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Title: Vegetable production handbook for Florida
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Title: Vegetable production handbook for Florida
Physical Description: Serial
Language: English
Creator: IFAS Extension, University of Florida
Publisher: IFAS Extension, University of Florida
Place of Publication: Gainesville, Fla.
Publication Date: 2010
Copyright Date: 2010
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Bibliographic ID: UF00099159
Volume ID: VID00001
Source Institution: University of Florida
Holding Location: University of Florida
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Full Text





















H E iL7 c-x--a .*






UF UNIVERSITY of
UF FLORIDA
IFAS Extension
2010-2011


Florida ranks second among the states in fresh market
vegetable production on the basis of harvested acreage
(10.9 %), production (9.5 %) and value (14.9 %) of the
crops grown (Table 1.). In 2008, vegetables were har-
vested from 219,900 acres and had a farm value exceeding
1.88 billion dollars.

A more detailed analysis of the national importance of
Florida production of specific vegetables indicates that
Florida ranks first in fresh-market value of snap bean,
cucumber, squash, sweet corn, tomatoes and watermelons.
Florida ranks second in fresh market value of strawberry
and sweet pepper and third in cabbage.


More than 40 different crops are grown commercially
in Florida with 8 of these exceeding $100 million in value.
Harvest occurs in late fall, winter and spring when at times
the only available United States supply is from Florida.

On the basis of value, in 2008 tomato production
accounted for about 33.1 % of the state's total value.
Other major crops with a lesser proportion of the 2008
crop value were sweet pepper (14.2 %), strawberry (13.3
%), snap beans (9.1 %), sweet corn (8.3 %), watermelon
(7.5 %), potatoes (7.0 %), cucumber (6.7 %) and squash
(2.8 %).


Table 1. Leading fresh market vegetable producing states, 2008.

Harvested acreage Production Value
Rank State Percent of total State Percent of total State Percent of total
1 California 44.1 California 49.1 California 50.4
2 Florida 10.9 Florida 9.5 Florida 14.9
3 Arizona 6.8 Arizona 7.4 Arizona 7.0
4 Georgia 6.2 Georgia 4.9 Georgia 4.4
5 New York 3.8 New York 3.6 New York 3.9
Source: Vegetables, USDA Ag Statistics, 2007.


Page 1


Chapter 1.


Introduction

S.M. Olson







Page 2 is
missing from
the original
document





WU UNIVERSITY of
UFFLORIDA
IFAS Extension
2010-2011
Chapter 2. HS711

Soil and Fertilizer Management for Vegetable Production in Florida

E.H. Simonne and G.J. Hochmuth


BEST MANAGEMENT PRACTICES
With the passage of the Federal Clean Water Act
(FCWA) in 1972, states were required to assess the
impacts of non-point sources of pollution on surface and
ground waters, and establish programs to minimize them.
Section 303(d) of the FWCA also requires states to iden-
tify impaired water bodies and establish total maximum
daily loads (TMDLs) for pollutants entering these water
bodies. Water quality parameters targeted by the TMDLs
and involving vegetable production are concentrations
of nitrate, phosphate, and total dissolved solids in these
waters. A TMDL establishes the maximum amount of pol-
lutant a water body can receive and still keep its water
quality parameters consistent with its intended use (swim-
ming, fishing, or potable uses). The establishment of the
TMDLs is currently underway and they will be implement-
ed through a combination of regulatory, non-regulatory,
and incentive-based measures. Best Management Practices
(BMPs) are specific cultural practices aimed at reduc-
ing the load of a specific compound, while maintaining
or increasing economical yields. They are tools available
to vegetable growers to achieve the TMDLs. BMPs are
intended to be educational, economically sound, environ-
mentally effective, and based on science. It is important to
recognize that BMPs do not aim at becoming an obstacle
to vegetable production. Instead, they should be viewed as
a means to balance economical vegetable production with
environmental responsibility.

The BMPs that will apply to vegetable production in
Florida are described in the 'Agronomic and Vegetable
Crop Water Quality/Water Quantity BMP Manual for
Florida'. This manual was developed between 2000 and
2005 through a cooperative effort between state agen-
cies, water management districts and commodity groups,
and under the scientific leadership of the University of
Florida's Institute of Food and Agricultural Sciences (UF/
IFAS). The manual has undergone a thorough scientific
review in 2003 and was presented to stakeholders and state
commodity groups for feed back in 2004. The manual
was adopted by reference in 2006 and by rule in Florida
Statutes (5M-8 Florida Administrative Code) and may be
consulted on-line at http://www.floridaagwaterpolicy.com/
PDFs/BMPs/vegetable&agronomicCrops.pdf. BMPs are
1-to-3 page long chapters that include a picture, a working
definition of the topic, list specific things to do (BMPs) as


well as things to avoid (pitfalls), and present existing appli-
cable technical criteria together with additional references.

Vegetable growers may get one-on-one information on
1) the benefits for joining the BMP program, 2) how to
join it, 3) how to select the BMPs that apply to their opera-
tion and 4) record keeping requirements by getting in con-
tact with their county extension agent or their local imple-
mentation team (see the vegetable BMP website at www.
imok.ufl.edu/bmp/vegetable for more information).

The vegetable BMPs have adopted all current UF/IFAS
recommendations, including those for fertilizer and irriga-
tion management (see BMP no. 33 "Optimum Fertilizer
Management" on pg. 93 of BMP manual). Through the
implementation of a series of targeted cultural practices
(the BMPs), growers should be able to reconcile economi-
cal profitability and responsible use of water and fertilizer.
At the field level, adequate fertilizer rates should be used
together with irrigation scheduling techniques and crop
nutritional status monitoring tools (leaf analysis, petiole
sap testing). In the BMP manual, adequate fertilizer rates
may be achieved by combinations of UF/IFAS recom-
mended base rates and supplemental fertilizer applications.



SOILS
Vegetables are grown on more than 300,000 acres in vari-
ous soil types throughout the state. These soil types include
sandy soils, sandy loam soils, Histosols (organic muck), and
calcareous marl soils. Each soil group is described below.

Sands
Sandy soils make up the dominant soil type for vegetable
production in Florida (Fig. 2-1). Vegetables are produced on
sandy soils throughout the Florida peninsula and on sandy
soils and sandy loams in the panhandle. Sandy soils have
the advantage of ease of tillage and they can produce the
earliest vegetable crops for a particular region. Sandy soils
allow timely production operations such as planting and
harvesting. Sandy soils, however, have the disadvantage
that mobile nutrients such as nitrogen, potassium and even
phosphorus can be leached by heavy rain or over irrigation.
Therefore, sands must be managed carefully with regard to
fertility programs. Sands hold very little water; therefore,


Page 3


This document is HS711, Horticultural Sciences Dept., UF/IFAS, Fla. Coop. Ext. Serv., May 2010







Vegetable Production Handbook


Table 1. Fertilizer nutrients required by plants.

Nutrient Deficiency symptoms Occurrence


Nitrogen (N)


Phosphorus (P)


Potassium (K)


Boron (B)




Calcium (Ca)




Copper (Cu)

Iron (Fe)

Magnesium (Mg)


Manganese (Mn)

Molybdenum (Mo)


Zinc (Zn)

Sulfur (S)



Chlorine (CI)


Stems thin, erect, hard. Leaves small, yellow; on
some crops (tomatoes) undersides are reddish.
Lower leaves affected first.
Stems thin and shortened. Leaves develop purple
color. Older leaves affected first. Plants stunted
and maturity delayed.
Older leaves develop gray or tan areas on leaf
margins. Eventually a scorch appears on the
entire margin.
Growing tips die and leaves are distorted.
Specific diseases caused by boron deficiency
include brown curd and hollow stem of
cauliflower, cracked stem of celery, blackheart
of beet, and internal browning of turnip.
Growing-point growth restricted on shoots and
roots. Specific deficiencies include blossom-end
rot of tomato, pepper and watermelon, brownheart
of escarole, celery blackheart, and cauliflower or
cabbage tipburn.
Yellowing of young leaves, stunting of plants. Onion
bulbs are soft with thin, pale scales.
Distinct yellow or white areas between veins on
youngest leaves.
Initially older leaves show yellowing between
veins, followed by yellowing of young leaves.
Older leaves soon fall.
Yellow mottled areas between veins on youngest
leaves, not as intense as iron deficiency.
Pale, distorted, narrow leaves with some
interveinal yellowing of older leaves,
e.g. whiptail disease of cauliflower. Rare.
Small reddish spots on cotyledon leaves of beans;
light areas (white bud) of corn leaves.
General yellowing of younger leaves and
reduced growth.


Deficiencies very rare.


On sandy soils especially after heavy rain or after
overirrigation. Also on organic soils during cool
growing seasons.
On acidic soils or very basic soils.
Also when soils are cool and wet.

On sandy soils following leaching rains
or overirrigation.

On soils with pH above 6.8 or on sandy, leached
soils, or on crops with very high demand such
as cole crops.


On strongly acidic soils, or during severe droughts.




On organic soils or occasionally new mineral soils.

On soils with pH above 6.8.

On strongly acidic soils, or on leached sandy soils.


On soils with pH above 6.4.

On very acidic soils.


On wet, cold soils in early spring or where
excessive phosphorus is present.
On very sandy soils, low in organic matter,
especially following continued use of sulfur-free
fertilizers and especially in areas that receive little
atmospheric sulfur.
Usually only under laboratory conditions.


irrigation management is more critical compared to other
soil types used for vegetable production in Florida. Nearly
all vegetable crops produced in Florida can be successfully
grown on sandy soils. The major vegetable crops such as
tomatoes, peppers, potatoes, watermelons, strawberries,
and cabbage are grown commonly on sandy soils.

Histosols
Histosols are organic soils which occur in areas through-
out the peninsula, especially in southern and central Florida
(Fig. 2-2). Large organic deposits used for vegetable pro-
duction occur south of Lake Okeechobee. Smaller pockets
of "muck" occur throughout central and northern Florida.
Histosols consist largely of decomposing plant material and
are largely underlain by calcareous deposits. Muck soils
have large water and nutrient holding capacities and are
used to produce crops such as the leafy vegetables (leaf let-
tuce, and various greens), celery, sweet corn, and radishes.
With time, the organic matter decomposes and the muck


subsides. Thus, the pH in the muck can increase because
of proximity to the underlying calcareous material. Muck
subsidence causes problems for water and nutrient man-
agement. The increase in pH due to subsidence and also to
the practice of flooding the Histosols to reduce oxidation
can result in increased requirements of phosphorus and
micronutrients. These nutrients can be fixed by the high pH
of the soil. Nutrient management in these situations should
involve banding rather than increased rates of nutrients.

Calcareous Rock and Marl
The calcareous soils in southern Florida (Miami-
Dade County) consist of two phases, rockland and marl.
Rockland soils are calcium carbonate soils consisting
of particles that range from sand-like in size to pebble
and gravel (Fig. 2-3). The rockland soils are extremely
shallow, about 4 to 6 inches deep. The marl is the fine-
textured, clay-like phase of the calcium carbonate soils.
Tomatoes, beans, summer squash, okra, sweet corn, boni-


Page 4







Chapter 2: Soil and Fertilizer Management for Vegetable Production in Florida


Table 2. Mehlich-1 (double-acid) interpretations for vegetable crops in Florida.

Element Very low Low Medium High Very high
Parts per million soil
P <10 10-15 16-30 31-60 >60
K <20 20-35 36-60 61-125 >125
Mg1 <10 10-20 21-40 41-60 >60
Ca2 <100 100-200 201-300 301-400 >400
1 Up to 40 lbs/a may be needed when soil test results are medium or lower
2 Ca levels are typically adequate when > 300 ppm


Table 3. Interpretations of Mehlich-1 soil tests for micronutrients.

Soil pH (mineral soils only)
5.5 5.9 6.0 6.4 6.5 7.0

parts per million
Test level below which there may be a crop response to applied copper. 0.1 0.3 0.3 0.5 0.5
Test level above which copper toxicity may occur. 2.0 3.0 3.0 5.0 5.0
Test level below which there may be a crop response to applied manganese. 3.0 5.0 5.0 7.0 7.0 9.0
Test level below which there may be a crop response to applied zinc. 0.5 0.5 1.0 1.0 3.0
When soil tests are low or known deficiencies exists, apply per acre 5 lbs Mn, 2 lbs Zn, 4 lbs Fe, 3 lb Cu and 1.5 lbs B (higher rate needed
for cole crops).


ato, and strawberries can be produced in the winter months
on the rockland soils of Miami-Dade County. Potatoes,
malanga, snap beans and sweet corn are produced on
the marl. Both soils have extremely high pH, therefore,
nutrients such as phosphorus and micronutrients must be
banded to ensure availability.



SOIL TESTING

Plants require 16 elements for normal growth and
reproduction (Table 1). The crop nutrient requirement
(CNR) for a particular element is defined as the total
amount in lb/A of that element needed by the crop to pro-
duce economic optimum yield. This concept of economic
optimum yields is important for vegetables because a cer-
tain amount of nutrients might produce a moderate amount
of biomass, but produce negligible marketable product due
to small fruit size. Fruit size and quality must be consid-
ered in the CNR concept for vegetables.

The CNR can be satisfied from many sources, includ-
ing soil, water, air, organic matter, or fertilizer. For
example, the CNR of potassium (K) can be supplied from
K-containing minerals in the soil, from K retained by soil
organic matter, or from K fertilizers.

The CNR for a crop is determined from field experi-
ments that test the yield response to levels of added fertil-
izer. For example, a watermelon study involving K might


be conducted on a soil which tests very low in extractable
K. In this situation, the soil can be expected to contrib-
ute only a small amount of K for optimum watermelon
growth and yield, and K must be supplied largely from
fertilizer. The researcher plots the relationship between
crop yield and fertilizer rate. The CNR is equivalent to
the fertilizer rate above which no significant increases in
yield are expected. The CNR values derived from such
experiments take into account factors such as fertilizer
efficiencies of the soils. These efficiencies include fertil-
izer leaching or fertilizer nutrient fixing capability of the
soil. If data are available from several experiments, then
reliable estimates of CNR values can be made. Using the
CNR concept when developing a fertilizer program will
ensure optimum, economic yields while minimizing both
pollution from overfertilization and loss of yield due to
underfertilization.

The CNR values are those amounts of nutrients needed
to produce optimum, economic yields from a fertilization
standpoint. It is important to remember that these nutrient
amounts are supplied to the crop from both the soil and
the fertilizer. The amounts are applied as fertilizers only
when a properly calibrated soil test indicates very small
extractable amounts of these nutrients to be present in the
soil. Therefore, soil testing must be conducted to deter-
mine the exact contribution from the soil to the overall
CNR. Based on such tests, the amount of fertilizer that
is needed to supplement the nutrition component of the
native soil can be calculated (Tables 2 and 3).


Page 5







Vegetable Production Handbook


Table 4. A general guideline to crop tolerance of mineral soil acidity.1

Slightly tolerant (pH 6.8-6.0) Moderately tolerant (pH 6.8-5.5) Very tolerant (pH 6.8-5.0)
Beet Leek Bean, snap Mustard Endive
Broccoli Lettuce Bean, lima Pea Potato
Cabbage Muskmelon Brussels sprouts Pepper Shallot
Cauliflower Okra Carrot Pumpkin Sweetpotato
Celery Onion Collard Radish Watermelon
Chard Spinach Corn Squash
Cucumber Strawberry
Eggplant Tomato
Kale Turnip
1 From Donald N. Maynard and George J. Hochmuth, Knott's Handbook For Vegetable Growers, 4th edition (1997). Reprinted by permission of John Wiley & Sons, Inc.


Table 5. Liming materials.

Amount of Material
to be used to equal
Material Formula 1 ton of Calcium Carbonate1 Neutralizing value'(%)
Calcium carbonate, calcite, hi-cal lime CaCO3 2,0001bs 100
Calcium-magnesium carbonate, dolomite CaCO3 MgCO3 1,8501bs 109
Calcium oxide, burnt lime CaO 1,1001bs 179
Calcium hydroxide, hydrated lime Ca(OH)2 1,5001bs 136
Calcium silicate, slag CaSi03 2,3501bs 86
Magnesium carbonate MgCO3 1,6801bs 119
1 Calcutated as (2000 x 100) /neutralizing value (%).
2 The higher the neutralizing value, the greater the amount of acidity that is neutralized per unit weight of material.


It is important that soil samples represent the field or
management unit to be fertilized. A competent soil test-
ing laboratory that uses calibrated methodologies should
analyze the samples. Not all laboratories can provide
accurate fertilizer recommendations for Florida soils. The
BMP program for vegetables requires the importance of
calibrated soil test.



LIMING

Current University of Florida standardized recommen-
dations call for maintaining soil pH between 6.0 and 6.5
(Table 4). However, some vegetables, such as watermelon,
will perform normally at lower soil pH as long as large
amounts of micronutrients are not present in the soil. A
common problem in Florida has been overliming, resulting
in high soil pH. Overliming and resulting high soil pH can
tie up micronutrients and restrict their availability to the
crop. Overliming also can reduce the accuracy with which
a soil test can predict the fertilizer component of the CNR.

It is important, however, not to allow soil pH to drop
below approximately 5.5 for most vegetable production,
especially where micronutrient levels in the soil may be
high due to a history of micronutrient fertilizer and micro-
nutrient-containing pesticide applications. When soil pH


decreases in such soils, the solubility of micronutrients can
increase to levels that may become toxic to plants.

Irrigation water from wells in limestone aquifers is an
additional source of liming material usually not considered
in many liming programs. The combination of routine
additions of lime and use of alkaline irrigation water has
resulted in soil pH greater than 8.0 for many sandy soils in
south Florida. To measure the liming effect of irrigation,
have a water sample analyzed for total bicarbonates and
carbonates annually, and the results converted to pounds
of calcium carbonate per acre. Include this information in
your decisions concerning lime.

It should be evident that liming (Table 5), fertilization
(Table 6), and irrigation programs are closely related to
each other. An adjustment in one program will often influ-
ence the other. To maximize overall production efficiency,
soil and water testing must be made a part of any fertilizer
management program.



MANURES

Waste organic products, including animal manures and
composted organic matter, contain nutrients (Table 7) that
can enhance plant growth. These materials decompose


Page 6







Chapter 2: Soil and Fertilizer Management for Vegetable Production in Florida


Table 6. Effect of some fertilizer materials on soil pH.


Fertilizer material


Ammonium nitrate
Ammonium sulfate
Anhydrous ammonia
Diammonium phosphate
Potassium chloride
Sodium-potassium nitrate
Nitrogen solutions
Normal (ordinary) superphosphate
Potassium nitrate
Potassium sulfate
Potassium-magnesium sulfate
Triple (concentrated) superphosphate
Urea


Approximate
calcium carbonate
equivalent (Ib)1
-1200
-2200
-3000
-1250 to -1550
0
+550
-759 to -1800
0
+520
0
0
0
-1700


A minus sign indicates the number of pounds of calcium carbonate needed to
neutralize the acid formed when one ton of fertilizer is added to the soil.



Table 7. Average nutrient concentration of selected
organic fertilizers.
Product N P205 K20
J % dry weight
Blood 13 2 1
Fish meal 10 6 0
Bone meal 3 22 0
Cotton seed meal 6 3 1.5
Peanut meal 7 1.5 1.2
Soybean meal 7 1.2 1.5
Dried commercial manure products
Stockyard 1 1 2
Cattle 2 3 3
Chicken 1.5 1.5 2



when applied to the soil, releasing nutrients that vegetable
crops can absorb and utilize in plant growth. The key to
proper use of organic materials as fertilizers comes in the
knowledge of the nutrient content and the decomposi-
tion rate of the material. Many laboratories offer organic
material analyses to determine specific nutrient contents.
Growers contemplating using organic materials as fertil-
izers should have an analysis of the material before deter-
mining the rate of application. In the case of materials
such as sludges, it is important to have knowledge about
the type of sludge to be used. Certain classes of sludge
are not appropriate for vegetable production, and in fact
may not be permitted for land application. Decomposition
rates of organic materials in warm sandy soils in Florida
are rapid. Therefore, there will be relatively small amounts
of residual nutrients remaining for succeeding crops.
Organic materials are generally similar to mixed chemical
fertilizers in that the organic waste supplies an array of


nutrients, some of which may not be required on a par-
ticular soil. For example, the P in poultry manure would
not be required on a soil already testing high in phosphate.
Usually application rates of organic wastes are determined
largely by the N content. Organic waste materials can con-
tribute to groundwater or surface water pollution if applied
in rates in excess of the crop nutrient requirement for a
particular vegetable crop. Therefore, it is important to
understand the nutrient content and the decomposition rate
of the organic waste material, and the P-holding capacity
of the soil.



N, P, K, NUTRIENT SOURCES

Nitrogen can be supplied in both nitrate and ammo-
niacal forms (Table 8). Nitrate-nitrogen is generally the
preferred form for plant uptake in most situations, but
ammoniacal N can be absorbed directly or after conver-
sion to nitrate-N by soil microbes. Since this rate of
conversion is reduced in cold, fumigated, or strongly
acidic soils, it is recommended that under such condi-
tions 25% to 50% of the N be supplied from nitrate
sources. This ratio is not as critical for unfumigated or
warm soils.

Phosphorus (P) can be supplied from several sources,
including normal and triple superphosphate, diammo-
nium phosphate, monopotassium phosphate, and mono-
ammonium phosphate. All sources can be effective for
plant nutrition on sandy soil. However, on soils that test
very low in native micronutrient levels, diammonium
phosphate in mixtures containing micronutrients reduces
yields when banded in large amounts. Availability of P
also can be reduced with use of diammonium phosphate
compared to use of triple superphosphate. Negative
effects of diammonium phosphate can be eliminated by
using it for only a portion of the P requirement and by
broadcasting this material in the bed.

Potassium (K) can also be supplied from several
sources, including potassium chloride, potassium sulfate,
potassium nitrate, and potassium-magnesium sulfate. If
soil-test-predicted amounts of K fertilizer are adhered
to, there should be no concern about the K source or its
relative salt index.



CA, S, AND MG

The secondary nutrients calcium (Ca), sulfur (S), and
magnesium (Mg) have not been a common problem in
Florida. Calcium usually occurs in adequate supply for
most vegetables when the soil is limed. If the Mehlich- 1
soil Ca index is above 300 ppm, it is unlikely that there
will be a response to added Ca. Maintaining correct mois-
ture levels in the soil by irrigation will aid in Ca supply


Page 7







Vegetable Production Handbook


Table 8. Some commonly used fertilizer sources.

Nutrient Fertilizer source Nutrient content (%)


Nitrogen (N)


Phosphorus (P205)



Potassium (K20)





Calcium (Ca)





Magnesium (Mg)



Sulfur (S)






Boron (B)



Copper (Cu)






Iron (Fe)


Manganese (Mn)


Molybdenum (Mo)

Zinc (Zn)


Ammonium nitrate
Ammonium sulfate
Calcium nitrate
Diammonium phosphate
Potassium nitrate (nitrate of potash)
Urea
Sodium-potassium nitrate (nitrate of soda-potash)
Normal (ordinary) superphosphate
Triple (concentrated) superphosphate
Diammonium phosphate
Monopotassium phosphate
Potassium chloride (muriate of potash)
Potassium nitrate
Potassium sulfate (sulfate of potash)
Potassium-magnesium sulfate (sulfate of potash-magnesia)
Sodium-potassium nitrate
Monopotassium phosphate
Calcic limestone
Dolomite
Gypsum
Calcium nitrate
Normal superphosphate
Triple superphosphate
Dolomite
Magnesium sulfate
Magnesium oxide
Potassium-magnesium sulfate
Elemental sulfur
Ammonium sulfate
Gypsum
Normal superphosphate
Magnesium sulfate
Potassium-magnesium sulfate
Potassium sulfate
Borax
Fertibor1
Granubor1
Solubor1
Copper sulfate, monohydrate
Copper sulfate, pentahydrate
Cupric oxide
Cuprous oxide
Copper chloride
Chelates (CuEDTA)
(CuHEDTA)
Ferrous sulfate
Ferric sulfate
Chelates (FeHEDTA)
Manganous sulfate
Manganous oxide
Chelates (MnEDTA)
Ammonium molybdate
Sodium molybdate
Zinc sulfate
Zinc oxide
Zinc chloride
Chelates (ZnEDTA)
(ZnHEDTA)


Mention of a trade name does not imply a recommendation over similar materials.


34
21
15.5
18
13
46
13
20
46
46
53
60
44
50
22
14
34
32
22
23
19
20
14
11
10
55
11
97
24
18
12
14
22
18
11
14.9
14.3
20.5
35
25
75
89
17
13
6
20
20
5 to 12
28
68
5 to 12
54
39
36
80
50
6 to 14
6 to 10


Page 8







Chapter 2: Soil and Fertilizer Management for Vegetable Production in Florida


Table 9. Recommendations for foliar applications of plant
nutrients.

Foliar application
Nutrient Source (lb product per acre)
Boron Borax 2 to 5
Solubor1 1 to 1.5
Copper Copper sulfate 2 to 5
Iron Ferrous sulfate 2 to 3
Chelated iron 0.75 to 1
Manganese Manganous sulfate 2 to 4
Molybdenum Sodium molybdate 0.25 to 0.50
Zinc Zinc sulfate 2 to 4
Chelated zinc 0.75 to 1
Calcium Calcium chloride 5 to 10
Calcium nitrate 5 to 10
Magnesium Magnesium sulfate 10 to 15
Mention of a trade name does not imply a recommendation over similar
materials.



to the roots. Calcium is not mobile in the plant; therefore,
foliar sprays of Ca are not likely to correct deficiencies. It
is difficult to place enough foliar-applied Ca at the growing
point of the plant on a timely basis.

Sulfur deficiencies have seldom been documented for
Florida vegetables. Sulfur deficiency would most likely
occur on deep, sandy soils low in organic matter after
leaching rains. If S deficiency has been diagnosed, it can
be corrected by using S-containing fertilizers such as
magnesium sulfate, ammonium sulfate, potassium sulfate,
normal superphosphate, or potassium-magnesium sulfate.
Using one of these materials in the fertilizer blend at levels
sufficient to supply 30 to 40 lb S/A should prevent S defi-
ciencies.

Magnesium deficiency may be a problem for vegetable
production; however, when the Mehlich-1 soil-test index
for Mg is below 15 ppm, 30-40 lb Mg/A will satisfy the
Mg CNR. If lime is also needed, Mg can be added by
using dolomite as the liming material. If no lime is needed,
then the Mg requirement can be satisfied through use
of magnesium sulfate or potassium-magnesium sulfate.
Blending of the Mg source with other fertilizer(s) to be
applied to the soil is an excellent way of ensuring uniform
application of Mg to the soil.



MICRONUTRIENTS

It has been common in Florida vegetable production to
routinely apply a micronutrient package. This practice has
been justified on the basis that these nutrients were inex-
pensive and their application appeared to be insurance for
high yields. In addition, there were few research data and a
lack of soil-test calibrations to guide judicious application


of micronutrient fertilizers. Compounding the problem has
been the vegetable industry's use of micronutrient-contain-
ing pesticides for disease control. Copper (Cu), manganese
(Mn), and zinc (Zn) from pesticides have tended to accu-
mulate in the soil.

This situation has forced some vegetable producers to
overtime in an effort to avoid micronutrient toxicities. Data
have now been accumulated which permit a more accu-
rate assessment of micronutrient requirements (Table 3).
Growers are encouraged to have a calibrated micronutrient
soil test conducted and to refrain from shotgun micronutri-
ent fertilizer applications. It is unlikely that micronutrient
fertilizers will be needed on old vegetable land, especially
where micronutrients are being applied regularly via rec-
ommended pesticides. A micronutrient soil test every 2 to
3 years will provide recommendations for micronutrient
levels for crop production.



FOLIAR FERTILIZATION

Foliar fertilization should be thought of as a last resort
for correcting a nutrient deficiency (Table 9). The plant
leaf is structured in such a way that it naturally resists
easy infiltration by fertilizer salts. Foliar fertilization
most appropriately applies to micronutrients and not to
macronutrients such as N, P, and K. Foliar applications of
N, P, and/or K are not needed where proper soil-directed
fertilizer programs are in use. Leaves cannot absorb suf-
ficient nutrients (without burning the leaves) to correct
any deficiency. Some benefit from macronutrient foliar
sprays probably results when nutrients are washed by rain
or irrigation water off the leaf surface into the soil. The
nutrient then may enters the plant via the roots. Amounts
of macronutrients recommended on the label of most com-
mercial foliar products are so minuscule compared to nutri-
tion derived from the soil that benefit to the plant is highly
unlikely. Additionally, fertilizer should only be added if
additional yield results, and research with foliar-nutrient
applications has not clearly documented a yield increase
for vegetables.

In certain situations, temporary deficiencies of Mn,
Fe, Cu, or Zn can be corrected by foliar application.
Examples include vegetable production in winter months
when soils are cool and roots cannot extract adequate
amounts of micronutrients, and in cases where high pH
(marl and Rockdale soils) fixes broadcast micronutrients
into unavailable forms. Micronutrients are so termed
because small, or micro, amounts are required to satisfy
the CNR. Such micro amounts may be supplied ade-
quately through foliar applications to correct a temporary
deficiency.


Page 9







Vegetable Production Handbook


Boron is highly immobile in the plant. To correct boron
deficiencies, small amounts of boron must be applied fre-
quently to the young tissue or buds.

Any micronutrient should be applied only when a spe-
cific deficiency has been clearly diagnosed. Do not make
unneeded applications of micronutrients. There is a fine
line between adequate and toxic amounts of these nutri-
ents. Indiscriminate application of micronutrients may
reduce plant growth and restrict yields because of toxic-
ity. Compounding the problem is the fact that the micro-
nutrients can accumulate in the soil to levels which may
threaten crop production on that soil. An important part of
any micronutrient program involves careful calculations of
all micronutrients being applied, from all sources.



LIQUID VS. DRY FERTILIZER

There is no difference in response of crops to similar
amounts of nutrients when applied in either liquid or dry
form. Certain situations (use of drip irrigation or injection
wheel) require clear or true solutions. However, sidedress
applications of fertilizer can be made equally well with dry
or liquid forms of nutrients.

The decision to use liquid or dry fertilizer sources
should depend largely on economics and on the type of
application equipment available. The cost per unit of nutri-
ent (e.g., dollars per unit of actual N) and the combination
of nutrients provided should be used in any decision-mak-
ing process.



CONTROLLED-RELEASE FERTILIZERS (CRF)

Several brands of controlled-release fertilizers are avail-
able for supplying N. Some vegetables increase in yield
when controlled-release fertilizers, such as polymer-coated
or sulfur-coated urea, or isobutylidene-diurea, are used
to supply a portion of the N requirement. Although more
expensive, these materials may be useful in reducing fertil-
izer losses through leaching, in decreasing soluble salt dam-
age, and in supplying adequate fertilizer for long-term crops
such as strawberry or pepper. Controlled-release potassium
fertilizers also have been demonstrated to be beneficial
for several vegetables. It is essential to match the nutrient
release pattern of the CRF with the crop's uptake pattern.



SOLUBLE SALTS

Overfertilization or placement of fertilizer too close to
the seed or root leads to soluble salt injury or "fertilizer
burn." Fertilizer sources differ in their capacity to cause
soluble salt injury. Therefore, where there is a history of
soluble salt problems, or where irrigation water is high in


soluble salts, choose low-salt index fertilizer sources, and
broadcast or split-apply the fertilizer.



STARTER FERTILIZER

A true starter fertilizer is a soluble fertilizer, generally
high in P, used for establishment of young seedlings and
transplants. Starter fertilizers generally work best if a small
amount of N and K is present along with the P. Starters
represent a very small percentage of the overall fertilizer
amount but are very important in establishing crops in
cool, damp soils. They can be applied with the planter at 2
inches to the side of the seed and 2 inches deep or can be
dissolved in the transplant water and applied in the furrow.



FERTILIZER PLACEMENT

Fertilizer rate and placement must be considered togeth-
er. Banding low amounts of fertilizer too close to plants
can result in the same amount of damage as broadcasting
excessive amounts of fertilizer in the bed.

Because P movement in most soils is minimal, it should
be placed in the root zone. Banding is generally considered
to provide more efficient utilization of P by plants than
broadcasting. This is especially true on the high P-fixing
calcareous soils. Where only small amounts of fertilizer P
are to be used, it is best to band. If broadcasting P, a small
additional amount of starter P near the seed or transplant
may improve early growth, especially in cool soils. The
modified broadcast method where fertilizer is broadcast
only in the bed area provides more efficient use of fertilizer
than complete broadcasting.

Micronutrients can be broadcast with the P and incorpo-
rated in the bed area. On the calcareous soils, micronutri-
ents, such as Fe, Mn, and B, should be banded or applied
foliarly.

Since N and, to a lesser extent, K are mobile in sandy
soils, they must be managed properly to maximize crop
uptake. Plastic mulch helps retain these nutrients in the
soil. Under non-mulched systems, split applications of
these nutrients must be used to reduce losses to leaching.
Here, up to one-half of the N and K may be applied to the
soil at planting or shortly after that time. The remaining
fertilizer is applied in one or two applications during the
early part of the growing season. Splitting the fertilizer
applications also will help reduce the potential for soluble
salt damage to the plants.

When using plastic mulch, fertilizer placement depends
on the type of irrigation system (seep or drip) and on
whether drip tubing or the liquid fertilizer injection wheel
are to be used.


Page 10







Chapter 2: Soil and Fertilizer Management for Vegetable Production in Florida


With seep irrigation, all P and micronutrients should be
incorporated in the bed. Apply 10 to 20% (but not more) of
the N and K with the P. The remaining N and K should be
placed in narrow bands on the bed shoulders, the number
of which depend on the crop and number of rows per bed.
These bands should be placed in shallow (2- to 21/2-inch-
deep) grooves. This placement requires that adequate bed
moisture be maintained so that capillarity is not broken.
Otherwise, fertilizer will not move to the root zone.

Excess moisture can result in fertilizer leaching.
Fertilizer and water management programs are linked.
Maximum fertilizer efficiency is achieved only with close
attention to water management.

Under either system above, fertilizing with drip irriga-
tion or with a liquid fertilizer injection wheel might be
suitable alternatives to the placement of all N and K in or
on the bed prior to mulching.

In cases where supplemental sidedressing of mulched
crops is needed, applications of liquid fertilizer can be
made through the mulch with a liquid fertilizer injection
wheel (Fig. 2-4). This implement is mounted on a tool bar
and, using 30 to 40 psi pressure, injects fertilizer through a
hole pierced in the mulch.



SUPPLEMENTAL FERTILIZER APPLICATIONS
AND BMPS
In practice, supplemental fertilizer applications allow
vegetable growers to numerically apply fertilizer rates
higher than the standard IFAS recommended rates when
growing conditions require to do so. The two main grow-
ing conditions that may require supplemental fertilizer
applications are leaching rains and extended harvest peri-
ods. Applying additional fertilizer under the following
three circumstances is part of the current IFAS fertilizer
recommendations. Supplemental N and K fertilizer appli-
cations may be made under three circumstances:

1. For vegetable crops grown on bare ground with seep-
age irrigation and without drip irrigation, a 30 lbs/
acre of N and /or 20 lbs/acre of K20 supplemental
application is allowed after a leaching rain. A leach-
ing rain occurs when it rains at least 3 inches in 3
days, or 4 inches in 7 days.

2. For all vegetable crops grown on any production
system with one of the IFAS recommended irrigation
scheduling methods, a supplemental fertilizer appli-
cation is allowed when nutrient levels in the leaf or
in the petiole fall below the sufficiency ranges. For
bare ground production, the supplemental amount
allowed is 30 lbs/acre of N and/or 20 lbs/acre of K20.
For drip irrigated crops, the supplemental amount


allowed is 1.5 to 2.0 lbs/A/day for N and/or K20 for
one week.

3. Supplemental fertilizer applications are allowed
when, for economical reasons, the harvest period has
to be longer than the typical harvest period. When
the results of tissue analysis and/or petiole testing are
below the sufficiency ranges, a supplemental 30 lbs/
acre N and/or 20 lbs/acre of K20 may be made for
each additional harvest for bare ground production.
For drip-irrigated crops, the supplemental fertilizer
application is 1.5 to 2.0 lbs/A/day for N and/or K20
until the next harvest. A new leaf analysis and/or
petiole analysis is required to document the need for
additional fertilizer application for each additional
harvest.



DOUBLE-CROPPING

Successive cropping of existing mulched beds is a good
practice in order to make effective use of the polyethylene
mulch and fumigant (Fig. 2-5). Double-cropping also can
make use of residual fertilizer in the beds. If fertilizer-N
applications and amounts were properly managed for the
first crop, then there should be negligible amounts of N-
fertilizer remaining in the beds. The practice of adding
extra fertilizer to the beds when planting the first crop,
thinking that this fertilizer will aid growth of the second
crop is strongly discouraged. The extra fertilizer could con-
tribute to soluble-salt damage to the first crop, and might
still be leached from the root zone before the second crop
is established.

A drip-irrigation system can be used to supply adequate
nutrition to each crop in a double crop system. In most
cases, only N and K may be needed for the second crop.
Amounts of P and micronutrients (if any) used for the
first crop will likely remain adequate for the second crop
as well. Soil testing of a sample taken from the bed away
from any fertilizer bands will help determine P or micro-
nutrient needs, assuming that these nutrients were broad-
cast in the bed prior to planting the first crop.

If N for the first crop was not applied in excess of the
CNR, then the second crop should receive an amount of
N equal to its own CNR. Potassium requirements of the
second crop can be determined as for P in cases where the
K for the first crop was incorporated in the bed. Potassium
requirements for the second crop are more difficult to
determine in cases where K for the first crop was banded.
A moderate amount of residual K will probably remain in
the bed from the application to the first crop. Therefore, K
requirements for the second crop will likely be slightly less
than the CNR value for the chosen crop.


Page 11







Vegetable Production Handbook


Once the crop fertilizer requirements have been ascer-
tained, the needed nutrition may be applied through the
drip system. Where drip irrigation is not being used, a
liquid injection wheel can be used to place fertilizer in the
bed for the second crop.



LINEAR BED FOOT (LBF) SYSTEM FOR
FERTILIZER APPLICATION

The University of Florida Extension Soil Testing
Laboratory (ESTL) employs the Standardized Fertilizer
Recommendation System in which all recommendations
are expressed in lb/A. These fertilizer rates are based upon
typical distances between bed centers for each crop (Table
10). Table 10 also indicates the typical number of planting
rows within each bed. Conversions of fertilizer rates from
lb/A to lb/100 LBF, based upon these typical bed spacings,
are shown in Table 11.

Use of lb/100 LBF as a fertilizer rate assures that an
appropriate rate of fertilizer will be applied, regardless of
the total number LBF in the cropped area. In other words,


Table 10. Typical bed spacings for vegetables grown in
Florida.

Vegetable Typical Rows of plants
Spacing1 (ft) per bed
Broccoli 6 2
Muskmelon 5 1
Cabbage 6 2
Pepper 6 2
Cauliflower 6 2
Summer squash 6 2
Cucumber 6 2
Strawberry 4 2
Eggplant 6 1
Tomato 6 1
Lettuce 4 2
Watermelon 8 1
1 Spacing from the center of one bed to the center of an adjacent bed.


use of lb/A to express the fertilizer rate requires an adjust-
ment based upon actual cropped area.

In reality, the goal is to provide a specific concentra-
tion of nutrients to plant roots; that is, a specific amount of
fertilizer within a certain volume of soil. This conceptual
approach makes sense because most plant roots are con-
fined within the volume of soil comprising the bed, espe-
cially under the polyethylene in the full-bed mulch system.

See Table 11 for the conversion of fertilizer rates in lb/A
to lb/100 LBF. This table is used correctly by 1) determin-
ing the typical bed spacing from Table 10 for the crop; 2)
locating the column containing the recommended fertilizer
rate in lb/A; and 3) reading down the column until reach-
ing the row containing the typical row spacing. This rate,
in lb/100 LBF, should be used even in situations where the
grower's bed spacing differs from the typical bed spacing.



