• TABLE OF CONTENTS
HIDE
 Historic note
 Main














Group Title: Water Quality Initiative Series circular - UF Soil Science Dept. ; no. 1004
Title: Spinach
CITATION PAGE IMAGE ZOOMABLE
Full Citation
STANDARD VIEW MARC VIEW
Permanent Link: http://ufdc.ufl.edu/UF00067192/00001
 Material Information
Title: Spinach managing pesticides for crop production and water quality protection : a supplement to the IFAS pest control guides
Series Title: Water quality initiative series Soil Science Dept
Alternate Title: Managing pesticides for crop production and water quality protection
IFAS pest control guides
Physical Description: 10 p. : ; 28 cm.
Language: English
Creator: Buttler, T. M
University of Florida -- Soil Science Dept
Publisher: Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida
Place of Publication: Gainesville Fla
Publication Date: 1991
 Subjects
Subject: Spinach -- Diseases and pests -- Control -- Environmental aspects -- Florida   ( lcsh )
Pesticides -- Environmental aspects -- Florida   ( lcsh )
Soil surveys -- Florida   ( lcsh )
Genre: government publication (state, provincial, terriorial, dependent)   ( marcgt )
non-fiction   ( marcgt )
 Notes
Statement of Responsibility: T.M. Buttler ... et al..
General Note: Cover title.
General Note: "May 1991."
Funding: Circular (Florida Cooperative Extension Service) ;
 Record Information
Bibliographic ID: UF00067192
Volume ID: VID00001
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.
Resource Identifier: oclc - 25052770

Table of Contents
    Historic note
        Historic note
    Main
        Page 1
        Page 2
        Page 3
        Page 4
        Page 5
        Page 6
        Page 7
        Page 8
        Page 9
        Page 10
        Page 11
        Page 12
Full Text





HISTORIC NOTE


The publications in this collection do
not reflect current scientific knowledge
or recommendations. These texts
represent the historic publishing
record of the Institute for Food and
Agricultural Sciences and should be
used only to trace the historic work of
the Institute and its staff. Current IFAS
research may be found on the
Electronic Data Information Source
(EDIS)

site maintained by the Florida
Cooperative Extension Service.






Copyright 2005, Board of Trustees, University
of Florida








S Soil Science Department
Water Quality Initiative Series


Circular 1004
May 1991


SPINACH


MANAGING PESTICIDES FOR CROP PRODUCTION

AND WATER QUALITY PROTECTION

A Supplement to the IFAS Pest Control Guides


T. M. BUTLER
and
A. G. HORNSBY
Soil Science Department

W. M. STALL
Vegetable Crops Department

F. A. JOHNSON
Entomology and Nematology Department

J. W. NOLING
CREC, Lake Alfred, FL

T. A. KUCHAREK
Plant Pathology Department
Institute of Food and Agricultural Sciences
University of Florida
Gainesville, FL 32611




Florida Cooperative Extension Service
Institute of Food and Agricultural Sciences
University of Florida, Gainesville
John T. Woeste, Dean for Extension









WATER QUALITY CONSIDERATIONS IN
SPINACH PRODUCTION

Concern about the harmful effects of pesticides on
surface water and groundwater quality should
motivate spinach growers to select pesticides with
the least potential to cause water quality problems.
Many spinach growers live in rural areas near where
they and other growers raise spinach, therefore,
their personal water supply is susceptible to
contamination. Unfortunately, information that
allows growers to select pesticides less likely to
affect water quality has not previously been readily
available.

Our purpose is to provide information that can help
growers select pesticides that will have a minimum
adverse impact on water quality. The procedure
considers the soil properties of the application site,
the mobility of pesticides in these soils, and the
toxicity of the pesticides in water to humans and
aquatic species. A proper selection will decrease
chances of adversely affecting surface water and
groundwater quality. Certain combinations of soil
and pesticide properties (along with weather
conditions) can pose a significant potential hazard
to water quality. Our goal is to identify and avoid
these circumstances. Information contained in this
report can help spinach growers make better
decisions about the pesticides that they use. This
document in no way endorses any particular pest
control product. All products must be used in
accordance with the label.


MATERIALS NEEDED TO USE THIS
PROCEDURE

To effectively use this procedure you will need the
following source materials:

1. A copy of the current IFAS Pest Control Guides
or other appropriate information sources that
identify pesticides that control specific pests.

