Melaleuca program costs were reported as $820,000 for the 2003 fiscal year (October 1, 2002 to September 31, 2003) and $1,010,000 for the 2004 fiscal year (October 1, 2003 to September 31, 2004) (Silvers pers. com.). Since these fiscal years divide up the calendar year 2003, half of each of the budgets was taken and added together to yield $915,000 as the estimate for the 2003 TAME Melaleuca budget. Cost figures were also gathered from the residential surveys. However, the cost data collected in this survey were gathered by asking respondents to indicate what range of money they had spent on control measur es from 1990 to 2003 or since owning their property and were not as st raightforward as the costs reported by the professional

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79 managers. For example, instead of reporting that they spent $200 in 2003, residents indicated that they spent an amount that fell within the range of $100 to $249 since owning their property. These responses do not allow for a specific control cost figure to be gathered for the year 2003 and require so me additional assumptions and calculations to be made. For the sake of clarity the two issues will be addressed separately. Since the residential survey data was a sample gathered from the population the sample data gathered needed to be expanded to represent the populat ion of residents in South Florida. The survey populatio n was 2,511,141 and the sample size was 5,001. Dividing the population size by th e sample size yields an ex pansion factor of 502.13. For the sake of using a round number the e xpansion factor was rounded to 500 for the residential data. Due to th e fact that respondents indica ted a range of money spent on control efforts one specific figure could not be calculated. Instead three separate figures were calculated to reflect a range of possibi lities. Specifically, low, middle, and high range estimates were calculated to demonstr ate the possible outcomes for the responses gathered. For example, if a respondent indicat ed that they qualified for the categorical cost range of zero to $50, th en the low, medium, and high range possibilities for that respondent were zero, $24.50, or $49, respectivel y. Every person who responded to this question was assigned a low, medium, and hi gh range value. Each categoryÂ’s outcomes were then summed together, thus allowing three different cost scenarios to be demonstrated for residents. These results indicate that $6,909, $31,029, and $68,808 were the raw results from the estimation of the low, middle, a nd high range residential cost scenarios, respectively. The low, middle, and high range numbers were then expanded to $3.45

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80 million, $15.51 million, and 34.40 million, respectiv ely, using the expansion factor of 500, as previously discussed. Due to the fact that the majority of residential respondents responded that they did not have Melaleuca on their property the assumption was made that most of the respondents who indicated the $0 to $49 range were most likely reporting that they had spent $0 on control measures, so this analysis uses the low cost estimates. Additionally, the cost figures must be adjusted to represent the time frame addressed in this analysis. A value must be calculated from th e data gathered to yield the best estimate of the cost figures for 2003. Since the data reported were for a time span of 1990 to 2003 the figures computed above were averaged out over the 14 year period to yield an average dollar amount spent per ye ar. Using the low, middle and high range scenarios as discussed above, resident s are estimated to have spent $246,750, $1.11 million, and $2.46 million respectively on control measures during 2003. Table 5-4 shows that an estimat ed total of $13,207,863 was spent on Melaleuca control measures in 2003. Th erefore total costs (TC) ar e equal to the summation of equations 5-6 through 5-9 and is demonstrated by: (5-10) TC= Cp + Ca + Cr + Ct. Table 5-4. Cost Data for Melaleuca Control in 2003 Group Costs ($) Park Managers 10,866,113 Agricultural Managers 1,180,000 Residents 246,750 TAME Melaleuca 915,000 Total 13,207,863 Calculation of the Benefit-Cost Ratio Given the previous equations and met hodology, the task of calculating a BCR that compares agricultural productiv ity, agricultural land market values, ecological function,

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81 and recreation benefits to control and progr am costs is now very simple. Using the general equation: (5-11) BCR = TB/TC, where the variable BCR represents the benef it-cost ratio and TB and TC represent the total benefits and total costs, respectively, all that has to be done is to enter the appropriate values into the equation to gain an overall BCR for treating Melaleuca As shown in the previous tables, the total benefits gained in the areas of agricultural productivity, agricultural land market valu es, ecological function, and recreational benefits from treating Melaleuca during the year 2003 equal $23,279,221 while the total control and program costs from the same time period amount to $13,207,863. When these values are applied to equation 5-11, th e results yield a bene fit-cost ratio of 1.76. While the total benefit-cost ratio is useful in helping to determine the overall success or failure of a program, the discus sion of the benefit-cost ratios from the subcategories considered in this analysis can also be useful. The categories of survey respondents had very different re sults for the areas occupied by Melaleuca and the areas treated. When the same methodologies used fo r the overall benefit-cost ratio are applied to the subcategories of data, separate be nefit-cost ratios can be determined for park/preserve managers and agricultural ma nagers. The total benefits accruing to park/preserve managers are $14.02 million, while the total costs park/preserve managers reported in the survey were $10.87 million, thus yielding a benefit-cost ratio of 1.29 for park/preserve managers. Total benefits accruing from treatment of Melaleuca on agricultural land are estimated to be $9.24 million. When the cost data reported by agricultural managers are

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82 expanded to represent the population it is estimated that the total costs were $1.18 million. Using equation 5-11, the calculation re veals a benefit-cost ratio of 7.83. This number is relatively high due to the fact that agricultural lands have multiple benefits accruing to them. Agricultural managers also reported lower costs because they have not been treating Melaleuca as aggressively as park manage rs and therefore have a greater marginal value response at this stage of their control efforts. If agricultural managers pursue controls more assertively, it is expected that the marginal value of the benefits from their control efforts will diminish with the greater treatment area. While park/preserve lands also have the multiple benefits of ecological function and recreational value, agricultural lands have agricultural pr oductivity and land market values as well as ecological function accruing to them. Even t hough the ecological benefits that accrue to agricultural lands are greatly diminished as comp ared to lands held in a natural state, the soil and bedrock contained in them still se rve some water filtra tion purposes, however minimal. Therefore, agricultural lands ha ve a relatively larger amount of benefits accruing to them than park/preserve. While the previous statement may be true for the purposes of this analysis, it is imperative to not jump to the conclusion that agricultural lands are simply more valuable than park/p reserve lands. There are benefits such as existence values for parks/preserves that are not considered in this pa rticular analysis and would undoubtedly drive the benefits accruing in those areas higher.