IRRIGATION MANAGEMENT

Water management and fertilizer management are
linked. Changes in one program will affect the efficiency
of the other program. Leaching potential is high for the
mobile nutrients such as N and K; therefore, over irriga-
tion can result in movement of these nutrients out of the
root zone. This could result in groundwater pollution in
the case of N. The goal of water management is to keep
the irrigation water and the fertilizer in the root zone.
Therefore, growers need knowledge of the root zone of the
particular crop so that water and fertilizer inputs can be
managed in the root zone throughout the season.

With increased pressure on growers to conserve water
and to minimize the potential for nutrient pollution, it
becomes extremely important to learn as much as pos-
sible about irrigation management. For more informa-
tion, see Chapter 3, Principles and Practices of Irrigation
Management for Vegetables, which is part of this publica-
tion.


Table 11. Conversion of fertilizer rates in lb/A to lb/100 LBF.

Typical bed Recommended fertilizer rate in Ib/A (N, P205, or K20)
spacing (ft) 20 40 60 80 100 120 140 160 180 200
Resulting fertilizer rate in Ib/100 LBF (N, P205, or K20)
3 0.14 0.28 0.41 0.55 0.69 0.83 0.96 1.10 1.24 1.38
4 0.18 0.37 0.55 0.73 0.92 1.10 1.29 1.47 1.65 1.83
5 0.23 0.46 0.69 0.92 1.15 1.38 1.61 1.84 2.07 2.30
6 0.28 0.55 0.83 1.10 1.38 1.65 1.93 2.20 2.48 2.76
8 0.37 0.73 1.10 1.47 1.84 2.20 2.57 2.94 3.31 3.68


Page 12







Chapter 2: Soil and Fertilizer Management for Vegetable Production in Florida


PLANT TISSUE ANALYSIS

Analysis of plants for nutrient concentration provides a
good tool to monitor nutrient management programs. There
are basically two approaches to plant tissue testing:stan-
dard laboratory analyses based on dried plant parts; and the
plant sap testing procedures. Both procedures have value
in nutrient management programs for vegetable crops, each
having its own advantages and disadvantages.

Standard laboratory analyses can be very accurate and
are the most quantitative procedure. However, they can be
time consuming for most diagnostic situations in the field.
Standard laboratory analysis involves analyzing the most-
recently-matured leaf of the plant for an array of nutrients.
The resulting analyses are compared against published
adequate ranges for that particular crop. Laboratory results
that fall outside the adequate range for that nutrient may
indicate either a deficiency or possibly a toxicity (espe-
cially in the case of micronutrients). The most-recently-
matured leaf serves well for routine crop monitoring and
diagnostic procedures for most nutrients. However, for the
immobile nutrients such as Ca, B, and certain other micro-
nutrients, younger leaves are generally preferred.

Several plant sap quick test kits have been calibrated for
N and K for several vegetables in Florida (Fig. 2-6). These
testing kits analyze fresh plant sap for N and K. Quick
test kits offer speed of analysis however, are less quantita-
tive than standard laboratory procedures. However, quick
tests are accurate enough and if properly calibrated are a
valuable tool for on-the-spot monitoring of plant nutrient
status with the goal of making fine adjustments in fertilizer
application programs, especially for those involving drip
irrigation.



DRIP IRRIGATION/FERTIGATION

Drip irrigation has become a very important water
management tool for Florida vegetable growers (Fig. 2-7).
Approximately 60,000 acres of vegetables are produced
with drip irrigation yearly in Florida. Many drip irrigation
users have turned to fertigation (applying nutrients through
the irrigation tube) to gain better fertilizer management
capability. In most situations, N and K are the nutrients
injected through the irrigation tube. Split applications of N
and K through irrigation systems offers a means to capture
management potential and reduce leaching losses. Other
nutrients, such as P and micronutrients, are usually applied
to the soil rather than by injection. This is because chemi-
cal precipitation can occur with these nutrients and the
high calcium carbonate content of our irrigation water in
Florida.

Nutrient management through irrigation tubes involves
precise scheduling of N and K applications. Application


rates are determined by crop growth and resulting nutri-
ent demand. Demand early in the season is small and thus
rates of application are small, usually on the order of '/2
to /4 lb of N or K20 per acre per day. As the crop grows,
nutrient demand increases rapidly so that for some vegeta-
ble crops such as tomato the demand might be as high as 2
lb of N or K20 per day. Schedules of N and K application
have been developed for most vegetables produced with
drip irrigation in Florida. Schedules for these crops are pre-
sented in the crop chapters in this book.



SOIL PREPARATION

A well-prepared seed or planting bed is important
for uniform stand establishment of vegetable crops. Old
crop residues should be plowed down well in advance of
crop establishment. A 6- to 8-week period between plow-
ing down of green cover crops and crop establishment is
recommended to allow the decay of the refuse. Freshly
incorporated plant material promotes high levels of damp-
ing-off organisms such as Pythium spp. and Rhizoctonia
spp. Turning under plant refuse well in advance of crop-
ping reduces damping-off disease organisms. Land should
be kept disced if necessary to keep new weed cover from
developing prior to cropping.

Chisel plowing is beneficial in penetrating and break-
ing tillage pan layers in fields. If plastic mulch culture is
practiced, debris and large undecayed roots will create
problems in preparing good beds over which mulch will be
applied.



BEDDING

Fields where seepage irrigation is used or fields prone
to flooding should be cropped using raised beds. Beds
generally range from 3 to 8 inches in height, with high
beds of 6 to 8 inches preferred where risk of flooding is
greatest. Raised beds dry faster than if the soil was not
bedded, requiring closer attention to irrigation manage-
ment especially early in the season when root systems are
limited. Raised beds promote early season soil warming
resulting in somewhat earlier crops during cool seasons.
Many raised beds covered with mulch in north Florida in
sandy, well drained soils do not need to be as high as 6 to
8 inches as they do in poorly drained soils.

Bedding equipment may include single or double bed-
ding discs, and curved bedding blades. After the soil is cut
and thrown into a loose bed the soil is usually firmed with
a bed press. In unmulched production the loosely formed
bed may be leveled off at the top by dragging a board or
bar across the bed top. Boarding-off the raised beds is
common in unmulched watermelon production in central
and northern Florida. Mulching requires a smooth, well-


Page 13







Vegetable Production Handbook


pressed bed for efficient heat transfer from black mulch
to the soil. Adequate soil moisture is essential in forming
a good bed for mulching. Dry sandy soils will not form a
good bed for a tight mulch application. Overhead irrigation
is sometimes needed to supply adequate moisture to dry
soils before bedding.



COVER CROPS

Cover crops between vegetable cropping seasons can
provide several benefits. The use of cover crops as green
manure can slightly increase soil organic matter during
the growing season. Properties of soil tilth can also be
improved with turning under good cover crops. The cover
can reduce soil losses due to erosion from both wind and
water. Many crops are effective at recycling nutrients left
from previous crops. Recycling of nutrients is becoming
an increasingly important issue in protecting groundwater
quality.

The selection of a cover crop is based on the seasonal
adaptation and intended use for the crops. Vegetable pro-
duction in south Florida results in cover crops needed dur-
ing the late spring and summer months. Summer grasses
like sorghum or sudan/sorghum hybrids have been popular
among Florida producers as a summer cover. Pearl millet
is another grass crop providing excellent cover but is not
as popular as sudan/sorghum. Both pearl millet and sudan/
sorghum provide a vigorous tall crop with high biomass
production and are excellent at competing with weeds.
The cover crop selected should have resistance to nema-
todes or at least serve as a relatively poor nematode host.
Warm-season legumes such as velvet bean and hairy indigo
have been noted for their resistance to nematodes. Hairy
indigo has been unpopular because of its habit of reseed-
ing. It also has hard seed and produces volunteers in later
years. Alyceclover is another warm season legume with
one variety, F1-3, having nematode resistance. Alyceclover
produces an excellent quality hay for producers that can
utilize hay from a cover crop.

In north Florida, vegetable crops are established in the
spring and early fall. Cover crops are generally utilized
during the winter months of November through March.
Popular cool season grasses have included rye, wheat,
oats, or ryegrass. The traditional crop rotation for water-
melon growers has included the use of well-established
bahia grass pastures followed by a crop of watermelon.
The acreage of available bahia grass pastures for rotation
has been reduced and these pastures are difficult to find
for many growers. As a result, growers are being forced to
more intensively crop fields. Cover crops would be help-
ful in managing the land. When bahia grass sod is used for
production, the extensive root system must be very well


tilled well in advance of the cropping season to break up
the clumps, especially if plastic mulch will be used. Deep
plowing is best to facilitate decomposition of the grass
roots and stems.


WINDBREAKS


The use of windbreaks is an important cultural practice
consideration in many vegetable crops and in most states
in the United States. Windbreaks used in agriculture are
barriers, either constructed or vegetative, of sufficient
height to create a windless zone to their leeward or pro-
tected side. Strong winds, even if a few hours in duration,
can cause injury to vegetable crops by: whipping plants
around, abrasion with solid particles ("sand blasting"), cold
damage, and plant dessication. Windbreaks are especially
important to protect young plants that are most susceptible
to wind damage. Abrasion to plants from wind-blown sand
is of concern in most of Florida where sandy soils are
commonly used for production. Spring winds in Florida
are expected each year. Many of the vegetable crops pro-
duced in central and north Florida are at a young and very
susceptible stage during these windy spring periods. Strips
of planted rye are generally recommended for temporary
windbreaks in those ares (Fig. 2-8). Sugarcane can also
serve as a more permanent windbreak in South Florida
(Fig. 2-9).

The primary reasons windbreaks have been used in veg-
etable crops has been to reduce the physical damage to the
crop from the whipping action of the wind and to reduce
sand blasting. Young, unprotected vegetable crops stands
can be totally lost from these two actions. Many Florida
vegetable crops are grown using plastic mulch culture.
Young cucurbit crops, such as watermelon and cantaloupe
grown on plastic are especially susceptible to the whipping
action of the wind. Vines of these crops eventually become
anchored to the soil between mulched beds, however,
young vines can be whipped around in circles for several
days until they become anchored. The physical damage
by whipping and sandblasting can reduce stand, break or
weaken plants, open wounds which can increase disease,
and reduce flowering and fruit set.

Windbreaks can also help conserve moisture for the
crop. Effective windbreaks reduce the wind speed reach-
ing the crops. This reduces both direct evaporation from
the soil and transpiration losses from the plant. Improved
moisture conditions can help in early season stand estab-
lishment and crop growth. Air temperatures around
the crop can also be slightly modified by windbreaks.
Temperature on the leeward side of the windbreaks can be
slightly higher than if no windbreak were present. Early
season crop growth is also greater when windbreaks are


Page 14







Chapter 2: Soil and Fertilizer Management for Vegetable Production in Florida


utilized. Workers in several states reported increased earli-
ness when rye strips were effectively used as windbreaks.

A field layout to include windbreaks must be properly
designed to achieve the maximum benefit. The windbreaks
should be positioned perpendicular to the prevailing winds.
This determination is perhaps more difficult in Florida than
most other states, however, windbreaks planned for protec-
tion in the spring should generally protect against winds
from the west or northwest. Wind protection is achieved as
long as the barrier is a least three feet high, the vegetation
is sufficiently dense, and is positioned perpendicular to the
prevailing wind.

The height of the windbreak is the most important fac-
tor in determining how far apart the strips must be located.
Research on windbreaks has been conducted indicating
wind protection is afforded to a distance of 6 to 20 times
the height of the barrier. Field research with rye strips
showed protection was afforded up to a distance of 10
times the height of the barrier. For example, a healthy crop
of rye planted in a 5 to 8 ft wide strip using a grain drill
and reaching a height of 3 ft would afford wind protection
up to 30 ft from the rye strip. If the same rye strip reached
a height of 4 ft it would afford protection up to 40 ft from
the rye strip. These examples use the calculation of protec-
tion afforded up to 10 times the height of an adequate rye
strip.

Crops such as small grains, trees, shrubs, or sugarcane
are "permeable" barriers in comparison to solid barriers
such as smooth constructed walls. Solid barriers are less
effective windbreaks than permeable barriers. Wind pass-
ing over a solid barrier is deflected over and creates an
area of turbulence on the protected side and returns to the
ground quickly.

Another type of technology that can provide excellent
protection from high winds is the use of plastic row tun-
nels. Polyethylene or polypropylene materials are place
over the plants in a row and held in place. Tunnels are
popular for many vegetable crops, especially cucurbits
such as cantaloupes. The cover is removed from cucurbits
when the first female blooms appear to allow honeybees to
pollinate the crops. Tunnels are generally used in conjunc-
tion with rye strips because the tunnels have to be removed
and once removed the crop is susceptible to wind.

The most widely used windbreak in vegetable crops
across the United States is the rye strip method. Winter or
cereal rye (Secale cereale) is the preferred small grain for
this use because the seed is usually cheaper, it provides
more growth under cold temperatures and results in the
highest plant habit. In some cases the field is solid seeded
and later tilled in only the narrow strips where the plastic
mulch bed is applied. This leaves a narrow strip of rye


between each bed or row and is generally a very effective
windbreak design. This design can result in more difficul-
ties in weed management if weeds emerge in the rye strips,
however, the rye can be managed with herbicide in certain
crops.

The most common use of rye as a windbreak is plant-
ing it into strips. Seeding rye should be done in the fall
(October December) for protection in a spring crop. The
strips are typically 5-8 ft wide and planted with a grain
drill. The windbreak is a valuable component of the crop-
ping system and should be treated as such. A top dressing
or two of a fertilizer (at least nitrogen) will promote suffi-
cient early spring growth of the rye to maximize effective-
ness as a windbreak. Unfertilized rye strips on low fertility
soil will often result in poor, thin, short strips of rye that
will be less effective as a windbreak.

The spacing of the rye strips every 30 to 40 feet allows
them to also be used as drive roads or spray roads in the
field. These are generally necessary in managing most
vegetable crops and therefore the rye strips are not taking
away cropped areas of the field.

When the rye strips have served their purpose, they can
be removed by mowing, rototilling, or discing. If mow-
ing is used in a plastic mulched field, the mower should
not throw the rye stems into the plastic area because holes
will be pierced in the mulch. One insect management con-
cern in using rye strips in Florida is their attractiveness to
thrips. Rye strips also seem to be an excellent environment
for beneficial insects, especially lady beetles. If thrips need
to be managed in the rye strips, the strips could be sprayed
just before the rye is mowed or tilled out. Once the rye is
destroyed, the thrips migrate to the crops so control would
be more effective while they are still on the rye strips.


Page 15







Page 16 is
missing from
the original
document






UF UNIVERSITY of
UFFLORIDA
IFAS Extension
Chapter 3. 2010-2011

Principles and Practices of Irrigation Management for Vegetables

E.H. Simonne, M.D. Dukes and L. Zotarelli


This section contains basic information on vegetable
water use and irrigation management, along with some
references on irrigation systems. Proper water manage-
ment planning must consider all uses of water, from the
source of irrigation water to plant water use. Therefore,
it is very important to differentiate between crop water
requirements and irrigation or production system water
requirements. Crop water requirements refer to the actual
water needs for evapotranspiration (ET) and plant growth,
and primarily depend on crop development and climatic
factors which are closely related to climatic demands.
Irrigation requirements are primarily determined by crop
water requirements, but also depend on the characteristics
of the irrigation system, management practices and the soil
characteristics in the irrigated area.



BEST MANAGEMENT PRACTICES (BMP)
FOR IRRIGATION
BMPs have historically been focused on nutrient man-
agement and fertilizer rates. However, as rainfall or irri-
gation water is the vector of off-site nutrient movement
of nitrate in solution and phosphate in sediments as well
as other soluble chemicals, proper irrigation management
directly affects the efficacy of a BMP plan. The irrigation
BMPs in the "Water Quality/Quantity Best Management
Practices for Florida Vegetable and Agronomic Crops"
(accessible at www.floridaagwaterpolicy.com) manual
cover all major aspects of irrigation such as irrigation
system design, system maintenance, erosion control, and
irrigation scheduling.



USES OF IRRIGATION WATER
Irrigation systems have several uses in addition to water
delivery for crop ET. Water is required for a preseason
operational test of the irrigation system to check for leaks
and to ensure proper performance of the pump and power
plant. Irrigation water is also required for field prepara-
tion, crop establishment, crop growth and development,
within-season system maintenance, delivery of chemicals,
frost protection, and other uses such as dust control.


Field Preparation
Field preparation water is used to provide moisture
to the field soil for tillage and bed formation. The water
used for field preparation depends on specific field cul-
tural practices, initial soil moisture conditions, the depth
to the natural water table, and the type of irrigation sys-
tem. Drip-irrigated fields on sandy soils often require an
additional irrigation system for field preparation because
drip tubes are not installed until after the beds have been
formed. Thus, many drip irrigated vegetable fields may
also require an overhead or subirrigation system for field
preparation. For example, many strawberry production
fields have sprinkler irrigation systems already installed
for frost protection. These systems are also used for field
preparation and may apply one or more inches of water for
this purpose. Subirrigated fields will use the same system
for field preparation as well as for crop establishment,
plant growth needs and frost protection. Subirrigation
water management requirements depend on the soil char-
acteristics within the irrigated field and surrounding areas.
Sufficient water must be provided to raise the water table
level as high as 18 to 24 inches below the soil surface.
Water is required to fill the pores of the soil and also sat-
isfy evaporation and subsurface runoff requirements. As
a rough guide, 1.0 to 2.5 inches of water are required for
each foot of water table rise. For example, a field with a
pre-irrigation water table 30 inches deep may need about 2
inches of water to raise the water table to 18 inches, while
a pre-irrigation water table at 48 inches may require 5
inches of water for the same result.

Crop Establishment
Vegetables that are set as transplants, rather than direct
seeded require irrigation for crop establishment in excess
of crop ET. Establishment irrigations are used to either
keep plant foliage wet by overhead sprinkler irrigation (to
avoid desiccation of leaves) or to maintain high soils mois-
ture levels until the root systems increase in size and plants
start to actively grow and develop. Establishment irriga-
tion practices vary among crops and irrigation systems.
Strawberry plants set as bare-root transplants may require
10 to 14 days of frequent intermittent overhead irrigation
for establishment prior to irrigation with the drip system.
The amount of water required for crop establishment can
range widely depending on crop, irrigation system, and
climate demand. Adequate soil moisture is also needed for
the uniform establishment of direct-seeded vegetable crops.


Page 17







Vegetable Production Handbook


Table 1 .Application efficiency for water delivery systems
used in Florida

Irrigation system Application efficiency (Ea)
Overhead 60-80%
Seepage1 20-70%
Drip2 80-95%
1 Ea greater than 50% are not expected unless tailwater recovery is used
2 With or without plastic mulch



Crop Growth and Development
Irrigation requirements necessary to meet the ET needs
of a crop depend on the type of crop, field soil characteris-
tics, irrigation system type and capacity, and stage of crop
development. Different crops have growth characteristics
that result in different relative water use rates. Soils vary
in texture and hydraulic characteristics such as available
water-holding capacity (AWHC) and capillary movement.
Because sands generally have very low AWHC values (3%
to 6% is common), a 1% change in AWHC affects irriga-
tion practices.

Water Application (Irrigation requirement)
Irrigation systems are generally rated with respect to
application efficiency (Ea), which is the fraction of the
water that has been applied by the irrigation system and
that is available to the plant for use (Table 1). Applied
water that is not available to the plant may have been
lost from the crop root zone through evaporation or wind
drifts of spray droplets, leaks in the pipe system, surface
runoff, subsurface runoff, or deep percolation within the
irrigated area. Irrigation requirements (IR) are determined
by dividing the desired amount of water to provide to the
plant (ETc), by the Ea as a decimal fraction (Eq.[1]). For
example, if it is desired to apply 0.5 inches to the crop with
a 75% efficient system, then 0.5/0.75 = 0.67 inches would
need to be pumped. Hence, when seasonal water needs are
assessed, the amount of water needed should be based on
the irrigation requirement and all the needs for water, and
not only on the crop water requirement. For more informa-
tion, consult IFAS bulletin 247 "Efficiencies of Florida
agricultural irrigation systems" (http://edis.ifas.ufl.edu/
AE 110) and bulletin 265 "Field evaluation of microirriga-
tion water application uniformity" (http://edis.ifas.ufl.edu/
AE094).

Eq. [1] Irrigation requirement =
Crop water requirement / Application efficiency
IR = ETc/Ea


Fertigation/Chemigation
Irrigation systems are often used for delivery of chemi-
cals such as fertilizers, soil fumigants, or insecticides. The
crop may require nutrients when irrigation is not required,
e.g. after heavy rainfall. Fertilizer injection schedules
based on soil tests results are provided in each crop pro-
duction chapter of this production guide. Fertigation
should not begin until the system is pressurized. It is rec-
ommended to always end a fertigation/ chemigation event
with a short flushing cycle with clear water to avoid the
accumulation of fertilizer or chemical deposits in the irri-
gation system, and/or rinse crop foliage. The length of the
flushing cycle should be 10 minutes longer than the travel
time of the fertilizer from the irrigation point to the farthest
point of the system.

System Maintenance
Irrigation systems require periodic maintenance
throughout the growing season. These activities may
require system operation during rainy periods to ensure
that the system is ready when needed. In addition, drip
irrigation systems may require periodic maintenance to
prevent clogging and system failure. Typically, cleaning
agents are injected weekly, but in some instances more fre-
quent injections are needed.

Frost Protection
For some crops, irrigation is used for frost protection
during winter growing seasons. For strawberry production,
sprinkler irrigation is primarily used with application rates
of about 0.25 inches per hour during freeze events. Water
freezes at 32F, while most plant tissues freeze at lower
temperatures. Overhead freeze protection is efficient for
air temperature as low as 26-28F, but seldom below. For
vegetable fields with subirrigation systems, the relatively
higher temperature of groundwater can be used for cold
protection. Growers may also irrigate to raise the water
table throughout the field. Frost protection water require-
ments vary and depend on the severity and duration of
freeze events, the depth to the existing water table level,
and field hydraulic characteristics.

Other Uses
Other irrigation uses vary according to the type of crop,
system characteristics, and field location. Some examples
include: periodic overhead irrigation for dust control; wet-
ting of dry row middles to settle dust and prevent sand
from blowing during windy conditions; and, wetting of
roadways and drive aisles to provide traction of farm
vehicles.



IRRIGATION SCHEDULING

Irrigation scheduling consists simply of applying water
to crops at the "right" time and in the "right" amount and
it is considered an important BMP. The characteristics


Page 18







Chapter 3: Principles and Practices of Irrigation Management for Vegetables


of the irrigation system, crop needs, soil properties, and
atmospheric conditions must all be considered to properly
schedule irrigations. Poor timing or insufficient water
application can result in crop stress and reduced yields
from inappropriate amounts of available water and/or
nutrients. Excessive water applications may reduce yield
and quality, are a waste of water, and increase the risk of
nutrient leaching.



Table 2. Levels of water management and corresponding
irrigation scheduling method
Water
Mgt. Level Irrigation scheduling method
0 Guessing (irrigate whenever), not recommended
1 Using the "feel and see" method, see ftp://ftp-fc.
sc.egov.usda.gov/MT/www/technical/soilmoist.pdf
2 Using systematic irrigation (Example: % in. every
4th day; or 2hrs every day)
3 Using a soil water tension measuring tool or soil
moisture sensor to start irrigation
4 Schedule irrigation and apply amounts based on
a budgeting procedure and checking actual soil
water status
51 Adjusting irrigation to plant water use (ETo), and
using a dynamic water balance based on a budget-
ing procedure and plant stage of growth, together
with using a soil water tension measuring tool or
soil moisture sensor
1 Recommended method


A wide range of irrigation scheduling methods is used
in Florida, with corresponding levels of water management
(Table 2). The recommended method (level 5) for schedul-
ing irrigation (drip or overhead) for vegetable crops is to
use together: the crop water requirement method that takes
into account plant stage of growth associated with mea-
surements of soil water status, and guidelines for splitting
irrigation (see below). A typical irrigation schedule con-
tains (1) a target crop water requirement adjusted to crop
stage of growth and actual weather demand, (2) adjustment
of irrigation application based on soil moisture, (3) a rule
for splitting irrigation, (4) a method to account for rainfall,
and (5) record keeping (Table 3). For seepage irrigation,
the water table should be maintained near the 18-inch
depth (measured from the top of the bed) at planting and
near the 24-inch depth when plants are fully grown. Water
tables should be maintained at the proper level to ensure
optimum moisture in the bed without leading to oversatu-
ration of the root zone and potential losses of nutrients.
Water tables can be monitored with a section of PVC pipe
sunk in the soil with a calibrated float inside the PVC pipe.
The calibrated float can be used to determine the exact
level of the water table.

Soil Water Status, Soil Water Tension and
Soil Volumetric Water Content
Generally, two types of sensors may be used for mea-
surements of soil water status, those that measure soil
water potential (also called tension or suction) and those
that measure volumetric water content directly. Soil
water tension (SWT) represents the magnitude of the suc-
tion (negative pressure) the plant roots have to create to


Table 3. Summary of irrigation scheduling guidelines for vegetable crops grown in Florida.

Irrigation scheduling Irrigation system 1
component Seepage 2 Drip 3
1- Target water application rate Keep water table between 18 and 24 inch depth Historical weather data or crop evapotranspiration (ETc) calculated
from reference ET or Class A pan evaporation


2- Fine tune application with soil
moisture measurement
3- Determine the contribution
of rainfall


4- Rule for splitting irrigation


Monitor water table depth with observation wells

Typically, 1 inch rainfall raises the water table by
1 foot


Not applicable. However, a water budget can be
developed


5-Record keeping Irrigation amount applied and total rainfall
received 4
Days of system operation
1 Efficient irrigation scheduling also requires a properly designed and maintained irrigation system
2 Practical only when a spodic layer is present in the field
3 On deep sandy soils


Maintain soil moisture level in the root zone between 8 and 15 cbar
(or 8% and 12% available soil moisture
Poor lateral water movement on sandy and rocky soils limits the
contribution of rainfall to crop water needs to (1) foliar absorption
and cooling of foliage and (2) water funneled by the canopy through
the plan hole.
Irrigations greater than 12 and 50 gal/1OOft (or 30 min and 2 hrs for
drip tapes with medium flow-rate) when plants are small and fully
grown, respectively are likely to push the water front being below the
root zone
Irrigation amount applied and total rainfall received 4
Daily irrigation schedule


4 Required by the BMPs


4 Required by the BMPs


Page 19







Vegetable Production Handbook


free soil water from the attraction of the soil, and move it
into the root cells. The dryer the soil, the higher the suc-
tion needed, hence, the higher SWT. SWT is commonly
expressed in centibars (cb) or kilopascals (kPa; 1cb =
1kPa; 7kPa = ipsi). For most vegetable crops grown on
the sandy soils of Florida, SWT in the rooting zone should
be maintained between 6 (slightly above field capacity)
and 15 cb. Because of the low AWHC of Florida soils,
most full-grown vegetable crops will need to be irrigated
daily. During early growth, irrigation may be needed only
two to three times weekly. SWT can be measured in the
field with moisture sensors or tensiometers. For more
information on SWT measuring devices, consult IFAS cir-
cular 487 'Tensiometers for soil moisture measurement and
irrigation scheduling' available at http://edis.ifas.ufl.edu/
AE146 and bulleting 319 "Tensiometer service, testing and
calibration" available at http://edis.ifas.ufl.edu/AE086.

Within the category of volumetric sensors, capacitance
based sensors have become common in recent years due to
a decrease in cost of electronic components and increased
reliability of these types of sensors. However, sensors
available on the market have substantially different accura-
cies, response to salts, and cost. Soil moisture sensors are
detailed in the publication, "Field Devices for Monitoring
Soil Water Content" (http://edis.ifas.ufl.edu/AE266). All
methods under this definition estimate the volume of water
in a sample volume of undisturbed soil [ft3/ft3 or percent-
age]. This quantity is useful for determining how saturated
the soil is (or, what fraction of total soil volume is filled
with the soil aqueous solution). When it is expressed in
terms of depth (volume of water in soil down to a given
depth over a unit surface area (inches of water)), it can be
compared with other hydrologic variables like precipita-
tion, evaporation, transpiration and deep drainage.

Practical Determination of Soil Field Capacity Using
Volumetric Soil Moisture Sensors
It is very important that the irrigation manager under-
stands the concept of "field capacity" to establish an irri-
gation control strategy goals of providing optimum soil
moisture for plant growth, productivity, and reduction of
fertilizer nutrient leaching. Figure 1 represents volumetric
soil water content (VWC) at depth of 0-6 inches measured
by a capacitance sensor during a period of 4 days. For
the soil field capacity point determination, it is necessary
to apply an irrigation depth that resulted in saturation of
the soil layer, in this particular case 0-6 inches. The depth
of irrigation applied was 4,645 gal/ac (equivalent to 0.17
in for overhead or seepage irrigation, or 34 gal/100ft for
drip irrigation with 6 ft bed centers in plasticulture) in a
single irrigation event. Right after the irrigation events,
there was a noticeable increase in soil moisture content.
The degree to which the VWC increases, however, is
dependent upon volume of irrigation, which is normally
set by the duration of irrigation event. For plastic mulched
drip irrigation in sandy soils, long irrigation events result


-h-li "f
A-. saluraflion
0 Irriogtin event
&0.16 *
0.14
0.12
0.10- e1id capacty .


s oil field capacity
0,04 I -
1 2 Day 3

Figure 1. Example of practical determination of soil field capacity at 0-6
inches soil depth after irrigation event using soil moisture sen-
sors.


in a relatively large increase in soil moisture in the area
below the drip emitter. The spike in soil moisture appears
to only be temporary, as the irrigation water rapidly drains
down beyond the 6-inch zone (observed by the decrease
in VWC). This rapid spike in soil water content indicates
that the VWC rapidly reaches a point above the soil water
holding capacity and the water percolated down to deeper
soil layers. Between end of day 1 and day 3 (Fig. 1), the
VWC declined at a constant rate due to some soil water
extraction by drainage, but most extraction due to evapo-
transpiration during the day. For sandy soils, the change in
the slope of drainage and extraction lines, in other words,
changing from "rapid" to "slower" decrease in soil water
content can be assumed as the "field capacity point". At
this time, the water has moved out from the large soil
pores (macropores), and its place has been taken by air.
The remaining pore spaces (micropores) are still filled with
water and will supply the plants with needed moisture.

Examples of Irrigation Scheduling Using Volumetric Soil
Moisture Sensor Devices
In this section, two examples of irrigation management
of vegetable crops in sandy soils using soil moisture sensor
readings stored in a data logger are provided: one example
with excessive ("over") irrigation (Fig. 2) and one with
adequate irrigation (Fig.3) using plasticulture. In Figure 2,
the irrigation events consisted of the application of a single
daily irrigation event of 4,718 gal/ac (equivalent to 0.18 in
for overhead or seepage irrigation, or 36 gal/100ft for drip
irrigation with 6-ft bed centers in plasticulture. After each
irrigation event, there was an increase in the soil water
content followed by rapid drainage. Large rainfall events
may lead to substantial increases in soil moisture content.
On day 2, right after the irrigation, a large rainfall of 0.44
inches occurred, which resulted in a second spike of soil
water content in the same day. The following irrigation
(day 3) started when the volumetric soil water content
was above the soil field capacity. In this case, the irriga-
tion event of the day 3 could have been safely skipped.
Between day 3 and 6, no irrigation was applied to the crop.


Page 20







Chapter 3: Principles and Practices of Irrigation Management for Vegetables


'0 16.



S
!0 10





50.08
o012


4 5 6 7 8 9 10 11 1213
Day


0o 16
C
o 14ii
u012

010 0
c
'E
0411,

PA.S0,


00A 1 I 1. 1. 1 T. I. f.


Figure 2. Example of excessive ("over") irrigation" of the upper soil layer (0
to 6 inch depth) moisture content for drip irrigation under plastic
mulched condition for sandy soils. Black line indicates volumetric
soil water content using soil moisture sensors. Grey line indicates
Irrigation event, single daily irrigation event with volume applica-
tion of 65 gal/00ft (0.18 in). Dotted line indicates soil field capac-
ity line. Arrows indicate rainfall events.




The volumetric water content decreased from 0.14 to 0.08
in3/in3. Due to the very low water holding capacity of the
sandy soils, skipping irrigation for several days could lead
to unneeded crop water stress especially during very hot
days or very windy days (when high evapotranspiration
rates may occur), or during flowering stage. Between day 6
and 10, large daily irrigation events were repeated, exceed-
ing the "safe irrigation zone", and leading to more water
drainage and nutrient leaching.

Conversely, Figure 3 shows "adequate" irrigation appli-
cations for a 10 day period. In this case, the irrigation
event will start exclusively when the volumetric soil water
content reaches an arbitrary threshold. For this particular
situation, the soil field capacity is known, the irrigation
events started when the volumetric soil moisture content
reached values below the soil field capacity (or 0.09 in3/
in3). However, to maintain the soil volumetric water con-
tent in the "safe irrigation zone", a previous determination
of the length of the irrigation is necessary, to avoid over
irrigation (additional information about irrigation depths
can be obtained in the IFAS bulletin AE72 "Microirrigation
in Mulched Bed Production Systems: Irrigation Depths" at
(http://edis.ifas.ufl.edu/AE049).

The example in Figure 3 received irrigation depth of
943 gal/ac (equivalent to 0.03 in for overhead or seepage
irrigation, or 6 gal/100ft for drip irrigation with 6-ft bed
centers in plasticulture, this irrigation depth was sufficient
to increase the volumetric water content to a given mois-
ture without exceeding the "safe irrigation zone". On aver-
age, the volumetric soil water content is maintained close
to the field capacity, keeping water and nutrients in the root
zone. For this particular example, there was no deep water
percolation. In addition, with the information of the soil


2 3 4 5 6 7 8D
Day


a 10


o ra
0(60


0.40 C
FC C
*0300
- 0.2011
*lt

0.11
0.00
II


Figure 3. Example of adequate irrigation management using soil moisture
sensors for monitoring the volumetric soil moisture content the
upper soil layer (0 to 6 inch depth), on drip irrigation under
plastic mulched condition for sandy soils. Black line indicates
volumetric soil water content using soil moisture sensors. Grey
line indicates Irrigation event, single daily irrigation event with
volume application of 943 gal/ac (0.03 in). Dotted line indicates
soil field capacity line. Arrows indicate rainfall events.



water status, the irrigation manager might decide to not
irrigate if the soil moisture content is at a satisfactory level.
For example, in day 8, due to a rainfall event of 0.04 in,
there was no need of irrigation because the soil moisture
was above the field capacity and the arbitrary threshold,
therefore the irrigation event of day 8 was skipped. On the
other hand, this "precise" irrigation management requires
very close attention by the irrigation manager. For a given
reason (such as pump issue), the irrigation was ceased in
day 5 and it was resumed late in day 6. As a result, soil
water storage decreased to a certain level, and if the water
shortage is prolonged, the plants would be water stressed.

Tips on Installation and Placing of Soil Moisture Sensor
Devices in Vegetable Fields
The use of soil moisture monitoring devices volumetricc
or soil water tension) has potential of save irrigation water
application in a given vegetable area by reducing the num-
ber of unnecessary irrigation events. However, the effec-
tiveness of the use of these sensors depends of a proper
installation in representative locations within vegetable
fields. These sensors may be used to monitor water table
levels in seepage irrigation.

Sensors should be buried in the root zone of the plants
to be irrigated. Most of the vegetable crops have 80% to
90% of the root zone in the upper 12 inches, which gener-
ally is the soil layer with higher water depletion by evapo-
transpiration. For vegetable crops cultivated in rows and
irrigated by drip tapes, the sensors should be installed 2-3
inches away from the plant row. For single row crops (such
as tomato, eggplant, or watermelon), the sensor should
be placed in the opposite side of the drip tape, for double
row crops (pepper, squash), the sensors should be placed in
between the drip tape and plant rows.


Page 21


I i'
a

13w





{0o03 In)
I I


1







Vegetable Production Handbook


Sensors need to be in good contact with the soil after
burial; there should be no air gaps surrounding the sensor.
Soil should be packed firmly but not excessively around
the sensor. In plasticulture, after the installation, the area
above the sensor should be recovered back with plastic and
sealed with tape.

Crop water requirement (ET)
Crop water requirements depend on crop type, stage
of growth, and evaporative demand. Evaporative demand


is termed evapotranspiration (ET) and may be estimated
using historical or current weather data. Generally, refer-
ence evapotranspiration (ETo) is determined for use as a
base level. By definition, ETo represents the water use
from a uniform green cover surface, actively growing, and
well watered (such as turf or grass covered area).

Historical daily averages of Penman-method ETo values
are available for six Florida regions expressed in units of
acre-inches and gallons per acre (Table 4).


Table 4. Historical Penman method reference evapotranspiration (ETo) for six Florida regions expressed in
day and (B) gallons per acre per day1.


(A) inches per


Month Northwest Northeast Central Central West Southwest Southeast
Inches per day


Gallons per acre per day2


2715
3530
4344
4616
4616
4073
3530
2444


1901
2172
2715
3801
4344
4344
4344
4073
3530
2715
1901
1629


1901
2715
3258
4344
4887
4887
4616
4616
3801
2987
2172
1629


1901
2715
3530
4344
4887
4887
4616
4344
3801
2987
2172
1629


2172
2987
3530
4616
4887
4887
4887
4616
4073
3258
2444
1901


2172
2987
3530
4616
4887
4616
4887
4344
3801
3258
2444
1901


1 Assuming water application over the entire area, i.e., sprinkler or seepage irrigation with 100% efficiency, See Table 1 for conversion for taking into account irrigation system
efficiency.
2 Calculation: for overhead or seepage irrigation, (B) = (A) x 27,150. To convert values for drip irrigation (C) use (C) = (B) x bed spacing / 435.6. For example for 6-ft bed spacing
and single drip line, C in Southwest Florida in January is C = 2,172 x 6/435.6 = 30 gal/100ft/day


Page 22







Chapter 3: Principles and Practices of Irrigation Management for Vegetables


While these values are provided as guidelines for
management purposes, actual values may vary above and
below these values, requiring individual site adjustments.
Actual daily values may be as much as 25% higher on days
that are hotter and drier than normal or as much as 25%
lower on days that are cooler or more overcast than nor-
mal. Real time ETo estimates can be found at the Florida
Automated Weather Network (FAWN) internet site (http://
fawn.ifas.ufl.edu). For precise management, SWT or soil
moisture should be monitored daily in the field.

Crop water use (ETc) is related to ETo by a crop coef-
ficient (Kc) which is the ratio of ETc to the reference
value ETo (Eq. [2]). Because different methods exist for
estimating ETo, it is very important to use Kc coefficients
which were derived using the same ETo estimation method
as will be used to determine the crop water requirements.
Also, Kc values for the appropriate stage of growth (Table
5; Fig. 4) and production system (Tables 6 and 7) must be
used.


With drip irrigation where the wetted area is limited and
plastic mulch is often used, Kc values are lower to reflect
changes in row spacing and mulch use. Plastic mulches
substantially reduce evaporation of water from the soil
surface. Associated with the reduction of evaporation is
a general increase in transpiration. Even though the tran-
spiration rates under mulch may increase by an average
of 10-30% over the season as compared to no-mulched
system, overall water use values decrease by an average of
10-30% due the reduction in soil evaporation. ETo may be
estimated from atmometers (also called modified Bellani
plates) by using an adjustment factor. During days without
rainfall, ETo may be estimated from evaporation from an
ET gauge (Ea) as ETo = Ea/0.89. On rainy days (>0.2 in)
ETo = Ea/0.84.

Eq. [2] Crop water requirement =
Crop coefficient x Reference evapotranspiration

ETc = Kc x ETo


Table 5. Description of stages of growth (plant appearance and estimated number of weeks) for most vegetable crops grown
in the Spring in Florida1.