2. A copy of your county soil survey report to
identify the soil types found in your fields.

3. A copy of the Soil Science Fact Sheet entitled
"[Name of your county]:Soil Ratings for Selecting
Pesticides" for your county, available from your
county Cooperative Extension Office. The basis of
these ratings are given in the IFAS Extension


Circular 959 entitled "Soil Ratings for Selecting
Pesticides for Water Quality Goals," which is also
available from your county Cooperative Extension
Office.

Note: If your county has not yet been mapped by
the Soil Conservation Service, you will need to
contact the local SCS office for a site evaluation and
determination of soil types and ratings for leaching
and runoff of pesticides.


IMPORTANT FACTORS
PESTICIDE SELECTION


THAT AFFECT


How pesticides behave in the soil is determined by
many factors including properties of the pesticides
and of the soil at the application site. Some of the
factors that should be considered when selecting
pesticides with minimal potential for water quality
impacts are:

Pesticide properties 1) The organic carbon
adsorption coefficient, KI describes the relative
affinity or attraction of the pesticide to soil
materials and therefore its mobility in the soil. 2)
The biological degradation half-life, T,, is a
measure of persistence of the pesticide in soil. 3)
The lifetime health advisory level or equivalent,
HALEQ, is a measure of health risk to humans of
pesticide contaminated drinking water. 4) Aquatic
toxicity, LC, is a measure of the ability of the
pesticide to cause 50% mortality in aquatic test
species.

Soil properties 1) Hydraulic permeability is a
measure of the soils ability to allow water to
percolate through it. 2) Organic matter is
important for providing binding sites for pesticides,
thus reducing their mobility and increasing their
opportunity to be degraded by soil microorganisms.
3) Slope affects the potential for water to run off
the land surface.

Management practices 1) Pesticide application
frequencies and rates determine the total amount
applied. Lower frequencies and rates reduce the
potential for contamination. 2) Application
methods affect the amount of pesticide subject to
transport by water. For example, if applied directly
to the soil, there is a greater probability that more
of the product will be available for leaching or
runoff than if applied to the foliage. If the product









is incorporated into the soil, leaching may be the
most important loss pathway. Pesticides applied to
the foliage may be lost to the atmosphere,
decomposed by sunlight, or absorbed by the foliage,
thereby reducing the amount available for wash-off
and transport to water bodies. Irrigation practices
can also determine the loss pathways of pesticides.
Pesticides often move with water, so the less excess
water that is applied the less potential there is for
a pesticide to move past the crop root zone or to
run off in surface water. Rainfall or overhead
irrigation can wash off significant quantities of
pesticides from foliage immediately after
application.


INDICES USED TO SELECT PESTICIDES

Table 1 contains two important indices, the
pesticide leaching potential (RLPI) and the
pesticide runoff potential (RRPI). Both indices are
relative. For a given soil, these indices rank the
pesticides by their potential to move from the
application site by the indicated pathway (leaching
or runoff). The indices are based on the organic
carbon sorption coefficient and degradation half-life
values of each pesticide. Values for these
parameters have been taken from scientific
literature, technical manuals, and company product
literature.

The Relative Leaching Potential Index (RLPI)
defines the relative attenuation (reduction in mass
as it moves through the soil) of each pesticide in
soil, and therefore its potential to leach to
groundwater. Pesticides that are very mobile, for
example, those that have Kc values less than 100 in
sandy soils, or 50 or less in fine-textured soils
should be used with caution. There is some
uncertainty in the data used to calculate this index.
However, since the values are relative they can still
be used. It is important to realize that the smaller
the RLPI value of a pesticide the greater is its
potential to leach.


The Relative Runoff Potential Index (RRPI)
defines the relative immobility and availability of
each pesticide in soil, and therefore its potential to
remain near the soil surface and be subject to loss
in the aqueous phase or sediment phase of runoff.
There is some uncertainty in the data used to
calculate this index. However, since the values are


relative they can still be used. The smaller the
RRPI value of a pesticide the greater is its potential
to be lost in runoff.

Table 1 also contains information on the toxicity of
pesticides to humans and aquatic species. This
information can be used as a secondary
consideration in the pesticide selection procedure.


The Lifetime Health Advisory Level or Equivalent
(HALEQ) provides a measure of pesticide toxicity
to humans. The lifetime health advisory level as
defined by the USEPA is the concentration of a
chemical in drinking water that is not expected to
cause any adverse health effects over a lifetime of
exposure (70 years), with a margin of safety. The
values in Table 1 are the USEPA lifetime health
advisory level, HAL, or an equivalent value,
HALEQ (denoted by a superscripted asterisk),
calculated using the same formula used by the
USEPA (HALEQ = RfD x 7000), where RfD is
the reference dose determined by the USEPA. For
non-carcinogenic pesticides the calculated HALEQ
should not differ by more than a factor of 10 from
the values forthcoming from the USEPA. The
HAL or HALEQ has units of micrograms per liter
(pg/l, or ppb). The smaller the value the greater is
the toxicity to humans.