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83 CHAPTER 6 SUMMARY AND CONCLUSIONS Summary This thesis seeks to characterize the current state of the management of Melaleuca in South Florida and determine the benefits and costs of controlling Melaleuca for the year 2003. Previous benefit-cost analyses ha ve primarily focused on the possible benefits and costs associated with the unfettered spread of Melaleuca That kind of research was quite useful in helping to de termine if the benefits to unde rtake control strategies would outweigh the costs. This analysis differs in that it seeks to assign a monetary value to the benefits actually gained on the areas of land invaded by Melaleuca which have been successfully treated and the cost s associated with that trea tment. Instead of conducting an analysis that assumes a hypothetical best or worst case scenario, this analysis seeks to focus on the reality of what is actually ha ppening with the spread and treatment of Melaleuca in South Florida and serves to eval uate policy and management decisions made during this program. After consultations between UF-IFAS, USDA-ARS, and TAME Melaleuca surveys were developed and mailed to professi onal land managers and residents in the 10 southernmost counties of Florida during th e summer of 2004. The surveys for the professional managers were sent to individuals whose manage ment areas were classified as park/preserve or agricultural. A wealth of information was gathered to help gain insight into the current st atus of the war against Melaleuca The benefit-cost analysis specifically used the data that pertained to the land use clas sifications of the management

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84 area, how much Melaleuca was on the land, the area of Melaleuca treated, the costs associated with the treatment, and the negative impacts to the land caused by the Melaleuca infestations as estimated by managers. The response rates for park/preserve and agricultural managers were 32% and 22%, respectively. The responses from park/preserve mana gers revealed th at 619,317 acres of Melaleuca inhabited their management areas, wh ile they treated a total of 84,740 acres during 2003. Based on the fact th at control strategies are not completely effective, a 90% rate of effective removal was applied to th e treatment areas repo rted by park/preserve managers to yield the estimated area of Melaleuca killed as 76,265 acres The total costs associated with these control methods were reported as $10.9 million. The park/preserve managers felt that Melaleuca impaired the ecological functi on and recreational use of the land they managed by an average of 23%. Agricultural managers indicated that a total of 2,134 acres of Melaleuca occurred on their land and that they treated approximately 1,991 acres during the year 2003. When the assumed effective rate of treatment is used it is estimated that approximately 1,701 acres of Melaleuca were killed on agricultural la nds during 2003. The total costs associated with these treatments were approximately $204,790. It should be noted that these figures collected from the sample of agri cultural managers were expanded to reflect the population for the calculation of the bene fit cost ratio(s). The expanded figures indicate that agri cultural managers had an esti mated total of 12,271 acres of Melaleuca occupying their land, while they treated an esti mated 10,868 acres at an estimated cost of $1,180,000 during 2003. Finally, the agricultural managers repor ted that the agricultural

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85 productivity, market value, and ecological func tion of their land had been reduced by an average of 24 percent, 11 percent, and 22 percent, respectively. The majority of the data gathered by the residential survey was directed at gathering information related to the awareness and perceptions of Melaleuca by the residents and therefore much of it was not used in this benefit-cost analysis. However, the cost data collected from the residents wa s used. Residents had the lowest survey response rate at 20 percent. Based on the da ta collected and the methods described in the previous chapter, it was estimated that the re sidents of South Florida spent an estimated $246,750 on Melaleuca control/removal in 2003. Using the information gathered from the mail surveys and other relevant data sources it was determined that the benefit-cost ratio for Melaleuca control in the year 2003 was 1.76. The benefit portion of the rati o was computed by assessing monetary values for the benefits that were gained due to the re stored ecological function of agricultural and park /preserve land, agricultural produc tivity and market value of agricultural land, a nd the recreational use of park/preserve lands where Melaleuca controls had been implemented. The additiona l benefit of avoidance of costs connected with Melaleuca fueled fire control was also consider ed in the benefit equation. The costs were derived from the residential and prof essional survey data along with the TAME Melaleuca program costs which include the cost s associated with this research. Conclusions, Implications, and Policy Recommendations Based upon the results of the surveys it is qu ite apparent that the vast majority of Melaleuca control is still taking place on public land in South Flor ida. As stated in the introduction of this thesis, this phenomenon is most likely due to th e fact that a legal mandate requires public agencies to remove inva sive plants from their management areas.

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86 It may be necessary for the legislature to make the current laws addressing the general public more stringent so as to induce a greater number of private land managers and homeowners to implement Melaleuca controls on their properties. While making the laws stricter is a step in th e right direction, it will also be necessary for the lawmakers to assign specific penalties for those in vi olation of the law and require a uniform enforcement of the laws and penalties. Th is would require increased presence by the enforcement agencies and would certainly re quire a greater amount of time and effort from those agencies. A requirement simila r to those municipalities that call for new construction sites to have Melaleuca trees removed from the pr operty before a certificate of occupancy can be issued may be a useful tool in inducing Melaleuca removal. The results of the benefit-cost analysis support the earlier hypothesis made that this analysis would yield a benefit-cost ratio higher than one. When the benefits from Melaleuca control realized on park /preserve and agricultural land are compared to the costs incurred by those land managers and privat e residents the analysis indicates that the benefits are almost two times gr eater than the costs. It is important to keep in mind that this is not even considering benefits that may be accruing to the private homeowners in South Florida and would only serve to increa se the benefits. Gi ven the resulting costbenefit ratio of 1.76, it can be said that the current policy requiring Melaleuca control is providing a benefit to society in the year 2003. It is interes ting to note that due to the compound effect of having multiple values tied to their land (i.e.-the values gained from the ecological functions, the actual production of agricultural commodities as well as the market value of the land) this analysis indi cates that agricultural lands have a higher benefit-cost ratio than park /preserve lands for treating Melaleuca (7.83 vs. 1.29). Even

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87 without considering the benefits accruing to agricultural land market values, the ratio is still greater for agricultural la nds than park/preserve lands (2 .17 vs. 1.29). Therefore it is recommended that policymakers and public agen cies continue to at least maintain the current levels of funding and control efforts for Melaleuca reduction. Not only should they continue to maintain the current leve ls of funding, but they should also consider increasing funds to help specifically target agricultural managers to persuade them to control Melaleuca on their property. This would se rve to help solve the problem of having Melaleuca spread around private lands, while it is being controlled on public lands, and would also help avoid cross contamin ation from the infested areas to the areas under control. A majority of residents who responded to the survey questions aimed at determining their awareness of Melaleuca indicated that they knew that Melaleuca was not native to Florida and that they knew non-native plants could be harmful (71% and 89%, respectively). However, when the re sidents were later as ked to indicate if Melaleuca effected their enjoyment of the outdoo rs 77% of those who responded to the question indicated that it did not When residents were asked to indicate if they felt that Melaleuca negatively affected their property va lue 95% of those responding to the question indicated that they felt it did not. There seems to be a gap between what people know about Melaleuca and how that knowledge affects th eir desire to take the actions necessary to control it. Acco rding to the survey data th e main sources that provide information on Melaleuca for residents were newspapers and local/national news (59% and 47% of residents who responded to the question, respectively). These may be the outlets that policy makers, environmenta l action groups, and public agencies should

