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Organic cotton has provided significant price

premiums for growers willing to meet the many

challenges inherent in its production without the

aid of conventional pesticides and commercial

fertilizers. Growing organic cotton is demanding,

but with commitment, experience, and determination,

it can be done. This publication

covers the major steps in organic production of

cotton. It covers soil fertility, weed control options,

and alternative pest controls for the many

insect problems that plague cotton. Finally, marketing

of organic cotton is discussed as well.

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Organic cotton acreage declined 18% from 2000

to 2001 in the seven states where most of it is

came from one large organic cotton farmer in

New Mexico who lost it all to drought and withdrew

from organic cotton farming altogether. A

total of 11,459 acres of either certified organic or

transitional organic cotton was produced in 2001.

Texas produced the most organic cotton.8,338

acres.with Arizona and California being the

next two highest producing states.

World production of organic cotton amounts to

6,000 tons of fiber annually, or about 0.03% of

global cotton production. Turkey produces the

most at 29%, with the U.S. being second at 27%

organic cotton is highest in Europe (about 3,500

tons or 58% of the total) and the U.S. (about 2,000

increased at an annual rate of 22% between 1996

and 2000 (Organic Trade Association, 2001; cited

Growing cotton organically entails using cultural

practices, natural fertilizers, and biological controls

rather than synthetic fertilizers and pesticides.

A systems approach to organic production

involves the integration of many practices

(cover crops, strip cropping, grazing, crop rotation,

etc.) into a larger system. Through good

soil and biodiversity management, farms can

become increasingly self-sufficient in fertility,

while pest problems are diminished, and some

pests are even controlled outright. A diverse

rotation, using legumes and other cover crops,

is at the heart of good humus and biodiversity

management in an organic cropping system.

Cotton, for example, would be but one of several

crops an organic farmer would grow. For

more complete coverage of general organic crop

production, we recommend the ATTRA publication

In order to market a crop as .organic,. a grower

must be certified through a third party. This

process involves several on-farm inspections and

paying a certification fee. More on this subject

Applicants for certification are encouraged

to become familiar with provisions of the Final

Rule posted on the USDA.s National Organic

Organic production begins with organically

grown seed. If certified organic seed cannot be

located, untreated seed may be used as long as it

is not derived from genetically modified plants.

Most certifiers will accept proof that growers

have tried unsuccessfully to buy organic material

from at least three different suppliers as evidence

of unavailability. Federal organic regulations

also address composting and the use of raw

manures. These may have implications for cotton

production when used as fertilizer.

Mineral nutrition of crops in organic systems

comes from proper management of soil organisms

that are responsible for releasing nutrients.

Rather than feeding plants with fertilizer, organic

farmers feed the soil and let the soil organisms

feed the plants. The biological activity in the soil

can be likened to a digestive process whereby

organic food sources are applied to the soil and

then digested by soil organisms to release nutrients

for the crop. Soil mineral levels are built up

through the application of animal manure, compost,

soluble rock powders, and deep-rooted

cover crops that bring up nutrients from deep

within the soil. Plant nutrition is supplemented

with foliar fertilization in some situations. Soil

fertility, levels of organic matter, minerals, pH,

and other measurements can be monitored with

regular soil tests. The overall cropping sequence

fosters a system in which a previous crop provides

fertility benefits to a subsequent crop.such

as a legume cover crop providing nitrogen to a

following corn crop. Much more detailed soilfertility

information is available from ATTRA in

Throughout this publication, we use examples

from conventional farming that illustrate

principles relevant to organic cotton

production.

Crop rotation is a traditional agricultural practice

involving the sequencing of different crops

on farm fields; it is considered fundamental to

successful organic farming. Rotations are a

planned approach to diversifying the whole farm

system both economically and biologically,

bringing diversity to each field over time.

Rotations can benefit the farm in several ways.

Planned rotations are one of the most effective

means of breaking many insect pest and plant

disease cycles in the soil. Likewise, many problem

weeds are suppressed by the nature and timing

of different cultural practices. Rotations also

affect the fertility of the soil in significant ways.

The inclusion of forage legumes, in particular,

may serve as the primary source of nitrogen for

subsequent crops.

Rotation is an important means of controlling a

number of cotton pests, including nematodes.

Even basic corn-cotton rotations have been found

effective in reducing some species of nematodes

to non-host species is the standard recommendation.

A long-term cotton study at Auburn, Alabama,

showed that using winter annual legumes produced

cotton yields equivalent to those grown

using fertilizer nitrogen. The study found an 11%

yield increase for a 2-year cotton-legume-corn

rotation compared to continuous cotton grown

with legumes each year. Adding conventional

nitrogen fertilizer boosted the two-year rotation

cotton lint yields in this study another 79 pounds

per acre. A three-year rotation of cotton-vetch,

corn-rye (fertilized with 60 pounds of conventional

N/acre), followed by soybeans, produced

about the same cotton yields as the two-year rotation

Cover crops are crops grown to provide soil cover

and erosion protection. At the same time, cover

cropping may accomplish a number of other objectives,

including providing nitrogen to the subsequent

cotton crop when tilled into the soil,

improving tilth by adding organic matter, and

serving as a catch crop when planted to reduce

nutrient leaching following a main crop.

Fast, dense-growing cover crops are sometimes

used to suppress problem weeds as a .smother

crop. or allelopathic cover. The mere presence

of most cover crops reduces the competition from

weeds. Sometimes crops are no-till planted into

such covers. If the cover crop is not killed, it is

referred to as a .living mulch.. Some cover crops

that have been used successfully for weed suppression

include small grains (particularly grain

rye), several brassica species, hairy vetch, and

forage sorghums.

For the humid Cotton Belt, crimson clover, field

peas, and hairy vetch are excellent winter cover

crops for nitrogen production. Also, a mixture

of hairy vetch and rye works well for overall biomass

production. When flowering, these provide

nectar and pollen as alternate food for

beneficials. Hairy vetch is noted for its dense

spring cover and weed suppression. Cereal rye

provides an enormous amount of biomass to the

soil and is known to attract and shelter beneficial

insects. It also suppresses germination of

small-seeded weeds when left as a mulch cover

on the soil surface. Natural allelopathic chemicals

leach from the rye residue and inhibit weed

Weed suppression effectively ends once the rye

residue is incorporated. Weed suppression has

made rye attractive as a cover crop/mulch in notill

and ridgetill systems. Mowing or a burndown

herbicide is often used in conventional

systems to kill the rye cover crop so that no-till

plantings of field crops can be established. An

effective organic no-till system for cotton has yet

to be developed, but early indications are that it

will be. For more information on the potential

for organic no-till see the ATTRA publication

area. It is important to mow rye at the flowering

stage when the anthers are extended, and pollen

falls from the seed heads when shaken. If mowing

is done earlier, the rye simply grows back.