The Aquatic Toxicity provides a measure of
pesticide toxicity to aquatic species. The values
given in Table 1 are the lethal concentrations at
which 50% of the test species die (LC, ). Unless
otherwise noted by a lower case letter following the
value, the test species was rainbow trout. The
smaller the value the greater is the toxicity to
aquatic species.

Data for K0, RLPI, RRPI, HALEQ, and aquatic
toxicity are given for the active ingredient (common
name) of a product. When using a product that is
a mixture of two or more active ingredients use the
RLPI, RRPI, HALEQ, and Aquatic Toxicity value
for the most restrictive active ingredient in the
mixture.

Important Note: The information presented in
Table 1 DOES NOT supersede or replace the
information on the pesticide container label or
product literature.









CRITERIA FOR MATCHING SOIL RATINGS WITH PESTICIDE INDICES


Pesticides with less potential to adversely affect water quality can be selected by matching the soil ratings and
pesticides using the following criteria:


PESTICIDE SELECTION CRITERIA


IF SOIL RATINGS
ARE:


THEN
SELECT PESTICIDE WITH:


RUNOFF


LOW

LOW

LOW


MEDIUM


MEDIUM


MEDIUM


HIGH


HIGH


HIGH


Larger RLPI value,

Larger RLPI value,

Larger RLPI and
RRPI values,

Larger RLPI and
RRPI values,

Larger RLPI and
RRPI values,

Larger RRPI value,


Larger RLPI and
RRPI values,

Larger RRPI and
RLPI values,

Larger RRPI value,


AND Larger HALEQ value.

AND Larger HALEQ value.

AND Larger HALEQ and
Aquatic Toxicity values.

AND Larger HALEQ and
Aquatic Toxicity values.

AND Larger HALEQ and
Aquatic Toxicity values.

AND Larger Aquatic Toxicity
value.

AND Larger HALEQ and
Aquatic Toxicity values.

AND Larger Aquatic Toxicity
and HALEQ values.

AND Larger Aquatic Toxicity
value.


PROCEDURE FOR SELECTING PESTICIDES
TO REDUCE ADVERSE WATER QUALITY
IMPACTS

A "Pesticide Selection Worksheet" is provided as a
convenient way to organize the information needed
to select pesticides to avoid water pollution by
pesticides in a particular production or management
unit. Instructions for using the worksheet are
outlined below. The function of the worksheet is to
match the soil leach and runoff ratings at the
application site with the pesticide RLPI (leaching)
and RRPI (runoff) indices and toxicity values given
in Table 1.


This will indicate the relative potential for pesticides
to leach or run off from a particular site and
consider the toxicity of the pesticides to humans or
aquatic life if the pesticides leach into groundwater
or if runoff enters surface impoundments or
streams. The last two columns are for recording the
spinach grower's choices and reasons for selecting
particular products.

Our intent is to provide a decision support tool for
the spinach grower. The grower is responsible for
making the final choice. The completed worksheet
can serve as a permanent record of the selection
process used and decision made by the grower.


LEACH

HIGH

MEDIUM


LOW


HIGH


MEDIUM


LOW


HIGH


MEDIUM


LOW









USING THE WORKSHEET


1. TARGET PEST: Correct identification of the
pests that need to be controlled is essential! Check
with knowledgeable experts and utilize competent
diagnostic laboratories so that a proper diagnosis
can be made. Misdiagnosis results in the wasteful
use of unnecessary pesticides and needless increases
in production costs. List confirmed pests in column
1 of the Pesticide Selection Worksheet.


2. RECOMMENDED PESTICIDES: Use the
current IFAS Pest Control Guides, or other
appropriate information sources to identify the
pesticides that control the pests of concern. List
these pesticides in column 2 of the Pesticide
Selection Worksheet.


3. PESTICIDE PROPERTIES: For each pesticide
listed in column 2 on the Pesticide Selection
Worksheet, copy the numeric value for KI, RLPI,
RRPI, HALEQ, and Aquatic Toxicity from Table 1
into columns 3, 4, 5, 6, and 7 of the Pesticide
Selection Worksheet.