Expected
growing
Crop Stage 1 Stage 2 Stage 3 Stage 4 Stage 5 season (weeks)
Bean Small plants Growing plants Pod enlargement Pod maturation 9-10


2-3
Cabbage, Cauliflower, Small plants
Chinese cabbage 2-3


Cantaloupe (musk-
melon)


Carrot

Cucumber

Eggplant


Potato


Onion

Pepper


6-in vine
1-2


Small plants
1-2
6-in vine
1-2


3-4
Growing plants
5-6
12-in vine
3-4

Growing plants
3-4
12-in vine
2-3


Small plants Growing plants
2-3 2-3


Small plants
(after hilling)
2-4


Large plants
(vegetative
growth)
4-6


Small plants Growing plants
2-3 2-3
Small plants Growing plants
2-4 4-5
Small plants Growing plants
2-3 2-3


2-3
Head development
3-4
First flower
3-4

Root development
5-7
Fruit production
6-7
Fruit production
6-7
First flower (tube
initiation and bulk-
ing)
3-5
Pod production
7-8
Bulb development
6-8
Pod production


7-8 1-2


2-3


Main fruit production Late fruit
2-3 production
2-3
Final growth
1-2
Late season
1-2
Late season


Maturation (top dies)
2-4


Late season
1-2
Maturation (top falls)
1-2
Last bloom


Last harvest
1


10-12

11-12


10-13

10-12

12-13

12-14


12-13

13-16

13-15


Page 23







Page 24


Table 5. Continued.


Vegetable Production Handbook


Expected
growing
Crop Stage 1 Stage 2 Stage 3 Stage 4 Stage 5 season (weeks)
Pumpkin (bush) Small plants First flower Fruit enlargement Harvest 9-11
2-3 2-3 5-6 1-2
Pumpkin (vining) 6-in vines 12-in vines Small fruit Large fruit Harvest 1-2 13-15
2-3 2-3 3-4 2-3
Radish Small plants Rapid growth 3-5
1-2 2-4
Strawberry Young plants Growing plants Early harvest Main harvest period Late harvest 23-30
October November December-January February-March April
Summer Squash Small plants Growing plants Fruit production Late fruit production 7-9
(crookneck, straight- 1-2 2-3 3-4 1
neck, zucchini)
Sweet corn Small plants Large plants Ear development 10-15
3-4 5-8 2-3
Sweetpotato Early vine Expanding vines Storage root Late season 13-17
growth 5-6 enlargement
2-3 6-10
Tomato Small plants 1st bloom 2nd-3rd bloom Harvest Late harvest 12-14
2-3 2-3 6-7 1-2 1-2
Watermelon 6-in vines 12-in vines Small fruit Large fruit Harvest 1-2 13-15
2-3 2-3 3-4 2-3
1 Same growth stages used for irrigation and fertilizer schedules; for South Florida, each stage may be 30% longer because of winter planting during short days.



Table 6. Crop coefficient estimates for use with the ETo values in Table 3 and growth stages in Table 4 for unmulched crops.
(Actual values will vary with time of planting, soil conditions, cultural conditions, length of growing season and
other site-specific factors)


Crop
All field-grown vegetables

Legumes: sandbean, lima bean and southernpea

Beet

Cole crops:
Broccoli, brussels sprouts
cabbage, cauliflower
Collards, kale, mustard, turnip

Carrot

Celery

Cucurbits: cucumber, cantaloupe, pumpkin, squash, watermelon

Lettuce: endive,
escarole
Okra


Growth Stage
1
2
3
4
3
4

3
4
3
4
3
4
3
4
3
4
3
4
3
4


Crop Coefficienti
0.202 to 0.403
Stage 14 value to Stage 3 value (See Figure 3-3)
0.955
0.855
1.00
0.90

0.95
0.805
0.905
1.005
1.00
0.70
1.00
0.90
0.90
0.70
0.95
0.90
1.005
0.905







Chapter 3: Principles and Practices of Irrigation Management for Vegetables


Table 6. Continued.

Crop Growth Stage Crop Coefficienti
Onion (dry) 3 0.95
4 0.75
Onion (green) 3 and 4 0.95
Parsley 3 1.005
Potato 3 1.10
4 0.70
Radish 3 0.80
4 0.75
Spinach 3 0.95
4 0.90
Sweet corn 3 1.10
4 1.00
Sweetpotato 3 1.105
4 0.705
adapted from Doorenbos, J., and Pruitt, W. 0. 1977. Crop water requirements. Irrigation and Drainage Paper No. 24, (rev.) FAO, Rome
and Allen, R.G., L.S.Pereira, D. Raes, and M. Smith. 1998. Crop evapotranspiration: Guidelines for computing crop water requirements
Food and Agriculture Organization of the United Nations, Rome.
2 low plant population; wide row spacing

3 high plant population; close row spacing
4 0.30 or Kc value from Stage 1
5 values estimated from similar crops


Table 7. Crop coefficient estimates (Kc) for use with ETo values in Table 3 and growth stages in Table 4 for selected crops
grown in a plasticulture system.1
Growth Crop Crop
Crop Stage Coefficient (Kc) Crop Growth Stage Coefficient (Kc)
Cantaloupe1 1 0.35 Strawberry 1 0.4
2 0.6 (4-ft bed centers) 2 2 0.5
3 0.85 3 0.6
4 0.85 4 0.8
5 0.85 5 0.8
Cucumber1 1 0.25 Tomato 1 0.4
2 0.5 (6-ft bed centers) 3 2 0.75
3 0.9 3 1.0
4 0.75 4 1.0
5 0.85
Summer squash1 1 0.3 Watermelon 1 0.3
2 0.55 (8-ft bed center)1 2 0.5
3 0.9 3 0.7
4 0.8 4 0.9
5 0.8
1 Adapted from Tables 12 and 25 in Allen, R.G., L.S.Pereira, D. Raes, and M. Smith. 1998. Crop evapotranspiration: guidelines for computing crop water requirements Food and
Agriculture Organization of the United Nations, Rome.
2 Adapted from Clark et al.(1993) Water Requirements and Crop Coeffcients for Tomato Production in Southwest Florida. Southwest Florida Water Management District, Brandon,
FL.
3 Adapted from Clark et al. 1996. Water requirements and crop coefficients of drip-irrigated strawberry plants. Transactions of the ASAE 39:905-913.


Page 25







Vegetable Production Handbook


SOIL WATER HOLDING CAPACITY AND THE
NEED TO SPLIT IRRIGATIONS
Appropriate irrigation scheduling and matching irriga-
tion amounts with the water holding capacity of the effec-
tive root zone may help minimize the incidence of excess
leaching associated with over-irrigation. In Florida sandy
soils, the amount of water that can be stored in the root
zone and be available to the plants is limited. Usually, it
is assumed that approximately 0.75 inches of water can
be stored in every foot of the root zone. Only half of that
should be used before next irrigation to avoid plant stress
and yield reduction (this will help maintain SWT below 15
cb). Any additional water will be lost by deep percolation
below the root zone.

Table 8 gives approximate amount of water that can be
applied at each event in Florida sandy soil under differ-
ent production systems. When the calculated volume of
water to be applied in one day exceeds the values in Table
7, then it is necessary to split applications. The number
of split irrigations can be determined by dividing the irri-
gation requirement (Eq. [1]) by the numbers in Table 8,
and rounding up the result to the nearest whole number.
Splitting irrigation reduces both risks of water loss through
deep percolation and nutrient leaching. Sandy soil with the
available water holding capacity of 0.75 in/ft was assumed
in these calculations. If a soil contains more clay or organ-
ic matter the amount of water applied during one irrigation
event and stored in the root zone can be increased. It is
recommended to check the depth of wetting after irrigation
to assure that the water is not lost from the roots by dig-
ging out a perpendicular profile to the drip line and observ-
ing the wetted pattern.


1.2
Drip irrigated
1.0 tomatoes

I0.8-

8 0.6- Drip irrigated
S / / strawberries
o 0.4-

0.2-

0.0 i i i
1 2 3 4 5 6
Month of growth

Figure 4. Crop coefficient of drip irrigated tomato and strawberry.


Example
As an example, consider drip irrigated tomatoes on
6-ft center beds, grown under plastic mulch production
system in the Central West area (sandy soils). For plants
in growth Stage 5 the crop coefficient is 0.85 (Table 7). If
this period of growth occurred in May, the corresponding
ETo value is 4,914 gal/ac/day (Table 4). Daily crop water
use would be estimated as:

ETcrop = (0.85) x (4,914 gal/ac/day)
= 4,177 gal/ac/day

If the drip irrigation system can apply water to the root
zone of the crop with an application efficiency of 85%, the
irrigation requirement would be

Irrigation Requirement = (4,177 gal/ac/day) / (0.80)
= 5,221 gal/ac/day

If the maximum water application in one irrigation
event for this type of soil is 1,700 gal/ac/irrigation, then
the irrigation will have to be split:

Number of events = (5,221 gal/acre/day) / (1,700 gal/acre/day/
irrigation event) = 3.1, rounded up to 4 irrigation events each of
5,221 / 4 = 1,305 gal/acre

Therefore, in this example, four irrigations of 1,305
gal/ac each will be needed to replace ETc, not exceed the
soil water holding capacity. This amount of water would
be a good estimate for scheduling purposes under average
growth and average May climatic conditions. However,
field moisture plant status should be also monitored to
determine if irrigation levels need to be increased or
reduced. While deficit irrigation will reduce fruit size and
plant growth, excessive irrigation may leach nutrients from
the active root system. This may also reduce plant growth.


Page 26







Page 27


Table 8. Maximum water application (in gallons per acre and in gallons/1001fb) in one irrigation event for various production
systems on sandy soil (available water holding capacity 0.75 in/ft and 50% soil water depletion). Split irrigations may
be required during peak water requirement.




Segetable crop







1.5 36 54 72 4 Lettuce, strawberry 109
CL- L- CL








6 Broccoli, okra, cabbage, pepper, cauliflower, summer squash o o
M CM cM Vegetable crop M CM CM CM
1.0 24 36 48 4 Lettuce, strawberry 109 2,600 3,800 5,100
5 Cantaloupe 87 2,100 3,100 4,100
6 Broccoli, okra, cabbage, pepper, cauliflower, summer squash,
pumpkin (bush), eggplant, tomato 73 1,700 2,600 3,500
8 Watermelon, pumpkin (vining) 55 1,300 1,900 2,600
1.5 36 54 72 4 Lettuce, strawberry 109
5 Muskmelon 87 3,800 5,800 7,600
6 Broccoli, okra, cabbage, pepper, cauliflower, summer squash,
pumpkin (bush), eggplant, tomato 73 3,100 4,700 6,200
8 Watermelon, pumpkin (vining) 55 2,600 3,900 5,200
1,900 3,000 3,900






Page 28 is
missing from
the original
document






UF UNIVERSITY of
UF FLORIDA
IFAS Extension
2010-2011


Nematodes and Their Management

J.W. Noling


Plant parasitic nematodes are microscopic roundworms
which live in the soil and attack the roots of plants. Crop
production problems induced by nematodes therefore
generally occur as a result of root dysfunction, reducing
rooting volume and foraging and utilization efficiency of
water and nutrients. Many different genera and species of
nematodes can be important to crop production in Florida.
In many cases a mixed community of plant parasitic
nematodes is present in a field, rather than having a single
species occurring alone. In general, the most widespread
and economically important nematode species include the
root-knot nematode, Meloidogyne spp., and sting nema-
tode, Belonolaimus longicaudatus. The host range of these
nematodes, as with others, includes most if not all of the
commercially grown vegetables within the state (Table 1).
Yield reductions can be extensive but vary significantly
between plant and nematode species. In addition to the
direct crop damage caused by nematodes, many of these
species predispose plants to infection by fungal or bacterial
pathogens or transmit virus diseases, which contributes to
additional yield reductions.


BIOLOGY & LIFE HISTORY

Most species of plant parasitic nematodes have a rela-
tively simple life cycle consisting of the egg, four larval
stages and the adult male and female. Development of
the first stage larvae occurs within the egg where the first
molt occurs. Second stage larvae hatch from eggs to find
and infect plant roots or in some cases foliar tissues. Host
finding or movement in soil occurs within surface films
of water surrounding soil particles and root surfaces.
Depending on species, feeding will occur along the root
surface or in other species like root-knot, young larval
stages will invade root tissue, establishing permanent feed-
ing sites within the root. Second stage larvae will then molt
three times, to become adult male or female. For most spe-
cies of nematodes, as many as 50 to 100 eggs are produced
per female, while in others such as root-knot, upwards of
2,000 may be produced. Under suitable environmental con-
ditions, the eggs hatch and new larvae emerge to complete
the life cycle within 4 to 8 weeks depending on tempera-
ture. Nematode development is generally most rapid within
an optimal soil temperature range of 70 to 80F.


Table 1. Plant parasitic nematodes known to be of economic importance to vegetable crops in Florida.







Cyst
aW
a) CD c2 oD 9 CM

Nematode cc C) C) C) C) __ C Cc Cc W cn C Q u
Root Knot x x x x x x x x x x x x x
Sting x x x x x x x x x x x x x
Stubby Root x x x x x x x x x x
Root Lesion x
Cyst x
Awl x x
Stunt x
Lance x
Spiral x
Ring
Dagger
Bud and Leaf
Reniform x x


Page 29


Chapter 4.







Vegetable Production Handbook


SYMPTOMS

Typical symptoms of nematode injury can involve both
aboveground and belowground plant parts. Foliar symp-
toms of nematode infestation of roots generally involve
stunting and general unthriftiness, premature wilting and
slow recovery to improved soil moisture conditions, leaf
chlorosis (yellowing) and other symptoms characteristic of
nutrient deficiency. An increased rate of ethylene produc-
tion, thought to be largely responsible for symptom expres-
sion in tomato, has been shown to be closely associated
with root-knot nematode root infection and gall formation.
Plants exhibiting stunted or decline symptoms usually
occur in patches of variable growth rather than as a overall
decline of plants within an entire field.

The time in which symptoms of plant injury occur is
related to nematode population density, crop susceptibil-
ity, and prevailing environmental conditions. For example,
under heavy nematode infestation, crop seedlings or trans-
plants may fail to develop, maintaining a stunted condition,
or die, causing poor or patchy stand development. Under
less severe infestation levels, symptom expression may
be delayed until later in the crop season after a number of
nematode reproductive cycles have been completed on the
crop. In this case aboveground symptoms will not always
be readily apparent early within crop development, but
with time and reduction in root system size and function,
symptoms become more pronounced and diagnostic.

Root symptoms induced by sting or root-knot nema-
todes can oftentimes be as specific as above ground
symptoms. Sting nematode can be very injurious, causing
infected plants to form a tight mat of short roots, assuming
a swollen appearance. New root initials generally are killed
by heavy infestations of the sting nematode, a symptom
reminiscent of fertilizer salt burn. Root symptoms induced
by root-knot cause swollen areas (galls) on the roots of
infected plants. Gall size may range from a few spheri-
cal swellings to extensive areas of elongated, convoluted,
tumorous swellings which result from exposure to multiple
and repeated infections. Symptoms of root galling can in
most cases provide positive diagnostic confirmation of
nematode presence, infection severity, and potential for
crop damage.



DAMAGE

For most crop and nematode combinations the damage
caused by nematodes has not been accurately determined.
Most vegetable crops produced in Florida are susceptible
to nematode injury, particularly by root-knot and sting
nematodes (Table 1). Plant symptoms and yield reductions
are often directly related to preplant infestation levels in


soil and to other environmental stresses imposed upon the
plant during crop growth. As infestation levels increase so
then does the amount of damage and yield loss. In general,
the mere presence of root-knot or sting nematodes suggests
a potentially serious problem, particularly on sandy ground
during the fall when soil temperatures favor high levels
of nematode activity. At very high levels, typical of those
which might occur under double cropping, plants may be
killed. Older transplants, unlike direct seed, may tolerate
higher initial population levels without incurring a signifi-
cant yield loss.



FIELD DIAGNOSIS & SAMPLING

Because of their microscopic size and irregular field
distribution, soil and root tissue samples are usually
required to determine whether nematodes are causing poor
crop growth or to determine the need for nematode man-
agement. For nematodes, sampling and management is a
preplant or postharvest consideration because if a prob-
lem develops in a newly planted crop there are currently
no postplant corrective measures available to rectify the
problem completely once established. Nematode density
and distribution within a field must therefore be accurately
determined before planting, to guarantee that a representa-
tive sample is collected from the field. Nematode species
identification is currently only of practical value when
rotation schemes or resistant varieties are available for
nematode management. This information must then be
coupled with some estimate of the expected damage to for-
mulate an appropriate nematode control strategy.

Advisory or Predictive Sample: Samples taken to
predict the risk of nematode injury to a newly planted
crop must be taken well in advance of planting to allow
for sample analysis and treatment periods if so required.
For best results, sample for nematodes at the end of the
growing season, before crop destruction, when nematodes
are most numerous and easiest to detect. Collect soil and
root samples from 10 to 20 field locations using a cylin-
drical sampling tube, or if unavailable, a trowel or shovel.
Since most species of nematodes are concentrated in the
crop rooting zone, samples should be collected to a soil
depth of 6 to 10 inches. Sample in a regular pattern over
the area, emphasizing removal of samples across rows
rather than along rows. One sample should represent no
more than 10 acres for relatively low-value crops and
no more than 5 acres for high-value crops. Fields which
have different crops (or varieties) during the past season
or which have obvious differences either in soil type or
previous history of cropping problems should be sampled
separately. Sample only when soil moisture is appropriate
for working the field, avoiding extremely dry or wet soil
conditions.


Page 30







Chapter 4: Nematodes


Diagnostics on Established Plants: Roots and soil
cores should be removed to a depth of 6 to 10 inches from
10 to 20 suspect plants. Avoid dead or dying plants, since
dead or decomposing roots will often harbor few nema-
todes. For seedlings or young transplants, excavation of
individual plants maybe required to insure sufficient quan-
tities of infested roots and soil. Submission of additional
samples from adjacent areas of good growth should also be
considered for comparative purposes.

For either type of sample, once all soil cores or samples
are collected, the entire sample should then be mixed thor-
oughly but carefully, and a 1 to 2 pint subsample removed
to an appropriately labeled plastic bag. Remember to
include sufficient feeder roots. The plastic bag will prevent
drying of the sample and guarantee an intact sample upon
arrival at the laboratory. Never subject the samples) to
overheating, freezing, drying, or to prolonged periods of
direct sunlight. Samples should always be submitted imme-
diately to a commercial laboratory or to the University of
Florida Nematode Assay Laboratory for analysis. If sample
submission is delayed, then temporary refrigeration is rec-
ommended at temperatures of 40 to 60F.

Recognizing that the root-knot nematode causes the for-
mation of large swollen areas or galls on the root systems
of susceptible crops, relative population levels and field
distribution of this nematode can be largely determined
by simple examination of the crop root system for root
gall severity. Root gall severity is a simple measure of the
proportion of the root system which is galled. Immediately
after final harvest, a sufficient number of plants should be
carefully removed from soil and examined to character-
ize the nature and extent of the problem within the field.
In general, soil population levels increase with root gall
severity. This form of sampling can in many cases provide
immediate confirmation of a nematode problem and allows
mapping of current field infestation. As inferred previously,
the detection of any level of root galling usually suggests
a nematode problem for planting a susceptible crop, par-
ticularly within the immediate areas from which the galled
plants) were recovered.



GENERAL MANAGEMENT CONSIDERATIONS

Currently nematode management considerations include
crop rotation of less susceptible crops or resistant variet-
ies, cultural and tillage practices, use of transplants, and
preplant nematicide treatments. Where practical, these
practices are generally integrated into the summer or win-
ter 'off-season' cropping sequence. It should be recognized
that not all land management and cultural control practices
are equally effective in controlling plant parasitic nema-
todes and varying degrees of nematode control should be
expected. These methods, unlike other chemical methods,


tend to reduce nematode populations gradually over time.
Farm specific conditions, such as soil type, temperature,
and moisture, can be very important in determining wheth-
er different cultural practices can be effectively utilized for
nematode management.



CULTURAL PRACTICES

Crop Rotation
For crop rotation to be effective, crops unsuitable for
nematode infection, growth, or reproduction must be
introduced into the rotation sequence. In most of Florida
it is not uncommon to observe a multispecies community
of nematodes all occurring within the same field. Under
these circumstances it may not be possible to find a rota-
tion or cover crop that will effectively reduce populations
of all nematode pests, particularly if root-knot and sting
nematodes occur in combination In this case, crop rotations
detrimental to root-knot, which is generally the most diffi-
cult to control, should be selected. In some cases, resistant
crop varieties are available which can be used within the
rotation sequence to minimize problems to some species of
root-knot but not sting nematodes.

Use of poor or nonhost cover crops within the rotation
sequence, may in some cases offer an effective approach
to nematode control. Two leguminous cover crops adapt-
able for managing soil populations of sting or root-knot
nematode include hairy indigo (Indigofena hirsuta) and
American jointvetch (Aeschynomene americana). Sorghum
is also a popular cover crop restoring large amounts of
soil organic matter, but is a good host for sting and stubby
root nematode but not root-knot. Most of the small grains
commonly used as winter cover crops in central and north
Florida, such as rye, millet, barley, wheat or oats, can sup-
port limited reproduction of root-knot nematode. To avoid
an increase in root-knot populations, these crops should
only be planted when soil temperatures are below 650F, a
threshold temperature for nematode activity.

Cover crop rotations with some pastureland grasses
(particularly pangola digitgrass, and to some extent Bahia-
grass, and bermuda grass) have significantly reduced, but
not eliminated, root-knot nematodes. In north Florida, long
term (6- to 9- year) pastureland rotations allowed econom-
ic watermelon production within root-knot infested fields.
It should be recognized that as the crop rotation period is
shortened or eliminated, nematode problems will inten-
sify accordingly. Other perennial legumes currently under
evaluation may play an important role in future nematode
management programs.

For cover crops to be most effective, stands must be
established quickly and undesirable weeds which can
serve as alternative hosts must be controlled. Given that


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Vegetable Production Handbook


many different weeds serve as alternative plant hosts
to nematodes (i.e. nutsedges), it may not be possible to
manage root-knot nematode with crop rotation unless an
integrated program to manage weeds is also considered
and implemented within the field. With many cover crops,
rapid stand establishment has been a significant problem.
Similarly, economic crop rotation sequences are often
further complicated by lack of crop management skills,
specialized equipment to grow and harvest the crop, or by
the lack of closely located processing facilities or markets.
In some cases other measures should be considered such as
fallowing which is usually as efficient as crop rotation for
reducing field infestations of nematodes.

Fallowing
Clean fallow during the off-season is probably the sin-
gle most important and effective cultural control measure
available for nematodes. When food sources are no longer
readily available, soil population densities of nematodes
gradually decline with death occurring as a result of starva-
tion. Due to the wide host range of many nematode spe-
cies, weeds and crop volunteers must be controlled during
the fallow period to prevent nematode reproduction and
further population increase. At least two discing operations
are generally required to maintain clean fallow soil condi-
tions during the interim period between crops. Fallowing
by use of herbicides to deplete nematode populations is
a much slower process because the soil is not disturbed,
thereby subjecting nematodes from deeper soil layers to
the drying action of sun and wind. The unfavorable effects
of fallowing on soil organic matter and soil structure are
usually more than compensated for by the level of nema-
tode control achieved and the resulting increase in crop
productivity. When soil erosion is a potentially serious
problem other measures should be considered.

Biological Control
At present there are no effective, commercially avail-
able, biological control agents which can be successfully
used to control nematodes.

Biorational Compounds
The active ingredients of these compounds can best
be described as either microbial agents or derived toxins,
plant extracts or dried plant products, or simple blends of
fatty acids, stabilized colloids, or secondary alcohols. In
general, suitable and/or consistent nematode control and
crop yield enhancement has not been achieved with these
products. Further research characterizing the utility of
these compounds under different environmental conditions,
and the ways and means in which to increase their effec-
tiveness is necessary.

Plant Resistance
Use of nematode-resistant crop varieties has not been
extensively evaluated in Florida, but is often viewed as the


foundation of a successful integrated nematode manage-
ment program on all high value crops in which methyl bro-
mide is currently used. Commercially available nematode-
resistant varieties are currently available only for tomato,
pepper, southernpea, and sweet potato. In a resistant
variety, nematodes fail to develop and reproduce normally
within root tissues, allowing plants to grow and produce
fruit even though nematode infection of roots occurs. Some
crop yield loss can still occur however, even though the
plants are damaged less and are usually significantly more
tolerant of root-knot infection than that of a susceptible
variety.

In tomato, a single dominant gene (subsequently
referred to as the Mi gene) has been widely used in plant
breeding efforts and varietal development which confers
resistance to all of the economically importance spe-
cies of root-knot nematode found in Florida, including
Meloidogyne incognita, M. arenaria, and M. javanica.
Commercially resistant fresh market varieties, climati-
cally and horticulturally adapted for Florida are available
as an effective nematode management tactic in tomato.
Unfortunately, in previous research with resistant tomato
varieties, the resistance can fail as a result of the heat insta-
bility or apparent temperature sensitivity of the resistant
Mi gene. For example, previous research has demonstrated
threshold soil temperatures and incremental reductions in
nematode resistance with each degree above 780F, such
that at 91 F tomato plants are fully susceptible. This would
suggest that in Florida, use of these varieties may be better
suited for spring plantings when cooler soil temperatures
prevail.

In pepper, two root-knot nematode resistant varieties
('Carolina Belle' and 'Carolina Wonder') were released
from the USDA Vegetable Research Laboratory for com-
mercial seed increase in April 1997. Both varieties are
open pollinated, and homozygous for the root-knot nema-
tode resistant N gene. Preliminary research has demon-
strated that these varieties confer a high degree of resis-
tance to the root-knot nematode, however expression of
resistance is heat sensitive. Further research is necessary to
characterize the usefulness of these varieties under the high
soil temperature conditions of Florida. Further research
to incorporate the resistance genes into other commercial
available lines and varieties is also required. Like tomato,
use of these varieties may have to be restricted to spring
plantings when cooler soil temperatures prevail.

In addition, to problems of heat instability, the continu-
ous or repeated planting of resistant plant varieties will
almost certainly select for virulent races of Meloidogyne
capable of overcoming the resistance. Therefore the dura-
tion and/or utility of the resistance may be time-limited. In
previous studies with resistant tomatoes, resistance break-
ing nematode races develop within 1 to 3 years. Since new


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Chapter 4: Nematodes


races of the nematode can develop so rapidly, a system of
integrated control usually mandates the rotation of resistant
and non-resistant varieties to slow the selection process for
new virulent races. Recent trials in Florida have already
demonstrated the capacity of some species or races of
root-knot to reproduce and inflict damage upon a resistant
tomato variety. The results of this research have demon-
strated that even with a resistant variety, which was dam-
aged less than a susceptible variety, some consideration
of initial soil population levels of the root-knot nematode
must be observed to minimize tomato yield losses. Given
that significant yield losses can still occur, combined
efforts to manage soil populations to low levels prior to
planting must still be considered, particularly if tomatoes
are planted as a fall crop. If this situation develops, the
combination of a nematicide and resistant variety may also
comprise an option to reduce nematode populations to
acceptable levels.

Soil Amendments
Many different types of amendments and composted
materials have been applied to soil to suppress popula-
tions of plant parasitic nematode and improve crop yield
and plant health. Animal manures, poultry litter, and disk-
incorporated cover crop residues are typical examples of
soil amendments used in agriculture to improve soil quality
and as a means for enhancing biocontrol potential of soil.
Some amendments which contain chitin and inorganic
fertilizers that release ammoniacal nitrogen into soil sup-
press nematode populations directly and enhance the selec-
tive growth of microbial antagonists of nematodes. More
recently, composted municipal wastes and sludges have
been used to amend soil to improve soil fertility, organic
matter content, water holding capacity, nutrient retention,
and cation exchange capacity.

Suppression of soilborne pathogens via the incorpo-
ration or simple mulching of composted amendments
is reputedly based on enhanced microbial activity and
increased numbers of antagonists generated by decompo-
sition of the amendment in soil. Soils with a diversity of
beneficial microorganisms are more suppressive to patho-
gens than soils with little or no biological diversity. Other
possible mechanisms for pathogen suppression by com-
posts include direct inhibition of the pathogen or reduced
infectivity of the organisms into the plant host. Population
increases of beneficial organisms in soil appears to be the
direct result of environmental changes brought about by
the amendments after addition to soil. This suggests that to
sustain soil suppressiveness, amendments must be periodi-
cally reapplied to maintain the soil environment conducive
to antagonists.

The level to which soilborne pest and disease control
can be achieved is not only related to the type of material
but to the age of the compost. Nematode and disease sup-


pression has been repeatedly demonstrated with composted
municipal yard wastes containing significant quantities
of tree bark. If the compost is immature, the product may
not only be difficult to handle and have an offensive odor,
but may contain salts and metabolites toxic to plants. For
example, weed suppression has been demonstrated with
some types of immature composted materials which con-
tain and or produce organic acids with phytotoxic proper-
ties. Other studies have shown that soils amended with
different sources of composted municipal wastes were dis-
ease suppressive as long as they were relatively fresh (< 6
months), but as the composted municipal waste was aged,
disease suppressiveness was lost. In other Florida studies,
application of composted municipal wastes at rates up to
120 tons per acre have not been shown to have pesticidal
activity, but actually dramatically increased populations of
nematodes and other disease organisms such as Fusarium
and Phytopthora spp. Nematode population increases were
directly related to increases in plant growth and root sys-
tem size with amendment application rate.

Recent studies in Florida have been conducted to deter-
mine the extent to which increasing application rates of
a municipal solid composted waste affect the ability of
tomato plants to tolerate root infection by species of root-
knot nematode (Meloidogyne spp.) These studies showed
that in a sandy soil, poor in organic matter content (less
than 2%), tomato yields could be increased significantly
with soil amendments in both nematode free or nematode
infested soil. The impact of the root-knot nematode on
tomato yield was effectively constant however, suggesting
that application of the soil amendment did not enhance the
ability of tomato plants to tolerate infection by the root-
knot nematode. Much of the previous and ongoing research
in Florida also seems to indicate that the major effects of
soil amendments to crop yields appear to be less related to
nematode or soil pathogen control than to enhanced plant
nutrition and nutrient and water availability.

It is not clear at this time and preliminary stage of
university field research whether benefits to crop growth
after the initial crop following soil amendment applica-
tion can be expected. Recent studies showed no response
in second crop tomato yields (double crop) following
amendment application rates from 15 to 120 tons per acre.
Disappearance of nutrients and soil organic matter content
appears to be very rapid in the hot, moist soils of Florida.
Reapplication of the amendments may have to be made
on at least an annual basis to sustain crop growth and
yield benefits. In summary, the high rates of application
(tons/acre) and attendant costs required for crop response
and nematode control for many different types of organic
amendments, and the apparently rapid losses of the materi-
als in soil appears to restrict use of these materials primar-
ily to homeowner or small farm operations at this time.
However, with additional research and advances in appli-


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Vegetable Production Handbook


cation technology and use efficiency, use of soil amend-
ments may become an integral component of Florida crop
production systems.

Flooding
Extended periods of flooding suppresses nematode pop-
ulations. Alternating 2-to-3-week cycles of flooding and
drying are more effective than long, continuous flooding
cycles. At present, only limited areas within the state are
situated to take advantage of flooding as a viable means
of nematode control. Given the growing concern about
aquifer depletion, salt water intrusion, and water use inef-
ficiencies, it seems unlikely that Florida water management
officials will continue to permit flooding within these areas
in the future.

Soil Solarization
Soil solarization is a nonchemical technique in which
transparent polyethylene film is laid over moist raised beds
for a 6-to-12-week period to heat noncropped soils to tem-
peratures lethal to nematodes and other soil-borne patho-
gens. Soil temperatures are magnified due to the trapping
of incoming solar radiation under the clear, polyethylene
panels. To be effective, soils must be wetted and main-
tained at high soil moisture content to increase the suscep-
tibility (thermal sensitivity) of soil borne pests and thermal
conductivity of soil. Wet mulched soils increase soil tem-
peratures due primarily to the elimination of heat loss by
evaporation and upward heat convection, in addition to a
greenhouse effect by prohibiting dissipation of radiation
from the soil. At the end of the solarization period the clear
plastic is painted with a white or black latex paint to allow
continued use of the plastic as a mulch cover for the pro-
duction of vegetables on raised beds.

The most successful use of soil solarization appears to
occur in heavier (loamy to clay soils) rather than sandy
soils. Soils with poor water holding capacity and rapid
drainage can significantly inhibit heat transfer to deeper
soil horizons. Loss of pest control is directly correlated
with soil depth. The depth to which lethal temperature can
be achieved (6 to 8 inches) is also dependent on the inten-
sity and duration of sunlight and ambient temperature. At
present, the only time to consider soil solarization for pest
control is during our hot, summer and early fall months,
which fortunately are 'off-season' in most peninsular
Florida vegetable row crops. Unfortunately, our summers
are also our wettest period of the year with frequent after-
noon rain showers which have a cooling effect on the soil.

Many different pests have been suppressed and or con-
trolled by soil solarization, particularly within arid environ-
ments with intense sunshine, and limited cloud cover and
rainfall. Soil solarization can also be effective in a subtrop-
ical environment. Plant parasitic nematodes have generally
proved to be more difficult to control with soil solarization,


as have some weed pests such as crabgrass and purslane in
a central Florida study. The results of preliminary experi-
ments are also suggesting the potential for selection pres-
sures towards a buildup of heat tolerant individuals which
may serve to reduce soil solarization efficacy after repeated
use as a nematode control tactic.

In some studies, effective use of solarization for nema-
tode control has required an integrated systems approach,
coupling solarization with other chemical or nonchemical
approaches. For example, the combined use of soil solar-
ization with a nematicide has improved nematode control
and crop yield. In addition, use of virtually impermeable,
photo-selective plastic mulches may also complement low
dose fumigant treatments to reduce weed germination and
growth in the event of extended periods of cloud cover
occurring during the solarization regime. At this time, fur-
ther research is needed demonstrating soil solarization pest
control activity and consistency in the various geographical
regions of Florida where vegetable crops are grown.

Other Cultural Practices
Other cultural measures which reduce nematode prob-
lems include rapid destruction of the infested crop root
system following harvest. Fields which are disced as soon
as possible after the crop is harvested will not only prevent
further nematode population growth but subject existing
populations to dissipation by sun and wind. Use of nema-
tode free transplants is also recommended since direct
seeded plants are particularly susceptible since they are
vulnerable to injury for a longer duration, during an early,
but critical period of crop development. Since nematodes
can be carried in irrigation water that has drained from an
infested field, growers should avoid use of ditch or pond
waters for irrigation or spray mixtures. In most cases, a
combination of these management practices will substan-
tially reduce nematode population levels, but will rarely
bring them below economically damaging levels. This is
especially true of lands which are continuously planted to
susceptible crop varieties. In these cases some form of pes-
ticide assistance will still usually be necessary to improve
crop production.



CHEMICAL CONTROL

Nonfumigant Nematicides
All of the nonfumigant nematicides (Table 2) currently
registered for use are soil applied, with the exception of
Vydate, which can also be applied foliarly. They must be
incorporated with soil or carried by water into soil to be
effective. These compounds must be uniformly applied
to soil, targeting the application toward the future rooting
zone of the plant, where they will contact nematodes or, in
the case of systemics, in areas where they can be readily


Page 34







Chapter 4: Nematodes


absorbed. Placement within the top 2 to 4 inches of soil
should provide a zone of protection for seed germination,
transplant establishment, and protect initial growth of
plant roots from seeds or transplants. Studies performed in
Florida and elsewhere to evaluate non-fumigant nemati-
cides have not always been consistent, either for control-
ling intended pests or for obtaining consistent economic
returns to the grower, particularly when compared with
conventional preplant mulched fumigation with methyl
bromide or other broadspectrum fumigants. As the name
implies, they are specific to nematodes, requiring integrat-
ed use of other cultural or chemical pest control measures.
Many are reasonably mobile and are readily leached in our
sandy, low organic matter soils, thus requiring special con-
sideration to irrigation practices and management.

Nematode management must be viewed as a preplant
consideration because once root infection occurs and plant
damage becomes visible it is generally not possible to
resolve the problem completely so as to avoid potentially
significant yield losses. Recently, experiments were con-


ducted to evaluate the extent to which tomato plant growth
and yield could be 'rescued' from root-knot nematode via
early detection and treatment by post plant applications of
the nonfumigant nematicide, Vydate (Oxamyl). The results
of these experiments clearly showed that it was not pos-
sible to completely resolve the problem and avoid tomato
yield losses with post plant applications of Vydate. This
was particularly obvious in tomato yield responses with
foliar applications of Vydate attempting to resolve a soil-
borne problem. If an attempt is going to be made to rescue
the crop, the sooner the nematode problem is recognized
and soil applications of Vydate started, the greater the
improvement in tomato yields relative to plants maintained
nematode free.

Fumigant Nematicides
In Florida, use of broadspectrum fumigants (Table 2)
effectively reduces nematode populations and increases
vegetable crop yields, particularly when compared with
nonfumigant nematicides. Since these products must dif-
fuse through soil as gases to be effective, the most effec-


Table 2. Non-Fumigant Nematicides Registered for Vegetable Crop Use in Florida


Non-Fumigant Nematicides

Vegetable Mocap Counter Temik Vydate
Beans *
Carrots *
Celery
Corn, sweet *
Cabbage *
Brussels sprouts
Cucumber *
Melons *
Squash *
Okra
Potatoes
Potatoes, sweet *
Eggplant
Tomato *
Pepper *
Strawberry

This information was compiled as a quick reference for the commercial Florida vegetable grower The mentioning of a chemical or proprietary product in this publication does
not constitute a written recommendation or an endorsement for its use by the University of Florida, Institute of Food and Agricultural Sciences, and does not imply its approv-
al to the exclusion of other products or practices that may be suitable. Products mentioned in this publication are subject to changing State and Federal rules, regulations and
restrictions. Additional products may become available or approved for use. Growers have the final responsibility to guarantee that each product is used in a manner consistent
with its label.


Page 35







Vegetable Production Handbook


tive fumigations occur when the soil is well drained,
in seedbed condition, and at temperatures above 60F.
Fumigant treatments are most effective in controlling root-
knot nematode when residues of the previous crop are
either removed or allowed to decay. When plant materials
have not been allowed to decay, fumigation treatments
may decrease but not eliminate populations of root-knot
nematodes in soil. Crop residues infested with root-
knot nematode may also increase soil populations to the
extent that significantly higher rates of application may
be required to achieve nematode control. To avoid these
problems, growers are advised to plan crop destruction and
soil cultivation practices well in advance of fumigation to
insure decomposition of plant materials before attempting
to treat the soil.

For over 40 years, Florida producers of many high
value fruit and vegetable crops have relied upon methyl
bromide soil fumigation to resolve their soilborne pest and
disease. In 1991, methyl bromide was detected in signifi-
cant concentration within the earth's stratosphere. In sub-
sequent studies, it was shown to catalyze the destruction
of ozone, and determined to be a significant contributor to
stratospheric ozone depletion, thinning, and the creation of
an ozone hole over Antarctica. After being classified as a
Class I ozone depleting chemical in 1993, methyl bromide
was mandated by the Clean Air Act of 1990 for eventual
phase-out from production and agricultural use. After more
than a decade long regulatory struggle with numerous
reprieves, the final phase-out date for methyl bromide pro-
duction, importation, and use within the U.S. proceeded as
scheduled to January 1, 2005. As a grandfather clause, it
is still possible to continue to use methyl bromide supplies
produced prior to January 1, 2005, but only on the four
currently defined 'critical use exempted' crops of tomato,
pepper, eggplant and strawberry.

For tomato, pepper, eggplant and strawberry, contin-
ued post phase-out availability is now driven by a more
complex process involving the use of both remaining, pre
2005 produced commercial stocks of methyl bromide, as
well as those derived from new production made available
only through annual award of a Critical Use Exemption
(CUE). The CUE is a rather complicated, national and
international regulatory process. Simplistically described,
the CUE represents a U.S.A. request for continued use
of methyl bromide that is submitted to and approved by
an international United Nations and Montreal Protocol
authority, which substantiates the need for continuing use
of methyl bromide for crops and farming enterprises in
which "no technically or economically feasible alterna-
tive to methyl bromide is shown to exist". We have been
fortunate in that approved CUE levels for new production
of methyl bromide have been awarded for calendar years
2005 through 2010. A CUE request for continued use of
methyl bromide for 2011 has also been submitted for con-
sideration and approval. Each year the approved level of


new production combined with supply of existing stocks
is reduced which at some point of reduced availability will
ultimately force Florida growers to transition to alterna-
tives strategies in the following year or two. Further infor-
mation regarding the methyl bromide CUE process, dimin-
ishing supply and transition strategy to alternatives can be
found in a subsequent chapter of this production guide.