As allelopathic weed suppression subsides, a notill

cultivator may be used for weed control. This

is not a proven system for organic cotton production

but only presented here as food for

thought about the development of future organic

no-till systems.

In addition to producing nitrogen, cover crops

often provide excellent habitat for predatory and

parasitic insects and spiders. Some good insectary

plants often used as cover crops include alfalfa,

buckwheat, sweet clover, vetch, red clover,

white clover, mustards, and cowpeas. Migration

of beneficials from the cover crop to the main

crop is sometimes associated with the post-bloom

period of the cover crop. In these instances,

mowing the cover crops in alternate strips may

facilitate their movement, while the remaining

strips continue to provide refuge for other beneficial

species. Sickle-bar mowers are less disruptive

to beneficials than flail mowers, rotary

mowers, and mower conditioners with crimpers.

Long-term cotton cover-crop studies have also

study spanned 17 years, from 1973 to 1988. Cotton

grown after winter cover crops of rye + hairy

vetch produced an average of 234 pounds more

seed cotton per acre than a control treatment of

winter fallow. Cotton following pure vetch

showed a 129-pound increase, while yields after

rye + crimson clover had a 72-pound yield improvement.

In the long-term Louisiana study, cotton yields

declined for the first nine years when cover crops

were used, but increased steadily thereafter. In

the final four years of the study, cotton yields

were 360 pounds-per-acre higher following

vetch, compared to fallow + 60 pounds of fertilizer

N per acre. Averaged over the 30-year study

period, the highest cotton yields followed wheat

+ 60 pounds of fertilizer N, hairy vetch alone,

common vetch alone, or vetch + 40 pounds of N.

For additional information on cover crops, see

Cotton germinates at a soil temperature of 61° F

at a depth of about 2 in. With planting delayed

until the soil temperature reaches 66°, the crop

emerges rapidly and uniformly and is more vigorous

edge on weeds. The delay in operations

also allows additional growth of winter cover

crops where used. The downside of this strategy

may include risks of increased damage from

certain insect pests such as boll weevil, tobacco

budworm, and cotton bollworm.

Tillage and cultivation are the traditional means

of weed management for organic crops. Some

specific tillage guidelines and techniques for

weed management include the following:

. Preplant tillage. Where weeds such as

johnsongrass are a problem, spring-tooth harrows

and similar tools can be effective in

catching and pulling the rhizomes to the soil

surface, where they desiccate and die.

Disking, by contrast, trends to cut and distribute

rhizomes and may make the stand

even denser.

. Blind tillage. Blind cultivation employs finger

weeders, tine harrows, or rotary hoes

during the pre-emergent and early postemergent

phase. These implements are run

at relatively high speeds (6 mph plus) across

the entire field, including directly over, but

in the same direction as, the rows. The largeseeded

crops like corn, soybeans or sunflower

survive with minimal damage, while smallseeded

weeds are easily uprooted and killed.

Post-emergent blind tillage should be done

in the hottest part of the day when crop plants

are less turgid, to avoid excessive damage.

Rotary hoes, not harrows, should be used if

the soil is crusted or too trashy. Seeding rates

should be increased 5-10% to compensate for

. Inter-row cultivation. When annual weeds

are the concern, cultivation is best kept as

shallow as possible to bring as few weed

seeds as possible near the soil surface. Where

perennial, rhizomaceous weeds are a problem,

the shovels set furthest from the crop

row may be set deeper on the first cultivation

to bring rhizomes to the surface. Tines

are more effective than sweeps or duck feet

for extracting rhizomes. Later cultivations

should have all shovels set shallow to avoid

excessive pruning of crop roots. Earliest cultivations

should avoid throwing soil toward

the crop row. This places new weed seed into

the crop row where it may germinate before

the crop canopy can shade it out. As the crop

canopy develops, soil should be thrown into

the crop row to cover emerging weeds.

Inter-row cultivation is best timed to catch weeds

as they are germinating.as soon as possible after

rain or irrigation, once the soil has dried

enough to avoid compaction or surface crusting.

Prior to the 1950s, before modern herbicides became

available, flame weeders were used in the

U.S. to control weeds in cotton, sugar cane, grain

sorghum, corn, and orchards. Interest in flame

weeding has resurfaced in recent years with rising

herbicide costs. Weeds are most susceptible

to flame heat when they are young seedlings 1.2

inches tall or in the 3.5 leaf stage. Risk of damaging

the cotton plants diminishes as the cotton

grows and forms a bark on the stem. Broadleaf

weeds are more susceptible to flaming than

grasses. Grass seedlings develop a protective

sheath around the growing tip when they are

flamings may be necessary on grassy

weeds for effective control. Searing the plant is

much more successful than charring. Excessive

burning of the weeds often stimulates the roots

and encourages regrowth, in addition to using

more fuel.

Preplant flaming has commonly been referred to

as the stale seedbed technique. Prepared seedbeds

are flamed after the first flush of weeds has

sprouted. Cotton planting follows the flaming

without any further disturbance to the seedbed.

Assuming adequate moisture and soil temperature,

germination should occur within two

weeks. Note that a fine-to-slightly-compacted

seedbed will germinate a much larger number

of weeds.

Costs associated with flame weeding can vary.

Flamers have been built for $1,200 for an eightrow

kits cost around $1900 for an eight-row from

These kits do not include hoses, a tank, or a tool

bar. It is more cost-effective to pick these items

up locally from a gas dealer or salvage operation.