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88 target to help educate the public about how Melaleuca can negatively affect their lives and why they should control it. If people are made aware of th e specific ways the environment (through the loss of native flora a nd fauna and the impairment of necessary ecological functions) and conse quently their lives could be negatively impacted if the spread of this plant is not slowed, then perhap s they would be more likely to take more of a proactive role in its control. Recommendations for Future Work When it comes to evaluating any public policy or program there are a myriad of different areas to consider. Evaluating Melaleuca control is no different. Due to time constraints there were areas that were not addressed by th is research. As mentioned earlier, this research did not address benefits that residents gained from Melaleuca control measures; this would serve to allow managers and policy makers to have a more complete picture of the benefits a nd costs involved with controlling Melaleuca Due to the fact that the mail surveys used for this analysis were generally focused on gaining information for the year 2003, only a small amount of the information gathered showed the progress of Melaleuca control since its beginning in the early 1990s. This analysis only looked at point estimates of the benefits from Melaleuca control. Consequently, these benefit estimates may be greater or lesser due to the fact that averages were often used. It would be very beneficial for a benefitcost analysis to be conducted for the whole lifespan of the eradi cation/control program. This would allow researchers, policy makers, and managers to see patterns that have developed over time and what kind of progress has been made, thus allowing them to adjust their strategies, if necessary.

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89 To date there is no one agency that has accounted for of all Melaleuca infestations and treatment areas. It would be very prudent for research to compile a database of the areas infested and treated each year and the co sts for the treatments. The research should also seek to determine the land use classifica tions of the infestation and treatment areas (i.e.-whether the land is used for park/prese rve, crop production, commercial timber, etc.) so that future researchers would not have to make the assumptions that this research had to use when assigning monetary values for be nefits of treatment. Additionally, it would be useful to ask managers to indicate their estimates of th e functionality regained on land that they have treated for Melaleuca rather than requiring resear chers to make inferences based on managerÂ’s estimates of the negative im pacts of infestations on their land. This analysis assumed that full benefits were ga ined immediately after treatment occurred. Therefore, it would be valuable for research ers to determine the amount of time necessary for full benefits to be realized after successf ul treatment occurs and to quantify the rates at which the full benefits return during that time frame. This would allow for a more accurate picture of the value of the benefits gained from Melaleuca treatment on the various land uses. It should be noted that another roun d of surveys and/or focus groups are scheduled to be conducted at a later date to measure the success/visibility of the TAME Melaleuca program. This could serve as an opportuni ty to gather some of the previously mentioned data so as to conduct an exhaus tive benefit-cost analysis of the overall Melaleuca eradication/control program.

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90 APPENDIX A MELALEUCA MANAGEMENT SURVEY OF PROFESSIONAL LAND MANAGERS This survey is being conducted by the Un iversity of FloridaÂ’s Institute of Food & Agricultural Sciences in partnership w ith the U.S. Department of AgricultureAgricultural Research Service, for th e purpose of examining the impacts of Melaleuca and other invasive plants in Florida. The survey is being mailed to a sample of public and private land managers. Please respond to the following questions, and return the completed questionnaire in the postage paid envelope provided. Your answers will be instrumental in developing successful and co st-efficient methods for better controlling invasive plants. The questions pertain to your operations during 2003, unless otherwise indicated. Please answer only for your property or the management unit(s) under your supervision. Information obtained in this survey will be kept strictly confidential; only averages or totals for all survey resp ondents will be disclosed. Your participation is voluntary and you may decline to answer any question if you do not wish. There is no compensation or anticipated risks for participating in this su rvey. The survey will require about 15 to 30 minutes to complete. If you have any questions about this su rvey, you may contact the investigator: Alan W. Hodges, PO Box 10240, Gaines ville, FL 32611, tel. 352-392-1881 x312, email AWHodges@ufl.edu or the sponsor at USDA-ARS Inva sive Plant Research Laboratory, 3205 College Ave., Ft. Lauderdale, Fl 33314, tel. 954-475-0541, fax 954-476-9196, email csilvers@saa.ars.usda.gov or visit the website: http://tame.ifas.ufl.edu/ For questions about your rights as a research participan t, contact the University of Florida Institutional Review Board at PO Box 112250, Gainesville, FL 32611, telephone 352392-0433. Thank you for your participation!

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91 Contact and Location/Address Information: Name of person filling out form:_____________________________________________ Name of Organization:_____________________________________________________ Street or PO Box:_________________________________________________________ City & zipcode:__________________________________________________________ Telephone number:_______________________________________________________ Florida counties in which land holding(s) under your management are located (list all): ________________________________________________________________________ ________________________________________________________________________ Fiscal Year/Ending Month for annual information reported Check here if information is reported for Jan1. to Dec. 31, 2003; Otherwise, indicate annu al period reported:_____________________________________ 1. Land Ownership. Indicate the land area under your management that is privately owned, publicly owned or leased: Ownership Acres Privately owned ________________ Publicly owned ________________ Privately leased ________________

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92 2. Land Use Enter numbers of acres managed for each of the following land use types: Land Use Type Acres Park or preserve (aquatic or terrestrial) ________________ Right of way (roads, canals, powerlines) ________________ Pasture or rangeland ________________ Crop land ________________ Fruit or citrus grove ________________ Nursery ________________ Forest (commercial timberland) ________________ Mitigation area or constructed wetland ________________ Lakeshore ________________ Other use(s); specify: ________________ Total of all land uses ________________ 3. Factors Affecting Land Management. Rate each of the following factors regarding its influence on your land management decisi ons; check the appropria te box to indicate whether influence is “none” (no influe nce), “moderate”, or “significant”: Influence Factor None Moderate Significant Agency funding Adverse weather conditions Availability of agricultural land Encroachment of urban land uses Foreign or other state competition Cost of inputs or supplies Prices for crops, fruit, livestock Invasive Plants Predators; insect pests Ability to conduct prescribed burns Other factor(s); Specify: ________________________________