4. SOIL PROPERTIES: Consult the County Soil
Survey Report soil map sheets to locate your
production fields and to identify the soils that occur
in these fields. Use the Soil Science Fact Sheet
entitled "[Your County]:Soil Ratings for Selecting
Pesticides" (available from your county Cooperative
Extension Office) to determine the leaching and
surface runoff rating of the soils in your fields. As
you determine the soil leach rating and the soil
runoff rating for each soil in each field, list the soil
name, soil leach rating, and soil runoff rating in
columns 8, 9, and 10, respectively, of the Pesticide
Selection Worksheet.


5. SELECTION OF PESTICIDES: Using infor-
mation that you have compiled on the Pesticide
Selection Worksheet, select appropriate pesticides
using the selection criteria on page 4 to match soil
and pesticide properties. The selection made can
be recorded in column 11 and notes relating to the
selection can be recorded in column 12.


Notes:
1. If the pesticide product selected is a formulated
mixture or a tank mix, each active ingredient must
be considered. The most restrictive pesticide in the
mixture will determine the choice. Trade names in
Table 1 followed by (M) are formulated mixtures.

2. Sometimes there may not be a clear choice from
among the alternative chemicals available to control
a particular pest. In these cases, first order
screening using the RLPI or RRPI only can suffice.

3. Depth to groundwater and local geohydrology
may influence your final selection. Shallow
groundwater is more vulnerable to contamination.
Deep water tables with intervening impermeable
geologic layers are much less vulnerable.

4. Distance to surface water bodies may also
influence your final selection. Surface waters
adjacent to or near the pesticide application site are
more vulnerable to contamination than those further
away. If surface runoff from the application site
usually infiltrates into the soil off site before
reaching a surface water body, then the HALEQ
should be considered as the secondary screening
index.














Sorption Relative Losses Toxicity
Application Type2 Coefficient3 Leaching Runoff HAL or HALEQ6 Aquatic LCo7
Trade Name1 Common Name Soil Foliar Koc (ml/g) RLPI4 RRPI5 (ppb) (ppm)


Herbicide

Antor diethatyl-ethyl x 1,400 E 467 24 nd 1.82
Roundup glyphosate x 24,000 E >2,000 1 700 8.3


Insecticide/Miticide

Ambush permethrin x 100,000 >2,000 1 400 0.0041
Cygon dimethoate x 20 29 29 1 6.2
Cythion malathion x 1,800 >2,000 556 200 0.2
Dazzel diazinon INC x 1,000 E 250 25 0.6 0.09
Di-Syston disulfoton INC x 600 E 200 56 0.3 1.85
Diazinon diazinon INC x 1,000 E 250 25 0.6 0.09
Dipel Bacillus thuringiensis x nd nd nd nd 95b
Dylox trichlorfon x 10 10 10 900 0.4
Guthion azinphos-methyl x 1,000 1,000 100 9 0.0043
Isotox lindane x 1,100 28 2 0.2 0.027
Javelin Bacillus thuringiensis x nd nd nd nd 95b
Lannate methomyl x 72 24 24 200 3.4
Marlate methoxychlor x 80,000 >2,000 1 400 0.062
Metaldehyde metaldehyde x 240 240 240 nd non toxic
Metasystox oxydemeton-methyl x 10 10 10 4 6.4
Meticide methyl-parathion x 5,100 E >2,000 39 2 3.7
Monitor methamidophos x 5 8 8 0.4 51
Niran parathion INC x 5,000 E >2,000 14 2 1.43
Noxfire rotenone x 772 nd nd 30 0.031
Nudrin methomyl x 72 24 24 200 3.4
Orthene acephate x 2 7 7 30 730
Pay Off flucythrinate x 100,000 E >2,000 1 100 0.0003
Phosdrin mevinphos x 44 147 147 2 0.0119
Pounce permethrin x 100,000 >2,000 1 400 0.0041
Pynamin allethrin x nd nd nd nd 30.1a
Safer Soap insecticidal soap x nd nd nd nd nd
Sevin carbaryl x 300 300 300 700 114

HAL or HALEQ6: Lifetime Health Advisory Level or Lifetime Health Advisory Level Equivalent.

Continued---


05/1/9


TABLE i. Spinach Pesticide Parameter Matrix for Selectins Pesticides to Minimize Yater Puality Problems.