An Arkansas cotton grower uses a .water

shield. to help protect the cotton plants, but still

feels flaming should be delayed until the crop

has developed a woody bark on the stem (Vestal,

1992). Adapting flame technology requires

careful implementation. Thermal Weed Control

Systems (TWCS), Inc. of Neillsville, Wisconsin,

and Flame Engineering, Inc. (FEI), of Lacrosse,

Kansas, are two flame-weeding companies that

can provide technical assistance and equipment

ground speed but generally runs from 8-10 gallons

per acre, according to sources at Thermal

Weed Control. For an overview of weed management

strategies and options for agronomic

crops, please request the ATTRA publication

Biological and cultural insect control involves

understanding the ecology of the surrounding

agricultural systems and the cotton field and

making adjustments to production methods that

complement the natural system to our benefit.

To realize the full benefits of a biological approach

we need to move beyond asking how to

kill bugs and ask the larger question: Why do

we have bugs in our cotton fields in the first

place?

In a nutshell, we invite pest problems by planting

large expanses of a single susceptible crop.

When cotton is the only food available, bugs are

going to eat cotton. When we have a more diverse

farmscape involving many types of plants

and animals, the likelihood of severe pest outbreaks

diminishes. For more information on

farmscaping, request the ATTRA publication

Many types of insects feed on cotton plants and

threaten yields. Proper identification of these

pests as well as their natural enemies is the first

step in successful management of pests. State

Extension services typically have Internet based

information that can help with pest and beneficial

insect identification. Once the pest is properly

identified, a scouting program with regular

monitoring can help determine the pest pressures

and the densities of beneficial insects. When pest

pressures reach the economically-damaging

threshold, control actions become necessary. If

biological controls are to be used, they must be

started before the pests reach critical levels. That

is why monitoring is so important.

The use of beneficial insect habitats along crop

field borders has shown to increase the presence

of beneficial insects. These habitats provide shelter,

pollen and nectar sources, and refuge if the

fields are treated with a pesticide. In the event

you are releasing purchased beneficial insects,

these field-edge habitats will encourage the

beneficials to remain and continue their lifecycle

in that location, helping reduce the pest population.

Some pests may also inhabit the field-edge

habitats; therefore, these habitats should be monitored

along with the crop field. For additional

Though not completely organic, the Sustainable

Cotton Project.s BASIC program (Biological Agriculture

Systems in Cotton) offers California

growers strategies designed to save money and

reduce the need for pesticides, chemical fertilizers,

and water. The BASIC program utilized the

following strategies in their 2002 program that

showed a 73% reduction in pesticide use over

habitat plantings, and insect releases provided

to them. .Basic growers. had implemented

the principles on their own fields but

without the direct involvement of the basic program

staff. Regular IPM, intensive monitoring,

beneficials, and beneficial habitat can reduce

pesticide use whether you are organic or conventional.

For pesticide use questions or analysis

questions, contact Max Stevenson at:

maxstevenson@yahoo.com

Fields enrolled in the program were monitored

weekly. Monitoring included an overall

picture of the field and the local conditions,

the levels of pests and beneficials,

farmscape observations, the status of the adjacent

beneficial habitat, and any unusual

sightings or areas for concern. Farmers were

2532 fields

255,373 acres

103 fields

8,151 acres

11 fields

625 acres

given a copy of the monitoring form, and the

overall results were published bi-weekly in

a newsletter.

One of the .best management practices. promoted

by the BASIC program has been the

strip cutting of alfalfa. This practice

prevents the immigration of certain species

at harvest time and keeps one of the main

of the alfalfa (its preferred host) into the adjacent

cotton. BASIC field staff and mentor

growers were also able to provide technical

support for growers wanting to implement a

system of strip cutting.

A Bezzerides cultivator was tried by a BASIC

grower during the 2002 season. The cultivator

works in the planted row where conventional

cultivators can.t reach. Traditionally,

this is the area where chemical herbicides

are used to eliminate competing weeds. The

trial was not considered a success, since the

cultivator also removes cotton plants along

with the weeds, and the growers who tested

the equipment felt that it was not significantly

better than their existing cultivators.

Seventy percent of the growers enrolled in

the 2002 BASIC program planted beneficial

habitat adjacent to their enrolled fields. The

habitat was intended to attract and hold naturally

occurring beneficials. The remaining

thirty percent of the enrolled fields were adjacent

to alfalfa fields where strip cutting was

practiced.

Releases of beneficial insects were also utilized

during the growing season. Thousands

of lacewings and predatory mites were released

to augment the naturally occurring insects.

When growers see a pest problem starting

to develop in their fields they want fast

action and so will often turn to a chemical

spray. Releasing insects helped them feel like

something was being done, while the natural

enemies took over the pest control.

For additional information on the Sustainable

Cotton Project or the BASIC program, contact

A trap crop is planted specifically to attract pest

insects. It is then sprayed with some type of insecticide,

in conventional management, or left to

detain the pests from the cotton crop, or the entire

trap crop is tilled under to kill the pest insects.

Early-sown cotton has been used as a bollweevil

trap crop. Using fall-planted-cotton trap

crops to reduce the number of over-wintering

boll weevils was first proposed as early as the

and fall cotton trap crops are effective at attracting

boll weevil adults and can be enhanced by

adding pheromones such as Grandlure. to the

trap crop. The concentrated weevils can then be

killed with organically accepted insecticides,

which are limited to a few botanicals and

biologicals. Crop consultants James and Larry

Chiles were able to reduce the cost of boll weevil

control by 30% using trap crops of early and lateplanted

cotton. Even with the cost reduction,

they were able to maintain good yields of 1000

to 1200 pounds per acre. They planted a trap

crop of cotton in early April, 30 days before the

normal cotton planting time, and a late-planted

trap crop on August 10. A weevil attractant

pheromone was used to lure boll weevils to the

cotton trap crops. The trap crops were sprayed

for weevils whenever populations were high.

This technique reduced the number of early

emergent weevils infesting the main crop and

reduced the number of weevils overwintering to

attack the next year.s crop. In a Mississippi study,

Oklahoma strip cropping study. Lygus bug may

also be kept out of cotton by using nearby alfalfa

as a trap crop. Unmowed or strip-mowed alfalfa

Strip cropping takes place when harvest-width

strips of two or three crops are planted in the

same field. The most common strip crop grown

with cotton is alfalfa. Increasing the diversity of

crops increases stability in the field, resulting in

fewer pest problems, due to natural biological

controls. Crop rotation is one means of introducing

diversity over time. Strip intercropping

creates biodiversity in space.

Strip cropping cotton fields with alfalfa generally

increases beneficial arthropod populations.