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93 4. Area Occupied By Invasive Plants and Area Treated. Estimate the area on your lands currently occupied by each of the following invasive plants and the area that has been treated by any control method(s) between 1990 and 2003: Invasive Plant Total Area Occupied (Acres) Area Treated (Acres) Paper bark or Punk tree ( Melaleuca ) ________________ ______________ Brazilian Pepper ( Schinus ) ________________ ______________ Australian Pine ( Casuarina ) ________________ ______________ Old World Climbing fern ( Lygodium ) ________________ ______________ Cogon grass ( Imperata ) ________________ ______________ Torpedo grass ( Panicum ) ________________ ______________ Tropical Soda Apple ( Solanum ) ________________ ______________ Other plant(s); Specify:___________________ ________________ ______________ 5. Methods Used for Melaeluca control. Indicate the area treated with each of the following methods for control of Melaleuca both last year (2003), and since 1990. Check if Method Used Control Method(s) Used Area Treated 2003 (Acres) Total Area Treated 19902003 (Acres) Mechanical (felling, mowing, tilling, grubbing, disking, etc.) Foliar or soil applied herbicides (aerial or spot application) Girdling and herbicide treatment (“hack & squirt”) Felling and herbicide treatment on cut stump Biological control (beneficial insects) Biological control combined with one or more method(s) Other method(s) used; Specify: ____________________________________ Check here if you have not used any control measures for Melaleuca

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94 6. Intention toUse Melaleuca Control Methods. Indicate whether you plan to continue using or to adopt any of the fo llowing practices for control of Melaleuca and whether you would like to receive more informa tion about its effectiveness and cost. Check if you plan to use or continue using Check if you would like more information Control Methods Mechanical (felling, mowing, tilling, grubbing, discing, etc.) Foliar or soil herbicides (aerial or spot application) Girdling and herbicide treatment (“hack and squirt”) Felling and herbicide treatment on cut stump Biological control (beneficial insects) Biological control combined with one or more other method(s) Other method(s) used; Specify _________________________ 7. Barriers to Controlling Melaleuca Please indicate reasons that may limit your ability to control Melaleuca Check any that apply. Do not have Melaleuca on my property Melaleuca is not a problem for me Don’t care about Melaleuca Infestations are too small Infestations are too large Controls will not work Do not know how to use controls Do not have time to use controls Afraid controls will harm other plants Afraid of/dislike using chemicals Infestation areas are inaccessible Do not have the necessary equipment for controls Environmental regulations prev ent me from using controls There are no cost sharing programs for controls Controls are too expensive Other reason; Specify: ___________________________________

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95 8. Information Sources and Media for Melaleuca Control Indicate what types of information sources and media you have received information about control of Melaleuca and whether this was usef ul? Check all that apply. Information Usefulness Have Received Information Useful Somewhat Useful Not Useful Information Source or Media State and federal Agencies Professional organizations Observation of other land managers UF/IFAS extension information Recommendations by weed p rofessionals TAME Melaleuca project Advice from other land managers Pamphlets or bulletins Video cassettes or CDs Area demonstration plots Computer software decision aids Website / Internet E-mail newsletters or direct notifications Other information source(s) or media; Specify:__________________

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96 9. Annual Costs for Melaleuca Control. Indicate the costs for control of Melaleuca on your land last year (2003) in the categories listed below. Give actual amount or estimate an approximate amount. Expense Type Amount ($) Contract services $____________ Labor (wages & benefits) $____________ Equipment (fuel, maintenance, rental) $____________ Herbicides $____________ Indirect costs (administration, overhead) $____________ Other; (specify)________________________ $____________ Total costs $____________ 10. Expenses for Special Equipment. Indicate the total expense for any special equipment or heavy machinery purch ased specifically to control Melaleuca on your lands since 1990. Total equipment expenditure amount: $__________________ 11. Trends in costs for Melaleuca Control. How have the total costs of Melaleuca control on your lands changed over the past five years? Check appropriate response: Increased Decreased Stayed about the same DonÂ’t know If increased or decreased, indicate by how much: ______ %

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97 12. Impacts of Melaleuca. How has Melaleuca negatively affected your land over the past five years? Check any that appl y, and indicate the percentage change: Check if applies Type of Impact Percent Change (Loss) Reduced agricultural productivity _______% Lowered market value _______% Impaired ecological function _______% Diminished recreational use _______% Other impact(s); Specify: _______% 13. Annual Income/Budget. Indicate your organizationÂ’s gross income from agricultural operations, or your agencyÂ’s budget for land manage ment activities last year (2003). Please give the approxi mate amount or check the range that represents this value. Approximate annual income or budget: $_____________ Less than $50,000 $50,001 to $99,999 $100,000 to $249,999 $250,000 to $499,999 $500,000 to $999,999 $1,000,000 or more DonÂ’t know

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98 Comments. In the space below, please write any comments you may have regarding invasive plant management or the TAME Mela leuca Project. Feel free to address any issues not covered in this questionnaire. ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ Check here if you wish to receive a copy of the study results. by mail by e-mail___________________________________________________ Date survey completed:_________________________ Please return this questionnaire in the envelope provided. Thank you again for your participation.

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99 APPENDIX B MELALEUCA MANAGEMENT SURVEY OF RESIDENTIAL PROPERTIES This survey is being conducted by the Un iversity of FloridaÂ’s Institute of Food & Agricultural Sciences in partnership with the U.S. Department of AgricultureAgricultural Research Service, for th e purpose of examining the impacts of Melaleuca and other invasive plants in Florid a. The survey is being mailed to a sample of the public at large. Please respond to the following questions, and return the completed questi onnaire in the postage-paid envelope provided. Your answers will be instrumental in devel oping successful and co st-efficient methods for better controlling invasive plants. Please answer only for your property. Information obtained in this survey will be kept strictly confidential; only averages or totals for all survey respondents will be disclosed. Your participation is voluntar y and you may decline to answer any question if you do not wish. There is no compensation or anticipated risks for participating in this survey. The survey will require about 15 to 30 minutes to complete. If you have any questions about this survey, you may contact the investigator: Alan W. Hodges, PO Box 10240, Gain esville, FL 32611, tel. 352-392-1881 x312, email AWHodges@ufl.edu or the sponsor at USDA-ARS Invasive Plant Research Laboratory, 3205 College Ave ., Ft. Lauderdale, FL 33314, tel. 954-4750541, fax 954-476-9169, email csilvers@saa.ars.usda.gov or visit the website: http://tame.ifas.ufl.edu/ For questions about your rights as a research participant, contact the University of Florida In stitutional Review Board at PO Box 112250, Gainesville, FL 32611, telephone 352-392-0433. Thank you for your participation! Please turn the page