19(10/50









TABLE 1. Spinach Pesticide Parameter Natrix---Continued:


Sorption Relative Losses Toxicity
Application Type2 Coefficient3 Leaching Runoff HAL or HALEQ6 Aquatic LC,
Trade Name' Common Name Soil Foliar Koc (mt/g) RLPI4 RRPI5 (ppb) (ppm)


Insecticide/Miticide

Spectracide diazinon x 1,000 E 250 25 0.6 0.09
Systox demeton x 460 153 72 0.3 0.69
Thiodan endosulfan x 12,400 >2,000 2 0.4 0.0014


Fungicide

Captan captain x 200 800 800 900 0.0732
Ridomil metalaxyl x 50 7 7 400 >100
Terractor PCNB x 5,000 E >2,000 10 20 Low toxicity
Thiram thiram x 670 447 100 40 0.13
Topsin M thiophanate-methyl x x 1,830 E 1,830 55 600 11d


Fumigants for Control of Soil Fungi and Nematodes

Telone II 1,3-dichloropropene INJ 32 32 32 0.2 5.5
Telone C-17(M) chloropicrin INJ 62 620 620 nd nd
Telone C-17(M) 1,3-dichloropropene INJ 32 32 32 0.2 5.5
Vapam metam-sodium INJ 10 E 14 14 nd 0.39b
Vorlex(M) 1,3-dichloropropene INJ 32 32 32 0.2 5.5
Vorlex(M) M.I.T. INJ 6 9 9 nd 0.37


Trade Name:
2Application Type:
3Sorption Coefficient:
4Relative Leaching Potential Index (RLPI):
5Relative Runoff Potential Index (RRPI):
6HAL or HALEQ:

Aquatic Toxicity LC0,:


(M) indicates that the product is a mixture of two or more active ingredients.
INC: incorporated INJ: injected x: applied to soil surface or foliage
E: estimated G: educated guess
Smaller number indicates greater leaching hazard.
Smaller number indicates greater runoff hazard.
Lifetime Health Advisory Level or Lifetime Health Advisory Level Equivalent.
*: Lifetime Health Advisory Equivalent
value is for rainbow trout 48 or 96 hr exposure time, unless otherwise specified


a=channet catfish


b=bluegiLL


d=gold fish


nd: no data available.








PESTICIDE SELECTION WORKSHEET


Landowner/Operator Name:


County:


:arm ID:


Field ID Sheet of


IFAS Relative Losses Toxicity Soil Soil
Target Pest Recommended K, Leaching Runoff Lifetime Aquatic Soil Leaching Runoff Selected Comments
Pesticides Value RLPI RRPI HALEQ* Toxicity Type Rating Rating Pesticide
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12)


If the K. value is 100 or Less or if the RLPI value is 10 or less and the soil leach rating is high, then
be used with extreme caution. Alternative pesticides and reduced rates should be considered if possible.
if possible.


the pesticide has a high potential for Leaching and should
Apply pesticide during periods with low potential for rainfall


late:


F


ua.


1 r


D


op:


.


D






PESTICIDE SELECTION WORKSHEET


County:


Landowner/Operator Name:

Crop:


Farm ID


Date:


field ID Sheet of


IFAS Relative Losses Toxicity Soil Soil
Target Pest Recommended Ko Leaching Runoff Lifetime Aquatic Soil Leaching Runoff Selected Comments
Pesticides Value RLPI RRPI HALEQ* Toxicity Type Rating Rating Pesticide
(1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12)


I .III


I 4. 4. I I I 4. I 4. I


If the Ko value is 100 or less or if the RLPI value is 10 or less and the soil Leach rating is high, then the pesticide has a high potential for leaching and should
be used with extreme caution. Alternative pesticides and reduced rates should be considered if possible. Apply pesticide during periods with low potential for rainfall
if possible.


~:F









Acknowledgements:


The development of this document was supported by the USDA/ES Water Quality Initiative Project
#89EWQI-1-9134 and the IFAS Center Natural Resources, University of Florida, Gainesville, FL.





















































































COOPERATIVE EXTENSION SERVICE, UNIVERSITY OF FLORIDA, INSTITUTE OF FOOD AND AGRICULTURAL SCIENCES, John T. Woeste,
Director, in cooperation with the United States Department of Agriculture, publishes this information to further the purpose of the May 8 and June
30,1914 Acts of Congress; and is authorized to provide research, educational information and other services only to individuals and institutions that
function without regard to race, color, sex, age, handicap or national origin. Single copies of extension publications (excluding 4-H and youth
publications) are available free to Florida residents from county extension offices. Information on bulk rates or copies for out-of-state purchasers
is availablefrom C.M. Hinton, Publications Distribution Center, IFAS Building 664, University of Florida, Gainesville, Florida 32611. Before publicizing
this publication, editors should contact this address to determine availability. Printed 11/91.




University of Florida Home Page
© 2004 - 2010 University of Florida George A. Smathers Libraries.
All rights reserved.

Acceptable Use, Copyright, and Disclaimer Statement
Last updated October 10, 2010 - - mvs