Among the most notable are carabid beetles that

best crops for attracting and retaining beneficial

insects. Strip-cutting alfalfa (i.e., cutting only half

of the crop in alternating strips at any one time)

maintains two growth stages in the crop; consequently,

some beneficial habitat is available at

all times. In some cases alfalfa is mixed with

another legume and a grass.

In a conventional cotton management study,

strips and 20-foot wide alfalfa strips to compare

pest control needs with monoculture cotton. The

intercropped field required only one insecticide

application, while the monoculture cotton had

to be sprayed four times. The practice was abandoned

in this specific case, however, due to modifications

to irrigation systems and extra labor to

cut alfalfa, which did not compensate for the reduced

pesticide costs.

Dr. Sharad Phatak of the University of Georgia

has been working with conventional cotton

growers in Georgia testing a strip-cropping

cotton into strip-killed crimson clover improves

soil health, cuts tillage costs, and allows

him to grow cotton without any insecticides and

only 30 pounds of commercial nitrogen fertilizer

per acre. Working with Phatak, farmer Benny

Johnson reported saving at least $120/acre on his

16-acre clover-system test plot. There were no

insect problems in the trial acres, while beet armyworms

and whiteflies were infesting nearby

cotton and required 8 to 12 sprayings. This system

may have some applicability in an organic

cotton system. In the study, cotton intercropped

with crimson clover yielded 5,564 pounds of seed

cotton per acre, compared with 1,666 pounds of

Boll counts were 30 per plant with crimson clover

and 11 without it. Phatak identified up to 15

different kinds of beneficial insects in these stripplanted

plots.

Phatak used a crimson clover seeding rate of 15-

pounds per acre that produced around 60 pounds

of nitrogen per acre by spring. By late spring,

beneficial insects were active in the cover crop.

At that time, 6- to 12-inch planting strips were

killed with Roundup. herbicide (not allowed

in an organic system). Fifteen to 20 days later

the strips were lightly tilled and the cotton

planted. The cover crop in the row-middles was

left growing to maintain beneficial insect habitat.

Even early-season thrips, which can be a

problem following cover crops, were limited or

prevented by beneficial insects in this system.

When the clover is past the bloom stage and less

desirable for beneficials, they move readily onto

the cotton. The timing coincides with a period

when cotton is most vulnerable to insect pests.

Following cotton defoliation, the beneficials hibernate

in adjacent non-crop areas.

Phatak emphasizes that switching to a wholefarm

focus while reducing off-farm inputs is not

simple. It requires planning, management, and

several years to implement on a large scale. It is

just as important to increase and maintain organic

matter, which stimulates beneficial soil

microorganisms.

Weedy borders are particularly infamous as

sources of insect pests. Current recommendations

suggest mowing them prior to establishment

of cotton. Mowing after weeds have

formed flower buds will tend to drive plant bugs

Grassy weed species harbor lepidopterous pests

generally. A specific weed, wild geranium, is an

important spring host of tobacco budworm and

should be discouraged in border areas.

More diverse field borders with habitat plant

species support some crop pests but also sustain

beneficial insects that prey on pest populations,

particularly during non-crop seasons. Managing

the vegetation in these areas as habitat for

beneficial insects counterbalances the threat from

insect pests. The strategy entails planting or otherwise

encouraging the growth of plants that

provide alternative food sources (nectar, pollen,

alternate prey), moisture, shelter, and perching

sites preferred by beneficials. Plant species that

are aggressive and invasive, or are known hosts

to major crop diseases or insect pests, should be

avoided. Descriptions of crops, cover crops, and

wild plants that are known to attract certain beneficial

insects and information on designing landscapes

to attract beneficial organisms can be

A naturally occuring fungal disease of aphids is

known to occur under conditions of high infestation.

In Mississippi, this historically occurs

commonly attack and suppress populations

of lepidopterous pests, most notably the cabbage

looper and beet armyworm. Suppression of these

pests by natural disease organisms is encouraged

by developing dense crop canopies, which also

assists in weed control. However, these are also

conditions that encourage plant diseases and

may not be desirable where cotton diseases are

rampant.

Early maturing crops are more likely to escape

damage from late-season infestations of boll

weevil, tobacco budworm, cotton bollworm, armyworms,

loopers, and other pests. The use of

short-season cotton is the most obvious means

of doing this. Excessive nitrogen use, late irrigation,

and excessive stand density can result in

delayed maturity and increased exposure to these

bacteria that produces a toxin effective in controlling

many caterpillars. The toxin causes paralysis

of the worm.s digestive tract. Worms may

continue to live for some hours after ingestion,

but will not continue to feed. B.t. strains have

been formulated into a number of commercial

rapidly in sunlight, requiring careful timing

or repeated applications.

B.t. must be ingested in sufficient amounts by

the caterpillar to be effective. Consequently, an

understanding of the feeding habits of the pests

is necessary, so that proper formulations are used

and timing of applications is optimal. Spray formulations

are most effective against armyworms

and those species feeding on exposed leaf surfaces.

budworm and moderately effective against

feeding habits, granular bait formulations are

more effective for control of cutworms. Careful

inspection of specific product labels will assure

that the product has been formulated for the pest

to be controlled.

commercially produced disease organism that

attacks budworms and bollworms. It has less of

a track record in the Southeast than B.t., but based

on preliminary observations it appears to be a

certain the formulation is cleared for use in organic

production.

fungus that has been formulated and is available

commercially. It works on several insect larvae,

including cutworms and budworms. It works

best during periods of high humidity. More on

this natural control method can be found below

in the Specific Insect Management Strategies section.

Evolved from a traditional organic gardening

technique, insecticidal soaps control insect pests

by penetrating the cuticle and causing cell membranes

to collapse and leak, resulting in dehydration.

Several commercial formulations of insecticidal

soap have been successfully used to

control aphids, spider mites, white flies, thrips,

leaf hoppers, plant bugs, and other pests. Soaps

have limited effects on chewing pests such as

beetles or caterpillars. Applied as sprays, these

biodegradable soaps work by contact only and

require excellent coverage to be fully effective

Insecticidal soaps will kill many beneficial insects

and must be used with that in mind. Phytotoxicity

has also been demonstrated, particularly on

varieties of cotton will have different plant characteristics.