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100 Este cuestionario esta siendo conducido conjuntamente por el Instituto de Alimentos y Ciencias Agrcolas de la Univer sidad de la Florida (U niversity of Florida Institute of Food & Agricultural Sciences UF /IFAS) y por el Servic io de Investigacin Agrcola del Departamento de Agricultura de los Estados Unidos (U.S. Department of Agriculture-Agricultural Research Service), con el propsito de examinar el impacto de la Melaleuca y otras plantas de tipo i nvasivo en el estado de la Florida. El cuestionario esta siendo enviado por correo al publico en ge neral. Por favor, le pedimos conteste las siguientes preguntas, y regrese el cuestiona rio en el sobre provisto(no requiere de estampillas). Sus respuestas sern instrumentales en el desarrollo de mtodos econmicos, eficientes y exitosos para el me jor control de las plantas invasivas. Por favor conteste solamente con resp ecto a su propiedad. La informacin obtenida a travs de este cuestionario se r mantenida estrictamente confidencial; nicamente los promedios y totales para todos los encuestados sern publicados Su participacin es totalmente voluntaria. Usted puede omitir su respuesta a cualquier pregunta, si as lo desea. No se ofrece ni ngn tipo de remuneracin por participar en la encuesta, ni tampoco se anticipa riesgos. El cuestionario toma entre 15 y 30 minutos para ser completado. Si tiene cualquier pregunta acerca de este cuestionario, puede contactar al investigador: Alan W. Hodges PO Box 10240 Gainesville, FL 32611 tel. 352-392-1881 x312 Email AWHodges@ufl.edu a nuestro patrocinador: USDA-ARS Invasive Plant Research Laboratory 3205 College Ave. Ft Lauderdale, FL 33314 tel. 954-475-0541, fax 954-476-9169 Email csilvers@saa.ars.usda.gov o visite nuestra pagina Web: http://tame.ifas.ufl.edu/ Para preguntas acerca de sus der echos como participante en este proyecto de investigacin, por favor contacte a la Universidad de la Florida en: University of Florida Institutional Review Board PO Box 112250, Gainesville, FL 32611 telephone 352-392-0433. Gracias por su valiosa participacin! Porfavor pase a la siguiente pagina

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101 English Version 1. Are you aware that some plants and trees are not native to this State? Please check Yes No 2. Are you aware that some non-native plan ts can harm local native plant species by overcrowding them or by altering natural areas? Yes No 3. Can you recognize the plant Melaleuca also known as Paper Bark or Punk Tree? Yes No 4. Are you aware that Melaleuca is not native to Florida? Yes No 5. Do you currently have any Melaleuca on your property? Yes No 6. If Yes, please estimate how much Melaleuca is on your property. Check response that applies : One Tree Two to Five Trees Six to 20 Trees One-Quarter Acre One-Half Acre One to Four Acres Five or More Acres Please turn the page

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102 Versin en Espaol 1 Esta usted al tanto de que algunas plantas y rboles existentes en la Florida no son nativas de este estado? Marque con una x S No 2. Esta usted al tanto de que algunas de esta s plantas no nativas pueden ser dainas para especies de plantas que s s on nativas? Por ejemplo, quitndol es su espacio o alterando su ecosistema natural. S No 3. Es usted capaz de reconocer la planta Melaleuca conocida tambin como rbol de Corteza de Papel? S No 4. Sabia usted que la Melaleuca es una especie no nativa de la Florida? S No 5. Existe o tiene en su propiedad un rbol de Melaleuca ? S No 6. Si su respuesta es si, puede darnos un estimado de cuanta Melaleuca hay en su propiedad. Un rbol Dos o Cinco rboles Seis a 20 rboles de acre (1000m2) Medio acre (2000m2) Uno a cuatro acres Cinco o ms acres (2 Has. o ms) Porfavor pase a la siguiente pagina

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103 English Version 7. If you have Melaleuca on your property, pl ease indicate which of the following methods you are currently using to contro l Melaleuca, and any that you would be interested to learn more a bout. Check any that apply. Method Currently Using Interested To Learn More About Mechanical only (felling, mowing, tilling, pulling, grubbing, without herbicides) Chemical (leaf application of herbicides) Girdling of stems followed by herbicides (Hack & Squirt) Stump treatment (felling followed by herbicides on cut stump) Biological control with beneficial insects Biological control combined with at least one other method Other methods (Specify): _________________________________ Check here if you have not used any control measures for Melaleuca 8. Barriers to Controlling Melaleuca Please indicate any reasons that may limit your ability to control Melaleuca Check any that apply Do not have Melaleuca on my property Melaleuca is not a problem for me DonÂ’t care about Melaleuca Infestations are too small Infestations are too large Controls will not work Do not know how to use controls Do not have time to use controls Controls will harm other plants Afraid of/dislike using chemicals Infested areas are inaccessible Do not have the necessary equipment for controls Environmental regulations prev ent me from using controls There are no cost sharing programs for controls Controls are too expensive Other reason; Specify: _________________________________ Please turn the page

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104 Versin en Espaol 7. Si es que tiene usted Melaleuca en su propiedad, por favor indique cual de los siguientes mtodos utiliza usted actualmente para controlar la Melaleuca y si hay alguno del cual usted deseara conocer ms. Marque todas las que aplican. Mtodo Usado actualmente Deseara conocer mas Solamente mecnico (tala, corte, labrado, arrancado a mano, escarbando, SIN herbicidas) Qumico (aplicacin de herbicidas directamente a la hoja) Corte y aplicacin en chorro a la zona de corte (Hack & Squirt) Tratamiento al tocn (tala seguida de aplicacin al tocn restante) Control biolgico con insectos benficos Control biolgico combinado con al menos un otro mtodo Otros mtodos(Especifique): _________________________________ Marque aqu si ningn mtodo es usado para controlar la Melaleuca 8. Impedimentos para controlar la Melaleuca Por favor indique cualquier motivo que le detenga de controlar la Melaleuca Marque cualquiera que se aplique a usted. No tengo Melaleuca en mi propiedad La Melaleuca no representa un problema para m Me es indiferente Las infestaciones son demasiado pequeas Las infestaciones son demasiado grandes Nada parece funcionar No s utilizar ningn mtodo de control No tengo tiempo para hacer cualquier tipo de control Los controles afectaran otras plantas Evito/me asusta el uso de qumicos Las reas infestadas son inaccesibles No poseo el equipo adecuado Las regulaciones ambientales no me lo permiten No existen programas para comp artir los costos de control Los controles son demasiado costosos Otros motivos; Especifique: __________________________ Porfavor pase a la siguiente pagina