Ultimately, the loss of methyl bromide in the U.S.A
will create a void for Florida growers in the chemical
arsenal currently used for soilborne pest and disease con-
trol. This fact is made quite clear from a decade review
of recent field research trials conducted in Florida which
show that no single, equivalent replacement (chemical or
nonchemical) currently exists which exactly matches the
broadspectrum efficacy of methyl bromide. In preparation
for the ultimate phase-out and loss of methyl bromide, uni-
versity research programs within Florida have continued
to identify and evaluate more robust strategies which mini-
mize cropping system impacts, accounting for a diverse
range of pest pressures and environmental conditions.
Based on summary and comparison of methyl bromide
alternative chemical trial results in Florida since 1994,
Telone (1,3-Dichloropropene) plus Chloropicrin) applied
either separately or coformulated as Telone C35 (1.3-D
plus 35% Chloropicrin) or Pic-Clor 60 (1,3-D plus 59%
Chloropicrin) in combination with a separately applied
herbicidal compound or MITC generating fumigant for
weed control, has been identified as the best chemical
alternative replacement for methyl bromide for some veg-
etable row crops such as strawberry and tomato. In straw-
berry, use of formulations of 1,3-D with higher proportion-
ate levels and rates of application of chloropicrin have not
consistently resulted in effective sting nematode control
when compared with Telone C35 or Telone Inline.

This has also been repeatedly demonstrated in large
scale, commercial field trials around the state. In these
studies, use of Telone and Chloropicrin in combination
with a herbicide treatment, including mini-coulter applica-
tion of metam sodium or potassium to the bed top prior
to installing the plastic mulch, generally resulted in near
equivalent yields to that of methyl bromide. With repeated
long term use, or under conditions of high pest pres-
sures (weeds, nematodes, disease), other IPM practices
might also be required and combined to achieve adequate
control and economic crop productivity. For example,
prebed treatments of Telone C35 (35 gal/A) or Telone II
(12 gal/A) followed by an additional in-bed application
of chloropicrin (150 lb/A) followed by metam sodium
application (75 gal/A) to the bed top has been required for
effective weed and disease control in pepper. In combina-
tion with Telone, Telone C35 or Chloropicrin, growers are
also encouraged to use only a high barrier, metalized, or
virtually impermeable mulch film (VIF) with measured
transmissivity to methyl bromide of less than 0.2 grams
per meter square per hour. With use of the more imperme-


Page 36







Chapter 4: Nematodes


able mulches, fumigant rates have been reduced as much
as 25 to 40% from maximum labeled application rates
without loss of pest control or crop yield in a number of
studies. Given the potential variability, growers should
consider their own small scale field trials to determine
the degree to which rates reductions of the different fumi-
gants with high barrier mulches is possible. Due to use
restrictions for all Telone products in Dade County, either
metham sodium or metham potassium at 75 and 60 gallons
per treated acre respectively, in combination with shank
injections of chloropicrin (150 pound per treated acre) and
appropriate herbicide(s) are currently defined as the best
alternatives to methyl bromide.

Major changes in the federal label for Telone products
has recently occurred and personnel protective equipment
(PPE) and buffer zone requirements have been greatly
reduced, particularly for field workers with no liquid con-
tact potential. For example, rubber boots, gloves, coveralls,
and full-face respirators are no longer mandatory PPE
requirements. For in-bed Telone applications, the require-
ment now only requires the use of a half-face respirator
and safety glasses by field workers. For other applications
(e.g., prebed treatments which are applied to the flat prior
to bedding), PPE requirements are further reduced and
do not require a half-face respirator. It is also expected
however, that EPA will soon impose new product label
constraints for many if not all of the other alternative fumi-
gants currently undergoing registration by the U.S. EPA.
These new label constraints are likely to include reduction
of maximum rates of fumigant application per treated acre,
requirements for additional pesticide and respirator train-
ing, fit testing, medical certification to ensure field workers
abilities to wear respirators, and expanded buffer zones
between agriculturally treated lands and urban areas. In all
cases, the grower has the final responsibility to insure that
the label is consulted and that each product is used legally
according to the label.

As with any new technology, prebed applications of
Telone or Telone C35 by growers will require some new
field equipment and changes in application procedure
and timing. Deep placement of Telone C-35 is not only
a requirement of the pesticide label but is essential for
prolonged fumigant retention in soil. Unfortunately, deep
injection of prebed applications of Telone C-35 to a depth
of 10 to 12 inches can be difficult to achieve because of
the presence of a compacted traffic layer in most fields. To
enhance treatment efficacy, growers should consider tillage
operations which destroy the traffic pan to ensure fumigant
diffusion within the bed and soil profile with deep place-
ment of Telone. Federal and state regulations currently
limit the application of any Telone containing product
within 100 feet of any occupied structure, dwelling, or
drinking water well. Unavoidably, some uncontrollable
environmental factors such as temperature and rainfall can
affect the performance of fumigant treatment and plant-


back scheduling. Growers must therefore plan accordingly
to account for any unforeseen delays in fumigant dissipa-
tion from soil and to avoid potential phytotoxic impact to
crops.

All of the fumigants are phytotoxic to plants and as a
precautionary measure should be applied at least 3 weeks
before crops are planted. When applications are made in
the spring during periods of low soil temperature, these
products can remain in the soil for an extended period, thus
delaying planting or possibly causing phytotoxicity to a
newly planted crop. Field observations also suggest rainfall
or irrigation which saturates the soil after treatment tends
to retain phytotoxic residues for longer periods, particu-
larly in deeper soil layers.



SUMMARY

In summary, nematode control measures can be con-
veniently divided into two major categories: cultural and
chemical. None of these measures should be relied upon
exclusively for nematode management. Rather, when prac-
tical and economics permit, each management procedure
should be considered for use in conjunction with all other
available measures for nematode control and used in an
integrated program of nematode management.

In addition, to nematodes, many other pests can cause
crop damage and yield losses which further enforces the
development of an overall, Integrated Pest Management
(IPM) program, utilizing all available chemical and
nonchemical means of reducing pest populations to sub-
economic levels. An IPM approach further requires that
growers attempt to monitor or scout fields for pest densi-
ties at critical periods of crop growth.


Page 37







Page 38 Vegetable Production Handbook


Table 3. Broadspectrum Fumigant Nematicides Registered for Vegetable Crop Use in Florida

Formulation
Methyl Bromide3
To Chloropicrin2 OTHER FUMIGANTS
Pic-Clor1 Telone1
60 C35
0 0 Methyl2 Metam2 Metam2 Pic-Clor1 Telone1 Telone1 Telone1
Crop/Use 50 100 Iodide Sodium Potassium 60EC II C17 Inline
Asparagus *
Broccoli *
Cauliflower *
Cucumber *
Eggplant *
Muskmelon *
Onions (bulb) *
Onions *
Peppers *
Tomato *
Sweet potato *
Vegetable *
Strawberry *
Plant Bed *
Seed Bed *******
1 Crop recommendations for Pic-Clor 60, Pic-Clor 60EC, Telone II, Telone C17, Telone C35, or Telone Inline do not apply to the Homestead, Dade County production region of
south Florida where soil types and water tables currently prohibit product use. Other supplementary labeling with additional county or soil and use restrictions may apply.
2 Currently completing EPA Fumigant Reregistration review, with significant label changes anticipated early in 2010 to maximum application rate, high barrier impermeable mulch
films, personal protective equipment, Buffer Zone, and other new restrictions and requirements.
3 A critical use exemption (CUE) for continuing use of methyl bromide for tomato, pepper, eggplant and strawberry has been awarded for calendar year 2010. Specific certified
uses and labeling requirements for existing stocks and CUE acquired methyl bromide must be satisfied prior to grower purchase and use in these crops. Formulation availability
is subject to change.
This information was compiled as a quick reference for the commercial Florida vegetable grower The mentioning of a chemical or proprietary product in this publication does
not constitute a written recommendation or an endorsement for its use by the University of Florida, Institute of Food and Agricultural Sciences, and does not imply its approval
to the exclusion of other products or practices that may be suitable. Products mentioned in this publication are subject to changing State and Federal rules, regulations and
restrictions. Additional products may become available or approved for use. Growers have the final responsibility to guarantee that each product is used in a manner consistent
with its label.






UF UNIVERSITY of
UFFLORIDA
IFAS Extension
2010-2011


Weed Management

W.M. Stall and A.W. MacRae


CROP GROUPS

The Environmental Protection Agency is authorized to
establish tolerances for pesticide residues in raw agricul-
tural commodities under section 408 of the Federal Food,
Drug and Cosmetic Act (FFDCA) (21 USC 34a). Crop
grouping regulations currently in effect enable establish-
ment of tolerances for a group of crops based on residue
data for certain crops that are representative. In other
words, establishing tolerances for three specified crops in
a group could also establish tolerances for pesticide use
on the remainder of the commodities of that group, which
may be up to 19 separate commodities.

Commodity groups or subgroups are specified in the
Federal Register. A proposed rule on the Revision of Crop
Groups (40 CFR 180) is under consideration at this time.
To avoid confusion on specific commodities or groups
that may be listed on labels, a brief summary is provided
below:

Beans and Peas
If the term bean appears on the label, the material may
be applied to both Phaseolus and Vigna types of beans.
The Phaseolus beans include adzuki bean, field bean, kid-
ney bean, lima bean, moth bean, mung bean, pinto bean,
rice bean, runner bean, snap bean, tepary bean, urd bean,
and wax bean. The Vigna beans include southernpea, cow-
pea, asparagus bean, catiang, Chinese long bean, and yard
long bean. If the term beans is on the label, then the mate-
rial may be applied to southernpeas as well as snap beans.
However, if the term green bean appears, the material may
be applied to only the green color snap bean, and not the
wax types. Peas do not include southernpeas but include
all Pisum species including English pea, edible-pod pea,
snowpea, sugar pea, dwarf pea, and Cajanus cajan, the
pigeon pea.

Brassica (cole) Leafy Vegetables
The Brassica leafy vegetable group includes broccoli,
Brussels sprouts, cabbage, cauliflower, Chinese broccoli,
broccoli raab rapinii), Chinese cabbage (bok choy, napa),
Chinese mustard cabbage (gai choy), collards, kale, kohl-
rabi, mustard greens, rape greens and turnip greens.


If the label states brassica leafy vegetables, as does the
label for Dacthal, then it may be applied to all of the com-
modities in the group. If the label states only a specific
commodity, such as cabbage, then only that commodity
may be treated.

Beyond that, in instances where the tolerance is on cab-
bage, then it also includes the tight headed Chinese cab-
bage. Therefore, if the label states cabbage (tight headed),
it may be applied to cabbage and the napa types of Chinese
cabbage. The michihili types are classified as loose headed,
as is bok choy.

Bulb Crops
Bulb crops include all of the Allium species except
chives. Bulb crops include onions (dry and green), leek,
garlic and shallot.

Cucurbit Crops
Cucurbit crops include cucumber, squash, watermelon
and muskmelon along with commodities falling under
these groups. Melons is a general term which designates
muskmelon, including hybrids and/or varieties of Cucumis
melo, and watermelon, including hybrids and/or varieties
of Citrullus spp.

The term Muskmelons includes hybrids and/or varieties
of Cucumis melo (including true cantaloupes, cantaloupe,
casaba, Santa Claus melon, crenshaw melon, honeydew
melon, honey balls, Persian melon, golden pershaw melon,
mango melon, pineapple melon, and snake melon).

Summer squash includes fruits of the gourd
(Cucurbitaceae) family that are consumed when immature;
100% of the fruit are edible either cooked or raw; cannot
be stored once picked; have soft rinds which are easily
penetrated; and if seeds were harvested, they would not
germinate. Summer squash includes Cucurbita pepo (i.e.
crookneck squash, straightneck squash, scallop squash, and
vegetable marrow); Lagenaria spp (i.e. hyotan, cucuzza);
Luffa spp (i.e. hechima, Chinese okra); Momordica spp
(i.e. bitter melon, balsam pear, balsam apple, Chinese
cucumber); and other varieties and/or hybrids of these spe-
cies.


Page 39


Chapter 5.







Vegetable Production Handbook


Lettuce
Head lettuce only applies to crisp head varieties of let-
tuce. Leaf lettuce applies to all leaf lettuce types, includ-
ing leaf lettuce, cos (Romaine) and the butterhead variet-
ies. The term Lettuce includes head and leaf lettuce, i.e.,
all types except endive and escarole. Endive is a separate
tolerance group and includes endive and/or escarole.



WEED MANAGEMENT

Weeds reduce yield and quality of vegetables through
direct competition for light, moisture and nutrients as well
as by interference with harvest operations.

Early season competition is most critical and a major
emphasis on control should be made during this period.
Common amaranth reduces yields of lettuce, watermelon
and muskmelon at least 20% if allowed to compete with
these crops for only the first 3 weeks of growth. Weeds can
be controlled, but this requires good management practices
in all phases of production. Because there are many kinds
of weeds, with much variation in growth habit, they obvi-
ously cannot be managed by a single method.

The incorporation of several of the following manage-
ment practices into vegetable production practices increas-
es the effectiveness for controlling weeds.

Crop Competition
An often overlooked tool in reducing weed competition
is to establish a good crop stand, in which plants emerge
and rapidly shade the ground. The plant that emerges first
and grows the most rapidly is the plant that will have the
competitive advantage. Utilization of good production
management practices such as fertility, well-adapted vari-
eties, proper water control (irrigation and drainage), and
establishment of adequate plant populations is very helpful
in reducing weed competition. Everything possible should
be done to insure that vegetables, not weeds, have the
competitive advantage.

Crop Rotation
If the same crop is planted in the same field year after
year, there usually will be some weed or weeds favored by
the cultural practices and herbicides used on that crop.

By rotating to other crops, the cultural practices and
herbicide program are changed. This often reduces the
population of specific weeds which were tolerant in the
previous cropping rotation. Care should be taken, however,
in not replanting vegetables back into soil treated with a
non-registered herbicide. Crop injury as well as vegetables
containing illegal residues may result. Check the labels for
plant back limitations before application and planting rota-
tional crops.


Mechanical Control
Mechanical control includes field preparation by plow-
ing or discing, cultivation, mowing, hoeing and hand pull-
ing of weeds. Mechanical control practices are among the
oldest of weed management techniques.

Weed control is a primary reason for preparing land for
crops planted in rows. Seedbed preparation by plowing or
discing exposes many weed seeds to variations in light,
temperature, and moisture. For some weeds, this process
breaks weed-seed dormancy, leading to early season con-
trol with herbicides or additional cultivation.

Cultivate only deep enough in the row to achieve weed
control; deep cultivation may prune crop roots, bring weed
seeds to the surface, and disturb the soil previously treated
with a herbicide. Follow the same precautions between
rows.

When weeds can be controlled without cultivation, there
is no advantage to cultivating. In fact, there may be disad-
vantages such as drying out the soil surface, bringing weed
seeds to the surface, and disturbing the root system of the
crop.

Mulching
The use of polyethylene mulch increases yield and earli-
ness of vegetables. The proper injection of fumigants under
the mulch will control nematodes, soil insects, soil-borne
diseases and weed seeds. Mulches act as a barrier to the
growth of many weeds. Nutsedge, however, is one weed
that can and will grow through the mulch.

Prevention
Preventing weeds from infesting or reinfesting a field
should always be considered. Weed seed may enter a field
in a number of ways. It may be distributed by wind, water,
machinery, in cover crop seed and other ways. Fence rows
and ditch banks are often neglected when controlling
weeds in the crop. Seed produced in these areas may move
into the field. Weeds in these areas can also harbor insects
and diseases (especially viruses) that may move onto the
crop.

It is also important to clean equipment before enter-
ing fields or when moving from a field with a high weed
infestation to a relatively clean field. Nutsedge tubers
especially are moved easily on discs, cultivators and other
equipment.

Herbicides
Properly selected herbicides are effective tools for
weed control. Herbicides may be classified several ways,
depending on how they are applied and their mode of
action in or on the plant. Generally, herbicides are either
soil applied or foliage applied. They may be selective or


Page 40







Chapter 5: Weed Management


non-selective, and they may be either contact or translo-
cated through the plant. For example, paraquat is a foliage
applied, contact, non-selective herbicide, while atrazine
usually is described as a soil-applied, translocated, selec-
tive herbicide.

Foliage-applied herbicides may be applied to leaves,
stems and shoots of plants. Herbicides that kill only those
parts of the plants which the spray touches are contact her-
bicides. Those herbicides that are taken into the plant and
moved throughout the plant are translocated herbicides.
Paraquat is a contact herbicide while glyphosate (Roundup)
or sethoxydim (Poast) are translocated herbicides.

For foliage-applied herbicides to be effective, they must
enter the plant. Good coverage is very important. Most
foliage applied herbicides either require the addition of a
specified surfactant or a specified formulation to be used
for best control.

Soil-applied herbicides are either applied to the surface
or incorporated. Surface-applied herbicides require rainfall
or irrigation shortly after application for best results. Lack
of moisture often results in poor weed control.

Incorporated herbicides are not dependent on rainfall
or irrigation and have generally given more consistent and
wider-spectrum control. They do, however, require more
time and equipment for incorporation.

Herbicides which specify incorporation into the soil
improve the contact of the herbicide with the weed seed
and/or minimize the loss of the herbicide by volatilization
or photodecomposition. Some herbicides, if not incorpo-
rated, may be lost from the soil surface.

Although most soil-applied herbicides must be moved
into the soil to be effective, the depth of incorporation into
the soil can be used to achieve selectivity. For example, if
a crop seed is planted 2 inches deep in the soil and the her-
bicide is incorporated by irrigation only in the top 1 inch
where most of the problem weed seeds are found, the crop


roots will not come in contact with the herbicide. If too
much irrigation or rain moves the herbicide down into the
crop seed zone or if the herbicide is incorporated mechani-
cally too deep, crop injury may ensue.



ESTIMATED EFFECTIVENESS OF RECOMMENDED
HERBICIDES ON SELECTED
COMMON WEEDS IN FLORIDA VEGETABLES

Identifying the weed problems and selecting appropriate
control methods are essential steps in designing or modify-
ing a weed control program. Knowing the weed species
that infest the fields is also important in selecting the cor-
rect herbicide that is effective for specific weed problems.
Generally, for preplant and preemergence applications, the
weed problem must be anticipated since weeds have not
emerged at the time of application. This can be done by
observing the field in the previous season and recording
those weeds which are present and in what areas of the
field they occur. These weed maps can be very useful the
next season in refreshing your memory and making deci-
sions on which herbicides to purchase. Once weed prob-
lems have been determined, the following tables can be
helpful in determining the herbicide which is most effec-
tive for control of those weeds.

Table 1 and Table 2, estimating the effectiveness of
control of certain herbicides, were developed from research
data, herbicide labels, and the experience of research and
extension workers in Florida.

The estimated effectiveness is based on recommended
rates for vegetables in Florida and application procedures
as specified by the label. Herbicide effectiveness may vary
due to soil type, environmental conditions (rainfall, tem-
peratures, etc.), method and time of application, as well
as size of weeds. Consult the herbicide label for specific
information relating to crop use and expected response of
the herbicide in specific soil types.


Page 41







Vegetable Production Handbook


Table 1. Estimated effectiveness of herbicides on selected broadleaf weed in vegetables.


a,
a, a,


L E CIE C
'- .0 5M W ED
Cu ~c cc cc Cu C u =L*= =
E a, U cc cc t3 E cc El D
Herbicide E CD S C. a a: a- Cu M Cu o
PREPLANT INCORPORATED


F-G P-F G
F-G P F-C
F-G P G
G P G-E
G P G
F P F
G-E E
E G E
G-E P G


Command
Dacthal
Devrinol
Dual
Eptam
Prefar
Pursuit
Sencor
Treflan


Alanap
Atrazine
Callesto
Caparol
Chateau
Command
Curbit
Dacthal
Devrinol
Dual
Goal
Kerb
Lorox
Matrix
Prowl
Pursuit
*Sandea
Sencor


- G
F F
P P G-E
G F-G G-E
G P G-E
P P E
E E F
G G-E G
F-G P E
PREEMERGENCE
G F G
G-E G-E E


- F-G
G G-E
- G
P E
F F
P G
F G
G G
- G
G E
E -
P G
P F
- F
G G


G-E E
G G
P G-E G
F-G F
G G
F-G F
E E
G E G
P G-E E


- E G
E E E
G -
F-G G-E
G-E G-E
G E
P G-E E
- G G
P G G
- F P
G E E
E G-E
E E
E E
P E G
G-E G-E
G G
G E G


F-G P
P F
P
F P G
F F G
P P P
G P G
G G G
P P P


F P G
E F-G G-E
G NC
F-G
G-E G G
F P
P P P
P F
P
F P G
G F G


G F


G-E F
E G-E
G-E F
G-E -
G-E G-E
F-G P
G P
F-G P
F P
G F
E E
F-G -
G F
G-E G-E
G-E P
G-E G-E
G-E G
G F


Page 42







Chapter 5: Weed Management


Table 1. Continued.


Cc
Cu CE

W cc
Aim E G E G G G E G G E E G G-E






Atrazine G-E F E G P G-E F-G G F-G G F F F-G
Callisto E G-E G G-E F G G G N
Chateau E G G F-P F-G F-G F-G G F-G F-G F-G



Cobra E G-E E E G-E F-G G G-E E G F-G G
c E t E cc W GL
Herbicide E G a: M F- M F- = =











Diquat E G E E G-E G E E G F-G G G G G
Enquik E G E E E G G F-G G F G G G G

FusiladeDX N N N N N N N N N N N N N N
Gramoxone E G E E G-E G P E G F-G F G G G
Impact G-E G-E F-G G G E G-E G
Laudis E E G G-E N F G G-E F N
Lorox E G G G E E F-G G G G
Matrix G G-E G G G G P G P G
Past N N N N N N N N N N N N N N

Pursuit E G G G F F-G P-F G G G P
Select N N N N N N N N N N N N N N
*Sandea G G F P P F G G -
Sencor E G G F G G P G F-G P P F-G F F

E = 90-100% N = no control G = 80-90% -= no data F = 60-80% P = below 60% *Poor on Livid Amaranth


Page 43







Page 44 Vegetable Production Handbook


Table 2. Estimated effectiveness of herbicides on selected grasses and sedges in vegetables.


Grasses Sedges




H X0





cCallisto F-G G G F-G N N





Chateau G G G G N N N
Command E G-E E E E G-E P P P
Dacthal G G F G G F P P P
Devrinol E E E E E G-E P F F

Dual G G-E E E E G G P-F G G-E
Eptam E E G E E G-E G-E G E
Prefar G G G G G-E F-G P P
Pursuit F P F F F P-F P F-G G E
Sandea N N N N N N N G-F F-G G

Sencor G F-G G G-E G-E F-G P P
Treflan E G G-E E E G P P P

PREEMERGENCE
Alanap P P F F P P P P P
Atrazine F P F-G F F P P P P P
Caparol F-G F-G F-G G F-G F P P P

Command E E E E E E P P P
Curbit E G-E E E E G-E G P P P
Dacthal F-G F-G F G G F P P P
Devrinol E E E E E G-E P-F F F-G
Dual G G-E E E E G-E G P-F F-G E
Goal E E G E E G-E G-EP F G
Kerb G-E P G G-E G-E F-G P P P

Lorox F-G G G G F-G F F F
Matrix P P P P P P P PP P
Prowl E E E E E G-E E P P P
Pursuit F P F F F P-F P G G-E E
Sencor G F G G G-E P P P P P
Sencor F F G G G-E P P P P P







Page 45


Chapter 5: Weed Management


Table 2. Continued.


Herbicide


Grasses


C0
C0
Cu
C)
.0
Cu
C-,


CD

CD
CM
01
C0
0
cs


Sedges


POSTEMERGENCE

Aim P P P P P P P P P P

Atrazine F-G F F F F F F P P P

Basagran P P P P P P P P-F F-G G-E

Callisto G-F F-G F-G N N N

Cobra N N N N N N N N N N

*Diquat E-G G E G-E G-E G G F-G F-G G

Enquik P-F P-F P-F P-F P-F P-F F F F

Fusilade E E E E E E E P P P

*Gramoxone E E E E E E E F-G F-G G

Impact G G G N N N

Laudis G G F-G G G-E N N N

Lorox G F-G G G G G G F F F-G

Matrix P P P P P P P P P

Poast E G-E E E G E E N N N

Pursuit F P P-F PR F P-F P G-E G-E G-E

Select E G-E G-E G-E E E E N N N

Sandea N N N N N N N E E E

Sencor F P P-F F F-G P P P P P

E = 90-100% N= no control G = 80-90% = no data F = 60-80% P= below 60% Initial burndown with sedges and other perennial weed can be complete but regrowth occurs.






Page 46 is
missing from
the original
document






UF UNIVERSITY of
UF FLORIDA
IFAS Extension
2010-2011


Alternatives to Methyl Bromide Soil Fumigation

for Florida Vegetable Production

J. W. Noling, D. A. Botts, and A. W. MacRae


In 1991, climatic studies of historic concentrations of
methyl bromide captured in polar ice showed increasing
amounts of the compound over the past several decades. In
subsequent studies, it was shown to catalyze the destruc-
tion of ozone, and determined to be a significant contribu-
tor to stratospheric ozone depletion, thinning, and the cre-
ation of an ozone hole over Antarctica. After being classi-
fied as a Class I ozone depleting chemical in 1993, methyl
bromide was mandated by the Clean Air Act of 1990 for
eventual phaseout from production and agricultural use.
After a 13-year-long regulatory process with numerous
shifts to the schedule for final regulatory action, the final
phase-out date for methyl bromide production and impor-
tation, for use within the U.S. proceeded as scheduled on
January 1, 2005. As with other ozone depleting substances
regulated under the Montreal Protocol on Ozone Depleting
Substances and the U. S. Clean Air Act, supplies of mate-
rials manufactured and imported prior to the scheduled
phase out continue to be legal to use as approved for only
specifically exempted crops.

In tomato, pepper, eggplant, and strawberry, continued
post phase-out availability is now driven by a more com-
plex process involving the use of both remaining com-
mercial stocks of methyl bromide, as well as those from
other new supplies made available only through award of
a Critical Use Exemption (CUE). The CUE process is a
complicated, national and international regulatory driven
procedure. Simplistically described, the CUE is a process
of documenting the need for continued use as described
by the collective research efforts of grower organiza-
tions, University of Florida IFAS research and extension
faculty, as well as many other state and federal agencies.
It culminates in a final document compiled by the U. S.
Government of all such petitions nationwide that is submit-
ted for review and approval by the Parties to the Montreal
Protocol. The criterion for approval is the need for continu-
ing use of methyl bromide for crops and farming enter-
prises in which "no technically or economically feasible
alternative to methyl bromide is shown to exist".

Based on CUE petitions developed and submitted by
the Florida Fruit & Vegetable Association (FFVA), and
endorsed and supported by EPA, USDA, and the United
States State Department, a critical use exemption for con-


tinuing use of methyl bromide for tomato, pepper, eggplant
and strawberry has been awarded for calendar years 2005
through 2010. CUE's for these crops for 2011 are current-
ly in the review and approval process at the international
level. The reference baseline used for regulatory compari-
son is the use during the 1991 calendar year. Total Critical
Use Exemptions at the national level are reported as per-
centages of this 1991 baseline. With each additional year
of CUE submission, the amount of new methyl bromide
production awarded or allowed is generally less than the
amount of methyl bromide awarded the previous year and,
more importantly, of the amount formally requested by the
U. S. Government in its Critical Use Nomination (Figure
1). Because of the diminishing level of existing commer-
cial stocks, and significantly reduced allowances for the
production of new product, shortages in methyl bromide
supply are becoming more apparent, and are fully expected
to become much more severe than in previous years as we
progress through the 2009 2010 cropping season.

Florida growers, who have continued to rely on exist-
ing and internationally approved CUE supplies of methyl
bromide, painfully recognize an increase in price, a future
of diminishing supply, and the limits to which methyl
bromide use rates can be reduced without loss of pesti-
cidal efficacy and crop yield. Local competitive pressures




I - .


,.2
--- \

Sc. \ -

2 2Me 20o0 200* fU 2 10
YEAR
Figure 1. Statistical projection of forced rates of adoption of alter-
natives based on the CUE approved amounts of "new"
methyl bromide production and consumption. The pro-
jection is based on assumptions of minimal "available
stocks", 1991 use characteristics and 2005 base crop
acreages.


Page 47


Chapter 6.







Vegetable Production Handbook


have led to Florida growers being reluctant to transition to
new integrated pest management strategies which include
co-application of different fumigants and herbicides, and
adoption of other alternative cultural practices to achieve
pest control efficacy and crop yield response similar to that
of methyl bromide.

Transition to the alternatives also suggest that grow-
ers will have to implement other significant changes to
current practices, including integration of new fumigant
distribution and soil injection technologies, and new till-
age and irrigation practices to enhance the performance
of alternatives and reduce potential fumigant emissions
from treated fields. With the EPA fumigant reregistration
process nearing completion, all of the currently registered
fumigant alternatives will have new proposed restrictions
which will further limit their use (i.e., reduced rates and
acreages treated per day, expanded buffer zones, worker
exposure risks). The new regulatory criteria for fumigant
use are designed to strongly encourage emission reduction
strategies which include high barrier (more gas imperme-
able) plastic mulches to reduce overall field application
rates and soil emissions of fumigant gases. Grower tran-
sition to these new IPM methods will be incrementally
driven by methyl bromide supply, and by many other avail-
able products on-farm, within field, pest, soil, crop, and
economic considerations. The primary objectives for any
methyl bromide transition strategy are to manage adoption
of alternatives over time, to minimize changes to the crop
production system, and define and remove performance
inconsistency of alternatives.

Imperatives for Transition
As Figure 1 illustrates, with each new year the amount
of methyl bromide new production approved for CUEs is
generally less than the amount of methyl bromide approved
the previous year. Up until 2009, it was widely believed
that these reductions in new production had not signifi-
cantly impacted methyl bromide availability to Florida
growers because of the buffering capacity of the previously
produced, existing supplies. Late in 2008 it became appar-
ent that the distribution of those available stocks resulted
in shortages of methyl bromide in the regional distribu-
tion system. As existing commercial stocks are depleted
and international approval for production of new product
decreases, severe shortages in methyl bromide supply
were beginning to be observed in late Fall 2006 and again
in 2008 and will continue to amplify with each cropping
season through 2010 and beyond. Approved CUE levels
for new production and consumption in 2010 are cur-
rently projected at 10.8% of the 1991 baseline level, an
increase from the previous year because of the significant
drawdown which occurred in 2008-09. With an apparent
regulatory focus to exhaust existing stockpiles in 2009 and
vegetable acreage unchanged, even a 50% methyl bromide
use rate reduction with high barrier, methyl bromide imper-
meable mulches suggests that there will not be adequate


supplies to meet projected needs in Florida during 2010.
To sustain availability, methyl bromide distributors are also
currently only providing formulations with increased chlo-
ropicrin content, primarily a formulation of 50% methyl
bromide and 50% chloropicrin. As this potential scenario
becomes reality, Florida growers will ultimately be forced
to transition to alternatives strategies for crops currently
dependent upon methyl bromide, particularly when product
pricing is expected to reach as much as $6.00 per pound.

Clearly the time has arrived to document and describe a
process for an orderly transition and implementation of the
alternatives. Many different timelines and acreage com-
mitments to alternatives can be envisioned. A seamless
transition would commit new acreage to alternatives at a
rate equal to or greater than the rate that methyl bromide
annually decreases in supply. Figure 1 depicts a timeline
for orderly transition to alternatives as an inverse function
of CUE approved levels of new methyl bromide production.
This projected transition timeline would indicate a need for
Florida growers to commit as much as 40% of their acreage
to alternatives by the end of calendar year 2006, and to 70%
and 90% by the end of 2007 and 2010, respectively. In real-
ity, this has not occurred and growers are only slowly adopt-
ing alternatives. The dashed line of Figure 1 represents what
appears to be the more realistic and accurate scenario in
which expedited grower transition to methyl alternatives is
predominately driven by lingering grower preference, higher
unit price, and reduced availability of methyl bromide in a
desirable formulation within the marketplace.

Beginning the transition allows growers to strategize
an on-farm implementation plan to minimize production
problems, gain valuable worker experience with the alter-
natives, and to preserve methyl bromide use for their most
difficult pest management fields. Transition to the multi-
chemical combination treatments will be more difficult
and less forgiving than that of methyl bromide. Given the
steepness of the learning curve for use of the alternatives.
Florida growers currently dependent upon methyl bromide
are strongly encouraged to begin the commitment and tran-
sition to alternatives without further delay.

Alternative Fumigant Chemicals
Since 1993, many different alternative soil fumigants
have been evaluated in field trials to characterize pest con-
trol efficacy and crop yield response (Table 1). The results
of these research trials have provided basis for overall
generalization of pesticidal activity for each of the alterna-
tive fumigant chemicals. As a standard for comparison, this
research has repeatedly demonstrated methyl bromide to
be very effective against a wide range of soilborne pests
including nematodes, diseases, and weeds. Methyl iodide,
a recent entry to registered fumigants in Florida, has shown
similar broadspectrum pest control activity as that of meth-
yl bromide. Chloropicrin has proved very effective against
diseases but seldom nematodes or weeds. Telone (1,


Page 48







Chapter 6: Alternatives to Methyl Bromide Soil Fumigation for Florida Vegetable Production


3-dichloropropene) is an excellent nematicide but gener-
ally performs poorly against weeds and diseases. Bacterial
pathogens have not been satisfactorily controlled by any of
the fumigants. Metam sodium and metam potassium can
provide good control of weeds when placed properly in the
bed, however research to evaluate modification of rate,
placement, and improved application technology have not
resolved all problems of inconsistent pest control.

Much of the current field research continues to focus
on evaluations of chloropicrin co-applied with additional
fumigants. In this co-application approach, chloropicrin
has clearly been shown to be the integral, foundation com-
ponent of any alternative chemical approach to replace
methyl bromide. Of the chloropicrin combinations, includ-
ing Pic-Clor 60, Telone C-35, a combination of 1,3-dichlo-
ropropene and 35% chloropicrin, has been the most exten-
sively evaluated in Florida field trials since 1994. Due to
changes in personal protective equipment (PPE) and buffer
zone requirement, field research focus has shifted towards
evaluations of prebed and drip applications rather than in-
bed or broadcast treatment. To avoid the requirement for
use of half face respirators, Telone II can be injected to
flat soil prior to any soil mounding or bed forming opera-
tion (PreBed) to a depth of at least 12 inches below the
final bed top with the second fumigation pass applying the
chloropicrin in the bed at 8 to 9 inches below the final bed
top. Prebed applications of Pic-Chlor 60 or Telone C35,
or more recently with drip applications of Telone Inline or
Pic-Clor 60 EC continue to be field evaluated for pest con-
trol efficacy and avoidance of PPE requirement.


Research conducted in Florida and areas of the south-
east appear to support the general conclusion that reason-
ably consistent soilborne pest and disease control can
be obtained with prebed applications of Telone C35 (35
gal/A) or Telone II, applied at 12 gallons per treated acre
followed by chloropicrin applied in the bed at 150 pounds
per treated acre. In combination with Telone II, Telone C35
or Chloropicrin, use of a high barrier or virtually imperme-
able mulch film (VIF) will generally improve fumigant
performance and reduce soil gas emissions. After EPA
completion of fumigant reregistration (expected December
2009), EPA will only recognize use of some brand spe-
cific high barrier or true VIF mulch films as an approved
method to mitigate new regulatory constraints to be placed
on use of soil fumigants. With use of the impermeable VIF
mulches, fumigant rates can be reduced 25 to 40% from
maximum labeled application rates. Due to use restrictions
for all Telone products in Dade County, either metham
sodium or metham potassium at 75 and 60 gallons per
acre respectively, in combination with shank injections of
chloropicrin (150 pounds per treated acre) and appropriate
herbicide(s) are currently defined as the best alternatives to
methyl bromide.

Given the general lack of herbicidal activity associated
with the alternative fumigants, weed control is usually
assigned the highest pest management priority for most
methyl bromide alternative chemical systems. Regardless
of crop, separate application of one or more herbicides is
a requirement for effective weed control with any methyl
bromide chemical alternative system. In general, weed con-


Table 1. Generalized Summary of maximum use rate and relative effectiveness of various soil fumigant alternatives to
methyl bromide for nematode, soilborne disease, and weed control in Florida.
Relative Pesticidal Activity
FUMIGANT CHEMICAL Maximum Use Rate Nematode Disease Weed
1) Methyl bromide 67/332 350 Ib Excellent Excellent Good to Excellent
2) Chloropicrin2 300 Ib None to Poor Excellent Poor
3) Methyl iodide1' 2 350 Ib Good to Excellent Good to Excellent Good to Excellent
4) Metam Sodium2 75 gal Erratic Erratic Erratic
5) Telone II 18 gal Good to Excellent None to Poor Poor
6) Telone 017 26 gal Good to Excellent Good Poor
7) Telone C35 35 gal Good to Excellent Good to Excellent Poor
8) Pic-Clor 60 250 Ib Good to Excellent Good to Excellent Poor
9) Potassium N -
Methydithiocarbamate 60 gal Erratic Erratic Erratic
(Kpam)2
EPA Federal registration approved June 4, 2008; State of Florida, FDACS approved July 7, 2008.
2 Currently under EPA review within Fumigant Reregistration Process with potential changes to maximum application rate, personal protec-
tive equipment, buffer zone, and other new restrictions and requirements.


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Vegetable Production Handbook


Table 2. Recommended alternative fumigant and herbicide treatment regime to that of methyl bromide for Florida1 tomato,
pepper, eggplant, and strawberry crops. All rates expressed per treated acre. To achieve maximum weed control an
application of Metam Sodium (Vapam) at 75 gal/A or Metam Potassium (KPam) at 60 gal/A should be included to
all recommended products using a mini coulter applicator or through a drip application using double drip tapes.
Crop Treatment Application Procedure Herbicide Rate
Telone C35 Pre-Bed2, under LDPE, High Barrier or VIF Mulch
35 gal/A Film3; applied 3-5 weeks before transplanting Napropamide (21b)
Telone II Telone Pre-Bed2, Chloropicrin In-bed under LDPE, S-metolachlor (0.95 Ib)
12 gal/A High Barrier or VIF Mulch Film3; applied 3-5 weeks
Tomato before transplanting Postemergent
Chloropicrin Halosulfuron (0.036 Ib)
150 Ilb/A
Pic-Clor 60 Pic-Clor 60 Pre-Bed2 under LDPE, High Barrier or VIF
250-300 Ib/A Mulch Film3; applied 3-5 weeks before transplanting
Telone C35 Pre-Bed2, under LDPE, High Barrier or VIF Mulch
35 gal/A Film3; applied 3-5 weeks before transplanting
Telone II Telone Pre-Bed2, Chloropicrin In-bed under LDPE,
12 gal/A High Barrier or VIF Mulch Film3; applied 3-5 weeks
Pepper before transplanting Napropamide (2 Ib)
Chloropicrin S-metolachlor (0.71 Ib)
150 Ilb/A
Pic-Clor 60 Pic-Clor 60 Pre-Bed2 under LDPE, High Barrier or VIF
250-300 Ib/A Mulch Film3; applied 3-5 weeks before transplanting
Telone C35 Pre-Bed2, under LDPE, High Barrier or VIF Mulch
35 gal/A Film3; applied 3-5 weeks before transplanting
Telone II Pre-Bed2, under LDPE, High Barrier or VIF Mulch
12 gal/A Film3; 3-5 weeks before transplanting
Eggplant Chloropicrin
150 Ilb/A
Pic-Clor 60 Pic-Clor 60 Pre-Bed2 under LDPE, High Barrier or VIF
250-300 Ib/A Mulch Film3; applied 3-5 weeks before transplanting
Telone C35 Pre-Bed2, under LDPE, High Barrier or VIF Mulch Napropamide (4 Ib)
Strawberry 35 gal/A Film3; 4-5 weeks before transplanting Oxyfluorfen (0.5 Ib)

1 Crop recommendations for Pic-Clor 60, Telone II or Telone C35 do not apply to the Homestead, Dade County production region of south Florida where soil types and water
tables currently prohibit product use.
2 To avoid requirement for use of half face respirators, inject Telone II, Telone C35, or Pic-Clor 60 to flat soil prior to any soil mounding or bed operation (PreBed) to a depth of at
least 12 inches below the final bed top.
3 In combination with fumigant, use of a EPA approved high barrier or virtually impermeable mulch film (VIF). With use of the mulch, fumigant rates can be reduced 25 to 40%
from maximum pesticide labeled application rate.


trol with these alternative fumigants (including the Vapam
or KPam) plus herbicides is reported as good or better
than that of methyl bromide. There are however numerous
examples of less than ideal herbicide performance in which
various grasses and broadleaf weeds were not effectively
controlled. The problems incurred usually demonstrate the
importance of soil conditions, incorporation method, and
improper rate calibration for good weed control, as well as
for inducing significant phytotoxic effects and cause for
resultant yield losses.