Therefore, it is advisable to test the

soap solution on your plants on a small strip to

determine whether any harm will result. Avoid

application of soap during the heat of the day,

because the plant is then under extreme stress,

and you want the soap to remain on the plant as

long as possible, not evaporate rapidly. Late day

applications will stay on the plant longer, increasing

the chances of contact with target pests.

Water hardness will affect the efficacy of soap,

because calcium, iron, and magnesium will precipitate

the fatty acids and make the soap useless

against the target insects. The best way to

determine how well your water will work is the

soap-jar test. Let a jar full of your spray solution

sit for 20 minutes, then look for precipitates in

the soapy-water solution. Product labeling must

be studied to determine suitability to crop and

pest in each particular state and region.

Cutworms wreak havoc during seedling establishment

in many cotton-growing areas. Cutworm

species include the variegated cutworm,

night, feeding and chewing through the stems

of the seedlings. In the day they burrow underground

or under clods to avoid detection. To

inspect for cutworms, dig around the damaged

areas during the day or come out at night with a

flashlight to catch the culprits in the act. Problem

areas are usually found near field borders

and in weedier areas.

Cutworms have many predators and parasites

that can help control their numbers. Some of

these parasites and predators can be purchased

or harnessed naturally through planting or conserving

habitat for them.

Understanding the biology of beneficial organisms

is imperative in order to use them effectively

as pest control agents. For example, insect parasitic

adequate humidity to be effective. Other predators

include spiders, minute pirate bugs, damsel

bugs, and lacewing larvae. Birds also prey on

cutworms, so do not assume that the birds in the

field are causing the seedling damage.

If natural pesticide applications are necessary,

choose one that is least disruptive to the natural

enemies. The application of a rolled oats with

Again, early detection and application

during the early developmental stages of the larvae

pesticides more effective. Pheromone traps will

indicate when mating flights are occurring, and

through degree-day calculations one can estimate

egg laying and hatching. For information on degree-

day calculations contact your local Extension

agent.

Thyme oil serves as a toxicant, insect growth

regulator, and antifeedant to cutworms

larval growth and is insecticidal to the cutworms

using tyme oil, mock lime, or Chinese rice flower

are known to us at this time. Azadirachtin, the

active ingredient in neem, has similar effects on

various insects and is used in the form of neem

cakes to control soil pests in India. Certis USA

produces Neemix Botanical Insecticide. Its active

ingredient, Azadirachtin, is registered for

cutworm, looper, armyworm, bollworm, whitefly,

and aphid control on cotton.

bolls, squares, and blooms, and feeding on

plant terminal buds, causing branching that delays

maturity. On mature damaged bolls, one

finds holes with excrement or frass surrounding

the boll. These holes provide entry to secondary

organisms that can cause decay. Besides cotton,

other bollworm hosts include alfalfa, beans, corn,

peanuts, sorghum, soybeans, peppers, sweet

potatoes, tobacco, and tomatoes. Wild hosts include

toadflax, deergrass, beggarweed,

groundcherry, geranium, and sowthistle. In

feeding preference tests, 67% of females preferred

common sowthistle, about 5% preferred cotton,

and 28% did not discriminate. Common

sowthistle was also the most preferred by newly

hatched larvae among the five host plant types

strategies using sowthistle as a trap

crop.

This bollworm .complex. has many natural enemies

that can be harnessed through the use of

beneficial habitats or purchased from insectaries.

Generalist predators such as assassin bugs,

bigeyed bugs, damsel bugs, minute pirate bugs,

lacewing larvae, collops beetles, and spiders will

feed on the eggs of bollworm or on the larvae

that are in early stages of development. Parasites

pupae. These groups of natural enemies are usually

enough to keep bollworms below economically

damaging thresholds. In conventional

fields where broad-spectrum insecticides are

used, these natural enemies are so depleted that

continuous spraying is required to keep bollworms

and other pests in check.

Cultural practices that keep bollworm numbers

down include managing the cotton field to obtain

an early harvest and avoiding over-fertilizing

or over-watering. Tillage significantly lowers

bollworm populations by disrupting emergence

from the overwintering stage. Minimum

tillage operations may favor bollworm populations,

except in the South, where minimum tillage

favors fire ant colonization (Monks and

Patterson, no date). Fire ants are effective predators

of many cotton pests, including bollworm.

they need to be timed so that the bollworm

larva is in its early stages of development

the exposure to the B.t., since ultraviolet rays of

bollworm only when temperature and humidity

requirements are met. Research from China indicates

that the ideal temperature and humidity

drastically decreased when humidity dropped

virus, another biopesticide, is a diseasecausing

virus for use on the bollworm complex

and is available commercially in a product call

Gemstar LC. from Certis USA. Azadirachtin,

the principal active ingredient in many neembased

products, also shows promise as a growth

regulator and anti-feedant against the cotton

as they are commonly called.is a significant

cotton pest in the Southwest. They have also

been found in Texas, Oklahoma, Arkansas, and

Florida. Pinkies damage cotton by feeding on

buds and flowers and on developing seeds and

lint in bolls. Under dry conditions, no measurable

yield reduction occurs until 25 to 30% of the

bolls are infested; at this level the infested bolls

have more than one larva. With high humidity,

it takes only one or two larvae to destroy an entire

boll, because damaged bolls are vulnerable

that develops around the hole where pinkies

have entered. Unlike cotton bollworm or tobacco

budworm, pinkies do not deposit frass or feces

at the base of the entrance hole.

Cultural practices to reduce pink bollworm numbers

consist of ceasing irrigation sooner than

normal, early crop harvest, shredding crop residue

after harvest, plowdown of cotton residue

to six inches, and winter irrigation if cotton will

follow cotton on the same field (not a wise practice

in organic production). Okra and kenaf are

alternate hosts to pink bollworm and must also

be eliminated from an area. These techniques

are used in area-wide eradication efforts. Areawide

sterile release programs through the Animal

and Plant Health Inspection Service (APHIS)

of the USDA is a biological control method also

used in eradication efforts.

Pink bollworm eggs are very small, making them

susceptible to many natural enemies, including

mites, spiders, minute pirate bugs, damsel bugs,

bigeyed bugs, and lacewing larvae. A number

have shown that the use of the insect-feeding

on pink bollworm larvae in the fields achieved a

to correlate with hatching and early stages

of development of the pink bollworm, as well as

optimum humidity for the fungi to infect.