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105 English Version 9. Information Media for Melaleuca Control. From what types of media have you received information about control of Melaleuca ? Check all that apply. Have Received Information Information Media Pamphlets or bulletins Video cassettes or CDs Area demonstration plots Computer software decision aids Website / Internet E-Mail newsletters or direct notifications Local and national news Newspapers Public television Other information media; Specify_____________________________________ 10. Information Sources for Melaleuca Control. From what sources have you received information about control of Melaleuca ? Check all that apply Have Received Information Information Source State and federal agencies Professional organizations Observation of other land managers UF/IFAS extension information Recommendations by landscape professionals TAME Melaleuca project Advice from other land managers Other information source(s); Specify: ____________________________________ Please turn the page

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106 Versin en Espaol 9. Medios de informacin para el control de la Melaleuca A travs de que medios de comunicacin ha recibido informacin acerca del control de la Melaleuca ? Marque todas las que se apliquen He recibido informacin Medio de comunicacin Panfletos o boletines Video cassettes o CDs reas de demostracin Paquetes de computo (software) para la ayuda de toma de decisiones El Internet y/o paginas Web E-mail (notificaciones directas o hojas informativas) Noticias locales o nacionales El diario (peridicos) Televisin publica Otros medios de comunicacin; Especifique: _____________________________________ 10. Fuentes de informacin para el control de la Melaleuca De cuales fuentes ha recibido usted informacin acerca del control de la Melaleuca ? Marque todas las que se apliquen He recibido informacin Fuente Agencias federales y del estado Organizaciones profesionales Observando el manejo de otros terratenientes Informacin del servicio de extensin UF/IFAS Recomendaciones hechas por profesionales en diseo y mantenimiento de areas verdes Proyecto TAME para la Melaleuca Consejos de otros terratenientes Otra(s) fuentes de informacin; Especifique: ____________________________________ Porfavor pase a la siguiente pagina

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107 English Version 11. Expenses for Melaleuca Control Estimate how much you sp ent specifically for the control of Melaleuca on your property since 1990 or since owning your property, including any costs for labor, contract se rvices, equipment, herbicides, etc. Please check appropriate range $0 to $49 $50 to $99 $100 to $249 $250 to $500 Over $500 If over $500, please estimate amount: $________ 12. Do you feel that Melaleuca has negatively affected th e value of your property? Please check Yes No If Yes, by what percen t has the value changed? _________% 13. What would you be willing to pay to remove/eradicate Melaleuca on your property? Please check appropriate range. $0-$49 $50 to $99 $100 to $249 $250 to $500 Over $500 If over $500, please estimate amount: $ ________ 14. Approximately how many days a year do you engage in the following outdoor recreational activities? Please enter number for each as appropriate Activity Number of Days Per Year Freshwater fishin g Hunting ______ Wildlife observation/photography ______ Boating/ATVÂ’s ______ Camping/Hiking ______ Other (specify) _____________________ ______ 15. Do you feel that Melaleuca has in any way affected your enjoyment of these outdoor recreationa l activities? Please check Yes No If Yes, has this affected you negatively or positively? Please check Positively Negatively Please turn the page

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108 Versin en Espaol 11. Costos del control para la Melaleuca Estime cuanto ha gastado especficamente para el control de la Melaleuca en su propiedad desde 1990 o desde que compro su propiedad, incluyendo costos de mano de obra, servicios contratados, equipo, herbicidas, etc. Por favor marque el rango apropiado. $0 to $49 $50 to $99 $100 to $249 $250 to $500 Arriba de $500 Si es mas de $500, por favor estime el monto: $________ 12. Siente usted que la Melaleuca ha afectado de una manera negativa al valor de su propiedad? Por favor marque S No Si su respuesta es s, cuanto a cam biado su valor en porcentaje? _________% 13. Cunto estara usted dispuesto a pagar para remover/erradicar la Melaleuca de su propiedad? Por favor marque el rango apropiado $0-$49 $50 to $99 $100 to $249 $250 to $500 Arriba de $500 Si es mas de $500, por favor estime el monto: $ ________ 14. Aproximadamente, cuantos das dedica uste d al ao para actividades recreacionales a campo abierto? Por favor ponga l numero apropiado para cada una de las actividades. Actividad Numero de das al ao Pesca en a g ua dulce ______ Cacera ______ Fotografa/observacin de la naturaleza ______ Pasear en barca/ATVÂ’s Caminatas y/o camping ______ Otras (especifique) ____________________ ______ 15 Siente usted que la Melaleuca ha afectado en alguna manera su disfrute de estas actividades a campo abierto? Por favor marque. S No Si su respuesta es si, las ha afect ado negativamente o positivamente. Por favor marque Positivamente Negativamente Porfavor pase a la siguiente pagina

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109 English Version 16. What would you be willing to pay per visit to reduce Melaleuca in the areas where you engage in outdoor recreational ac tivities? Assume these monies will support successful management. Please check $0 greater than $0 but less than $1 $1 $4 $5 $9 $10 $15 $16 $25 More than $25 If more than $25, please estimate amount: $__________ 17. In what zip code is your property located________________? 18. How long have you lived at your current residence? Please check less than a year one to five years five or more years 19. Do you own or lease the property where you reside? own lease 20. What is your gender: male female 21. In what year were you born? 19_______ 22. What is the highest level of fo rmal schooling you have completed? Less than high school diploma High school diploma or equivalent Some college or AA degree Technical/Trade School Bachelors degree Graduate/Professional degree Please turn the page

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110 Versin en Espaol 16. Cunto estara dispuesto a pagar por visita para reducir la Melaleuca en las reas donde usted suele realizar su s actividades recre acionales a campo abierto? Asuma que este dinero ser utilizado eficie ntemente para la reduccin de la Melaleuca Por favor marque. $0 mas de $0 pero menos de $1 $1 $4 $5 $9 $10 $15 $16 $25 mas de $25 Si es mas de $25, por favor estime cuanto: $__________ 17. Indique en que zip code se en cuentra ubicada su propiedad _________? 18. Cunto tiempo lleva usted viviendo en su residencia actual? Por favor marque. menos de un ao de uno a cinco aos cinco o ms aos 19. Es usted dueo o re nta su residencia? dueo rento 20. Indique su sexo: masculino femenino 21. Indique su ao de nacimiento 19_______ 22. Cul es el nivel mas alto de educacin formal que usted a completado? Menos que educacin secundaria (high school) Educacin secundaria completada o equivalente Algunos aos de universidad (AA degree) Titulo tcnico / licenciatura Titulo universitario / ingeniera (B.S. degree) Maestra / Doctorado Porfavor pase a la siguiente pagina