Herbicide Partners
In addition to Telone II plus chloropicrin, Telone C35,
or PicClor 60, additional applications of appropriate


herbicides will be necessary to provide weed control for
any CUE crop (Table 2). For tomato, follow the fumi-
gant prebed application of Telone C35 or Telone II and
Chloropicrin with a tank mix of napropamide (2 pounds)
and s-metolachlor (0.95 pounds) per treated acre applied
to the top of the raised bed at plastic laying for weed
control. An additional application of halosulfuron (0.024
pounds) as a post-emergent, directed spray for nutsedge
control may be necessary. For strawberry, the fumigant
application of Telone C35 is supplemented by a herbicide
tank mix of oxyfluorfen (0.5 pounds) plus napropamide
(4 pounds) per treated acre, to the raised bed surface
at plastic laying. (Note: A minimum 30-day interval is
required before transplanting when using oxyfluorfen.) In


Page 50







Chapter 6: Alternatives to Methyl Bromide Soil Fumigation for Florida Vegetable Production


pepper, a herbicide tank mix of napropamide (2 pound)
and s-metolachlor (0.71 pounds) per treated acre is applied
after the Telone II Pre-Bed and Chloropicrin injection to
the raised bed at plastic laying for weed control. Recent
research on soil application technologies in Georgia have
demonstrated improved nutsedge control with metam sodi-
um or potassium applied through a series of minicoulters
to the established plant bed just before installation of the
plastic mulch. Good control of yellow and purple nutsedge
has also been recently demonstrated in limited tomato tri-
als with Eptam (S-ethyl dipropylthiocarbamate), however
these applications are only safe when used under LDPE
(conventional) mulch.



HIGH BARRIER / VIRTUALLY IMPERMEABLE
PLASTIC MULCH FILMS (VIF)

Since the early 1960's, low density polyethylene mulch
film (LDPE) has been used as an integral component of the
raised bed, methyl bromide soil fumigation, seep irrigated
vegetable production system of Florida. In this system, the
mulch is important because it confers effective nonchemi-
cal weed control and minimizes evaporative losses of
water from soil and nutrient leaching due to frequent rain-
fall. Use of LDPE is also a federal label requirement for
use of methyl bromide, where it must be installed imme-
diately after fumigant injection into soil. Unfortunately, as
much as 30 to 80% of the methyl bromide applied to soil is
estimated to escape the plant bed through the LDPE mulch
cover. It is obvious that the barrier properties of LDPE to
fumigant gases is quite poor, particularly given the 0.7 to
1.2 mil thick films typically used in Florida agriculture.
In general, the wide range in outgassing losses of methyl
bromide is not just due to the permeability of the plastic
mulch cover, but to the range in cultural practices and
environmental conditions (hot, dry) occurring at the time
of soil fumigation.

The permeability (the ability to pass through) of plastic
mulch to a fumigant gas is directly related to the thickness,
density, and chemical composition of the plastic sheet.
Regardless of composition, thicker mulches are generally
less permeable to methyl bromide than are thin mulches.
In most cases, practical and cost efficiency considerations
prevent the use of thicker LDPE mulches for enhanced
containment of methyl bromide soil gases. There are how-
ever other, more impervious, plastic mulches commercially
available which can provide a much better diffusion barrier
to methyl bromide and other soil fumigants. These new
low permeability films, and the classification scheme to
describe them, include totally impermeable films (TIF),
virtually impermeable films (VIF), and semi-impermeable
films (SIF) which include the metalized films. These films,
compared to standard polyethylene (PE) films, can reduce


fumigant emissions to the atmosphere and via improved
containment in soil and cumulative time x concentration
products, improve fumigant performance even at reduced
rates of fumigant application.

As indicated, significant barrier to fumigant outgassing
has been achieved with VIF mulches. VIF mulches, the
most widely studied, are typically manufactured as multi-
layer films composed of barrier polymers such as ethylene
vinyl alcohol (EVOH) or polyamide (nylon) sandwiched
between other polymer layers (typically LDPE) that keep
the barrier polymers from swelling. Compared to LDPE
mulches, certain VIF films are over 20,000 times less per-
meable to methyl bromide and other fumigant compounds.
The permeability of these mulches is however subject to
variation induced by physical and suboptimal environmen-
tal condition. For example, VIF has been shown to have
extremely low permeability under laboratory conditions
(before tarping), but its permeability can change signifi-
cantly under field conditions after tarping. After laying the
plastic in the field, some SIF and VIF mulch films may be
as much as 2 to 3 times more permeable to a given fumi-
gant gas than they were under laboratory condition. This
is thought to be due to a breakdown in the VIF properties
under field conditions caused by the stretching and crack-
ing of the middle, low permeability layer during tarping.

Quantitatively, the permeability of LDPE, TIF, VIF and
other SIF mulch films to a fumigant gas were formerly
expressed as the amount of a fumigant (grams) passing
through the mulch cover per unit time (hr) anc per unit sur-
face area. VIF mulches were first developed and mandated
for use in Europe, where to be labeled VIF, film manu-
facturers were forced to comply with a standard testing
protocol (NFT 54-105), established by the French Ministry
of Agriculture. The French standard specifies that in order
for a film to be classified as VIF, its permeability to methyl
bromide could not exceed 0.20 g/m2/hr. Alternative stan-
dards for expressing permeability, such as the mass transfer
coefficient, are now being adopted for use in defining high
barrier and gas impermeable plastic mulches.

This new reference standard, the Mass Transfer
Coefficient (h) of fumigant compounds across agricultural
films, is a measure of the resistance to diffusion which,
unlike the French standard, is a property of the film /
chemical combination and is independent of the concen-
tration gradient across the film. The French method com-
putes permeability based on fumigant flux or fluctuation,
so many grams of fumigant per unit surface area per unit
time. As a measure of permeability, the French standard
is thus dependent (and will necessarily change) upon the
concentration gradient or concentration difference occur-
ring on each side of the film. In the French method, the
concentration difference between sides is seldom the same
(not standardized), and thus cannot be compared between


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Vegetable Production Handbook


independent laboratory based estimates. The Mass Transfer
Coefficient method however, uses static sealed cells; where
a fumigant gas is introduced (spiked) to one side of the
film and the concentrations on both sides of the film are
then monitored until an equilibrium is reach (same on both
sides). The mass transfer coefficient characterizes the equi-
librium condition, and thus provides an intrinsic signature
measure of the permeability of a film to a chemical which
is not dependent on the chosen concentration gradient.
Because the new method produces such a sensitive and
reproducible measure of film permeability between labora-
tories, it is now being widely adopted as the new yardstick
for comparing fumigant permeabilities among the high bar-
rier plastic mulches.

During the past decade, many small plot and large scale
field trials have been conducted in Florida to evaluate the
use of high barrier SIF and VIF mulch films to reduce
methyl bromide field application rates, reduce soil emis-
sions, and to compare crop yield and pest control efficacy.
In general, the results of these trials have indicated no sig-
nificant loss of pest control efficacy or of crop yield when
applications rates of methyl bromide were reduced as much
as 25 to 50% when reduced rates were accompanied by the
use of a VIF or high barrier SIF mulch. In a number of tri-
als, attempts to further reduce use rates by more than 50%
resulted in a loss of pest control efficacy and crop growth
performance. Opportunities for reducing field application
rates of other fumigants without compromising pest control
efficacy or crop yield have also been demonstrated with
methyl iodide.

More recently, field research has demonstrated that
certain metalized mulches (Canslit) had significant bar-
rier, VIF-type qualities. The thin coating of aluminum was
demonstrated to retain higher methyl bromide concentra-
tions in soil for longer periods of time, and thus provided
effective weed control (ie., nutsedge), with reduced rates of
methyl bromide comparable to that of true VIF mulch film.
The utility of the metalized mulch for allowing reduced
fumigant application rate has also been demonstrated in
other states of the southeast. The more efficient contain-
ment of gases below the barrier mulch has also resulted in
cases of crop phytotoxicity. To use the high barrier mulch
technology, plantings may have to be delayed to insure soil
residues have dissipated and plant injury will not occur.
A monitoring program using colormetric detector tubes
(GasTek, Kitagawa, Sensidyne) or VOC meters to assess
residual fumigant gases in soil should be considered before
a commitment to planting is made.

Noteworthy problems have been encountered with
some VIF mulches. In some strawberry trials, where taller
yet narrower beds are used, the slick, nonembossed VIF
mulches could not be installed without the need for signifi-
cant hand labor. Since the VIF plastics were not embossed,
they demonstrated a tendency to slip from under the rear


press wheels during installation causing significant reduc-
tions in tractor speeds and frequent stoppages in the plastic
laying operation. The problem with use of nonembossed
does not appear to be as severe in tomato or pepper where
the raised plant beds are wider and not as tall as that of
strawberry. Since these VIF mulch have no stretch capa-
bility, adding 2 inches of width to the roll (if possible)
has in many cases reduced, not eliminated, problems of
field installation in strawberry by providing more plastic
at the tuck in the row middle. With the appearance of
many newly formulated VIF products, including the new
embossed high barrier mulches, the previous problems of
installation may be largely resolved.

From a practical standpoint, grower adoption of VIF or
other high-barrier films, coupled with reduced soil fumi-
gant application rate will require continued in-field evalua-
tions, with continued refinement of field installation appli-
cation technologies and evaluations of reduced rate pest
control efficacy. Increased use of SIF and VIF mulch films
must also consider changes in cost and manufacturing
source. In previous years it was difficult to name more than
a few, confirmed VIF mulch films. Many if not most of
these VIF films were produced in Europe or Mediterranean
countries. They were expensive, and in many cases, very
difficult to quickly acquire. Today, over a dozen different
manufacturers or product lines can be identified which
claim high barrier, VIF status. Many of these new high
barriers and VIF products are now being produced in the
U.S. and Canada. For the overseas producers, transport
and needs for U.S. customs clearance, Florida users may
incur lengthy delays (upwards of 2-3 months) for delivery
of ordered products from European manufacturers. In this
regard, growers acquiring films from these manufacturers
should be encouraged to order necessary products well in
advance of the time of need in the field.

Probably the single most important reason for using
a VIF or other high barrier SIF plastic mulch involves
the rising cost and scarcity of methyl bromide with each
new CUE approval. There are other, equally important
reasons for adopting high barrier, VIF mulch technolo-
gies. In July 2009, EPA finalized and amended the revised
Reregistration Eligibility Decisions (RED) for methyl
bromide, chloropicrin, metam sodium (Vapam) and metam
potassium (Kpam). The RED's clearly enumerate a number
of significant regulatory changes that are forthcoming for
all of the alternative fumigants just completing EPA rereg-
istration. These new proposed label constraints include
requirements for additional product and OSHA approved
pesticide safety training, medical certification, respirator
fit testing, and other personal protective equipment for
field workers, as well as expanded buffer zones between
agriculturally treated lands and urban residential property
and or occupied structures. As currently described by EPA
in their proposed 2008 risk mitigation options, the expan-
sion of buffer zone requirements will be dependent on field


Page 52







Chapter 6: Alternatives to Methyl Bromide Soil Fumigation for Florida Vegetable Production


application rate (the higher the field use rate, the bigger
the buffer zone from residential property line or occupied
structures required). Any new buffer zone and use rate
restriction will surely mandate a more intensive, overall
re-evaluation of alternatives and reduced rate applica-
tion technologies, including use of high barrier VIF type
mulches to assure pest control efficacy and crop response
consistency. Unfortunately, EPA is currently only recog-
nizing use of a few, relatively specific high barrier or true
VIF mulch films as an approved method to mitigate buffer
zone distance requirement.



REDUCED RATE APPLICATION TECHNOLOGIES

Currently, soil injection equipment for methyl bromide
is designed to dispense as much as 25 to 30 gallons of a
liquid fumigant compound through armored lines from
the gas cylinder, to the flow meter and rear manifold and
then through each of three chisel per bed. The system is
designed and calibrated to do this while moving at 3V2 to
5 mph, uniformly dispensing multiple liquid streams of
fumigant within 7260 to 10, 890 linear feet of row per
acre. With such high rates, the flow lines are full, with
liquids moving as continuous streams without in-line voids
or bubbles. At reduced rates of application, such as those
demanded for use with high barrier or VIF film, the situa-
tion may be vastly different.

Methyl bromide is a colorless, odorless, liquid under
certain conditions of pressure and temperature. At tem-
peratures below the boiling point of 380 F, or within the
confines of a pressurized cylinder, methyl bromide exists
as a liquid. At temperatures typical of field application in
Florida, methyl bromides rapidly volatilizes to a gas once
release from the pressurized cylinder into the ambient pres-
sure of air or soil. With such a high vapor pressure (1420
mmHg), methyl bromide can even exist as bubbles of gas
within the distribution lines if metered flow rates are low
and do exceed the total capacity of the delivery tubing
and manifold system. With reduced flow and presence of
bubbles within lines, a significant loss of back pressure
occurs at the chisel orifices. The dramatic fall in back
pressure with reduced rate prevents accurate and uniform
flow of the fumigant between chisels. This occurs at the
point where total internal volume (flow capacity) of 9
chisel tubes, typically '4 inch in diameter, exceeds the flow
capacity of a 34 armored delivery hose from the flow meter.
When the outflow potential is greater than inflow then
you have a significant loss of pressure, and without back
pressure the system becomes one of gravity flow. With
the existing on-farm systems, accuracy cannot be achieved
at such low volumes, and without significant back pres-
sure. To resolve the back pressure problem, it is extremely
important to reduce total line volume and/or diameter of
the delivery tubes from the manifold to the chisels so as to
guarantee adequate back pressure at the point of fumigant


release. With a high barrier mulch, reducing the field appli-
cation rate of a fumigant results in a greatly reduce rate
of liquid flow. Some chisels are so reduced in flow that
accuracy and uniformity of application along the row was
compromised along with pest control efficacy.

As indicated previously, use of VIF or high barrier plas-
tic mulch films will be a required component of the any
methyl bromide transition strategy. Use of these more gas
retentive mulches will however, require changes in field
application and soil injection equipment to insure accurate
and uniform dispensing of such low fumigant application
rates (5 to 10 gallons per acre). These required changes
include smaller delivery tubing size (1/8 to 1/16 inch diam-
eter), installation of sight gauges to monitor flow unifor-
mity among chisel streams, and installation of a low pres-
sure gauge upstream of the flow divider to monitor overall
back pressure (at least 15 psi) at the flow divider (Table
3). For additional, more comprehensive information, read-
ers are advised to review "Application Considerations
for Successful Use of VIF and Metalized Mulches with
Reduced Fumigant Rates in Tomato ". Appendix ; or
http://edis.ifas.ufl.edu/HS270)



TRANSITION RISKS

Transition refers to an incremental change from cur-
rent status. Defined in this way, the transition from methyl
bromide fumigation is the change from a 40-year-old sys-
tem of being totally reliant on methyl bromide to a new
multi-tactic pest control and crop production system. The
transition will surely require a complete analysis of the
entire production system. The transition is not likely to be
easy or seamless. If the transition plans are well designed
and implemented effectively, problems are likely to be few.
Unavoidably however, some factors that affect the success
or failure of the various tactics, such as the environment,
may not be completely manageable or resolvable. For
example, seasonal differences in temperature and rainfall



Table 3. Summary of recommended fumigant injection
equipment modifications required for use of
high barrier/ VIF mulch and reduced rate appli-
cations of soil fumigants.
Replace tubing from manifold to chisels with smaller diameter
poly tubing to compensate for the new reduced flow capacity
requirement and to increase line back pressure needed to insure
accurate, uniform flow.
To the manifold flow divider, install individual sight gauges to
observe uniformity of fumigant liquid flow to each chisel outlet.
Install a low pressure gauge (0-30 psi) immediately upstream
of the manifold or flow divider to insure at least 15 psi of back-
pressure.
Insure that the flow meter registers a minimum of 10% flow.


Page 53







Vegetable Production Handbook


patterns can adversely effect fumigant dissipation from
soil, and herbicide efficacy and thus reduce the value of
the alternative by causing treatment inconsistency. Growers
can also cause significant response variability due to
inappropriate land preparation or substandard application
procedures. Another newly emerging concern is the risk
created by the differential plant-back restrictions of some
of the newly registered herbicide compounds that have to
be added for weed control with the alternative fumigants.
The impacts on the ability to double crop, as well as poten-
tial direct yield reduction as a result of carryover from row
middle or previous crop applications, are also of concern.


Effective transition planning can only be achieved
through a collaborative effort involving the grower and his
field staff, commodity organization involvement, assisted
by university research and extension personnel. Working
together, the team should craft a realistic transition plan
that addresses many of the production concerns and incon-
sistencies. The transition plan would also surely highlight
the imperative that Florida fruit and vegetable growers
actively begin the transition, to increased reliance upon the
alternative fumigants as a percentage of their total farmed
acreage.


Page 54






UF UNIVERSITY of
UF FLORIDA
IFAS Extension
2010-2011


Cole Crop Production in Florida

S.M. Olson, E.H. Simonne, W.M. Stall, G.E. Vallad, S.E. Webb, and S.A. Smith


BOTANY
Nomenclature
Family Brassicaceae (Cruciferae)
Broccoli Brassica oleraceae Italica group
Cabbage Brassica oleraceae Capitata group
(Fig. 7-1)
Cauliflower Brassica oleraceae Botrytis group
(Fig. 7-2)
Collards Brassica oleraceae Acephala group
Kale Brassica oleraceae Acephala group
Mustard Brassica juncea
Turnip Brassica rapa Rapifera group (Fig. 7-3)

Origin
It is believed that all of the crops within B. oleraceae
evolved from a wild cabbage-like plant that was native to
the British Isles and to the Mediterranean area of Europe.

Related Species
Other vegetables in the Brassicaceae family are horse-
radish, rutabaga, Brussels sprouts, kohlrabi, Chinese cab-
bage, radish, and watercress. Many ornamental plants and
oil-bearing plants also are included in this family.


VARIETIES
Florida cabbage varieties are shown in Table 1. Other
cole crop varieties are shown in Table 2.

Table 1. Some cabbage varieties grown in Florida.

Green Red
Atlantis (H) Green Cup (H) Cardinal (H)
Augusta (H) Isalco (H) Red Dynasty (H)
Blue Dynasty (H) Matsuma (H) Red Success (H)
Bravo (H) Pruktor (H) Red Rookie (H)
Cheers (H) Ramada (H)
Ducati (H) Rio Verde (H)
Emblem (H) Royal Vantage (H)
Gideon (H) Solid Blue 790 (H)
Gloria (H) Tropicana (H)

Savoy
Savoy Ace (H)

H = hybrid.


SEEDING AND PLANTING

Seeding and planting information for cole crop produc-
tion in Florida is given in Table 3.


FERTILIZER AND LIME
Soil test and fertilizer recommendations for cole crops
grown on mineral soil are shown in Table 4.

For unmulched crops planted in single rows or beds,
broadcast all P205, micronutrients, and 25 to 50% of N and
K20 before planting. Banding these fertilizers at planting
might improve fertilizer efficiency. Sidedress remaining N
and K20 at 6 to 8-leaf stage.

For unmulched leafy cole crops planted in multi-row
beds, broadcast P205, micronutrients, and 25 to 50% of the
N and K20 in the bed area. Topdress or band remaining N
and K20 when plants are 4 to 6 inches tall. Apply supple-
mental N and K20 (as above) after leaching rain.



Table 2. Broccoli, cauliflower, collard, kale, mustard, and
turnip varieties grown in Florida.


Broccoli:
Arcadia (H)
Marathon (H)
Major (H)
Packman (H)
Patriot (H)
Pirate (H)
Cauliflower:
Majestic (H)
White Passion (H)
Snow Crown (H)
Collards:
Blue Max (H)
Bull Dog (H)
Flash (H)
Georgia
Top Bunch (H)
Top Pick (H)
Vates
H = hybrid.


Kale:
Blue Ridge (H)
Vates
Mustard:
Florida Broad Leaf
Green Wave
Red Giant
Southern Giant Curled
Tendergreen
Turnip:
Just Right (H)
Southern Green
Purple Top
Royal Crown (H)
White Knight (H)
Turnip Greens:
Seven Top


Page 55


Chapter 7.







Vegetable Production Handbook


Table 3. Seeding and planting information for cole crops in Florida.

Planting dates Broccoli1 Brussels sprouts Cabbage1 Cauliflower'
North Florida Aug Feb Aug Feb Aug Feb Aug Feb
Central Florida Sept Feb Sept Feb Sept Feb Sept Feb
South Florida Oct Jan Oct Jan Sept Jan Sept Jan
Seeding information
Distance between rows (in) 24 40 24 40 24 40 24 40
Distance between plants (in) 10- 15 18 24 9-16 12- 18
Seeding depth (in) 0.25 0.5 0.25 0.5 0.25 0.5 0.25 0.5
Seeding per acre for field (Ib) 1 2 1 2 1 2 1 2
Seeding per acre for transplant (Ib) 1.25 1.5 1.25 1.5 1 1.25 1.5
Days to maturity from seed 75-90 90 120 85- 110 75-90
Days to maturity from transplant 50 70 70 90 70 90 50 70
Plant populations2 (per acre) 26,136 15,520 29,403 29,040
Planting dates Collards Kale Mustard Turnip
North Florida Aug Feb Aug Feb Aug Feb Aug Feb
Central Florida Sept Feb Sept Feb Sept Feb Sept Feb
South Florida Sept Jan Sept Jan Sept Jan Sept Jan
Seeding information
Distance between rows (in) 24 -36 18 24 12 -36 12 -36
Distance between plants (in) 12 24 8-12 5-10 2 6
Seeding depth (in) 0.25 0.5 0.25 0.5 0.25 0.5 0.25 0.5
Seeding per acre for field (Ib) 2 4 2 -4 3-5 2 -3
Seeding per acre for transplant (Ib) 1.25 1.5 N/A3 N/A3 N/A3
Days to maturity from seed 70 90 50 70 40 50 40 60
Days to maturity from transplant 50 70 -
Plant populations2 (per acre) 21,780 43,560 116,160 261,360
1 Can be seeded in double rows per bed: 15 24 in between rows, 10 -12 in within rows on 40 to 60-inch bed centers.
2 Populations based on closest between and within row spacing,
3 Generally direct seeded.


For mulched crops with subsurface irrigation, incor-
porate all P205, micronutrients, and 20 to 25% of N and
K20 in the bed (Fig. 7-4). Apply remaining N and K20 in
a single groove (for twin-row) in bed center about 2 to 3
inches deep before mulching. Supplemental N and K20
can be injected through mulch with a liquid fertilizer injec-
tion wheel.

For mulched crops with overhead sprinkler irrigation,
incorporate all fertilizer in bed before mulching. Bed over
fertilized soil with unfertilized soil so that fertilized soil
will be deep enough (3 to 4 inches) to remain moist.

For Histosols, all P205, K20, and micronutrients can
be broadcast just before planting, although banding P205
at planting might increase P efficiency. Some N might be
needed for crops started under cool, winter conditions. A
total of 40 to 50 lb N per acre might be needed at planting
or as a sidedress early in the season (see Table 5).

For drip-irrigated crops, (broccoli, cauliflower, cab-
bage, collards) apply all P205, micronutrients, and up to
20 to 25% of N and K20 in the bed at planting. Apply
remaining N and K20 through tube using schedules pre-
sented in Table 6a and 6b.


For leafy cole crops other than those listed here, follow
recommendations for mustard.



PLANT TISSUE ANALYSIS

Plant tissue analysis for cole crops is listed in Table 7.



PETIOLE SAP TESTING

Fresh sap can be pressed from leaf petioles and ana-
lyzed for nitrogen and potassium concentrations. Results
can be used to make adjustments in the fertilization pro-
gram. Sufficiency ranges for sap testing broccoli and col-
lards are presented in Table 8.



IRRIGATION

Slight variations exist in the water requirements of
members of the cole crop family (see Chapter 3, Principles
and Practices of Irrigation Management for Vegetables,
Tables 4-6). Water use rates may approach ETo (see
Chapter 3, Table 3) during the rapid growth and develop-


Page 56







Chapter 7: Cole Crop Production in Florida


Table 4. Soil test results and fertilizer recommendations for cole crops on mineral soils.1

Target pH N Ib/A VL L M H VH VL L M H VH

P205 (lb/A/crop season) K20

Broccoli/Cauliflower/Brussels sprouts
6.5 175 150 120 100 0 0 150 120 100 0 0
Cabbage/Collards/Chinese cabbage
6.5 175 150 120 100 0 0 150 120 100 0 0
Kale/Turnip/Mustard
6.5 120 150 120 100 0 0 150 120 100 0 0
1 See Chapter 2 section on supplemental fertilizer application and best management practices, pg 11.


Table 5. Soil test and fertilizer recommendations for cole crops grown on Histosols, with target pH 6.0 and N rate= 0 lb/A.

__P and K index and fertilizer rate
Crop P index 3 6 9 12 15 18
Broccoli, Cauliflower P205 (lb/A) 200 140 80 20 0 0
Cabbage P205 (lb/A) 200 140 80 20 0 0
Chinese cabbage P205 (lb/A) 280 220 160 100 40 0
K index 50 80 110 140 170 200
Broccoli, Cauliflower K20 (lb/A) 200 140 80 20 0 0
Cabbage K20 (lb/A) 200 140 80 20 0 0
Chinese cabbage K20 (lb/A) 200 140 80 20 0 0


Table 6a. Injection schedule for N and K for cole crops planted two rows per bed on 6-foot centers on soils very low in K.

Total nutrients (lb/A)3 Crop development Injection (Ib/A/day)1
Crop N K20 Stage Weeks2 N K20
Broccoli 175 150 1 1 2.0 1.75
Cauliflower 175 150 2 9 2.5 2.25
Cabbage 175 150 1 3 2.0 2.0
Collards 175 150 2 6 2.5 2.5
Chinese cabbage 175 150 3 2 2.0 2.0
1 All nutrients injected. Actual amounts may be lower depending on amount of N and K20 placed in the bed, the K soil test result, and the crop N requirement.
2 Starting from date of seedling emergence or transplanting. First two weeks worth of injecting can be omitted if 25% of total N and K20 was applied preplant.
3 Seeds and transplants may benefit from applications of a starter solution at a rate no greater than 10 to 15 lbs/acre for N and P205, and applied through the plant hole or near
the seeds.


ment period, decreasing to 85% of that value during final
growth. Reductions in available water to the plants will
result in reduced growth and development of leaves and
shoots. Winter season water use in south Florida may aver-
age 0.10 inches per day (2700 gal/A/day), while in north
Florida, requirements may average 0.06 inches per day
(1600 gal/A/day), a 40% difference. Therefore, close atten-
tion to local climatic conditions is necessary for proper
water management and irrigation scheduling.



WEED MANAGEMENT
Herbicides labeled for weed control in Cole crops are
listed in Table 9.


DISEASE MANAGEMENT
Information on managing diseases of cole crops is given
in Table 10.


INSECT MANAGEMENT
The key pest of cole crops in Florida is the diamond-
back moth. Resistance to insecticides, particularly to pyre-
throids, is very common. If diamondback moth larvae are
present, growers should avoid pyrethroids and use Bacillus
thuringiensis products (both aizawa and kurstaki strains)
as their main insecticides and tank mix or alternate with
spinosad or emamectin benzoate. If cabbage looper is pres-
ent, in addition to diamondback moth larvae, an application


Page 57







Vegetable Production Handbook


of methomyl may be necessary. Another choice is thiodicarb
but this will be more damaging to beneficial insects than
methomyl, which has a short residual effect. If diamondback
moth is not present and cabbage looper is the main pest, a
pyrethroid would be effective. Tebufenozide will also con-
trol cabbage looper but not diamondback moth larvae.


The insecticides currently approved for use on insects
attacking cole crops are outlined in the following tables:
Cole Crops Table 11
Turnip Table 12

PRODUCTION COSTS
Example breakeven production costs for cabbage are
given in Table 13.


Table 6b. Supplemental fertilization recommendations for cole crops grown in Florida on sandy soils testing very low in
Mehlich-1 potassium (K20).

Recommended-Supplemental fertilizationz
Production Measured "low" plant
System Nutrient Leaching raint" nutrient content xw..V Extended harvest season x.
Plasticulture N n/a 1.5 to 2 Ibs/A/day for 7 days Y 1.5 to 2 Ibs/A/day Yv
K20 n/a 1.5 to 2 Ibs/A/day for 7 days Y 1.5 to 2 Ibs/A/day Yv
Bare ground N 30 Ibs/As 30 Ibs/A8 30 Ibs/A v
K20 20 Ibs/As 20 Ibs/As 20 Ibs/A v
z 1 A= 7,260 linear bed feet per acre (6-ft bed spacing); for soils testing "very low" in Mehlich 1 potassium (K20)
y Fertilizer injections may be done daily or weekly. Inject fertilizer at the end of the irrigation event and allow enough time for proper
flushing afterwards.
x Plant nutritional status may be determined with tissue analysis or fresh petiole-sap testing, or any other calibrated method. The "low" diagnosis needs to be based on UF/IFAS
interpretative thresholds.
w Plant nutritional status must be diagnosed every week to repeat supplemental application.
v Plant nutritional status must be diagnosed after each harvest before repeating supplemental fertilizer application.
u Supplemental fertilizer applications are allowed when irrigation is scheduled following a recommended method (see Chapter 3 on
irrigation scheduling in Florida). Supplemental fertilization is to be applied in addition to base fertilization when appropriate.
Supplemental fertilization is not to be applied "in advance' with the preplant fertilizer.
t A leaching rain is defined as a rainfall amount of 3 inches in 3 days or 4 inches in 7 days.

s Supplemental amount for each leaching rain.




Table 7. Plant tissue analysis for cole crops. Dry wt. basis.

N P K Ca Mg S Fe Mn Zn B Cu Mo
Status Percent Parts per million
Broccoli Most recently matured leaf sampled at heading
Deficient <3.0 0.3 1.1 0.8 0.23 0.2 40 20 25 20 3 0.04
Adequate range 3.0-4.5 0.3-0.5 1.5-4.0 0.8-2.5 0.23-0.40 0.2-0.8 40-300 25-150 45-95 30-50 5-10 0.04-0.16
High >4.5 0.5 4.0 2.5 0.40 0.8 300 150 100 100 10 0.16
Cabbage Most recently matured leaf sampled 8 weeks after planting
Deficient <3.0 0.3 2.0 0.5 0.20 0.3 30 20 30 20 3 0.3
Adequate range 3.0-6.0 0.3-0.6 2.0-4.0 0.8-2.0 0.25-0.60 0.3-0.8 30-60 20-40 30-50 20-40 3-7 0.3-0.6
High >6.0 0.6 4.0 2.0 0.60 0.8 100 40 50 40 10 0.6
Cauliflower Most recently matured leaf sampled at buttoning
Deficient <3.0 0.4 2.0 0.8 0.25 0.3 30 30 30 30 5 0.5
Adequate range 3.0-5.0 0.4-0.7 2.0-4.0 0.8-2.0 0.25-0.60 0.3-0.8 30-60 30-80 30-50 30-50 5-10 0.5-0.8
High >5.0 0.7 4.0 2.0 0.60 1.0 100 100 50 50 10 0.8
Collards Most recently matured leaf sampled at harvest
Deficient <4.0 0.3 3.0 1.0 0.40 0.3 40 40 25 25 5 0.3
Adequate range 4.0-5.0 0.3-0.6 3.0-5.0 1.0-2.0 0.40-1.00 0.3-0.8 40-100 40-100 25-50 25-50 5-10 0.3-0.8
High >5.0 0.6 5.0 2.0 1.00 0.8 100 100 50 50 10 0.8


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Chapter 7: Cole Crop Production in Florida


Table 8. Sufficiency ranges for petiole sap testing for broccoli and collard.

Fresh Petiole Sap Concentration (ppm)
Crop Development Stage N03-N K
Six-leaf stage 800-1000 NRz
One week prior to first harvest 500-800
First harvest 300-500
z NR-No recommended ranges have been developed.








Table 9. Chemical weed controls: broccoli, cabbage, cauliflower, collards, mustard, turnips and kale.

Time of Rate (Ibs. AI./Acre)
Herbicide Labeled crops application to crop Mineral Muck
Bensulide Brassica (cole) leafy vegetables Cabbage, Preplant incorporate, Preemergence 5-6
(Prefar 4E) Chinese cabbage (Napa, bokchoy), broccoli,
Chinese broccoli, Brussel sprouts, cauliflower,
all Chinese brassica crops collards, kale,
kohlrabi, mezuna, mustard greens, rape greens
Remarks: Preplant incorporate using power driven rotary cultivations or apply preemergence and incorporate with irrigation. Controls many grass
weeds. Provides fair to good control of lambsquarter, purslane, and some amaranths. May be applied under polyethylene mulch.
Clethodim Head and Stem Postemergence 0.09-0.25
(Select 2 EC) Brassicas
(Arrow) Brassica Leafy Vegetables
(Select Max)
Remarks: Postemergence control of actively growing annual grasses. Apply at 6-16 fl oz/acre (Select, Arrow) or 9-16 fl oz/acre (Select Max).
Higher rates are listed for perennial grasses. Use a crop oil concentrate for Select and Arrow, but a non-ionic surfactant may be used for Select
Max. Do not apply within 30 days of harvest for head and stem brassicas (see definition) and 14 days for Brassica leafy greens.
Carfentrazone Brassica Leafy Vegetables Preplant 0.031 0.031
(Aim) (All) Directed-Hooded
Row-middles
Remarks: Aim may be applied as a preplant burndown treatment and/or as a post-directed hooded application to row middles for the burndown of
emerged broadleaf weeds. May be tank mixed with other registered herbicides. May be applied at up to 2 oz (0.031 Ib ai). Use a quality spray adju-
vant such as crop oil concentrate (coc) or non-ionic surfactant at recommended rates.
DCPA Broccoli, Brussels Sprouts, Cabbage, At seeding or Transplanting 6-8
(Dacthal W-75) Cauliflower and all other BRASSICA
(Dacthal DF) (cole) leafy vegetables*
* Including: Chinese broccoli, Broccoli raab rapinii), Chinese cabbage (bok choy, napa), Chinese mustard cabbage (gai choy), collards, kale, kohl-
rabi, mustard greens and rape greens.
Remarks: Can be sprayed directly over transplants without injury. Application should be made prior to weed seed germination. If weeds have
emerged, soil should be clean cultivated or weeded prior to application. Can be preplant incorporated.
Glyphosate Brassica Leafy Vegetables Chemical fallow 0.3 -1.0
(Roundup, Durango Preplant, pre emergence,
Touchdown, Glyphomax) Pre transplant
Remarks: Roundup, Glyphomax and Touchdown have several formulations. Check the label of each for specific labeling directions.
S Metolachlor Transplanted Posttransplant 0.64 1.91
(Dual Magnum) Cabbage (tight-headed)
Remarks: Label is a third party registration by TPR, Inc. The label is issued by TPR and is valid only when a grower indemnification agreement is
signed. Application should be made immediately after transplanting to plants that are at least 5 weeks old or grown in 1" diameter cells or larger.
Use 0.64 Ib ai (.67 pints) on soils relatively course-textured or low in organic matter. Use higher rate (2 pints) on fine textured soils or high in
organic matter. In order to protect ground water resources, do not apply more than 1.91 Ib ai (2.0 pints) of Dual Magnum per crop on sandy soils
or 3.81 Ib ai (4.0 pints) of Dual Magnum per crop on organic soils. Chinese varieties are more sensitive to Dual Magnum injury. Use lower rates as
determined for soil type.


Page 59







Vegetable Production Handbook


Table 9. Continued.

Time of Rate (Ibs. Al./Acre)
Herbicide Labeled crops application to crop Mineral Muck
S-Metolachlor Direct-seeded cabbage Preemergence Postemergence 0.76- 1.26 1.91 -3.82
(Dual Magnum) (direct-seeded)
Remarks: Label is Third Party Registration by TPR, Inc. May be applied preemergence or postemergence to direct seeded tight-headed
cabbage. Preemergence applications should be made immediately after seeding at 0.8 to 1.33 pints/A on sandy soils or 2.0 to 4.0 pints or
organic soils. Postemergence applications should be made at least 20 days after seeding. Apply once per crop season. Chinese varieties
are more sensitive to Dual Magnum injury. Use the lower rates. The use of Dual Magnum may result in leaf crumbling or cupping and twist-
ing. Delayed maturity can be anticipated at higher rates. Climatic conditions during the growing season will affect efficacy and phytotoxicity.
Postemergence application should be made at least 20 days after seeding. Apply once per crop season.
Napropamide Broccoli, cabbage, brussel Posttransplant 2.0
(Devrinol 50DF) sprouts, cauliflower
Remarks: Apply to weed-free surface as a surface spray after transplanting. Sprinkler irrigate within 24 hours using sufficient water to wet
the soil to a depth of 2 to 4 inches. Not labeled for direct-seeded in Florida.
Paraquat Cabbage (including tight Postemergence 0.312-0.47 0.312-0.47
(Gramoxone Inteon) headed Chinese Cabbage) Directed/shielded
Remarks: Apply as a postemergence directed spray/shielded to control emerged annual broadleaf weeds and grasses and for top kill and sup-
pression of emerged perennial weeds after crop emergence or establishment. Apply as a directed spray using 1.2 pts/acre in 40 to 70 gals.
spray mix. Do not allow spray to contact cabbage plants as injury or excessive residue may result. Outer leaves should be stripped at time
of harvest. Add a nonionic surfactant or crop oil to spray volume.
Pelargonic acid Brassica crops (broccoli, cabbage, Preplant, Preemergence, 3-10% v/v 3-10% v/v
(Scythe) cauliflower, collards, kale, Directed-Shielded
greens (mustard and turnip)
Remarks: Product is a contact, non-selective, foliar applied herbicide. There is no residual control. May be tank mixed with soil residual
compounds. Consult label for rates and other information.
Oxyfluorfen Broccoli, Cabbage, Cauliflower Pretransplant 0.25 0.50
(Goal 2XL) (Goaltender)
Remarks: Controls certain annual broadleaf weeds such as: carpetweed, redroot pigweed, common purslane and Pennsylvania smartweed.
May provide suppression of galingosa, common lambsquarter and wild mustard.
Note: Crop injury may result with the use of transplants less than 5 weeks old and grown in containers less than 1 inch square. Do not apply
to fields that have had acetanilide (Dual, Lasso, Ramrod) application during the current growing season. Severe crop injury may occur.
Paraquat Broccoli, Cabbage, Preplant Preemergence
(Gramoxone Inteon) Chinese cabbage,
(Firestorm) Collards, Turnip, Cauliflower 0.5 0.1 0.5 0.1
Remarks: Apply as a band treatment over the crop row or as a broadcast treatment before, during or after planting, but before the emergence
of the crop. Weeds emerging after the application will not be controlled. Crop plants emerged at the time of application will be killed. Use a
non-ionic surfactant in the spray mixture.
Paraquat Cabbage (including tight headed Postemergence 0.312 -0.47 0.312- 0.47
(Gramoxone Inteon) Chinese cabbage) Directed/shielded
Remarks: apply as a postemergence directed spray/shielded to control emerged annual broadleaf weeds and grasses adn for top kill and sup-
pression of emerged perennial weeds after crop emergence or establishment. Apply as a dusted spray using 1 1/2 pts/acre in 40 to 70 gals.
spray mix. Do not allow spray to contact cabbage plants as injury or excessive residue may result. Outer leaves should be stripped at time of
harvest. Do not apply where Gramoxone Extra has been used as a pre-emergence spray. Add a nonionic surfactant or crop oil to spray volume.
Sethoxydim (Poast) Broccoli, Cabbage, Cauliflower, Postemergence 0.188-0.28 0.188-0.28
and all other Brassica (cole)
leafy vegetables*
* Including: Chinese broccoli, Broccoli raab rapinii), Chinese cabbage (bok choy, napa), Chines mustard cabbage (gai choy), collards, kale,
kohirabi, mustard greens and rape greens.
Remarks: Controls actively growing grass weeds. A total of 3 pts. product per acre may be applied in one season. Do not apply within 30
days of harvest. Apply in 5 to 20 gallons of water adding 2 pts. of crop oil concentrate per acre. Unsatisfactory results may occur if applied
to grasses under stress. Use 0.188 lb. ai. (1 pt.) on seedling grasses and up to 0.28 lb. ai. (1.5 pts.) on perennial grasses emerging from rhi-
zomes, etc. Consult label for grass species and growth stage for best control.
Trifluralin Broccoli, Cabbage, Preplant incorporated 0.5 0.75
(Treflan TR-10) Brussels Sprouts, (Direct-seeded and Transplanted) 0.5 -0.75
(Treflan EC) Cauliflower Preplant incorporated
(Treflan MTF) Turnip Greens (for processing), (Direct-seeded)
(Treflan 5) Collard, Mustard, Kale
Remarks: Controls germinating annuals, especially grasses. Incorporate 4 inches or less within 8 hours. Results in Florida are erratic on soils
with low organic matter and clay contents. Note precautions of planting non-registered crops within 5 months.