Other strategies to reduce pink bollworm populations

include the use of mating pheromone

disruptors. Several products, such as Biolures®,

Checkmate®, Frustrate®, and PB Rope®, are

available in the U.S. Pink bollworm mating disruption

trials recorded higher yields (1864 lbs/

acre) than control fields with no mating disruption

cotton and on rare occasions cause yield reductions.

Beet armyworms can cause yield reductions

in cotton if populations are high enough

near the end of the season. Armyworms hatch

in clusters, with the small worms spreading

through the plant over time, feeding on leaves,

squares, flowers, and bolls. They skeletonize

leaves and bracts, trailing frass and spinning

small webs as they go. The egg clusters are covered

with white cottony webbing, making them

easy to spot. Outbreaks are attributed to favorable

weather conditions and the killing off of

natural enemies.

Natural enemies are assassin bugs, damsel bugs,

bigeyed bugs, lacewing larvae, spiders, the parasitic

Nuclear polyhedrosis virus is a disease-producing

virus that infects beet armyworm. It is available

is thorough. Laboratory and greenhouse

tests showed that caffeine boosted the effectiveness

of the B.t. against armyworms up to

against pests that are weakly susceptible to

B.t. itself. Recipe: dissolve 13 oz. pure caffeine

in water; add the solution to 100 gallons of standard

Caffeine can be obtained from most chemicalsupply

houses and is also available in pill form

from most pharmacies. Organic growers interested

in this approach should ask their certifying

agency about the appropriateness of this

treatment in a certified organic system.

Many other crops are hosts to armyworms, as

are the weeds mullen, purslane, Russian thistle,

crabgrass, johnsongrass, morning glory,

lambsquarters, nettleleaf goosefoot, and pigweed.

These last three are preferred hosts that

can serve as indicators of the populations or be

managed as trap crops.

areas between veins causing a net-like appearance

but rarely cause significant damage, because

natural enemies control them. If the enemies are

lacking in number, severe defoliation of cotton

plants by loopers may cause problems with boll

maturation. Defoliation before bolls mature can

reduce yields drastically.

Loopers feed on all the crucifers, crops and

weeds, and on melons, celery, cucumbers, beans,

lettuces, peas, peppers, potatoes, spinach, squash,

sweet potatoes, and tomatoes. Other hosts include

some flowers, like stocks and snapdragons,

and tobacco. Some weed hosts include

lambsquarters, dandelion, and curly dock.

Natural enemies are assassin bugs, bigeyed bugs,

damsel bugs, minute pirate bugs, lacewing larvae,

spiders, and numerous parasitic wasps, such

virus) sometimes is responsible for sudden

looper population decline, especially after

the problem is detected early.

Thrips damage seedlings by rasping and sucking

the surface cells of developing leaves, resulting

in twisted and distorted young leaves. They

are rarely a problem and are usually kept in check

by minute pirate bugs, parasitic wasps, predacious

mites, and other thrips. The western flower

thrip can be a beneficial insect when it feeds on

spider mites on a full-grown plant. The bean

leaves and sometimes causes defoliation. Insecticidal

soap is the least toxic pesticide for thrips

but should not be applied on hot sunny days

because it may burn the plants. Research has

demonstrated that cotton varieties with hairy

leaves are less injured by thrips than smooth-leaf

Wayne Parramore of Coolidge, Georgia, strip

crops cotton into lupine, providing him with nitrogen,

soil erosion control, and a beneficial insect

When the lupine is 36 inches tall, a strip is tilled

14 inches across the seedbed. A Brown plow in

front of the tractor with a rotovator in the back

exposes the center strip, warming it up for the

planting of cotton. The remaining lupine is host

to aphids, thrips, and their natural enemies. It

prevents weeds and grasses from growing up

and it reduces soil erosion. The remainder of

lupine that is tilled in later provides a second shot

of nitrogen to the cotton. The Parramores report

that strip tilled cotton-lupine required only two

insecticide applications. They later determined

that they could have done without the second

spraying in the lupine field, based on a checkplot

comparison. Neighboring conventional

fields took five spray applications.

is a small bug measuring about 1/8 inch, with

black specks covering its yellowish-green body.

stinging the squares, which then drop from the

plant, reducing yields. In 1999 the cotton fleahopper

was the most damaging insect in cotton,

responsible for nearly a third of the total reduction

in yield caused by all insect pests in the U.S.

Total U.S. insect losses represented more than

fields near weedy and uncultivated ground or

near weedy borders. Some of these weeds, like

that have been shown to be preferred by

and dry out, the pests will move to the cotton.

This information can help with monitoring and

establishing a trap crop system. Natural enemies

of fleahoppers include assassin bugs, bigeyed

bugs, damsel bugs, lacewing larvae, and spiders.

A study done in east Texas showed that spiders

were three times better than insects as predators

The first three species are found in the Southwest,

cotton belt. They pierce stems and suck plant

juices, causing damage to flower buds (squares),

young bolls, and terminal buds. Because almost

any plant that produces a seed head can be a lygus

host, this pest has a wide range. Cotton is

not the preferred host of lygus, but once the surrounding

vegetation starts to dry up, they will

move into irrigated cotton and feed on succulent

plant parts. Alfalfa is a preferred host to lygus

and can be grown in strip intercrops with cotton

to assist in lygus control. The classic habitat

manipulation system where alfalfa is strip harvested

or where borders are left uncut demonstrates

that lygus can be kept away from cotton

during critical square formation. The alfalfa also

harbors numerous natural enemies of lygus,

keeping their populations in check. These natu-

.By having these crop strips in my field, I have

insects evenly distributed . nonbeneficials

feeding beneficials. Now when the cotton gets

big enough for the legume to die, where are

the beneficials gonna be? They.re not going

to be all around the edges of the field and

slowly come across the field; they.re all over

the field already. They.re in the middle where

lupine is still growing inches away from cotton

plants. We.re looking at a savings and

increase in production of approximately

$184.50 per acre..

which parasitizes lygus eggs, and predators like

damsel bugs, bigeyed bugs, assassin bugs, lacewing

larvae, and spiders. If lygus populations

are reaching economically damaging levels, then

a pesticide application is warranted. Check with

your organic certifier to determine which pesticides

are allowed. Botanical insecticides such as

pyrethrum, sabadilla, and rotenone are options

but may be prohibitively expensive. Insecticidal

soaps can reduce the lygus nymph population.