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111 English Version 23. Do you or anyone in your household own 25 or more acres of agricultural, forestry, or natural land in Florida? Yes No 24. Did you vote in a state or local election in the past 3 years? Yes No 25. Including yourself, how many pe ople live in your household?_______ 26. What was your total household income (before taxes) for last year (2003)? Less than $10,000 $10,000-$19,999 $20,000-$29,999 $30,000-$39,999 $40,000-$49,999 $50,000-$59,999 $60,000-$79,999 $80,000-$99,999 $100,000 or more Comments. Please offer any addition al thoughts or comments you may have regarding invasive plant management. Feel free to address any issues not covered in this questionnaire. Date survey completed: _____________ Check here if you wish to re ceive a copy of the study results. Name and Mailing Address: ________________________________ ________________________________ ________________________________ Please return this questionnaire in the envelope provided. Thank you again for your participation!

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112 Versin en Espaol 23. Usted o algn miembro de su familia poseen 25 o ms acres (10 Hectreas) de tierra en la Florida que pudiera ser utilizada para ag ricultura, silvicultura (forestal), o como reserva natural? S No 24. Vot en cualquiera de las elecciones lo cales o estatales de los ltimos 3 aos? S No 25. Incluyndose usted mismo, cuantas personas viven en su hogar? _______ 26. Cul es el monto total (incluyendo todos los miembros de su hogar) de ingresos (antes de impuestos) que percibi su hogar en el ao pasado (2003)? Menos de $10,000 $10,000-$19,999 $20,000-$29,999 $30,000-$39,999 $40,000-$49,999 $50,000-$59,999 $60,000-$79,999 $80,000-$99,999 $100,000 o ms Comentarios. Por favor dganos cualquier comentario o pensamiento adicional que pueda usted tener con respecto al manejo de pl antas invasivas. Sientase en la libertad de discutir cualquier tema incl uyendo cualquiera que no haya sido parte de este cuestionario. Fecha en que se completo el cuestionario: _____________ Marque aqu si desea recibir una copia de los re sultados de este estudio Nombre y Direccin pa ra el correo: _____________________________ _______________________________ _______________________________ Por favor enve este cuestionario por correo usando el sobre provisto. De nuevo le agradecemos por su valiosa participacin

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113 LIST OF REFERENCES Arrow, K. 1963. Social Change and Individual Values 2nd Edition. New York, NY: Wiley. Balciunas, J.K., and T.D. Cent er. 1991. “Biological contro l of Melaleuca quinquenervia: prospects and conflicts.” In: T.D. Center R.F. Doren, R.L. Hofstetter, R.L. Myers and L.D. Whiteaker (eds.). Proceedings of the Symposium on Exotic Pest Plants National Park Service, Denver, CO. NPS/NREVER/NRTR-91/06. 1-22. Benson, L.E. 1946. “Mail Surveys Can Be Valuable.” The Public Opinion Quarterly 10(2): 234-241. Blum, J.D., A. Damsgaard, and P.R. Sullivan. 1980. “Cost-Benefit Analysis.” Proceedings of the Academy of Political Science 33(4): 137-147. Bureau of Economic and Busine ss Research (BEBR). 2004. Florida Statistical Abstract Warrington College of Business, Universi ty of Florida. Gainesville, FL. Bureau of Invasive Plant Management (BIP M). 2003. “Upland Invasive Exotic Plant Management Program Report”. [Online]. Available at: http://www.dep.state.f l.us/lands/invaspec/2ndle vpgs/pdfs/Uplands%2020022003.pdf Accessed June 2004. Campbell, H., and R. Brown. 2003. Benefit Cost Analysis: Financial and Economic Appraisals Using Spreadsheets Cambridge, UK: Cambridge University Press. Carson, R. T., J.L. Wright, N. Cars on, A. Alberini, and N. Flores. 1994. A Bibliography of Contingent Valuation Studies and Papers La Jolla, CA: Natural Resource Damage Assessment, Inc. Cohn, E. 2003. “Benefit Cost Analysis: A Pedagogical Note.” Public Finance Review 31(5):534-549. Comprehensive Everglades Restoration Plan (CERP). 2004. “Central and Southern Florida Project. Comprehensive Ever glades Restoration Plan. Project Management Plan: Melaleuca Eradication and Other Exotic Plants.” [Online]. Available at: http://www.evergladesplan.org/pm/pmp/pmp_docs/pmp_95_melaleuca/092704_pm p_95_main_body.pdf Accessed June 2005.

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114 Costanza, R., R. d’Arge, R. de Groots, S. Farber, M. Grasso, B. Hannon, K. Limburg, S. Naeem, R.V. O’Neill, J. Paruelo, G.G. Ra skin, P. Sutton, and M. van den Belt. 1997. “The Value of the World’s Ecosystem Services and Natural Capital.” Nature 387: 253-260. Dardis, R., S. Aaronson, and Y. Lin. November 1978. “Cost-Benefit Analysis of Flammability Standards.” American Journal of Agricultural Economics 60(4): 695-700. Diamond, C., D. Davis and D.C. Schmitz. 1991. “Economic Impact Statement: The Addition of Melaleuca quinquenervia to the Florida Prohibite d Aquatic Plant List.” In: T.D. Center, R.F. Doren, R.L. Hofstetter, R.L. Meyers, and L.D. Whiteaker (eds.). Proceedings of the Sympos ium on Exotic Pest Plants National Park Service, Denver, CO. NPS/ NREVER/NRTR-91/06. 87-110 Dillman, D.A. 1978. Mail and Telephone Surveys: The Total Design Method New York, NY: Wiley and Sons. Dillman, D.A. 1991. “The Design and Administration of Mail Surveys.” Annual Review of Sociology 17: 225-249. Florida Natural Areas Inventory (FNAI). 2005. “Florida’s Conservation Lands Interactive Map.” Florida State Univ ersity. [Online]. Available at: http://data.labins.org/imf2/FREAC/FNAI.jsp ?. Accessed February 2006. Florida Statute 369.22, 251-.252. 2004. “T itle XXVIII-Natural Resources; Conservation, Reclamation, and Use.” State of Florida. [Online]. Available at: http://www.flsenate.gov/statutes/ Accessed June 2005. Flowers, J.D. II. 1991. “Subtropical Fire S uppression in Melaleuca qu inquenervia.” In: T.D. Center, R.F. Doren, R.L. Hofstetter, R.L. Myers and L.D. Whiteaker (eds.). Proceedings of the Symposium on Exotic Pest Plants National Park Service, Denver, CO. NPS/NREVER/NRTR-91/06. 151-158. Gittinger, J.P. 1982. Economic Analysis of Agricultural Projects Published for: The Economic Development Institute of the World Bank. Baltimore, MD: The Johns Hopkins University Press. Hanemann, M.W. 1994. “Valuing the Enviro nment Through Contingent Valuation.” Journal of Economic Perspectives 8(4):19-43. Hofstetter, R.H. 1991. “The Current Status of Melaleuca quinquenervia in Southern Florida.” In: T.D. Center, R.F. Dore n, R.L. Hofstetter, R.L. Myers and L.D. Whiteaker (eds.). Proceedings of the Sympos ium on Exotic Pest Plants National Park Service, Denver, CO. NPS/NREVER/NRTR-91/06. 159-176. Haveman, R.H. 1976. “Benefit-Cost Anal ysis and Family Planning Programs.” Population and Development Review 2(1): 37-64.