Page 60







Chapter 7: Cole Crop Production in Florida


Table 10. Disease management cole crops.

Fungicide Max. Rate/ Acre/ Min. Days
Chemical Code1 Applic. Season to Harvest Diseases or Pathogens Remarks2
Be sure to read a current product label before applying any chemical.
Cole Crops
Head and Stem Crops: Broccoli, Brussels Sprouts, Cauliflower, Chinese Broccoli and Chinese Cabbage; Leafy Crops: Collards, Kale,
Mustard and Turnip; and Watercress.


Kocide 2000, Kocide
DF (copper hydroxide)
Kocide 3000
(copper hydroxide)
Nu Cop 50WP (copper
hydroxide)
Champ DP
(copper hydroxide)
Champ WP
(copper hydroxide)
Champ F2
(copper hydroxide)
Cuprofix Ultra 40
Disperss (copper sul-
fate)
Basicop (elemental
copper)
Bonide Liquid Copper
(copper salts)
Tenn-Cop 5E (copper
salts)
Various brands of
sulfur
Maneb 80WP (maneb)
Maneb 75DF (maneb)
Manex 4F (maneb)
Applause 720 (chloro-
thalonil)
Equus, Echo 720 or
Chloronil 720 (chloro-
thalonil)
Echo 90DF or Equus DF
(chlorothalonil)
Bravo Ultrex (chloro-
thalonil)
Bravo Weather Stik
(chlorothalonil)
Iprodione 4L AG
Rovral 4F
(iprodione)


M1 2 Ibs


0.75 Ibs

1 lb

0.67 Ibs

2 Ibs

0.67 Ibs

1.25 Ibs


3 Ibs

1 tsp/gal

0.75 pts


M3 2 Ibs 12 Ibs 7
2 Ibs 12.8 Ibs 7
1.6 qts 9.6 qts 7
M5 1.5 pts 16 pts 7


Alternaria leaf spot
Black rot
Downy mildew


Powdery mildew

Alternaria leaf spot
Downy mildew


Alternaria leaf spot
Downy mildew


1.5 pts 16 pts 7


1.25 Ib 12 Ib 7

1.4 Ibs 14.5 Ibs 7

1.5 pts 16 pts 7


2 pts
(broc-
coli)
1 pt
(Chinese
mustard)


4 pts 0


Black leg
(Leptosphaeria maculans)
on broccoli;
Alternaria leafspot
(Alternaria spp.) on
Chinese mustard


Products are available for most
cole crops; High rates may
cause reddening or flecking
of older leaves. See labels for
details


Products are available for most
cole crops; See labels for details
Not labeled for collards, mus-
tard, turnip or watercress.
See labels for details

Not labeled for leafy cole crops
or watercress. See labels for
details


Only labeled for broccoli and
Chinese mustard. Limit is 2
appl for broccoli and 4 appl for
Chinese mustard. See labels for
details


Page 61







Vegetable Production Handbook


Table 10. Continued.

Fungicide Max. Rate/ Acre/ Min. Days
Chemical Code1 Applic. Season to Harvest Diseases or Pathogens Remarks2


Ridomil Gold SL
(mefenoxam)


Apron XL
(mefenoxam)


Ultra Flourish
(mefenoxam)
Ridomil Gold Bravo
(mefenoxam + chloro-
thalonil)
Ridomil Gold Bravo SC
(mefenoxam + chloro-
thalonil)
Endura (boscalid)





Switch 62.5WG
(cyprodinil + fludiox-
onil)


Amistar
(azoxystrobin)
Quadris
(azoxystrobin)
Cabrio EG (pyraclos-
trobin)


Reason 500SC
(Fenamidone)




Maxim 4FS


Terraclor 75WP,
Terraclor 15G (PCNB)

Aliette 80WG (fos-
etyl-al)


2 pts
(soil)
0.25 pts
(foliar)

See label


2 pts
(soil)
1 pt
(foliar)


4 pts 4 pts


4 + MS 1.5 lbs See label 7


4 + M5S


Pythium & Phytophthora
diseases (soil)
Downy mildew


Pythium & Phytophthora
diseases (soil)

Pythium & Phytophthora
diseases (soil)
Alternaria leaf spot
Downy mildew


1.5 pts See label 7


7 9 oz 18 oz 0 (head
and stem
brassicas)
14 (leafy
green bras-
sicas)
9 + 12 14 oz 56 oz 7


5 oz 30 oz 0


15.5floz 93floz


16 oz 64 oz 0


8.2 oz 24.6 oz 2


12 See label


See label 30 Ibs a.i.


33 5 Ibs


35 Ibs 3


Alternaria blight Gray mold
Sclerotinia rot
Powdery mildew
Rhizoctonia rot


Alternaria blight
Cercospora leaf spot
Powdery mildew


Alternaria leaf spot
Anthracnose
Black leg
Cercospora leaf spot
Downy mildew
Powdery mildew
Rhizoctonia blight
Ring spot
White rust
White leaf spot
Downy mildew
(Perenospora parasitica)
Cercospora leaf spot
(Cercospora brassicicola)
White rust (Albugo can-
dida)
Fusarium and Rhizoctonia
root rots


Clubroot
Rhizoctonia rot

Downy mildew


Not labeled for watercress; Use
only in a tank mix with another
effective fungicide
(non FRAC code 4). See label for
details
Seed treatment only; Not labeled
for watercress. See label for
details.
Soil applied as a preplant treat-
ment or following transplanting.
Not labeled for leafy cole crops
or watercress. Limit is 4 appli-
cations per crop. See labels for
details.



Not labeled for watercress; Limit
is 2 appl/crop. See label for
details.



No more than 2 sequential appl.
before rotating to a different
mode of action for at least 2
appl; 30 day plant back for off
label crops; See label for details
Not labeled for watercress; No
more than 1 sequential appl. See
label for details.


Not labeled for collards, kale,
mustard or watercress; No more
than 2 sequential appl/crop. See
label for details.


Not labeled for turnip or water-
cress. Limits are no more than
1 sequential appl. See label for
details.


Seed treatment only; Not labeled
for turnip or watercress. See
label for details.
Not labeled for leafy cole crops
or watercress. See label for
details.
Not labeled for turnip or water-
cress. Limit is 7 appl/crop. Do
not tank mix with copper fungi-
cides.


Page 62







Chapter 7: Cole Crop Production in Florida


Table 10. Continued.

Fungicide Max. Rate/ Acre/ Min. Days
Chemical Code1 Applic. Season to Harvest Diseases or Pathogens Remarks2


K-phite 7LP
Fosphite
Fungi-phite
Helena Prophyte
Phostrol
Topaz
(mono-and di-potassi-
um salts of phospho-
rous acid)
Forum
(dimethomorph)

Revus
(mandipropamid)


Presidio
(fluopicolide)





Actigard 50 WG
(acibenzolar-S-methyl)

Oxidate
(hydrogen dioxide)

Amicarb 100
Kaligreen
Milstop
(Potassium bicarbon-
ate)


Serenade ASO
Serenade Max
Sonata
(Bacillus sp.)


33 See label


40 6 oz 30 oz 0


40 8 fl oz 32 fl oz 1



43 4 fl oz 12 fl oz 2


1 oz 4 oz


1:100
dilution

See label


Biological
material


See label See label 0


Phythophthora spp.
Pythium spp. Fusarium
spp.
Rhizoctonia
Xanthomonas campestris
Anthracnose
Downy mildew
Powdery mildew

Downy mildew


Downy mildew



Downy mildew
Phytophthora spp.





Downy mildew Black rot
(Xanthomonas campestris;
suppression only)
Alternaria leaf spot
Downy mildew
Powdery mildew
Powdery mildew
Downy mildew
Alternaria leaf spot
Botrytis
Phoma blackleg and leaf-
spot
Anthracnose
Xanthomonas leaf spot
Alternaria leaf spot
Downy mildew
Powdery mildew


Not labeled for watercress. Do
not apply with copper based fun-
gicides. See label for details.







Not labeled for turnip or water-
cress. Limit is 5 appl. per
season.
Not labeled for turnip or water-
cress. Limit is no more than 2
sequential appl. or 4 total appl.
See label for details.
Not labeled for watercress. Limit
is no more than 2 sequential
appl. or 4 total appl. per season;
Use only in a tank mix with
another effective fungicide; 18
month plant back for off label
crops. See label for details.
Apply preventively; limit is 4
appl/crop on a 7-day schedule.
See label for details.
See label for details


See label for details


See label for details


1 FRAC code (fungicide group): Numbers (1-43) and letters (M, U, P) are used to distinguish the fungicide mode of action groups. All fungicides within the same group (with
same number or letter) indicate same active ingredient or similar mode of action. This information must be considered for the fungicide resistance management decisions.
M = Multi site inhibitors, fungicide resistance risk is low; U = Recent molecules with unknown mode of action; P = host plant defense inducers. Source: http://www.frac.info/
(FRAC = Fungicide Resistance Action Committee). Be sure to read a current product label before applying any chemicals.
2 Information provided in this table applies only to Florida. Be sure to read a current product label before applying any chemical. The use of brand names and any mention or
listing of commercial products or services in the publication does not imply endorsement by the University of Florida Cooperative Extension Service nor discrimination against
similar products or services not mentioned.


Page 63







Vegetable Production Handbook


Table 11. Selected insecticides approved for use on insects attacking cole crops.

Trade Name Rate REI Days To MOA
(Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes


Actara
(thiamethoxam)

Admire Pro
(imidacloprid)
(see appropriate
labels for other
brands)
Agree WG
(Bacillus thuringi-
ensis subspecies
aizawai)
*Ambush 25W3
(permethrin)


*Ammo 2.5 EC3
(cypermethrin)


*Asana XL (0.66
EC)3 (esfenvaler-
ate)


Assail 70WP
Assail 30SG
(acetamiprid)


Avaunt
(indoxacarb)


1.5-5.5 oz


12 0 -head & stem aphids, flea beetles, thrips, white-
7 leafy flies


4.4-10.5 fi oz 12 21


0.5-2.0 lb


3.2-6.4 oz
3.2-12.8 oz-
cabbage and
Chinese cab-
bage only


4 0


12 1


2.5-5.0 fi oz 12 1


2.9-9.6 fi oz
- head and
stem Brassicas,
5.8-9.6 oz
-collards, 9.6 -
mustard greens
0.8-1.7 oz
2.0-4.0 oz


2.5-3.5 oz


Aza-Direct 1-2 pts, up
azadirachtinn) to 3.5 pts, if
needed


Azatin XL
azadirachtinn)


5-21 fl oz


12 3-head & stem
7-collards,
mustard greens


12 7






12 3


4 0


4 0


aphids, leafhoppers, foliage-
feeding thrips, whiteflies


lepidopteran larvae (caterpillar
pests)


cabbage aphid (suppression),
cabbage looper, diamondback
moth3, imported cabbageworm


armyworms, crickets, cutworms,
corn earworm, loopers, Lygus
bug, flea beetles, imported cab-
bage worm, leafhoppers, salt-
marsh caterpillar, stink bugs, aids
in control of aphids and whiteflies
beet armyworm (aids in control),
cabbage looper, cutworms, flea
beetles, grasshoppers, imported
cabbageworm


aphids, thrips, whiteflies, sup-
pression of diamondback moth





beet armyworm, cabbage looper,
cabbage webworm, cross-striped
cabbageworm, diamondback
moth, imported cabbageworm


aphids, beetles, caterpillars,
leafhoppers, leafminers, thrips,
weevils, whiteflies
aphids, beetles, caterpillars,
leafhoppers, leafminers, thrips,
weevils, whiteflies


4A Do not use if other 4A
insecticide has been
applied.
4A Do not apply more than
0.38 Ib ai per acre per year.


11 Apply when larvae are
small for best control. Can
be used in greenhouse.
OMRI-listed2.
3 Do not apply more than
51.2 oz/acre per season.
Head and stem Brassica
crops only.


Maximum of 30 oz of prod-
uct/acre per season.


3 Do not apply more than 0.4
Ib ai/acre per season for
head and stem Brassicas
or 0.2 Ib ai/acre per season
for collards and mustard
greens.
4A Begin applications for
whiteflies when first adults
are noticed. Do not apply
more than 5 times per
season or apply more often
than every 7 days.
22 Do not apply more than 14
oz per acre per crop. Add
a wetting agent to improve
coverage. Do not use in
greenhouse or in crops
grown for transplant.
un Antifeedant, repellant,
insect growth regulator.
OMRI-listed2.
un Antifeedant, repellant,
insect growth regulator.


Page 64







Chapter 7: Cole Crop Production in Florida


Table 11. Continued.

Trade Name Rate REI Days To MOA
(Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes


*Baythroid XL
(beta-cyfluthrin)


Beleaf 50 SG
(flonicamid)


Biobit HP
(Bacillus thuringi-
ensis subspecies
kurstaki)

BotaniGard 22
WP, ES
(Beauveria bassi-
ana)


*Brigade 2 EC3
(bifenthrin)


Checkmate DBM-F
(pheromone)

Confirm 2F
(tebufenozide)


Coragen
(rynaxypyr)


Crymax WDG
(Bacillus thuringi-
ensis subspecies
kurstaki)


0.8-3.2 fl oz 12 0


2.0-2.8 oz


0.5-2.0 Ib


WP:
0.5-2 lb/100 gal
ES:
0.5-2 qts/100
gal


12 0


4 0


4 0


2.1-6.4 fl oz 12 7


3.1-6.2 fi oz


6-8 fl oz


0 0


4 7


3.5-5.0 fl oz 4 3


0.5-2.0 Ib


4 0


beet armyworm (1st & 2nd instar),
cabbage looper, cabbage web-
worm, cutworms, diamondback
moth larvae3, flea beetle, grass-
hoppers, imported cabbageworm,
potato leafhopper, southern
armyworm (1st & 2nd instar),
stink bugs, thrips, yellowstriped
armyworm
aphids, plant bugs


caterpillars (will not control large
armyworms)


aphids, thrips, whiteflies





aphids, armyworms, corn
earworm, crickets, cucumber
beetles, cutworms, diamond-
back moth, flea beetles, ground
beetles, imported cabbageworm,
leafhoppers, loopers, mites,
saltmarsh caterpillar, stink bugs,
thrips, tobacco budworm, whitefly
diamondback moth


armyworms, cabbage looper,
cabbage webworm, cross-striped
cabbageworm, garden webworm,
imported cabbageworm


beet armyworm, cabbage looper,
corn earworm, cross-striped
cabbageworm, diamondback
moth, Hawaiian beet webworm,
imported cabbageworm


caterpillars


Maximum per crop season:
12.8 fl oz/A.


9C Do not apply more than 8.4
oz/acre per season. Begin
applications before pests
reach damaging levels.
11 Treat when larvae are
young. Good coverage is
essential. Can be used in
the greenhouse.
OMRI-listed.
May be used in green-
houses. Contact dealer for
recommendations if an
adjuvant must be used. Not
compatible in tank mix with
fungicides.
3 Do not apply more than 0.4
Ib ai/acre for leafy or 0.5 Ib
ai/acre for head and stem.


For mating disruption.
Does not affect larvae and
eggs already on plants.
18 If diamondback moth is
also present another, or
an additional, insecticide
should be considered. Do
not exceed 56 ounces of
product per season.
28 For best results, use an
adjuvant when using as a
foliar spray. Can be applied
to soil at planting. See
label for diamondback
moth resistance manage-
ment.
11 Use high rate for army-
worms. Treat when larvae
are young.


Page 65







Vegetable Production Handbook


Table 11. Continued.


Trade Name Rate REI Days To MOA
(Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes


10.67-16 fl oz 24 7


0.25-1.5 Ib 4 0


AG500 pre-
plant: 1-4 qt
50W: 2-8 Ib


*Dibrom 8 EC
(naled)


Dimethoate 4 EC
(dimethoate)


*Dimilin 2L
(diflubenzuron)




DiPel DF
(Bacillus thuringi-
ensis subspecies
kurstaki)
*Di-Syston 8 EC
(disulfoton)

Durivo
(thiamethoxam,
chlorantraniliprole)
Entrust
(spinosad)


Esteem Ant Bait
(pyriproxyfen)


0.5-1 pt broc- 48
coli, cauliflower;
0.5 pt kale,
mustard greens


2-4 fl oz






0.5-2.0 Ib


1.1-2.1 fl
oz/1 000 ft of
row


96 preplant


48 1


7 broccoli,
cauliflower,
14 kale, mus-
tard greens


12 7






4 0


48 42


10-13 fl oz 12 30


0.5-3 oz


1.5-2.0 Ib


4 1


12 1


cabbage looper, imported cab-
bageworm, yellowstriped army-
worm


caterpillars


cutworms, mole crickets, wire-
worms


aphids, diamondback moth,
imported cabbageworm


aphids


grasshoppers






caterpillars


aphids, flea beetles, root aphids


aphids, caterpillars, flea beetles,
thrips, whiteflies

armyworms, cabbage looper, dia-
mondback moth, imported cab-
bageworm, leafminers, thrips


red imported fire ant


*Danitol3
(fenpropathrin)


Deliver
(Bacillus thuringi-
ensis subspecies
kurstaki)
*Diazinon AG-500,
*50 W
(diazinon)


3 Do not apply more than
42.67 fl oz per acre per
season. Head and stem
brassicas only.
11 Use higher rates for army-
worms. OMRI-listed2.


1B See label for crops (broc-
coli, cabbage, cauliflower,
collard, kale, mustard
greens). See label for
depth to incorporate.
1B Apply no more than 1 pt
per acre in Florida. Do not
apply more than 10 pt per
acre per season. See label
for crops not for all bras-
sicas.
1B Highly toxic to bees. For
broccoli, cauliflower, kale,
and mustard greens only.


15 All Brassica crops. No
more than 4 applications
per season. May be applied
only to turnip varieties that
do not produce a harvest-
able root.
11 Treat when larvae are
young. Good coverage is
essential. OMRI-listed2.

1B Cabbage and tight-heading
Chinese cabbage only soil
application.
4A, 28 May be applied via one of
several different soil appli-
cations methods.
5 See label for resistance
management. Do not apply
more than 9 oz per acre
per crop. OMRI-listed2.
7C Apply when ants are active-
ly foraging.


Page 66







Chapter 7: Cole Crop Production in Florida


Table 11. Continued.


Trade Name Rate REI Days To MOA
(Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes


Extinguish
((S)-methoprene)


Fulfill
(pymetrozine)


Intrepid 2F
(methoxyfenozide)


Javelin WG
(Bacillus thuringi-
ensis subspecies
kurstaki)


Knack
(pyriproxyfen)
Kryocide
(cryolite)


*Lannate LV; *SP
(methomyl)


*Larvin 3.2
(thiodicarb)


Lorsban 50 W,
75WG, (chlorpy-
rifos)


1.0-1.5 Ib


2.75 oz


4-16 fi oz,
depending on
pest


4 0


12 7


4 1


0.12-1.50 Ib 4 0


8-10 fl oz

8-16 Ib


LV: 0.75-3.0 pt
SP: 0.25-1 Ib


fire ants


cabbage aphid, green peach
aphid, turnip aphid, whiteflies


beet armyworm, cabbage looper,
cabbageworm, cross-striped
cabbageworm, fall armyworm
garden webworm, imported cab-
bageworm, southern armyworm,
true armyworm, yellowstriped
armyworm
most caterpillars, but not
Spodoptera species armywormss)


12 7 whiteflies (immatures)

12 depends on cabbage looper, cutworms, dia-
crop 7-14 mond back moth, flea beetles,
imported cabbage worm, yellow-
striped armyworm


48 Cabbage -1,
broccoli and
cauliflower 3,
others -10


16-40 fl oz 48 7


50W: 2 Ib
75WG:
0.67-1.33 Ib


24 21

72 for
cauli-
flower


Beet armyworm, diamondback
moth, fall armyworm, imported
cabbageworm, loopers, varie-
gated cutworm (pests vary by
specific crop)


beet armyworm, cabbage looper,
diamondback moth, flea beetles,
imported cabbageworm


armyworms, beet armyworm,
cabbage aphid, cutworms, flea
beetles, imported cabbageworm


7A Slow-acting IGR (insect
growth regulator). Best
applied early spring and fall
where crop will be grown.
Colonies will be reduced
after three weeks and elim-
inated after 8 to 10 weeks.
May be applied by ground
equipment or aerially.
9B Apply when aphids and
whiteflies first appear.
Provides suppression of
whiteflies. Maximum of 2
applications per crop.
18 Do not apply more than 64
oz per acre per season.


11 Treat when larvae are
young. Thorough coverage
is essential. OMRI-listed2.
See label for crops (most
cole crops).
7C Limited to 2 applications
per season.
un Do not exceed 96 Ib per
acre per season. (broccoli,
cabbage, cauliflower, col-
lards, kohlrabi)
1A Do not make more than 10
applications per crop (8 for
collards, kale, mustard and
turnip greens). For use on
broccoli, cabbage, cauli-
flower, Chinese cabbage,
fresh market collards, kale,
mustard and turnip greens.
1A Do not exceed more than
4.0 Ib active ingredient per
acre per season. (160 fl oz)
For broccoli, cabbage, and
cauliflower only.
1B For use on broccoli, cab-
bage, cauliflower, collards,
kale, kohlrabi. See label for
specific crop directions.


Page 67







Vegetable Production Handbook


Table 11. Continued.


Trade Name Rate REI Days To MOA
(Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes


Lorsban 15G,
75WG, Advanced


Malathion 8F
(malathion)
Movento
(spirotetramat)
M-Pede 49% EC
(soap, insecticidal)
*MSR Spray
Concentrate
(oxydeme-
ton-methyl)
*Mustang
(zeta-cypermethrin)








Neemix 4.5
azadirachtinn)


Oberon 2 SC
(spiromesifen)


See labels for 24, 72
rates for cauli-
flower


1.5-2.5 pt

4-5 fl oz

1-2 % VN

1.5-2 pt


21, except cau-
liflower (30)


12 7, except broc-
coli (3)
24 1


12 0

7 days 7


2.4-4.3 oz 12 1


4-16 fl oz


12 0


7.0-8.5 fi oz 12 7


root maggots. If preplant
(Lorsban Advanced), also bill-
bugs, cutworms, grubs, symphy-
lans, wireworms


1B Only one application per
season. See label for
restrictions and specific
crop directions.


aphids, cabbage looper, imported 1B
cabbageworm


aphids, whiteflies


aphids, leafhoppers, mites, thrips,
whiteflies
aphids, thrips


aphids (some), armyworms,
cabbage looper, cabbage web-
worm, corn earworm, crickets,
cucumber beetles, cutworm, flea
beetles, grasshoppers, imported
cabbageworm, leafhoppers,
saltmarsh caterpillar, southern
cabbageworm, stink bugs, aids in
control of whiteflies
aphids, armyworms, cabbage
looper, caterpillars, cutworms,
diamondback moth, dipterous
leafminers, leafminers, imported
cabbageworm, thrips, whiteflies
whiteflies


23 Limited to 10 oz/acre per
season.
OMRI-listed2.

1B Broccoli, cabbage, cau-
liflower See label for
restrictions.

3 Do not make applications
less than 7 days apart.
Diamondback moth popu-
lations in Florida have been
found to be resistant to
pyrethroids.



un IGR and feeding repellant.
Greenhouse and field.
OMRI-listed2.


23 Maximum amount per
crop: 25.5 fl oz/acre. No
more than 3 applications.


Platinum
Platinum 75SG
(thiamethoxam)
*Pounce 25 WP3
(permethrin)

*Proaxis
Insecticide3
(gamma-cyhalot-
hrin)


5.0-11 fl oz
1.66-3.67 oz

See label for
crop-specific
rates.
1.92-3.84 fI oz


12 30


12 1


24 1


aphids, flea beetles, thrips, white- 4A
flies

armyworms, cabbage looper, dia- 3
mondback moth, imported cab-
bageworm, plant bugs, thrips
aphids(2), armyworm, beet army- 3
worm(1), cabbage looper, cab-
bage webworm, corn earworm,
cutworms, diamondback moth,
fall armyworm(1), flea beetles,
grasshoppers, imported cabbage-
worm, leafhoppers, southern cab-
bageworm, spider miteS(2), stink
bugs, thrips(2), vegetable weevil
(adult), whiteflies(2), yellowstriped
armyworm


Soil application.


Broccoli, cabbage, cauli-
flower, Chinese broccoli,
collards, turnips
(1) First and second instars
only.
(2)Suppression only.
Do not apply more than
1.92 pints per acre per sea-
son.


Head and stem brassicas
only.


Page 68







Chapter 7: Cole Crop Production in Florida


Table 11. Continued.


Trade Name Rate REI Days To MOA
(Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes


*Proclaim
(emamectin benzo-
ate)


Provado 1.6F (imi- 3.8 oz
dacloprid)


Pyganic 5.0
(pyrethrins)

Pyrellin EC3
(pyrethrins + rote-
none)

Radiant SC
(spinetoram)


Requiem 25EC
(extract of
Chenopodium
ambrosioides)
Rimon 0.83 EC
(novaluron)


2.4-4.8 oz 12 7 head &
stem

14 leafy


12 7


12 0


12 12 hours



4 1


4.5-18 oz


1-2 pt



5-10 fl oz


2-4 qt (no more 4
than 2% v/v)


6-12 fl oz


12 7


beet armyworm, cabbage
webworm, corn earworm,
cross-striped cabbageworm, dia-
mondback moth, fall armyworm,
imported cabbageworm, loopers,
suppression of leafminers


aphids, whiteflies


insects


aphids, dipterous leafminers, flea
beetles, leafhoppers, leafminers,
loopers, Lygus bug, mites, plant
bugs, thrips, whiteflies
armyworms, cabbage looper,
diamondback moth, imported
cabbageworm, Liriomyza leafmin-
ers, thrips


green peach aphid, turnip aphid, un
whiteflies


armyworms, cabbage looper, cab- 15
bage webworm, corn earworm,
cucumber beetles, diamondback
moth, imported cabbageworm,
lepidopteran and dipteran leaf-
miners, stink bugs, vegetable
weevil, suppression of: thrips,
whiteflies


6 Do not make more than
2 sequential applications
without rotating to another
product with a different
mode of action. Do not
apply by aircraft. Not for
turnips grown for roots.
4A Do not apply more than 0.5
Ib ai per year.
3 Harmful to bees. Can be
used in greenhouses.
OMRI-listed.2
3, 21B Harmful to foraging bees.



5 Do not apply to seedlings
grown for transplant.


No more than 3 applica-
tions per season. Head and
stem Brassica only.


Saf-T-Side, others
(Oil, insecticidal)
Sevin 80S; XLR,
4F (carbaryl)


1-2 gal/100 gal 4

80S: 0.63-2.5 Ib 12
XLR, 4F:
0.5-2 qts


up to day of aphids, leafhoppers, mites, plant
harvest bugs, thrips, whiteflies


3 or 14,
depending on
specific crop


armyworms, corn earworm,
diamondback moth, flea beetles,
harlequin bug, imported cabbage
worm, leafhoppers


OMRI-listed2.


1A Up to 4 applications, at
least 7 days apart. See
label for specific crops.


SpinTor 2 SC
(spinosad)


Synapse
(flubendiamide)
*Telone C-35
(dichloropropene +
chloropicrin)


3-10 fl oz


4 1


12 1


See label


5 days
- See
label


armyworms, cabbage looper, dia- 5
mondback moth, imported cab-
bageworm, leafminers, thrips


armyworms, diamondback moth, 28
imported cabbageworm, loopers


preplant


symphylans, wireworms


Do not apply to cole crops
grown within a greenhouse
or screenhouse for trans-
plant. Do not make more
than 2 consecutive applica-
tions.
Do not apply more than 4
oz/acre per season.


See supplemental label for
use restrictions for south
and central Florida.


Page 69







Vegetable Production Handbook


Table 11. Continued.


Trade Name Rate REI Days To MOA
(Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes
*Telone II
(dichloropropene)


*Thionex 3EC
endosulfann)


1-1.33 qt


*Thionex 3EC 1-1.33 qt,
endosulfann) except kale (1
qt)


Trigard
(cyromazine)


2.66 oz


Trilogy 0.5-2% VN
(extract of neem
oil)


Venom Insecticide foliar: 1-4 oz
(dinotefuran) soil: 5-6 oz


96 broccoli and
cabbage 7,
cauliflower 14


48 21


12 7


4 0


12 foliar 1
soil 21


armyworms, cabbage aphid, cab-
bage looper, cross-striped cab-
bageworm, cutworms, diamond-
back moth, flea beetles, harlequin
bug, imported cabbageworm,
leafhoppers, stink bugs, whiteflies
armyworms, aphids, cabbage
looper, diamondback moth, flea
beetles, harlequin bug, imported
cabbageworm, whitefly


leafminers


aphids, mites, suppression of
thrips and whiteflies



cabbage aphid, green peach
aphid, leafminer, whiteflies


Venom 20 SG foliar: 0.44-
0.895 Ib
soil: 1.13-1.34
Ib


Voliam Flexi
(thiamethoxam and
chlorantraniliprole)



*Warrior II3
(lambda-cyhalot-
hrin)


Xentari DF
(Bacillus thuringi-
ensis subspecies
aizawai)


4-7 oz


12 head and
stem 3, leafy
Brassica greens
-7


0.96-1.92 fl oz 24


0.5-2.0 Ib 4 0


aphids, beet armyworm, cabbage
looper, cabbage webworm, corn
earworm, diamondback moth, fall
armyworm, flea beetles, imported
cabbageworm, thrips, whitefly,
yellowstriped armyworm
aphids(1), beet armyworm(2),
cabbage looper, cabbage web-
worm(1), corn earworm, cut-
worms, diamondback moth, fall
armyworm(2), flea beetles, grass-
hoppers, imported cabbageworm,
leafhoppers, mites(1), plant bugs,
stink bugs, thrips, whiteflies(t),
yellowstriped armyworm
caterpillars


Do not make more than 2
applications per season or
exceed 2.0 Ib ai/acre per
season. For broccoli, cab-
bage, cauliflower.


2 Do not make more than
one application per season
or apply more than 1.0 Ib
ai/acre per season (0.75
Ib for kale). For collards,
mustard greens, kale.
17 Limited to 6 applications.

un Apply morning or evening
to reduce potential for
leaf burn. Toxic to bees
exposed to direct treat-
ment. OMRI-listed2.
4A Use one application meth-
od, not both (soil or foliar).
Foliar: Do not apply more
than 0.268 Ib ai per acre
per season.
Soil: Do not apply more
than 0.536 Ib ai per acre
per season.

For head and stem bras-
sicas only.
4A, 28 Highly toxic to bees
exposed to direct treatment
or residues on blooming
crops.


3 Do not apply more than
0.24 Ib ai/acre per season.

(1) suppression only
2) 1st and 2nd instar only

For head and stem
Brassicas only.

11 Treat when larvae are
young. Thorough coverage
is essential. May be used
in the greenhouse. Can be
used in organic production.


Page 70







Chapter 7: Cole Crop Production in Florida


Table 11. Continued.

Trade Name Rate REI Days To MOA
(Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes
The pesticide information presented in this table was current with federal and state regulations at the time of revision. The user is
responsible for determining the intended use is consistent with the label of the product being used. Use pesticides safely. Read and
follow label instructions.
1Mode of Action codes for vegetable pest insecticides from the Insecticide Resistance Action Committee (IRAC) Mode of Action
Classification v. 6.1 August 2008.
1A. Acetyl cholinesterase inhibitors, Carbamates (nerve action)
1 B. Acetyl cholinesterase inhibitors, Organophosphates (nerve action)
2A. GABA-gated chloride channel antagonists (nerve action)
3. Sodium channel modulators (nerve action)
4A. Nicotinic acetylcholine receptor agonists (nerve action)
5. Nicotinic acetylcholine receptor allosteric activators (nerve action)
6. Chloride channel activators (nerve and muscle action)
7A. Juvenile hormone mimics (growth regulation)
7C. Juvenile hormone mimics (growth regulation)
9B and 9C. Selective homopteran feeding blockers
10. Mite growth inhibitors (growth regulation)
11. Microbial disruptors of insect midgut membranes
12B. Inhibitors of mitochondrial ATP synthase (energy metabolism)
15. Inhibitors of chitin biosynthesis, type 0, lepidopteran (growth regulation)
16. Inhibitors of chitin biosynthesis, type 1, homopteran (growth regulation)
17. Molting disruptor, dipteran (growth regulation)
18. Ecdysone receptor agonists (growth regulation)
22. Voltage-dependent sodium channel blockers (nerve action)
23. Inhibitors of acetyl Co-A carboxylase (lipid synthesis, growth regulation)
28. Ryanodine receptor modulators (nerve and muscle action)
un. Compounds of unknown or uncertain mode of action

2 OMRI-listed: Listed by the Organic Materials Review Institute for use in organic production.
3 Diamondback moth in Florida has been found to be resistant to pyrethroids.
* Restricted Use Only.


Page 71







Vegetable Production Handbook


Table 12. Selected insecticides approved for use on insects attacking turnips.


Trade Name Rate REI Days To MOA
(Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes
Actara 1.5-4.0 oz 12 7 aphids. flea beetles, leaf- 4A Use higher rate for whiteflies.


(thiamethoxam)


Admire Pro
(imidacloprid)
Agree WG
(Bacillus thuringiensis
subspecies aizawai)
*Ambush 25W2
(permethrin)


*Asana XL (0.66 EC)
(esfenvalerate)
Aza-Direct
azadirachtinn)


Azatin XL
azadirachtinn)


*Baythroid XL2
(beta-cyfluthrin)


Biobit HP
(Bacillus thuringiensis
subspecies kurstaki)

BotaniGard 22 WP, ES
(Beauveria bassiana)



Checkmate DBM-F
(pheromone)


Confirm 2F
(tebufenozide)


hoppers, whiteflies


4.4-10.5 fi oz 12 21 aphids, flea beetles, leaf-
hoppers, thrips, whiteflies


0.5-2.0 Ib


3.2-6.4 oz


4 0 lepidopteran larvae (cater- 11
pillar pests)

12 1 cabbage aphid (suppres- 3
sion), cabbage looper, dia-
mondback moth (larvae),
imported cabbageworm


5.8-9.6 fl oz 12 7 armyworm, flea beetles,
imported cabbageworm


1-2 pts, up
to 3.5 pts, if
needed

5-21 fl oz


4 0 aphids, beetles, caterpil-
lars, leafhoppers, leafmin-
ers, mites, stink bugs,
thrips, weevils, whiteflies
4 0 aphids, beetles, caterpil-
lars, leafhoppers, leaf-
miners, thrips, weevils,
whiteflies


0.8-3.2 fl oz 12 0 beet armyworm (1st & 2nd 3
instar), cabbage looper,
cabbage webworm, cut-
worms, diamondback
moth larvae, fall army-
worm (1st & 2nd instar),
grasshoppers, imported
cabbageworm, southern
armyworm (1st & 2nd
instar), thrips, yellow-
striped armyworm


0.5-2.0 Ib


WP:
0.5-2 lb/100 gal
ES:
0.5-2 qt/100 gal


4 0 caterpillars (will not con-
trol large armyworms)


4 0 aphids, thrips, whiteflies


3.1-6.2 fl oz 0 0 diamondback moth


6-8 fl oz


4 7 armyworms, cabbage
looper, cabbage web-
worm, cross-striped
cabbageworm, garden
webworm, imported cab-
bageworm


For turnips grown for roots. Do
not exceed 8 oz/acre per season.
One application, no more than
10.5 oz/acre.
Apply when larvae are small for
best control.

Do not exceed 4 applications.
For turnips grown for roots.


Do not apply more than 0.4 Ib ai
per acre per season.
Antifeedant, repellant, insect
growth regulator. OMRI-listed3.


Antifeedant, repellant, insect
growth regulator.


Maximum amount per season -
12.8 fl oz/A.

Note: For turnip greens only, not
roots.


11 Treat when larvae are young.
Good coverage is essential. Can
be used in the greenhouse.
OMRI-listed3.
May be used in greenhouses.
Contact dealer for recommen-
dations if an adjuvant must be
used. Not compatible in tank
mix with fungicides.
For mating disruption. Does not
affect eggs and larvae already
on plants.
18 If diamondback moth is also
present another, or an addi-
tional, insecticide should be
considered. Do not exceed 56
ounces of product per acre per
season.


Page 72







Chapter 7: Cole Crop Production in Florida


Table 12. Continued.


Trade Name Rate REI Days To MOA
(Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes


Crymax WDG
(Bacillus thuringiensis
subspecies kurstaki)
Deliver
(Bacillus thuringiensis
subspecies kurstaki)
Dimethoate 4EC
(dimethoate)

Dimilin 2L
(diflubenzuron)




DiPel DF
(Bacillus thuringiensis
subspecies kurstaki)
Entrust
(spinosad)


Extinguish
((S)-methroprene)


Fulfill
(pymetrozine)


Intrepid 2F
(methoxyfenozide)


0.5-2.0 Ib


4 0 caterpillars


0.25-1.5 Ib 4 0 caterpillars


4EC: 0.5 pt 48 14 -
greens &
roots


2-4 oz





0.5-2.0 Ib


0.5-3.0 oz
(greens)

1.0-2.0 oz
(roots)
1.0-1.5 Ib


2.75 oz


4-8 fl oz if
grown for
greens
6-16 fl oz if
grown for roots


11 Use high rate for armyworms.
Treat when larvae are young.

11 Use higher rates for army-
worms. OMRI-listed3.


aphids, leafhoppers, leaf-
miners


12 7 grasshoppers





4 1 caterpillars


4 1 armyworms, cabbage
greens looper, diamondback
moth, imported cabbage-
3 roots worm, leafminers, thrips


4 0 fire ants


12 7 cabbage aphid, green
peach aphid, turnip aphid,
whiteflies


4 1 -
greens
14 roots


beet armyworm, cabbage
looper, cabbageworm,
cross-striped cabbage-
worm, fall armyworm
garden webworm,
imported cabbageworm,
southern armyworm, true
armyworm, yellowstriped
armyworm


Highly toxic to bees.