Keep in mind that these treatments will also affect

the natural enemies and may cause secondary

outbreaks of pests like aphids and mites.

by some as the primary deterrent to growing

cotton organically. In weevil eradication

zones, the boll weevil may be less of a concern.

Conventional controls consist of applying pesticides

to target the adults when they start feeding

and laying eggs. For organic systems, using

this approach with organically accepted pesticides

would be too costly and only moderately

effective.

The use of short-season cotton may be part of an

overall strategy to control boll weevils with little

or no sprayed insecticides. The objective of shortseason

cotton is to escape significant damage

caused by the second generation of weevils,

through early fruiting and harvest. For this to

occur, the population of first generation weevils

must also be low. Crop residue management and

field sanitation is essential. Destruction of cotton

stalks soon after harvest has long been recognized

as a useful practice for reducing the

Early harvest, sanitation, and immediate

plowdown are strategies that keep the overwintering

populations low for the following season.

In order for these strategies to be effective, they

must be practiced by all cotton growers in an

area. Any volunteer cotton plants that are missed

can be the source of infestation for the following

crop season.

The boll weevil has two effective insect parasites,

can contribute to boll weevil control if conditions

are favorable and suitable habitats are available.

Mexico but has been effective in controlling boll

weevils in augmentative releases done in USDA

cooperative studies. The researchers achieved

per acre per week over a nine-week period.

The objective was to suppress or eliminate

weevil reproduction in six organic cotton fields.

instar weevils. The use of augmentative releases

and enhancing available technology for

commercially available.

Other alternative methods used by organic cotton

growers in Texas against the boll weevil are

pyrethrum used with diatomaceous earth, garlic

oil and fish emulsion as repellants, and pheromone

traps for early detection. For more information

on Texas organic cotton growers and the

boll weevil eradication zones, check the Web site:

http://www.texasorganic.com/BollWeevil.htm

Aphid problems in conventional cotton are usually

the result of secondary pest flair ups caused

by excessive spraying for a primary pest like lygus

or bollweevil, because the broad-spectrum

insecticides also kill the beneficial insects.

Aphids are usually kept below economically

damaging levels by predators like the ladybug,

syrphid fly larva, lacewing larva, minute pirate

The damage caused by aphids and other homopterans,

like whiteflies, comes from their honeydew

excretion that contaminates the lint and

causes sticky cotton. A study conducted in

Georgia.s coastal plain indicates that aphids are

initially suppressed by the insect-eating fungus

thereafter by parasitoids and predators, most

notably the small lady beetles of the Scymnus

The choice of cotton varieties influences the abundance

of cotton aphids and their associated

biological-control agents. A study comparing

cotton varieties found lower aphid densities on

cotton varieties exhibiting the smooth-leaf characteristics.

Parasitism and predation may have

reduced cotton aphid population growth early

in the season. Disease-causing fungal infection

was the primary cause of an aphid population

reduction that occurred during the week after

peak aphid abundance, and continued disease

activity combined with predation maintained

aphids at a low density for the remainder of the

Nitrogen management is an important tool in

controlling aphid infestations, though less easily

done without commercial fertilizers. Studies

have shown that excessive or poorly timed fertilizer-

N application will promote tender and

succulent plant growth that attracts aphids. In

California, experiments showed that cotton

aphids reached higher densities in high nitrogen

fertilized plants (200 lbs. N/ac.) than in low nitrogen

has also increased insecticide application,

from an average of 2-3 to 4-6 or more per season

The concept of induced resistance in plants has

generated much interest in alternative pest control

circles recently. Plants can be treated with

substances that induce resistance to plant pests.

One of these substances, jasmonic acid, has been

used on cotton to determine the effect it has on

cotton aphid, two spotted spider mites, and western

flower thrips. Preference was reduced by

more than 60% for aphids and spider mites, and

by more than 90% for thrips on jasmonic-acidinduced

leaves compared with control leaves

jasmonic acid is an essential oil isolated from the

with the application of jasmonic acid also

attracts natural enemies. Other plant resistance

inducers include salicylic acid (aspirin) and salts

like potassium phosphate and potassium silicate.

Amino acids such as beta-aminobutryic acid and

botanicals such as the extract of giant knotweed,

product made from giant knotweed extract.

Check with your certifier before applying

any of these products.

Whiteflies are similar to aphids in that they pierce

stems and suck plant sap then excrete honeydew

that contaminates the lint. The adult whiteflys

resemble tiny white moths, the nymphs are more

like scale insects. They are found on the undersides

of cotton leaves, and when their numbers

are high enough, the honeydew falls to leaf surfaces

below where sooty mold forms, turning the

leaf black. Whiteflies are usually kept in check

by natural enemies, unless broad-spectrum pesticides

are applied for a key pest. If most predators

and parasites are killed, then the potential

for devastating outbreaks exists. Beneficial insects

that prey on whiteflies are lacewing larvae,

lady beetles, minute pirate bugs, and bigeyed

more than one whitefly species. These nymphs

are what most predators and parasites attack.

If whitefly populations near threshold levels, use

insecticidal soap or .narrow range. oil (check

with your certifier to determine which oils are

allowed) to reduce primarily the nymph and

pupa stage of the whitefly. Botanical insecticides

like neem can reduce adult populations and also

act as an insect growth regulator affecting the

pupal stage. Other botanical insecticides such

as pyrethrum can help reduce the adult population.

humidity. An effective sprayer that has enough

power to cover both sides of the leaf surface is

needed, and at least 100 gallons of water per acre

is necessary to have sufficient coverage.

In conventional cotton, nitrogen fertilizer management

is also a factor in whitefly population

levels and the amount of honeydew produced.

A California study demonstrated that increasing

levels of nitrogen fertilizer increased densities of

both adult and immature whiteflies during their

peak population growth on cotton. Higher nitrogen

treatments also resulted in higher densities

of honeydew drops produced by the whiteflies

(related to spiders, ticks, and scorpions) that live

in colonies, spinning webs and feeding under

cotton leaves. Spider mites have modified mouth

parts that pierce the cells of the leaf to consume

its contents. On the leaf.s upper surface yellow

spots appear when the feeding is moderate. Once

the plants are infested, the yellow spots turn reddish

brown. If the infestation is severe, mites

can cause defoliation and affect yields. Spider

mite populations are usually suppressed by natural

enemies, unless a broad spectrum insecticide

application occurs to disturb this balance. Insect

predators of spider mites include minute pirate

bugs, damsel bugs, bigeyed bugs, some midges,

lacewing larvae, dustywings, spider mite destroyers,

lady beetles, sixspotted thrips, and western

flower thrips. Other mites that prey on spider

scouting for mites, a hand lens is necessary to

distinguish the pest mites from the predatory

mites. Spider mites tend to be sedentary, while

their predators are very active.