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115 Kahneman, D and J. Knetsch. 1992. “Valuing Public Goods: The Purchase of Moral Satisfaction.” Journal of Environmental Economics and Management 22:57-70. Kramer, R.C. and J.D. Schaffer. 1954. “The Case for the Mail Survey.” Journal of Farm Economics 36(4): 575-589. Laroche, F.B. and A.P. Ferriter. 1992. “The Rate of Expansion of Melaleuca in South Florida.” Journal of Aquatic Plant Management 30:62-65. Laroche, F.B. and J. McKim. 2004. “C ost Comparison of Melaleuca Treatment Methods.” South Florida Water Management District. [Online]. Available at: http://www.sfwmd.gov/org/clm/lsd/mitig ation/cell_17_18/cost_comparison_of_me laleuca.html Accessed February 2005. Mitchell, R.C. and R.T. Carson. 1989. Using Surveys to Value Public Goods: The Contingent Valuation Method. Resources for the Future. Washington, D.C.: The Johns Hopkins University Press. Money Generation Model 2 (MGM2). 2003. “M ethods.” Michigan State University. [Online]. Available at: http://www.prr.msu.edu/yayen/NPS/Methods.htm Accessed November 2005. Navrud, S. 1992. Pricing the European Environment New York, NY: Oxford University Press. Pearce, D.W. 1983. Cost-Benefit Analysis New York, NY: St. Martin’s Press. Pratt, P.D. and A.P. Ferriter. 2001. “P lan of Work for The Areawide Management Evaluation of Melaleuca quinquenervia (TAME Melaleuca).” United States Department of Agriculture and the Sout h Florida Water Management District. Portney, P.R. 1994. “The Contingent Va luation Debate: Why Economists Should Care.” Journal of Economic Perspectives 8:3-17. Prest, A.R. and R.Turvey. 1965. “Cost-benefit Analysis: A survey.” The Economic Journal 75(300):683-735. Rayamajhi, M.B., T.K. Van, T.D. Center, J.A. Goolsby, P.D. Pratt and A. Racelis. 2002. “Biological Attributes of the Canopy-H eld Melaleuca quinquenervia Seeds in Australia and Florida.” Journal of Aquatic Plant Management 40:87-91. Sassone, P.G. and W.A.Schaffer. 1978. Cost-Benefit Analysis. A Handbook New York, NY: Academic Press, Inc. Schelling, T. 1968. “The Life You Save May Be Your Own.” In: S. Chase (ed.). Problems in Public Expenditure Analysis. Washington, D.C.: Brookings Institution. 143-144.

PAGE 129

116 Schmitz, D.C. and R.H. Hofstetter. 1999. “Environmental, Economic and Human Impacts.” In: F. Laroche (ed.). Melaleuca Management Plan, Ten Years of Successful Melaleuca Manage ment in Florida 1988-1998 Florida Exotic Pest Plant Council. 17-21. [Online]. Available at: http://www.fleppc.org/Manage_Plans/mplan.pdf Accessed November 2005. Serbesoff-King, K. 2003. “Melaleuca in Fl orida: A Literature Review on the Taxonomy, Distribution, Biology, Ecology, Economic Importance and Control Measures.” Journal of Aquatic Plant Management 41:98-112. Stober, W.J. and L.H. Falk. 1967. “A Benef it-Cost Analysis of Local Water Supply.” Land Economics 43(3): 328-335. Stocker, R.K. and D.R. Sanders, Sr. 1981. “Chemical Control of Melaleuca quinquenervia.” In: R.K. Geiger (ed.). Proceedings of the Melaleuca Symposium Florida Department of Agriculture and C onsumer Services, Division of Forestry: Tallahassee, FL. 129-134. United States Department of Agriculture-Nati onal Agricultural Statistics Service (USDANASS). 2002. “2002 Census of Agriculture.” [Online]. Available at: http://www.nass.usda.gov/census/census02/volume1/fl/index2.htm Accessed February 2006. United States Department of Commerce-Bur eau of Economic Analysis. 2006. “Gross Domestic Product: Implicit Price Defl ator.” [Online]. Available at: http://research.stlouisfed.or g/fred2/data/GDPDEF.txt Accessed February 2006. Whittington, D. and W.N. Grubb. 1984. “Economic Analysis in Regulatory Decisions: The Implications of Executive Order 12291.” Science, Technology, and Human Values 9:63-71. Woodall, S.L. 1981. “Site Requirements for Melaleuca Seedling Establishment.” In: R.K. Geiger (ed.). Procedings of the Melaleuca Symposium Florida Department of Agriculture and Consumer Services, Di vision of Forestry. Tallahassee, FL. 915. Zansler, M.L. 2004. “The Economic Impacts to an Industry Associated with an Invasive Species: The Case of Citrus Canker in Flor ida.” Ph.D. Dissertat ion. University of Florida: Gainesville, FL. Zerbe, R.O. and D. D. Dively. 1994. Benefit Cost Analysis in Theory and Practice New York, NY: HarperCollins.

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117 BIOGRAPHICAL SKETCH Katherine Carter-Finn is a native of Sebring, Florida. After graduating with honors from Sebring High School in 1999 she receiv ed her A.A. degree from South Florida Community College in Avon Park, Florida, in 2000. Katherine graduated with honors and received her B.S. in food and resource ec onomics from the University of Florida in May 2003. She began the M.S. program in food and resource economics in August 2003. She plans to attend law school at the Univer sity of Florida after completing her M.S. degree requirements.