15 Dimilan is an insect growth
regulator insects must ingest
and molt before effects are seen.
Apply when grasshoppers are
in the 2nd to 3rd nymphal stage.
Turnip greens only.
11 Treat when larvae are young.
Good coverage is essential.
OMRI-listed3.
5 Do not apply to cole crops
grown within a greenhouse or
screenhouse for transplant.
OMRI-listed3.

7A Slow-acting IGR (insect growth
regulator). Best applied early
spring and fall where crop will
be grown. Colonies will be
reduced after three weeks and
eliminated after 8 to 10 weeks.
May be applied by ground
equipment or aerially.
9B Apply when aphids and white-
flies first appear. Provides sup-
pression of whiteflies. Maximum
of 2 applications per crop.
Greens only.
18 Do not apply more than 64 oz
per acre per season.


Javelin WG
(Bacillus thuringiensis
subspecies kurstaki)
*Lannate LV, *SP (meth-
omyl)


Lepinox WDG
(Bacillus thuringiensis
subspecies kurstaki)


0.12-1.50 Ib 4 0 most caterpillars, but
not Spodoptera species
armywormss)


LV: 1.5-3.0 pt
SP: 0.5-1.0 lb


1.0-2.0 Ib


48 10 beet armyworm, cabbage
looper, cabbageworm, dia-
mondback moth (larvae),
imported cabbageworm
12 0 for most caterpillars,
including beet armyworm
(see label)


11 Roots only. Treat when larvae
are young. Thorough coverage
is essential. OMRI-listed3.


Greens only.


11 Treat when larvae are small.
Thorough coverage is essential.


Page 73







Vegetable Production Handbook


Table 12. Continued.


Trade Name Rate REI Days To MOA
(Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes


Lorsban 15 G, 75G
(chlorpyrifos)
M-Pede 49% EC
(Soap, insecticidal)

Neemix 4.5 EC
azadirachtinn)




Platinum
75SG
(thiamethoxam)
*Pounce 25 WP (per-
methrin)


*Proclaim
(emamectin benzoate)


See labels for
rates
1-2% VN


4-16 fl oz





5-12 fl oz
1.7-4.01 oz

3.2-9.6 oz


2.4-4.8 oz


at plant-
ing


root maggots


12 0 aphids, leafhoppers,
mites, plant bugs, thrips,
whiteflies
12 0 aphids, armyworms, cab-
bage looper, cutworms,
diamondback moth (lar-
vae), imported cabbage-
worm, leafminers, thrips,
whiteflies
12 at plant- aphids, flea beetles, leaf-
ing hoppers, whiteflies

12 1 aphids (suppression),
armyworms, beet army-
worm, cabbage looper,
corn earworm, cutworms,
diamondback moth
(larvae), fall armyworm,
imported cabbageworm,
leafhoppers, leafminers,
southern armyworm,
southern white butterfly
12 14 beet armyworm, cabbage
webworm, corn earworm,
cross-striped cabbage-
worm, diamondback
moth, fall armyworm,
imported cabbageworm,
cabbage looper, suppres-
sion of Liriomyza leafmin-
ers


1 B One application per season.

-- OMRI-listed2.


un IGR and feeding repellant.
Greenhouse and field use.
OMRI-listed3.



4A Do not exceed a total of 12 fl oz
per acre per season or 4.01 oz
(75SG).

3 Roots only. Do not apply more
than 0.45 Ib ai/acre per season.


Greens only.


Provado 1.6F
(imidacloprid)


Pyrellin EC
(pyrethrin + rotenone)

Radiant
(spinetoram)


SpinTor 2 SC
(spinosad)


Sulfur 80% W, others
*Telone C-35 (dichloro-
propene + chloropicrin)


3.5 oz


1-2 pt


6-8 roots
5-10 tops


3-6 fl oz



See label
See label


12 7 aphids, flea beetles, white- 4A
flies

12 12 hours aphids, leafhoppers, leaf- 3
miners, loopers, mites,
plant bugs, thrips
4 3 armyworms, diamondback 5
moth, imported cabbage-
worm, Liriomyza leafmin-
ers, loopers, thrips


4 1 tops armyworms, cabbage
looper, diamondback
3 roots moth, imported cabbage-
worm, leafminers, thrips


24
5 days
- See
label


mites
preplant symphylans, wireworms --


Do not use in conjunction with
Admire. Maximum of 10.5 fl oz.
per acre per season.


See label.


5 Do not apply to cole crops
grown within a greenhouse or
screenhouse for transplant.


See supplemental label for use
restrictions in south and central
Florida.


Page 74







Page 75


Chapter 7: Cole Crop Production in Florida


Table 12. Continued.


Trade Name Rate REI Days To MOA
(Common Name) (product/acre) (Hours) Harvest Insects Code1 Notes

*Telone II
(dichloropropene)

Trigard 2.66 oz 12 7 leafminers 17 Limited to 6 applications. Turnip
(cyromazine) greens only.
Trilogy 0.5-2.0% V/V 4 0 aphids, mites, suppres- un Apply morning or evening to
(extract of neem oil) sion of thrips and white- reduce potential for leaf burn.
flies Toxic to bees exposed to direct
treatment. OMRI-listed3.
Xentari DF 0.5-2.0 Ib 4 0 caterpillars 11 Treat when larvae are young.
(Bacillus thuringiensis Thorough coverage is essential.
subspecies aizawal) May be used in the greenhouse.
Can be used in organic produc-
tion.
The pesticide information presented in this table was current with federal and state regulations at the time of revision. The user is
responsible for determining the intended use is consistent with the label of the product being used. Use pesticides safely. Read and
follow label instructions.
1 Mode of Action codes for vegetable pest insecticides from the Insecticide Resistance Action Committee (I RAC) Mode of Action Classification v. 6.1 August 2008.

1A. Acetylcholinesterase inhibitors, Carbamates (nerve action)
1B. Acetylcholinesterase inhibitors, Organophosphates (nerve action)
2A. GABA-gated chloride channel antagonists (nerve action)
3. Sodium channel modulators (nerve action)
4A. Nicotinic acetylcholine receptor agonists (nerve action)
5. Nicotinic acetylcholine receptor allosteric activators (nerve action)
6. Chloride channel activators (nerve and muscle action)
7A. Juvenile hormone mimics (growth regulation)
7C. Juvenile hormone mimics (growth regulation)
9B and 9C. Selective homopteran feeding blockers
10. Mite growth inhibitors (growth regulation)
11. Microbial disruptors of insect midgut membranes
12B. Inhibitors of mitochondrial ATP synthase (energy metabolism)
15. Inhibitors of chitin biosynthesis, type 0, lepidopteran (growth regulation)
16. Inhibitors of chitin biosynthesis, type 1, homopteran (growth regulation)
17. Molting disruptor, dipteran (growth regulation)
18. Ecdysone receptor agonists (growth regulation)
22. Voltage-dependent sodium channel blockers (nerve action)
23. Inhibitors of acetyl Co-A carboxylase (lipid synthesis, growth regulation)
28. Ryanodine receptor modulators (nerve and muscle action)
un. Compounds of unknown or uncertain mode of action
2 Avoid pyrethroids if diamondback moth is a problem. Larvae have been shown to be resistant.

3 OMRI listed: Listed by the Organic Materials Review Institute for use in organic production.

Restricted Use Only.






Page 76


Table 13. Breakeven production costs for cabbage at various yield levels in the Hastings, FL area, 2008-2009.

Yield (50 Ib units/acre)
Cost per acre 660 680 700 720 740
Variable Costs $1,386.85 $2.10 $2.04 $1.98 $1.93 $1.87
Fixed Costs $531.66 $0.81 $0.78 $0.76 $0.74 $0.72
Harvest Cost/unit $2.73 $2.73 $2.73 $2.73 $2.73
Total Cost/unit $5.64 $5.55 $5.47 $5.39 $5.32


Vegetable Production Handbook






UF UNIVERSITY of
UFFLORIDA
IFAS Extension
Chapter 8. 2010-2011

Production of Major Asian Vegetable Production in Florida

M.L. Lamberts, E.J. McAvoy, D.D. Sui, A.J. Whidden and C.A. Snodgrass


The term "Asian Vegetable" is a broad one which
encompasses both the vegetables grown in the countries
that comprise Asia and those eaten by people of Asian
extraction or who like Asian cuisine. Since many of the
vegetables which are described in this chapter are members
of families that are covered in depth in other chapters in
this volume, that information will not be duplicated.


CRUCIFERS
This group (Tables la and ib) includes primarily crops
with edible leaves, with the exception of kohlrabi where
the swollen stem is consumed and daikon which is an edi-
ble root. They can be grown on raised beds without mulch
(or with mulch if it is cost effective) and with either drip
or subsurface irrigation. Fertilizer recommendations for
these crops are found in Chapter 7 under broccoli, cabbage
or Chinese cabbage, except for daikon which is in Chapter
18. For pest control products, these crops are included
in Crop Group 5 [Brassica (Cole) Leafy Vegetables]. The
exception is daikon, which is in Crop Group 1 (Root and
Tuber Vegetables) and is covered in Chapter 18.


BOTANY


Nomenclature
Family Brassicaceae (Cruciferae)

Cabbage, flat Brassica oleracea var. capitata

Chinese broccoli / gailan or gai lan / kailan or kai lan /
flowering kale Brassica oleracea var. alboglabra

Chinese cabbage [includes: napa (tight headed) and chi-
hili (semi-loose headed)]- Brassica rapa var. pekinensis

Chinese mustard (includes: bok choi Shanghai choi
/ baby bok choi, yuchoi / yuchoy / u-choi /choy sum -
Brassica rapa subsp. chinensis

Kohlrabi Brassica oleracea var. gongylodes

Oriental radish: Daikon (Japanese) / lobok or lo bok
(Chinese) Raphanus sativus var. longipinnatus


CUCURBITS

This group (Tables 2a and 2b) includes, eaten either
immature or mature, and several vegetables with edible
tender stems and leaves. All can be grown on raised beds,
with or without plastic mulch, and with either drip or sub-
surface irrigation. Most of the crops are trellised, primar-
ily to produce straight fruit, winter melon is the exception
since it is generally too heavy to trellis. Fertilizer recom-
mendations for cucumbers (Chapter 9) are applicable for
fuzzy melon, long gourd, both luffas, bittermelon and
snake gourd. Recommendations for watermelon (Chapter
9) should be followed for winter melon and chayote. With
the exception of chayote, where the entire fruit is planted,
these crops are started from seed and grown as transplants
prior to being set in the field. For pest control prod-
ucts, these crops are included in Crop Group 9 (Cucurbit
Vegetables).


BOTANY
Nomenclature
Bittermelon (Chinese and Indian types) Momordica
charantia (Fig. 8-1)


Chayote Sechium edule (Fig. 8-2)


Fuzzy melon (immature fruit) and winter melon (mature
fruit) Benincasa hispida

Long gourd (oopoh) Lagenaria siceraria

Angled luffa (silk squash) Luffa acutangula

Smooth luffa Luffa aegyptica cylindricaa)

Snake gourd Trichosanthes cucumerina


Page 77







Vegetable Production Handbook


Table la. Varieties of Asian Brassicas


Crop
Cabbage, flat
Chinese broccoli / gailan / flowering kale
Chinese cabbage
napa (tight-headed)
chihili [semi-loose headed]
Chinese mustard
bok choi
Shanghai choi/baby bok choi
yuchoi / yuchoy / u-choi /choy sum
Kohlrabi
Oriental radish


Varieties
Drumhead, KK Cross, KY Cross
Green Lance


China Express, China Pride
Michihili, Monument, Jade Pagoda


Canton Choice, Ching-Chiang, Hybrid Lucky choi, Long White, Short White
Dynasty, Shanghai Green
Dwarf, Extra Dwarf,
Peking, Purple
Daikon (Japanese): Everest, Hybrid Everest, Mikura Cross, Mino Early, Relish
Lobok / lo bok (Chinese): Red Meat


Table 1b. Seeding and Planting Information for Asian Brassicas


Planting dates
North Florida
Central Florida
South Florida
Seeding information
Number of rows/44-inch wide
beds (6 ft centers)
Distance between rows (in)

Distance between plants (in)



Seeding depth (in)
Seed per acre (lb)
Days to maturity from seed
Plant populations (acre)


Chinese broccoli
Aug Feb
Sept- Apr
Sept- Apr


Chinese cabbages
Aug Feb
Sept- Apr
Sept- Apr


14 or 24


14-18


0.25-0.5



116,160


0.25-0.5



18,671


Chinese mustards
Aug Feb
Sept- Apr
Sept- Apr


4

14 mustard
11 -others (below)
12-18 mustard
8-12 Shanghai/choy sum
6-10 baby bok choy
2-4 u-choy
0.25-0.5



29,040 mustard
43,560 Shanghai/choy sum
58,080 baby bok choy
174,240 u-choy


Daikon
Sept- Mar
Sept- Apr
Sept- Apr


3 (fall/spring) to
4 (winter)
11

6-9



0.25



58,080


Page 78







Page 79


Chapter 8: Production of Major Asian Vegetable Production in Florida


Table 2a. Varieties and Trellising Requirements of Asian Cucurbits


Crop
Bittermelon Chinese
Bittermelon Indian
Chayote (short lived perennial)

Fuzzy melon
Long gourd
Angled luffa
Smooth luffa
Snake gourd
Winter melon


Varieties
Chinese: Hong Kong Green, Hybrid Bangkok Large, Japan Green Sprinkle, Taiwan Large
Indian: Hybrid India Star NS, India Green Queen, India long Green
The seed is the viviparous fruit itself. There is some debate as to whether varieties remain
true
Chiang Shin Joker, Seven Star Long
Hybrid India Long, Hybrid Asia Short
Hybrid Green Glory, Lucky Boy, Summer Long
Smooth Beauty, Smooth Boy
Extra Long Dancer, Hybrid Snaky, Long EX
Hybrid Asia Sweet, Hybrid Red Doll, Hybrid Wonder Wax


Trellising


Table 2b. Seeding, Planting Information for Asian Cucurbits


Planting dates
North Florida

Central Florida


Bittermelon
Feb Apr;
July-Aug
Jan Mar;
Sept


Long gourd
Feb Apr;
July-Aug
Jan Mar;
Sept


Angled luffa
Feb Apr;
July-Aug
Jan Mar;
Sept


Smooth luffa
Feb Apr;
July-Aug
Jan Mar;
Sept


South Florida Sept Feb Sept Feb Sept Feb Sept Feb
Seeding information
Distance between rows (in) 60 72 60 72 60 72 60 72
Distance between plants (in) 36 60 36 60 36 60 36 60
Seeding depth (in)
Seed per acre
Days to maturity from seed 80 100
Days to maturity from transplant
Plant populations (acre) 2904 2904 2904 2904
Planting dates Fuzzy melon Snake gourd Chayote1 Winter melon
North Florida Feb Apr; Feb Apr; Not recommended Feb 15 Apr 15
July Aug July Aug
Central Florida Jan Mar; Jan Mar; Not recommended Jan 15 Mar 15
Sept Sept
South Florida Sept Feb Sept Feb Sept Feb Dec 15 Mar 1
Seeding information
Distance between rows (in) 60-72 60-72 60-72 72 108
Distance between plants (in) 36 60 36 60 36 60 60 72
Seeding depth (in) 1.5- 2.0 1.5 2.0 Whole fruit is used 1.5 2.0
should be covered half way
Seed per acre 2904 whole fruit
Days to maturity from seed
Days to maturity from transplant
Plant populations (acre) 2904 2904 2904 1452
Chayote flowers and sets fruit under short day conditions and lives for a few years, so it is not recommended for areas where freezing temperatures are likely to occur on an
annual basis.







Vegetable Production Handbook


LEGUMES

The Asian legume group (Tables 3a and 3b) includes
fruits (usually known as pods), which are eaten at the
immature stage, crop with edible immature seeds (green
shell), and stem tips. The winged bean also has edible
leaves and roots, though the latter do not appear to be cul-
tivated commercially in the Continental U.S. All the pole
or indeterminate types can be grown on raised beds with-
out mulch using either drip, overhead or subsurface irriga-
tion. Fenugreek does not grow well in rocky soils, such
as those found in Miami-Dade County. Pigeon peas are a
semi-perennial shrub in warmer areas. Many pigeon pea
and winged bean varieties are short day and only flower
during the fall. There are some day neutral varieties avail-
able of both crops. Fertilizer recommendations for pole
beans are generally applicable to this group. All of these
crops are started from seed, though winged beans require
scarification prior to planting. All the indeterminate types
need some type of support, ranging from individual bam-
boo stakes to trellises. For pest control products, these
crops are included in Crop Group 6 (Legume Vegetables
[Succulent or Dried]), with the exception of pea shoots
which are not in a crop group at present.


BOTANY


Nomenclature
Cluster bean, Guar Cyamopsis tetragonolobus

Edamame Glycine max

Fenugreek, methi Trigonella foenum-gracum

Hyacinth bean, lablab bean Lablab purpureus
(Dolichos lablab, D. nigar, Lablab vulgaris)

Pigeon pea Cajanus cajan

Snow / snap (edible podded) pea -Pisum sativum

Winged bean Psophocarpus tetragonolobus (Fig. 8-3)

Yard-long bean Vigna unguiculata



SOLANUMS

The Asian solanum group (Tables 4a and 4b) includes
three types of eggplant and bird's eye pepper. Pea egg-
plant, which was discussed in previous editions of the
Handbook, is on the Federal Noxious Weed list, so it has
not included here. The harvestable product includes fruits
which are eaten at the immature or mature stage. All can
be grown on raised beds with or without plastic mulch and


using either drip or subsurface irrigation. As with most
eggplants, these types tend to be short-lived perennials,
especially the Thai eggplant which is a relatively compact,
stocky plant. They can be severely pruned and allowed
to regrow if staking does not prohibit this operation.
Fertilizer recommendations for eggplant should be used for
the three types of eggplant, while those for peppers should
be followed for bird's eye peppers (Table 4c). These crops
can be started from seed or transplants. All the indetermi-
nate types need some type of support.



BOTANY

Nomenclature
Oriental eggplant, Japanese / Chinese Solanum melo-
gena

Thai eggplant Solanum melogena (Fig. 8-4)

Indian eggplant Solanum melogena

Bird's-eye pepper Capsicum frutescens though some
say perhaps C. chinense


SEED SOURCES


Evergreen Seeds, http://www.evergreenseeds.com/

Johnny's Selected Seed, http://www.johnnyseeds.com/

Kitazawa Seeds, http://www.kitazawaseed.com/

Known-you Seed Company, Ltd., http://www.knowny-


Oriental Enterprises,

Redwood City Seed Company, http://www.ecoseeds.
com/

Sakata, http://www.sakata.com/

Takii Seeds, http://www.takii.com/


Page 80







Page 81


Chapter 8: Production of Major Asian Vegetable Production in Florida


Table 3a. Names, Life Cycle, Varieties and Trellising Requirements of Asian Legumes


Crop
Cluster bean, Guar
Edamame
Fenugreek, methi
Hyacinth bean, lablab bean
Pigeon pea (a short-lived perennial)
Snow / snap (edible podded) pea
Winged bean
Yard-long bean


Life cycle
Annual
Annual
Annual
Annual
Short-lived perennial
Annual
Annual
Annual


Varieties


Green Legend, Lucky Lion


Asia Purple, Asia White


Mammoth Melting Sugar, Dou Miao
Youdou
Orient Extra Long, Stickless Wonder


Table 3b. Seeding, Planting and Maturity Information for Asian Legumes


Planting dates Cluster bean Fenugreek Edamame Hyacinth bean
North Florida Mar Apr; Mar Apr; Mar Apr; Mar Apr;
Aug Aug Aug Aug
Central Florida Feb Mar; Feb Mar; Feb Mar; Feb Mar;
Aug Sept Aug Sept Aug Sept Aug Sept
South Florida Sept Apr Sept Apr Sept Apr Sept Apr
Seeding information
Distance between rows (in) 24 9 20 24 20
Distance between plants (in) 6 2 3, thin to 4 (if only 2 6 4 6
growing a small amount)
Seeding depth (in) 1 1.5 1 1.5 1 1.5 1 1.5
Seed per acre 43,560 348,480 156,820 78,409
Days to maturity from seed 90- 120
Plant populations (acre)
Planting dates Pigeon pea Snow / snap pea Winged bean Yard-long bean
North Florida Jan Mar Mar July
Central Florida Nov Feb Feb Aug
South Florida Mar Apr Nov Feb Mar Apr Sept Apr
Seeding information
Distance between rows (in) 24 36 30 36 (hand harvest) 36 28 36
8- 10 (machine harvest)
Distance between plants (in) 24 36 1.2 2 8 2 -4
Seeding depth (in) 1 1.5 1 1.5 1 1.5 1 1.5
Seed per acre
Days to maturity from seed 180 (early varieties); 90 if day neutral varieties 70
270 365 days (late varieties) are used; SD otherwise
Plant populations (acre) 10,890 174,240 (hand) 21,7801 112,012


Trellising
Yes
No
No
No
No
Yes
Yes
Yes







Vegetable Production Handbook


Table 4a. Names, Varieties and Trellising Requirements of Asian Solanums


Crop Varieties Staking

Oriental eggplant, Japanese / Chinese Japanese: Hybrid Mangan Yes
Chinese: Hybrid Purple Charm, Ma-Zu Purple
White: Hybrid White Ball
Green: Green Beauty M
Thai eggplant this can be a short-lived perennial pe: Gr ViolMaybe
Purple: Hybrid Violet Prince
Variegated: Hybrid Tiger

Indian eggplant, dark & wine colored Hybrid Bharata Star, Hybrid Chu-Chu Yes

Bird's-eye pepper Maybe




Table 4b. Seeding, Planting and Maturity Information for Asian Solanums

Eggplant
Planting dates Japanese/ Chinese Thai Indian Bird's eye peper
North Florida Feb Mar Feb Mar Feb Mar Aug 15;
Feb Mar
Central Florida Aug Sept; Aug Sept; Aug Sept; Aug Sept;
Jan Feb Jan Feb Jan Feb Jan Mar
South Florida Aug Feb Aug Feb Aug Feb Aug Feb
Seeding information
Distance between rows (in) 36 72 36 72 36 72 36 -48
Distance between plants (in) 18 -40 36-60 18-40 10 -24
Seeding depth (in) 0.5-0.75 0.5-0.75 0.5-0.75 0.5-0.75
Seed per acre to transplant (Ibs) 0.25-0.5 0.25- 0.5 0.25 -0.5 0.25-0.5
Days to maturity from transplant
Plant populations (acre) 9,680 9,680 4,840 17,500


Page 82






UF UNIVERSITY of
UF FLORIDA
IFAS Extension
2010-2011


Cucurbit Production in Florida

S.M. Olson, E.H. Simonne, W.M. Stall, P.D. Roberts, S.E. Webb, and S.A. Smith


BOTANY
Nomenclature
Family Cucurbitaceae
Cucumber Cucumis sativus
Cantaloupe- Cucumis melo
Summer squash Cucurbita pepo
Pumpkin (jack-o-lantern is C. pepo; some processing
pumpkins are C. maxima and C. moschata)
Butternut squash Cucurbita moschata
Tropical pumpkin (Calabaza) Cucurbita moschata
Winter squash Cucurbita maxima e.g. hubbard,
buttercup, and Turk's Turban
Watermelon Citrullus lanatus

Origin
Cucurbits originated in several different locations:
cucumber (India); cantaloupe (Africa); summer squash
(Mexico, Central America); butternut squash (Mexico,
Central America); winter squash (South America); and
watermelon (Central Africa).

Related Species
Several Oriental and specialty vegetables, including
Chinese winter melon, calabash gourd, luffa gourd, bitter
melon, and chayote are also included in the Cucurbitaceae
family.



VARIETIES
Variety selection, often made several months before
planting, is one of the most important management deci-
sions made by the grower. Failure to select the most suit-
able variety or varieties may lead to loss of yield or market
acceptability.

The following characteristics should be considered in
selection of vine crop varieties for use in Florida:

Yield: The variety selected should produce crops equiv-
alent to the best varieties available. In recent years, the
average harvested yields per acre of vine crops in Florida
have been: fresh market cucumber 525 bu, processing
cucumbers 10 tons, cantaloupe -200 cwt, pumpkins -
experimental yields average about 200 cwt, summer squash
- 300 bu, Tropical pumpkin calabazaa) 500 cwt, and water-


melon 250 cwt. In most instances, however, harvested
yield is usually much less than potential yield because of
market constraints.

Disease Resistance: Varieties that combine disease resis-
tance with other desirable horticultural characteristics should
be selected when possible. Most modern cucumber varieties
are resistant or tolerant to angular leaf spot, anthracnose,
downy mildew, powdery mildew, cucumber mosaic virus,
and scab. Some cantaloupe varieties have tolerance to downy
and powdery mildew, and fruit should be resistant to fruit
rots. Unfortunately, disease tolerance is limited in squash
and pumpkin varieties at the present time. However, summer
squash varieties resistant to a number of diseases, includ-
ing viruses, are available to growers in limited numbers.
Watermelon varieties selected for use in Florida should have
resistance to anthracnose-race 1 and fusarium wilt. There
is considerable variation among varieties in the degree of
fusarium resistance; select varieties with high wilt resistance
that have qualities compatible with other requirements.

Horticultural Quality: Slicing cucumber fruit should
be smooth and uniformly dark green, have an appropri-
ate length:diameter ratio, have small seeds that are slow
to develop, and have a desirable flavor. Pickling cucum-
ber fruit should be firm, medium to dark green in color,
have a small seed cavity, an L/D ratio of about 3 at 11/4 in.
diameter, and good brining qualities if it is to be brined.
Gynoecious plants are preferred. Western-type cantaloupes
should be sutureless (smooth) or nearly so, round to slight-
ly oval, fully netted, and about 3 lb average weight with a
thick deep-salmon interior, and should have a small tight
seed cavity, high soluble solids (11% is required for the
U.S. Fancy grade), and a pleasant aroma and taste. Eastern-
type cantaloupes are sutured and have soft flesh. Desirable
traits in pumpkin varieties include a deep orange rind that
colors early, smooth fruit, a stem that is proportional to the
fruit size and adheres tightly to the fruit, and freedom from
fruit rots. Summer squash fruit should have color appropri-
ate to the market requirements, retain their gloss as they
mature, and be slow to develop seed. Winter squash fruit
should be attractively colored; have a smooth, hard rind;
deep orange flesh; be resistant to storage rot; and have an
appropriate storage life. Watermelon fruit size and shape;
rind color, thickness, and toughness; seed size, number,
and color; and flesh color, texture, and soluble solids (10%


Page 83


Chapter 9.






Vegetable Production Handbook


is required for designation as very good internal quality)
are all important characteristics to be considered in selec-
tion of watermelon varieties. Ability to germinate in cold
soils and general plant vigor may be important in certain
situations.

Adaptability: Vine crops are well adapted to produc-
tion in Florida for spring, early summer, and fall markets
and to the winter market in the very warmest growing
areas. Successful varieties must perform well under the
range of environmental conditions encountered in these
seasons and in various locations in Florida.

Market Acceptability: For all vine crops, growers must
be aware of the needs of the particular market they intend
to supply, and grow varieties that produce crops that satisfy
that market.


VINE CROP VARIETIES FOR FLORIDA
Cucumber (Fig. 9-1)
Pickling:
Calypso (H)1 (GY)2
Excel (H) (GY)
Eureka (H) (MO)
FMX 5020 (H)
Jackson Classic (H) (GY)
Napoleon Classic (H) (MO)
Royal (H) (GY)
Transamerica (H)
Slicing:
Cobra (H) (GY)
Dasher II (H) (GY)
Daytona (H) (GY)
General Lee (H) (GY)
Indy (H) (GY)
Lightning (H) (GY)
Panther (H) (GY)
Prancer (H) (GY)
Speedway (H) (GY)
Thunder(H) (GY)
'(H=hybrid)
2(Flower Habit GY=gynoecious,MO=monoecious)


Athena (H)
Eclipse (H)
Odyssey (H)
Vienna (H)
'(H=hybrid)


Miniature:< 1 lb
Jack-Be-Little
Jack-Be-Quick
Munchkin


Cantaloupe (Fig. 9-2)






Halloween Pumpkin


Halloween Pumpkin continued
Miniature:< 1 lb continued
Wee-Be-Little (PVP)'
Small: 1-5 lb
Baby Pam
Little Lantern
Pick-A-Pie (H)
Small Sugar
Trickster (H)2
Medium: 5-10 lb
Autumn Gold (H)
Jack of All Trades (H)
Magician (H)
Magic Lantern (H)
Merlin (H)
October (H)
Wizard (H)
Large: 10-20 lb
Big Autumn (H)
Connecticut Field
Gold Medal (H)
ProGold 510 (H)
Giant: 25-80 lb
Prizewinner (H)
'(PVP=Plant Variety Protection)
2(H=hybrid)


Squash
Summer (yellow):
Conqueror III (H) (SN)
Dixie (H)' (CN)2
Enterprise (H) (SN)2
Gentry (H) (CN)
Goldbar (H) (SN)
Lemondrop L (H) (SN)
Lioness (H) (SN)
Medalion (H) (CN)
Prelude (H) (CN)
Prelude II (H) (CN)
Sunbrite (H) (CN)
Sunglo (H) (CN)
Suwannee (H) (CN)
Summer (zucchini):
Cash Flow (H)
Dividend (H)
Envy (H)
Green Eclipse (H)
Payroll (H)
Senator (H)
Seneca Zucchini (H)
Spineless Beauty (H)
Springtime 843 (H)
Acorn (Fig. 27-3):
Mesa Queen (H)
Table Ace (H)
TayBelle PM (H)


Page 84







Chapter 9: Cucurbit Production in Florida


Squash continued
Butternut (Fig. 9-4):
Ultra (H)
Waltham
Zenith (H)
'(H=hybrid)
2(Type CN=crookneck, SN=straightneck)

Tropical Pumpkin (Calabaza)
Agriset 9001 vining type
La Estrella (H) compact plant

Watermelon
Diploid:
Celebration (H)'
Duration (H)
Fiesta (H)
Gold Strike (H) (orange flesh)
Jamboree (H)
Mardi Gras (H)
Regency (H)
Royal Star (H)
Royal Sweet (H)
Sangria (H)
Sentinel (H)
Summer Flavor 790 (H)
Summer Flavor 800 (H)
Summer Flavor 900 (H)
Triploid (Seedless, Large):
Freedom (H)
Genesis (H)
Gypsy (H)


Page 85


Watermelon continued
Triploid (Seedless, Large) continued:
Liberty (H)
Melody (H)
Millionaire (H)
Olympia (H)
Revolution (H)
Ruby Premium (H)
Sugar Coat (H)
SugarHeart (H)
Sugar Shack (H)
Sugar Time (H)
Super Crisp (H)
SummerSweet 5244 (H)
SummerSweet 5544 (H)
Super Seedless 7177 (H)
Sweet Delight (H)
Sweet Treasure (H)
Tri-X-212 (H)
Tri-X-313 (H)
Tri-X-Carousel (H)
Tri-X-Palomar (H)
Triton (H) (yellow flesh)
Triploid (Seedless, Mini):
Leopard (H)
Mohican (H)
Petite Treat (H)
Solitare (H)
Sugar Bite (H)
Summer Bite (H)
Valdoria (H)
Vanessa (H)
Wonder (H)
'(H=hybrid)


Table 1. Seeding and planting information for cucurbits.

Planting dates Cucumber Cantaloupe Pumpkin1 Squash2 Watermelon
North Florida Feb Apr; July Aug Feb 15 Apr 15 Early July Feb Apr; Aug Sept 15 Feb 15 -Apr 15
Central Florida Jan Mar; Sept Jan 15 Mar 15 Mid July Jan Apr; Aug Sept Jan 15 Mar 15
South Florida Sept Feb Dec 15 Mar 1 Early August Aug Mar Dec 15 Mar 1
Seeding information Bush Vining
Distance between rows3 (in) 48 -60 60 -72 60 108 36 -48 60 108 60 108
Distance between plants (in) 6 12 24 -36 36-60 12 24 36-60 24 72
Seeding depth (in) 0.5 0.75 0.5 1.0 1.5 2.0 1.0 1.5 1.5 2.0 1.5 2.0
Seed per acre (lb) 2-4 1 -2 4- 5 2- 3 1 1.5 1 -3
Days to maturity from seed 40-65 85- 110 80- 100 40-50 85- 120 80- 100
Days to maturity Not 70 90 70 90 Not Not 60 90
from transplant recommended recommended recommended
Plant populations4 (acre) 21,780 4,356 2,904 14,520 2,904 4,356
1 For Halloween market, for tropical pumpkin follow planting dates for squash.
For vining types in fall, plant during July same as pumpkins
3 Cucumber and squash can be grown in two rows per bed (especially mulch culture) with 12 to 18 inches between rows on the bed (Fig. 9-5).
4 Populations based on closest between and within row spacing.







Vegetable Production Handbook


SEEDING AND PLANTING

Planting dates and seeding information for cucurbits are
given in Table 1.



TRIPLOID WATERMELON PRODUCTION
Fruit of diploid watermelon varieties may contain as
many as 1,000 seeds in each fruit. The presence of seeds
throughout the flesh makes the removal of seeds while eat-
ing difficult. The seeds in slices or chunks of watermelon
sold in retail stores or salad bars are a nuisance. One rea-
son that seedless grapes are more popular with consumers
than seeded varieties is that the consumer does not have to
be concerned with and inconvenienced by the seeds while
the fruit is being eaten. With proper care, seedless water-
melons have a longer shelf life than seeded melons. This
may be due to the fact that flesh break down occurs in the
vicinity of seeds, which are absent, in seedless melons.

Hybrid triploid (seedless) watermelons have been grown
for over 40 years in the United States. However, it was not
until recently that improved varieties, aggressive market-
ing, and increased consumer demand created a rapidly
expanding market for triploid watermelons. The seed-
less condition is actually sterility resulting from a cross
between two plants of incompatible chromosome comple-
ments. The normal chromosome number in most living
organisms is referred to as 2N. Triploid watermelons are
produced on highly sterile triploid (3N) plants which result
from crossing a normal diploid (2N) plant with a tetraploid
(4N). The tetraploid is used as the female or seed parent
and the diploid is the male or pollen parent (Diagram 1).
Since the tetraploid seed parent produces only 5 to 10% as
many seeds as a normal diploid plant, seed cost is consid-
erably more than that of diploid, open-pollinated varieties
and higher than diploid watermelon varieties. Tetraploid
lines are usually developed by treating diploid plants with
a chemical called colchicine.

Tetraploid parental lines normally have a light, medium,
or dark green rind without stripes. By contrast, the diploid
pollen parent almost always has a fruit with a striped rind.
The resulting hybrid triploid melon will inherit a striped
pattern. Growers may occasionally find a non-striped fruit
in fields of striped triploid watermelons. These are the
result of accidental self pollinations of the tetraploid seed
parent during triploid seed production. Tetraploid fruit are
of high quality but will have seeds and must not be sold as
seedless. The amount of tetraploid contamination is depen-
dent upon methods and care employed in triploid seed
production.

Sterile triploid plants normally do not produce viable
seed. However, small, white rudimentary seeds or seed-
coats, which are eaten along with the fruit as in cucumber,


Female Parent (2N)

I
Colchicine



Male Parent (2N) X Female Parent (4N)



Triploid (3N) Seed

+ o- Pollenizer (2N)


Seedless Watermelons

Diagram 1. Steps involved in triploid watermelon seed pro-
duction. To produce seed, a diploid (2N) female
parent plant is treated with colchicine to produce
the solid-colored female tetraploid (4N) parent; this
is crossed with a striped male parent (2N) which
results in triploid (triploid) watermelon seed (3N).
To produce a crop of triploid watermelons, the 3N
seed is interplanted with a 2N pollenizer variety.


develop within the fruit. The number and size of these
rudimentary seeds vary with variety. An occasional dark,
hard, viable seed is found in triploid melons.

Triploid watermelons can be grown successfully in
areas where conventional seeded varieties are produced.
However, they require some very unique cultural practices
for successful production.

Stand Establishment
Containerized production of triploid watermelon
transplants is essential because of the special conditions
required for seed germination, emergence, and early
plant development not found in open-field situations.
Furthermore, the extra cost of seedling production is justi-
fied because triploid watermelon seeds costs are about
six times greater than those of diploid hybrid seeds and
60 times greater than open-pollinated diploid watermelon
seeds. One seed per cell should be planted 1 inch deep
with the radicle (pointed end) up to reduce seedcoat adher-
ence to the cotyledons. Transplants have been successfully
produced with peat pellets or in trays containing sterile
media with 1 to 2 inch cell size. The tray is watered lightly
to bring the seed and mix in contact. Stacked trays are
placed in a germination chamber 85-90'F for two days or
until radicles are visible in the cell drainage holes. The
trays are then arranged in a greenhouse with day tem-
perature 70-80'F and night temperature 65-70'F where
temperature control can be achieved. Plants are fertilized
every three days with a solution containing 50 ppm N from
Ca(N03)2 and KNO3 from cotyledon expansion until the
first true leaf is fully expanded, then with a 200 ppm N


Page 86







Chapter 9: Cucurbit Production in Florida


solution applied every other day until the second true leaf
is fully expanded, finally the fertilizer is reduced for sev-
eral days before transplanting to the field. Plants are ready
for transplanting when the roots are sufficiently developed
to permit removal from the cell with the entire growing
mix volume intact. This will require three to five weeks
depending on cell size and growing conditions.

Field Arrangement
There are two methods that can be used to incorporate
pollenizer plants into the field. Dedicated row pollenizer
plantings place the pollenizer variety in the outside row
and then every third row. An alternative is to plant the pol-
lenizer between every third and fourth plant in-row without
changing plant spacing. When this latter method is chosen,
the use of a special pollenizer is recommended. The use
of standard diploid varieties planted in-row may decrease
yields of closely associated triploid plants. Special pol-
lenizer varieties have been developed solely for pollen
production and most do not produce marketable fruit. The
use of special pollenizers planted in-row allows the field
to be 100% seedless. Special pollenizer varieties found to
perform well in Florida are listed below.


Triploid Watermelon Pollenizers


Jenny
Patron
Pinnacle
Polimax
Sidekick
SP-4


When using pollenizer plants arranged in dedicated
rows, it is important to use a pollenizer variety that is mar-
ketable because up to one-third of all melons produced in
the field will be of this variety.

When dedicated rows are used, special pollenizer plants
should be transplanted at the same times as triploid plants.

Cultural Practices
Plant spacing requirements vary depending on variety
selection, growing area, time of planting, and soil type. In
general, early growth of triploid plants is slower than that
of diploid plants. However, triploid plant size eventually
exceeds that of diploid plants. Seed development in fruit
of diploid varieties inhibits further flowering and fruit set.
This inhibition does not exist in triploids; therefore, plants
continue to produce fruit as long as viral infection does not
occur, insects and foliar diseases are controlled and envi-
ronmental conditions are favorable. Triploid plant popula-
tion density may be 10 to 20% less than that recommended
for production of diploid watermelon varieties. Triploid


watermelon production has been successful with 25-30 sq.
ft. per plant.

All methods of irrigation including overhead, drip, seep-
age, and furrow are used successfully in producing triploid
watermelons. Maintaining soil moisture at optimum levels
is critical for triploid watermelon production. Water stress
(drought) can increase the incidence of blossom-end rot
and result in poorly shaped, bottle-neck fruit. Excessive
field moisture has been associated with hollowheart, a dis-
order which seems to be more severe in some varieties of
triploid melons than in diploid varieties.



FERTILIZER AND LIME

For unmulched crops, incorporate all P205, micro-
nutrients, and 25 to 50% of N and K20 in the bed area.
Apply no more than 25% N and K20 broadcast for sub-
surface irrigated crops. This "modified broadcast" method
improves fertilizer efficiency. Apply remaining N and
K20 as a sidedressing when squash has four to six true
leaves or when vines begin to run.

For mulched crops under subsurface irrigation, broad-
cast all P205, micronutrients, and 20 to 25% of N and K20
in the bed area. Apply remaining N and K20 in bands in
grooves (2 to 3 inches deep) and 8 to 10 inches from row.
Use a single band in bed center for twin-row crops and two
shoulder bands for single-row crops.

For mulched crops with sprinkler irrigation, incor-
porate all fertilizer in bed before mulching. Cover with
unfertilized soil so fertilized soil is likely to remain moist.
Plastic mulch might need to be perforated to provide irri-
gation infiltration on deep, drought sands. Supplemental
N and K20 can be applied by liquid fertilizer injection
wheel.

For drip irrigated crops, broadcast all P205, micronutri-
ents, and up to 20 to 25% of N and K20 in the bed. Apply
remaining N and K20 through the irrigation tube.

Soil test and fertilizer recommendations for cucurbits on
mineral soils are given in Table 2. An injection schedule
for N and K for cucurbits grown on soils testing very low
in K is given in Table 3a and 3b.



PLANT TISSUE ANALYSIS

Plant tissue analysis information for cucurbits is given
in Table 4. The analysis was done at the early bloom stage,
using the most recently matured leaf.


Page 87







Vegetable Production Handbook


Table 2. Soil test and fertilizer recommendations for cucurbits on mineral soils.1


Bed
spacing (ft)


N Ib/A3 VL L M H VH


(lb/A/crop season)


150 120 100 80 0

150 150 120 100 0

150 120 100 80 0


VL L M H VH
K203


0 120 100 80 0 0

0 150 120 100 0 0

0 120 100 80 0 0


6.5 6 150 120 100 80 0 0 120 100 80 0 0
Watermelon
6.0 8 150 150 120 100 0 0 150 120 100 0 0
1 See Chapter 2 section on supplemental fertilizer application and best management practices, pg 11.
2 Summer and winter

3 Seeds and transplants may benefit from applications of a starter solution at a rate no greater than 10 to 15 lbs/acre for N and P205, and applied through the plant hole or near
the seeds.


Table 3a Injection schedule for N and K for cucurbit crops grown on soils testing very low in K.

Bed Total nutrients (lb/A) Crop development Injection (Ib/A/day)1
Crop spacing (ft) N K20 Stage Weeks2 N K20
Cucumber 6 150 120 1 1 1.0 1.0
2 2 2.0 1.5
3 6 2.5 2.0
4 1 2.0 1.5
Muskmelon 5 150 150 1 2 1.0 1.0
2 3 2.0 2.0
3 3 2.5 2.5
4 2 2.0 2.0
5 2 1.0 1.0
Squash 6 150 120 1 2 1.5 1.0
2 5 2.5 2.0
3 4 1.5 1.5
Watermelon 8 150 150 1 2 1.0 1.0
2 2 1.5 1.5
3 4 2.5 2.5
4 3 1.5 1.5
5 2 1.0 1.0
1 All nutrients injected. Actual amounts may be lower depending on amount of N and K20 placed in the bed and the K soil test result.
2 Starting from date of seedling emergence or transplanting. First two weeks worth of injecting can be omitted if 25% of total N and K20 was applied preplant.


Target pH



Cucumber
6.5
Muskmelon
6.5
Pumpkin
6.5
Squash2


Page 88







Chapter 9: Cucurbit Production in Florida


Page 89


Table 3b. Supplemental fertilization recommendations for cucurbit crops grown in Florida on sandy soils testing very low in
Mehlich-1 potassium (K20).

Recommended-Supplemental fertilizationz
Production Measured "low" plant
System Nutrient Leaching raint" nutrient content xw..V Extended harvest season x.
Plasticulture N n/a 1.5 to 2 Ibs/A/day for 7 daysY 1.5 to 2 Ibs/A/day y' v
K20 n/a 1.5 to 2 Ibs/A/day for 7 daysY 1.5 to 2 Ibs/A/day y' V
Bare ground N 30 Ibs/As 30 Ibs/A8 30 Ibs/A v
K20 20 Ibs/As 20 Ibs/As 20 Ilbs/A v
z 1 A= 7,260 linear bed feet per acre (6-ft bed spacing); for soils testing "very low" in Mehlich 1 potassium (K20)
y Fertilizer injections may be done daily or weekly. Inject fertilizer at the end of the irrigation event and allow enough time for proper
flushing afterwards.
x Plant nutritional status may be determined with tissue analysis or fresh petiole-sap testing, or any other calibrated method. The "low" diagnosis needs to be based on UF/IFAS
interpretative thresholds.
w Plant nutritional status must be diagnosed every week to repeat supplemental application.
v Plant nutritional status must be diagnosed after each harvest before repeating supplemental fertilizer application.
u Supplemental fertilizer applications are allowed when irrigation is scheduled following a recommended method (see Chapter 3 on
irrigation scheduling in Florida). Supplemental fertilization is to be applied in addition to base fertilization when appropriate.
Supplemental fertilization is not to be applied "in advance' with the preplant fertilizer.
t A leaching rain is defined as a rainfall amount of 3 inches in 3 days or 4 inches in 7 days.

s Supplemental amount for each leaching rain.


Table 4. Plant tissue analysis at early bloom stage for cucurbits. Dry weight basis.

N P K Ca Mg S Fe Mn Zn B Cu Mo

Status Percent Parts per million
Cucumber
Deficient <2.5 0.25 1.6 1.0 0.3 0.3 40 30 20 20 5 0.2
Adequate range 2.5 -5.0 0.25 -0.6 1.6 -3.0 1.0 -3.5 0.3 -0.6 0.3 -0.8 40-100 30-100 20-50 20-60 5-10 0.3 -1.0
High >5.0 0.6 3.0 3.5 0.6 0.8 100 100 50 60 20 2.0
Toxic (>) 900 950 150
Cantaloupe
Deficient <4.0 0.4 5.0 1.0 0.35 0.2 40 20 20 20 5 0.6
Adequate range 4.0-5.0 0.4 -0.7 5.0 -7.0 1.0 -2.0 0.35 -0.45 0.2 -0.8 40-100 20-100 20-60 20-80 5-10 0.6 -1.0
High >5.0 0.7 7.0 2.0 0.45 0.8 100 100 60 80 10 1.0
Toxic (>) 900 150
Pumpkin
Deficient <3.0 0.3 2.3 0.9 0.35 0.2 40 40 20 25 5 0.3
Adequate range 3.0-6.0 0.3-0.5 2.3 -4.0 0.9 -1.5 0.35 -0.60 0.2 -0.4 40-100 40-100 20-50 25-40 5-10 0.3 -0.5
High >6.0 0.5 4.0 1.5 0.6 0.4 100 100 50 40 10 0.5
Summer Squash
Deficient <3.0 0.25 2.0 1.0 0.3 0.2 40 40 20 25 5 0.3
Adequate range 3.0-5.0 0.25 -0.5 2.0 -3.0 1.0 -2.0 0.3 -0.5 0.2 -0.5 40-100 40-100 20-50 25-40 5-20 0.3 -0.5
High >5.0 0.5 3.0 2.0 0.5 0.5 100 100 50 40 20 0.5
Watermelon
Deficient <2.5 0.25 2.7 1.0 0.25 0.2 30 20 20 20 5 0.3
Adequate range 2.5 -3.5 0.25 -0.50 2.7 -3.5 1.0 -2.0 0.25 -0.50 0.2 -0.4 30-100 20-100 20-40 20-40 5-10 0.3 -0.5
High >3.5 0.5 3.5 2.0 0.5 0.4 100 100 40 40 10 0.5







Vegetable Production Handbook


PETIOLE SAP TESTING

Fresh sap can be pressed from leaf petioles and analyzed
for nitrogen and potassium concentrations. Results can
be used to make adjustments in the fertilization program.
Sufficiency ranges for sap testing for cucurbit crops are pre-
sented in Table 5.


IRRIGATION

Cucurbit water requirements are slightly lower than
those of other vegetable crops. Peak water requirements
during rapid growth and development may average 90%
of reference evapotranspiration levels (ETo), decreasing
to 70% of ETo during the final growth period (Tables 3
to 6, Chapter 3, Principles and Practices of Irrigation
Management for Vegetables). Many of these crops have
extensive root systems and can obtain available ground
moisture, thus reducing irrigation requirements. It is
important to note that excessive irrigation can reduce crop
yields by leaching crop nutrients or promoting disease.
However, plant stress from limited water availability will
also reduce fruit size and quality.


POLLINATION OF CUCURBITS

Cucurbit plants have separate male staminatee) and
female pistillatee) flowers (Fig. 9-6). Male flowers gener-
ally appear on the plants several days before female flow-
ers. The female flower is easily recognized by the presence
of a miniature fruit below the flower petals. Pollen from the


male flower must be transferred to the female flower for
pollination and subsequent fruit development to occur.

Therefore, it appears that a sufficiently high honey-
bee population is necessary to insure that each flower is
visited at least eight times. How does this translate into
hives per acre? Recommendations from various sources
range from two hives per acre to one hive per 5 acres (Fig.
9-7). Under most conditions, however, one strong hive
per 2 acres should result in sufficient bee activity to effect
needed pollination.

Cucurbit flowers open shortly after sunrise and remain
open until late afternoon or early evening. Accordingly,
each flower is open for only a few hours. The period of
maximum honeybee the most common and effective polli-
nator of cucurbits activity closely coincides with the peri-
od when the flower is open. Honeybee visitation begins an
hour or two after sunrise and continues until mid-afternoon.
If temperatures are very warm, bee activity may decline
about noon. Research on cantaloupe pollination conducted
in California showed that bee visitations increased until 10
a.m. and then declined until 3 p.m. when activity almost
ceased.

Research on watermelon showed that the number of bee
visitations was more important than the length of time that
each bee stayed on the flower. Well-shaped, fully expanded
fruit occurred following eight bee visitations to a female
flower (Fig. 9-8). Fruit set was significantly reduced when
only four or two bee visitations were made. Hives should be
spaced around the perimeter of large fields to provide distri-
bution of bees over the entire field. To maintain the health


Table 5. Sufficiency ranges for petiole sap testing for cucurbits.

Crop development stage Fresh petiole sap concentration (ppm)
N03-N K
Cucumber
First blossom 800-1000 NR1
Fruit three-inches long 600-800
First harvest 400-600
Cantaloupe
First blossom 1000-1200 3000-32001
Fruits two-inches long 800-1000 -
First harvest 700-800 -
Squash
First blossom 900-1000 NR1
First harvest 800-900
Watermelon
Vines 6" in length 1200-1500 4000-5000
Fruits 2" in length 1000-1200 4000-5000
Fruits one-half mature 800-1000 3500-4000
At first harvest 600-800 3000-3500
1 NR-No recommended ranges have been developed.


Page 90







Chapter 9: Cucurbit Production in Florida


and activity of the bee colonies, pesticide applications to
the crop should be made when bees are not present in the
field, usually at dusk or after dark.



WEED MANAGEMENT

Herbicides labeled for weed control in cucurbit crops
are listed in Table 6.


INSECT MANAGEMENT

Insecticides approved for use on cucurbit crops are out-
lined in Table 8.



PRODUCTION COSTS

Example breakeven production costs for cucurbits
grown in Florida are given in Tables 9, 10, 11, and 12.


DISEASE MANAGEMENT
Chemicals approved for disease management in cucur-
bits are listed in Table 7.



Table 6. Chemical weed controls: cucurbit crops muskmelonss, cucumbers, squash, watermelon)

Time of Rate (Ibs. Al./Acre)
Herbicide Labeled crops application to crop Mineral Muck


Cucurbit Vegetable group:
Cucumbers, Melons, Squash
(summer and winter), Pumpkins,
edible gourds, bitter melon


Preplant incorporated,
Preemergence


Remarks: Controls germinating grasses. Incorporate 1 to 2 inches. Note precautions of reapplying within 12 months and planting non-
registered crops within 18 months. Label states control of crabgrass, foxtail, goosegrass, fall panicum and sprangletop.


Bensulide +
Naptalam
(Prefar 4E + Alanap)


Cantaloupes, Muskmelons,
Cucumbers, Watermelons


Remarks: Combination (tank mix) will provide wider range of weed control than either material alone. Incorporate into the soil lightly (0.5
to 1.0 inch) with suitable equipment prior to planting or incorporate preemergent treatments with overhead irrigation. Follow all precau-
tions on both labels.


Cucurbit Crop Group
(All)


Preplant
Directed-hooded
Row-middles


Remarks: Aim may be applied as a preplant burndown treatment and/or as a post-directed hooded application to row middles for the
burndown of emerged broadleaf weeds. May be tank mixed with other registered herbicides. may be applied at up to 2 oz (0.031 Ib ai).
use a quality spary adjuvant such as crop oil concentrate (coc) or non-ionic surfactant at recommended rates.


Clethodim
(Select)


Cucurbits (cucumber, squash,
melons and all commodities in


Postemergence


0.1-0.125


(Arrow) crop group)
(Select Max)
Remarks: Use Select for the control of annual and perennial grasses. Use a crop-oil concentrate at 1% v/v in the finished spray volume. Do not
apply more than 8 fl. oz. product/A per application. Do not apply within 14 days of harvest. Rate for Select Max is 9-16 floz/A with the use of a
non-ionic surfactant.


Clomozone
(Command 3 ME)


Summer squash
Winter squash


Remarks: Labeled rate for summer squash if 0.25 Ib a.i. Bleaching has been seen under adverse conditions at this rate. Suggest use as
tank mix to increase efficacy. May be applied to winter squash and processing pumpkins. See label for varieties and cultivars where appli-
cation is prohibited. Do not use on Jack-0-Lantern type pumpkins. May be used on processing type varieties. Read disclaimer on the label
before use.


Bensulide
(Prefar 4E)


5.0-6.0


Preplant or
Preemergence


Carfentrazone
(Aim)


5.0
(Bensulide)
+ 3.0-4.0
(Naptalam)


0.031


0.031


Preemergence
Preemergence
Row Middles


0.15
0.25-0.75
0.75


Page 91







Vegetable Production Handbook


Table 6. Continued.

Time of Rate (Ibs. Al./Acre)
Herbicide Labeled crops application to crop Mineral Muck
DCPA Seeded Melons: Cantaloupe, Early postemergence 6-8
(Dacthal W-75) Honeydew, Watermelon;
Cucumber, Squash: Summer, Winter
Remarks: Apply only when plants have 4 to 5 true leaves, well established and growing conditions are favorable for good plant growth.
Does not control emerged weeds. If weeds have emerged, cultivate prior to application. Do not incorporate.
Ethalfluralin + Clomozone Cucumber, Melons, Watermelons, Preemergence and Post-directed 2-3 pts
(Strategy) Squash, Pumpkins
Remarks: Strategy is a premix of ethalfluralin and clomozone at 1.5 + 0.5 Ibs/gal. Apply 3 pts. product post-seeding to surface prior to
weed and crop emergence. Must be applied no later than 2 days after seeding. Soil incorporate with overhead irrigation at 1/2 inch, or with
a rain(s) at no less that 1/2 inch within 5 days. Excessive rains or irrigations may cause injury. For furrow irrigation where no rainfall is
received, a shallow cultivation may be used to activate the herbicides. Do not apply before transplanting. Do not apply under row covers,
hot caps or polyethylene mulches. May be applied as a post-directed spray to row middles after crop emergence or transplanting. Do not
apply over plants. The premix controls a large number of grasses and broadleaf weeds.
Flumioxazin Melon group, Directed 0.125
(Chateau) Muskemelon, watermelon Row Middles
Remarks: Chateau may be applied up to 4oz product/application to row middles of raised plastic-mulched beds that are at least 4
inches higher than the treated row middle and the mulched bed must be a minimum of a 24-inch bed width. Do not apply after crops are
transplanted/seeded. All applications must be made with a shielded or hooded equipment. For control of emerged weeds, a burn down
herbicide may be tank-mixed. Label is a Third-Party registration (TPR,lnc). Use without a signed authorization and waiver of liability is a
misuse of the product.
Glyphosate Cucurbits Chemical fallow 0.3-1.0
(Roundup, Durango) Preplant, pre mergence,
Touchdown, Glyphomax) Pre transplant
Remarks: Roundup, Glyphomax and Touchdown have several formulations. Check the label of each for specific labeling directions.
Halosulfuron Cucumber, Cantaloupe, Honeydew Preemergence 0.024
(Sandea) and Crenshaw melons. Postemergence
Remarks: Apply uniformly at 1/2 oz. product with ground equipment in a minimum of 15 gallons of water per acre. For postemergence
applications, apply after the crop has reached the 2 true leaf stage, but before flowering. Use a non ionic surfactant for postemergence
applications. May be used for row middle treatments at up to 1 oz. product. Controls actively growing nutsedge species best POST. Do
not apply within 30 days of harvest for cucumber and 57 days for the melon subgroup.
Halsulfuron Cucurbit vegetables including 0.024-0.048
(Sandea) watermelon, squash, pumpkins
Cucumbers, and melons Row middles
Remarks: May be applied between rows of direct seeded or transplanted crop for the control of nutsedges and listed broadleaf weeds.
Apply at 0.5 to 1 oz. product per acre treated. Add a non-ionic surfactant.
Halosulfuron Watermelon Preemergence 0.024 0.036
(Sandea) Pre transplant
Remarks: Sandea may be applied preemergence to seeded watermelon on bare ground culture or pre-seeding to mulch-cultured melons.
Pre transplant applications may be made also to bare ground or mulched production. Transplanting should be no sooner than 7 days after
application. Applications may be 1/2 to 34oz product per acre. Use lighter rates on sandy soils with low organic matter.
Halosulfuron Pumpkins Preemergence 0.024 0.036
(Sandea) Winter Squash Pre transplant
Post transplant
Remarks: Sandea may be applied after seeding but before soil cracking or pre transplant. Transplanting should not be made sooner than
7 days after application. May be applied post over-the-top when plants reach the 4-5 true leaf stage, but before first female flowers appear.
Applications may be 1/2 to 34oz product per acre.
Naptalam Cantaloupes, Muskmelons, Preemergence Preplant 3.0-4.0
(Alanap-L) Cucumbers, Watermelons (Irrigated Melons)
Remarks: Apply within 48 hours of seeding. Apply preemergence to weeds and incorporate with overhead irrigation. Label states control
of germinating annuals such as lambsquarter, ragweed, purslane, cocklebur, white mustard, shepherdspurse, redroot pigweed, hairy galin-
gosa and carpetweed.


Page 92







Chapter 9: Cucurbit Production in Florida


Table 6. Continued.


Labeled crops


Time of
application to croo


Rate (Ibs. AI./Acre)
Mineral Muck


Cantaloupes, Cucumbers,
Watermelons


Postemergence Posttransplant


Remarks: Apply 1 month after planting when vines are starting to run but before weeds have emerged or immediately after transplanting.
Do not use when plants are under stress due to weather conditions. Do not tank mix with crop oil or adjuvants. Phytotoxicity may occur.


Paraquat
(Gramoxone Inteon)
(Firestorm)


Watermelon, Squash, Pumpkin,
Cantaloupe, Muskmelon, Cucumber


Preplant or Preemergence


Remarks: Controls emerged weeds only. Apply prior, during or after planting, but before crop emerges. Use a non-ionic spreader.


Paraquat
(Gramoxone Inteon)


Melons


Postemergence directed spray


Remarks: Controls emerged weeds only. Apply 1.5 to 3.0 pts. per sprayed acre with ground equipment directing spray between the rows
and use shields to prevent spray contact with the crop plants. Add a non-ionic surfactant at 8 fl. oz. per 100 gals. of spray mix. Do not
apply more than 3 times per season. A Special Local Needs (24c) label for Florida.


Pelargonic Acid
(Scythe)


Cucurbits (melons; cucumber,
gourd, pumpkin, squash,
muskmelon and watermelon)


Preplant
Preemergence
Directed-Shielded


3-10% v/v 3-10% v/v


Remarks: Product is a contact, non-selective, foliar applied herbicide. There is no residual activity. May be tank mixed with soil residual
compounds. Consult the label for rates and other information.
S-Metolachlor Pumpkin Inter-row 0.95 1.26
(Dual Magnum) Inter-hill
Remarks: Apply before weeds emerge at 1.0 to 1.33 pint/A as an inter-row or inter hill application in pumpkin. Leave 1 foot of untreated area
over the row, or 6 inches to each side of the planted hill and/or emerged pumpkin foliage (inter-row or inter-hill means not directly over th
planted seed or young pumpkin plants). Do not apply closer than 30 days before harvest.


Sethoxydim (Poast)


Cucurbits: all


Postemergence


0.188-0.28


Remarks: Controls actively growing grass weeds. A total of 3 pts. product per acre may be applied in one season. Do not apply within 14
days of harvest. Apply in 5 to 20 gals. of water adding 2 pts. of crop oil concentrate per acre. Unsatisfactory results may occur if applied
to grasses under stress. Use 0.188 lb. ai. (1 pt.) on seedling grasses and up to 0.28 lb. ai. (1.5 pts.) on perennial grasses emerging from
rhizomes, etc. Consult label for grass species and growth stage for best control.


Terbacil (Sinbar)


Watermelonn


Preemergence
Pretansplant
Row Middles


0 1 02


Remarks: For watermelon only. Apply 2 to 4 oz product (0.1 0.2 Ib ai) to seeded or transplanted watermelon preemergence after plant-
ing to seeded and pretransplanting to transplanted watermelon. May be applied under much and to row middles. Controls many annual
broadleaf weeds.


Herbicide


Naptalam
(Alanap-L)


3.0-4.0


0.63 0.94


0.47-0.93


Page 93







Vegetable Production Handbook


Table 7. Cucurbit fungicides and other disease management products.

Chemical Fungicide Max Rate /Acre Min. Days Pertinent diseases
(active ingredient) Group1 Application Season to Harvest or pathogens Remarks2
Be sure to read a current product label before applying any chemical.


(copper compounds)
Many brands available:
Badge SC, Badge X2,
Basic Copper 53, Champ
DP Dry Prill, Champ
Formula 2 FL, Champ
WG, Champion WP, COC
DF, COC WP, Copper-
Count-N, Cuprofix Ultra
40 Disperss, Cuprofix
MZ Disperss, Kentan DF,
Kocide 2000, Kocide 3000,
Kocide DF, Nordox 75WG,
Nu-Cop 3L, Nu-Cop 50WP,
Nu-Cop 50DF,

(sulfur)
Many brands available:
Cosavet DF, Kumulus DF,
Micro Sulf, Microthiol
Disperss, Sulfur 90W,
Thiolux Jet, Wettable
Sulfur
(maneb)
Many brands available:
Maneb 75DF, Maneb
80WP, and Manex



(mancozeb)
Many brands available:
Dithane DF Rainshield,
Dithane F45 Rainshield,
Dithane M45, Manzate
Flowable 4F, Manzate
Pro-Stick, Penncozeb
4FL, Penncozeb 75DF,
Penncozeb 80WP
ManKocide 61.1DF (man-
cozeb + copper hydroxide)





(chlorothalonil)
Many brands available:
Bravo Ultrex, Bravo
Weather Stik, Bravo
ZN, Choloronil 720,
Chlorothalonil 720SC,
Echo 720, Echo 90DF,
Echo ZN, Equus DF, Equus
720 SST, Initiate 720


M1 SEE INDIVIDUAL
LABELS


M2 SEE INDIVIDUAL
LABELS


M3 SEE INDIVIDUAL
LABELS


M3 SEE INDIVIDUAL
LABELS


M3 / M1 2.5 Ib


128 Ib 5


M5 SEE INDIVIDUAL
LABELS


Bacterial diseases (See
individual label)


Powdery mildew






Alternaria leaf spot
Anthracnose
Cercospora leaf spot
Downy mildew
Gummy stem blight


Alternaria leaf spot
Anthracnose
Cercospora leaf spot,
Downy mildew
Gummy stem blight




Alternaria leaf spot
Anthracnose
Bacterial fruit blotch
Cercospora leaf spot
Downy mildew
Gummy stem blight
Alternaria leaf spot
Anthracnose
Cercospora leaf spot
Downy mildew
Gummy stem blight
Powdery mildew


See label


See individual label. Do
not use when temperatures
are greater than 90F or
on sulfur-sensitive various.
Labeled for all cucurbits.


Limit is 7 appl/crop. Do not
tank mix with copper fun-
gicides. Some cantaloupe
varieties may be sensitive to
EBCD products, check label
or Extension resources for
this information
See individual labels.
Labeled for all cucurbits.







Labeled on
cucumber,melons, and sum-
mer squash. Not all diseases
labeled for every crop. See
label.


Recommended maximum
rate is less for certain
diseases including downy
mildew. Follow label recom-
mendations on watermelon
after fruit set. Labeled for all
cucurbits.


Page 94







Chapter 9: Cucurbit Production in Florida


Table 7. Continued.


Chemical Fungicide Max Rate /Acre Min. Days Pertinent diseases
(active ingredient) Group1 Application Season to Harvest or pathogens Remarks2
Be sure to read a current product label before applying any chemical.


Topsin M 70WP Topsin
4.5FL
Topsin M WSB
Thiophanate methyl
85WDG
T-methyl E-Ag WSB
(thiophanate-methyl)
Folicur 3.6G
Monsoon 3.6G
Orius 3.6F
(tebuconazole)

Nova 40W
Rally 40WSP
Sonoma 40WSP
(myclobutanil)


Procure 50WS and 480SC 3
(triflumizole)


Ridomil Gold SL
Ultra Flourish
(mefenoxam)


Ridomil Gold MZ 68WP 4 / M3
(mefenoxam + mancozeb)


Ridomil Gold/Copper 64.8 4 / M1
W
(mefenoxam + copper
hydroxide)
Ridomil Gold Bravo 76.4W 4 / M5
(mefenoxam + chlorotha-
lonil)


Pristine 38WG
(boscalid + pyraclostrobin)


Switch 62.5WG
(cyprodinal & fludioxonil)


7/11


SEE INDIVIDUAL
LABELS


8 fl oz


Anthracnose
Powdery mildew
Gummy stem blight
Target spot


24 fl oz 7


1.5 Ib 0




40 oz 0


SEE INDIVIDUAL
LABELS


2.5 Ib



2 Ib



3 1b


10 Ib 5



81b 5



12 Ib 7


18.5 oz 74 oz 0


9 & 12 14 oz.


See label 1
and
remarks


Powdery mildew
Gummy stem blight



Powdery mildew




Powdery mildew


Damping off caused by
Pythium spp.


Downy mildew



Downy mildew



Downy mildew
Certain leaf spots
Gummy stem blight
Downy mildew
Powdery mildew
Gummy stem blight
Anthracnose
Alternaria leaf spot
Certain leaf spots
Alternaria leaf spot
Gummy stem blight
Powdery mildew


Follow resistance manage-
ment guidelines on label.
Labeled for all cucurbits.


Maximum rate is lower for
powdery mildew. Gummy
stem blight suppression only
for watermelon, squash,
pumpkin, and melons only
Note that a 30 day plant back
restriction exists. Follow
resistance management
guidelines on label. Labeled
for all cucurbits.
Follow resistance manage-
ment guidelines on label.
Labeled for all cucurbits.
Apply at seeding in a 7-12"
band on soil over seed fur-
row. Labeled for all cucur-
bits.
Limit is 4 appl./crop.
Labeled for cucumbers, can-
taloupe, melons, watermelon
and summer squash.
Limit is 4 appl/crop



Limit is 4 appl/crop. Rate
for downy mildew is lower.
Labeled for all cucurbits.
Limit is 4 appl/crop & alter-
nate chemistry. Labeled for
all cucurbits.


Do not apply more than 56
oz/A per plot of land per year.
Do not make more than two
consecutive applications
before switching to fungi-
cide with a different mode
of action. Labeled for all
cucurbits.


Page 95







Vegetable Production Handbook


Table 7. Continued.


Chemical Fungicide Max Rate / Acre Min. Days Pertinent diseases
(active ingredient) Group1 Application Season to Harvest or pathogens Remarks2
Be sure to read a current product label before applying any chemical.


Amistar 80DF
(azoxystrobin)


Cabrio 20EG
(pyraclostrobin)





Flint 50WP
(trifloxystrobin)



Heritage
(azoxystrobin)





Reason 500SC
(fenamidone)

Sovran
(kresoxim-methyl)

Quadris 2.08FL
(azoxystrobin)


Quadris Opti
(azoxystrobin & chloro-
thalonil)


Quintec
(quinoxyfen)


PH-D
(polyoxin D zinc salt)


1.88 lb 1


16 fl oz 64 fl oz 0


11 2 oz




11 8 oz


8 oz 0




3 1b 1


5.5 fl oz 22 oz 14


19.2 0


11 15.4 fl oz 2.88 qt 1


11 & M5 3.2 pt


13 6 fl oz


19 6.2 oz


See label 1


24 fl oz 3


31 oz 0


Downy mildew
Powdery mildew
Gummy stem blight
Anthracnose
Alternaria leaf spot
Certain leaf spots
Downy mildew
Powdery mildew
Gummy stem blight
Anthracnose
Alternaria leaf spot
Certain leaf spots
Powdery mildew
Downy mildew



Anthracnose
Belly rot
Downy mildew
Gummy stem blight
Leaf spots- various
Powdery mildew
Downy mildew
Alternaria leaf spot

Powdery mildew
Gummy stem blight

Anthracnose
Belly rot
Downy mildew
various leaf spots
Powdery mildew
Anthracnose
Belly rot
Downy mildew
various leaf spots
Powdery mildew
Powdery mildew


Powdery mildew
Gummy stem blight
Gray mold
various leaf spots


Limit is 4 appl/crop for all
Qol fungicides. Do not make
more than two consecutive
applications. Labeled for all
cucurbits.


4 appl maximum. Same
as Amistar. Maximum rate
is less for downy mildew.
Labeled for all cucurbits.



Limit is 4 appl/crop & alter-
nate chemistry. Maximum
rate is higher for downy mil-
dew suppression. Labeled for
all cucurbits.
Do not make more than two
consecutive applications. Do
not make more than 6 appl/
crop. Labeled for all cucur-
bits.


Limit is 4 appl/crop & alter-
nate chemistry. Labeled for
all cucurbits.
Follow resistance manage-
ment guidelines on label.
Labeled for all cucurbits.
Limit is 4 appl/crop & alter-
nate chemistry. Labeled for
all cucurbits.



Limit is 4 appl/crop for all
Qol fungicides. Do not make
more than two consecutive
applications. Labeled for all
cucurbits.

Do no make more than 4
appl. Do not make more
than two consecutive appls .
Not labeled on all cucurbits;
labeled on various melons,
cantaloupe, and watermelon.
Use in alteration with fun-
gicides that have different
modes of action. Labeled for
all cucurbits.


Page 96







Chapter 9: Cucurbit Production in Florida


Table 7. Continued.

Chemical Fungicide Max Rate /Acre Min. Days Pertinent diseases
(active ingredient) Group1 Application Season to Harvest or pathogens Remarks2
Be sure to read a current product label before applying any chemical.


Ranman
(cyazofamid)


Gavel 75DF
(zoxamide + mancozeb)


Curzate 60DF
(cymoxanil)


Tanos 50DF
(cymoxanil & famoxa-
done)


Previcur Flex
Promess
(propamocarb hydrochlo-
ride)

Aliette 80WDG
Legion 80WDG
Linebacter WDG
(fosetyl-AI)
Alude
Fosphite
Fungi-phite
Prophyte
Topaz
(potassium phosphite)


Acrobat 50WP
(dimethomorph)


Forum
(dimethomorph)


Revus
(mandipropamid)

Presidio
(fluopicolide)


Serenade ASO
(Bacillus subtilis strain
QST 713)


21 2.75 fI oz 16.5 fl oz 0


22 / M3 2 Ib


27 3.2 oz



27&11 8oz




28 1.2 pt


33 5 Ib


16 Ib 5


See
Remarks


See
label and
remarks


6 pt 2


35 Ib 12 hr


SEE INDIVIDUAL
LABELS


40 6.4 oz


40 6 oz


40 8 fl oz


43 4 fl oz


32 oz 0


30 oz When spray
is dried


32 fl oz 0


12 fl oz 2


44 6 Ib


Downy mildew
Phytophthora blight


Alternaria leaf spot
Cercosopora leaf spot
Downy mildew


Downy Mildew


Downy mildew
Anthracnose



Downy Mildew
Pythium


Downy mildew
Phytophthora root and
fruit rot

Phytophthora, Pythium,
Fusarium, Rhizoctonia,
Downy Mildew


Downy mildew
Phytophthora blight


Downy Mildew


Downy mildew


Downy mildew
Phytophthora blight


Powdery mildew, Gummy
stem blight Downy mil-
dew


Limit is 6 appl/crop.Follow
resistance management
guidelines on label. Labeled
for all cucurbits.
Limit is 8 appl/crop. Some
cantaloupe varieties are sen-
sitive, check label. Labeled
for all cucurbits.
Use only with a labeled rate
of protectant fungicide. No
more than 9 appl/12 months.
Labeled for all cucurbits.
Limit is 4 appl/crop. Must
tankmix with a contact
fungicide. Limit is 72 oz/A
maximum/year. Labeled for
all cucurbits.
Use a tank mix partner.
See label for directions
using a contact fungicide
and Pythium suppression.
Labeled for all cucurbits.
Limit is 7 appl/crop. Do
not tank mix with copper
fungicides. Labeled for all
cucurbits.

Check label for required mini-
mum gall/acre, restrictions
for use following copper
appl., plant and environmen-
tal conditions that restrict
use, and for compatibility
with other materials
Limit is 5 appl/crop. Tank
mix with another fungicide.
Harvest after spray is dry.
Labeled for all cucurbits.
Limit is 5 appl/ crop. Apply
with another fungicide that
has a different mode of
action. Minimum gallons per
acre required. Labeled for all
cucurbits.
An adjuvant is recommended
for best control. Limit is 4
appl./crop
Tankmix with another fungi-
cide product with a different
mode of action. Labeled for
all cucurbits.
Do not use product alone.
Apply with registered fungi-
cide. OMRI listed.


Page 97







Vegetable Production Handbook


Table 7. Continued.

Chemical Fungicide Max Rate / Acre Min. Days Pertinent diseases
(active ingredient) Group1 Application Season to Harvest or pathogens Remarks2
Be sure to read a current product label before applying any chemical.
Serenade Max 44 3 Ib 0 Powdery mildew Do not use product alone.
(Bacillus subtilis strain Gummy stem blight, Apply with registered fungi-
QST 713) Downy mildew cide. OMRI listed.
Rhapsody 44 6 qt/100 gal 0 Powdery mildew Do not use product alone.
(Bacillus subtilis strain Gummy stem blight Apply with registered fungi-
QST 713) Bacterial fruit blotch cide. Labeled for all cucur-
Downy mildew bits. OMRI listed.
Certain leaf spots
Actigard 50WG (acibenzo- P 1 oz/A 4 oz 0 Downy mildew Suppression of disease.
lar-S-methyl) Powdery Mildew Labeled for all cucurbits.
Scab
Bacterial fruit blotch
Angular leaf spot
Regalia SC P 1% v/v dilu- 0 Powdery mildew For use in Organic produc-
(extract of Reynoutria tion Downy mildew tion
sachalinensis) Gummy stem blight
Actinovate AG NC See label for See label for disease Use an integrated pest man-
(Streptomyces lydicus) use suppression agement strategy. Product is
OMRI listed.
JMS Stylet Oil NC 3 qt 4 hr Aphid-transmitted virus- See label for specific appl.
es, powdery mildew Tech. (e.g. use of 400 psi)
Oxidate NC Various dilu- See label 0 Downy mildew See label for specific instruc-
(hydrogen dioxide) tion rates Powdery mildew tions for use with cucurbits.
Gummy stem blight
Anthracnose
Sonata NC 4 Ib 0 Powdery mildew Do not use product alone.
(Bacillus pumilus strain Downy mildew Apply with registered fungi-
QST 2808) cide. OMRI listed.
1 FRAC code (fungicide group): Numbers (1-44) and letters (M, NC, U, P) are used to distinguish the fungicide mode of action groups.
All fungicides within the same group (with same number or letter) indicate same active ingredient or similar mode of action. This infor-
mation must be considered for the fungicide resistance management decisions. M = Multi site inhibitors, fungicide resistance risk is
low; NC = not classified, includes mineral oils, organic oils, potassium bicarbonate, and other materials of biological origin; U = Recent
molecules with unknown mode of action; P = host plant defense inducers. Source: FRAC Code List 2009; http://www.frac.info/ (FRAC =
Fungicide Resistance Action Committee).
2 Information provided in this table applies only to Florida. Be sure to read a current product label before applying any chemical. The use
of brand names and any mention or listing of commercial products or services in the publication does not imply endorsement by the
University of Florida Cooperative Extension Service nor discrimination against similar products or services not mentioned.


Page 98







Chapter 9: Cucurbit Production in Florida


Table 8. Selected insecticides approved for use on insects attacking cucurbit crops.

Trade Name Rate REI Days to MOA
(Common Name) (product/acre) (hours) Harvest Insects Code1 Notes


Acramite-50WS
(bifenazate)
Actara
(thiamethoxan)

Admire Pro
(imidacloprid)
(see appropriate
labels for other
brands)
Admire Pro
(imidacloprid)

Agree WG
(Bacillus thuringi-
ensis subspecies
aizawai)


*Ambush 25W
(permethrin)




*Asana XL (0.66
EC)
(esfenvalerate)


Assail 30SG,
70WP
(acetamiprid)

Avaunt
(indoxacarb)
Aza-Direct
azadirachtinn)


Azatin XL
azadirachtinn)

*Baythroid XL
(beta-cyfluthrin)


0.75-1.0 lb

1.5-5.5 oz


7-10.5 oz


0.44 fl oz/10,000 12
plants


0.5-2.0 Ib


12 3 twospotted spider mite

12 0 aphids, flea beetles, whiteflies,
suppression of cucumber beetles
and leafminers at higher rates
12 21 (soil) aphids, cucumber beetles, leaf-
hoppers, foliage-feeding thrips,
whiteflies


21 aphids, whiteflies


4 0 lepidopteran larvae (caterpillar
pests)


12 7 leafminers, spider mites


6.4-12.8 oz 12 0 cabbage looper, cucumber
beetles, cutworms, leafminers,
Lygus bug, melonworm, pickle-
worm, plant bugs, rindworms,
squash bugs, squash vine borer,
stink bugs


5.8-9.6 fl oz


2.5-5.3 oz
1.1-2.3 oz


2.5-6.0 oz


1-2 pts, up to 3.5 4
pts, if needed


5-21 fl oz


12 3 cabbage looper, corn earworm,
cucumber beetles (adults), cut-
worms (seedling spray), grass-
hoppers, leafhoppers, Lygus bug,
rindworms, squash bug, squash
vine borer, stink bugs
12 0 aphids, cucumber beetles, leaf-
hoppers, melonworm, pickle-
worm, squash bug, squash vine
borer, whitefly
12 3 melonworm, pickleworm


0 aphids, beetles, caterpillars, leaf-
hoppers, leafminers, mites, stink
bugs, thrips, weevils, whiteflies


4 0 aphids, beetles, caterpillars,
leafhoppers, leafminers, thrips,
weevils, whiteflies


0.8-2.8 fl oz 12 0 Armyworm (1st and 2nd instars),
cabbage looper, corn earworm,
cucumber beetles, cutworms,
grasshoppers, melonworm, pick-
leworm, rindworms, stink bugs,
tobacco budworm


un One application per season.

4A Apply before pests reach dam-
aging levels.

4A Will not control thrips in flow-
ers. Do not use with other
Group 4A insecticides


4A Planthouse: One application to
transplants. See label for use on
mature greenhouse cucumbers.
11 Apply when larvae are small for
best control. OMRI-listed2.


6 Minimum of 7 days between
applications. No more than 2
sequential applications.
3 Do not apply more than 1.6 Ib
ai/acre per season.


Do not apply more than 0.25 Ib
ai/acre per season, (or 5 appli-
cations at high rate).


4A No more than 5 applications per
season. Do not use if another
group 4A insecticide has been
used.
22 Do not apply more than 24 oz/
acre per crop.
un Antifeedant, repellant, insect
growth regulator. OMRI-listed2.


un Antifeedant, repellant, insect
growth regulator.


Maximum amount per season:
11.2 fl oz/acre.


*Agri-Mek 0.15 EC 8-16 fl oz
(abamectin)


Page 99




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