Insecticidal soaps, .narrow range. oils, neembased

products such as Trilogy®, and sulfur are

acceptable miticides in organic production (check

with certifier regarding specific products). Application

instruments must thoroughly cover the

leaves. undersides, and products that are diluted

must be applied in high volumes (more than 100

gallons of water per acre) to achieve complete

coverage.

Cultural controls include keeping dust down

along roads that border cotton fields. This is usually

done by reducing traffic along those roads

or watering down the roads. Reducing water

stress on the cotton plants helps prevent mite

build up. Pima cotton varieties are less susceptible

Diseases in plants occur when the pathogen is

present, the host is susceptible, and the environment

is favorable for the disease to develop.

Eliminating any one of these three factors will

prevent the disease from occurring. Organisms

responsible for cotton diseases include fungi,

bacteria, nematodes, and viruses. If these organisms

are present, then manipulation of the environment

and the host, to make it less susceptible,

helps to better manage diseases on cotton in a

sustainable manner.

Soil health and management is the key for successful

control of plant diseases. A soil with adequate

organic matter can house uncountable

numbers of organisms such as bacteria, fungi,

amoebae, nematodes, protozoa, arthropods, and

earthworms that in conjunction deter harmful

fungi, bacteria, nematodes and arthropods from

attacking plants. These beneficial organisms also

help in creating a healthy plant that is able to

resist pest attack. For more information, see the

The leaf surface can also host beneficial organisms

that compete with pathogens for space. A

disease spore landing on a leaf surface has to find

a suitable niche for it to germinate, penetrate, and

infect. The more beneficial organisms on the leaf,

the greater the competition for the spore to find

a niche. Applying compost teas adds beneficial

microorganisms to the leaf, making it more difficult

for diseases to become established. For

more information on foliar disease controls, see

These diseases are soil-borne fungi and are associated

deep seed placement, soil compaction, and cool

temperatures contribute to seedling disease development.

Spreading compost and using green

manure crops, especially grasses, can reduce the

pathogen levels in the soil. Various organisms

have been researched as potential biological

rhizobacteria, and fluorescent pseudomonads as

commercially in a product called Deny®.

under the trade name Kodiak®, is recommended

as a seed inoculant for controlling damping off

fungi. The following organisms have been used

as soil treatments with varying levels of success:

The three most important fungal soil diseases

microscopic, worm-like animals. Only a few species

are damaging to cotton. They will be classified

in this publication as a soil disease.

but when associated with nematodes, it forms a

complex in which the nematode damage weakens

the plant, making it susceptible to the fungus.

Organic matter and its associated microorganisms

can serve as an antagonist to this disease.

(Kodiak®) as a seed inoculum is recommended.

The strategies for nematode control will be discussed

further on in this publication.

and the Southwest. It is difficult to control and

occurs on more than 2,300 broadleaf plants

temperatures and in low organic-matter soils, so

adding compost or incorporating green manure

crops will increase organic matter and microorganism

competition. Avoid growing cotton on

ground that is known to harbor this disease.

widespread, attacking many other agronomic,

horticultural, and ornamental crops, as well as

some weeds. It is persistent in the soil because

of survival structures called microsclerotia.

These microsclerotia are produced throughout

the infected plant and when the crop is disked,

these seed-like structures are also incorporated

into the soil. Cultural controls include resistant

varieties (Pima cotton is tolerant), rotation with

grass crops, management for short season production,

and avoiding excessive nitrogen and irrigation.

Soil solarization done 6-11 weeks before

planting was effective in one study where

the pathogen was reduced to negligible levels

There are many types of nematodes in soils, most

are beneficial, and a few are cotton pests. Where

nematode infestations are heavy, sampling and

laboratory analysis can be used to determine the

length of rotations and the non-host crops to use.

If the problem is root-knot nematodes, rotation

to resistant soybean varieties or sorghum is a

possibility. Rotation to wheat, corn, grain sorghum,

or resistant soybeans is possible if the

cotton are the root knot nematode,

production systems, nematodes can be managed

by crop rotation, resistant varieties, and cultural

practices. Eventually a .living soil. will keep

harmful nematodes and soilborne fungi under

strategy, but make sure to identify the type of

nematode you have and rotate with a crop that

is not an alternate host for that nematode. For

example, the reniform nematode also feeds on

vetch, tobacco, soybeans, tomatoes, and okra, so

these crops are not suitable for rotation with cotton

for reniform nematode reduction. Check

with your seed supplier to identify varieties resistant

to the nematodes present in your field.

Cultural practices include cover cropping with

plants that are antagonistic to nematodes, such

as rapeseed or marigolds, planting cotton on soils

that are less sandy, controlling weeds, incorporation

of chicken litter and other manures, and

solarization. For more information, see the

Boll rots are a problem in areas with high humidity

and rainfall and where bolls are starting

to open or have been damaged by insects. Most

pathogens are secondary invaders relying on insect

a basal type of rot where bracts are infected first,

followed by invasion through nectaries and the

also responsible for foliar diseases. The boll-rot

which produces aflatoxins in the cottonseed.

Aflatoxins are carcinogens to some animals and

to humans. It contaminates cottonseed oil and

cottonseed meal, which then cannot be used for

consider cultural practices that reduce humidity,

such as lower density seeding to allow more

air circulation. Avoid tall, vegetative cotton

growth.often a result of late planting, excessive

nitrogen fertilizer, fertile soils, and/or excessive

moisture. Rank growth often renders cotton

plants more attractive and susceptible to late season

insects, more susceptible to boll rot, and more

wet weather during the growing season. It

causes defoliation and reduces lint quality. Leaf

spots are angular, restricted by leaf veins, watersoaked

when fresh, and eventually turning

brown before defoliation. Boll symptoms are

small, round, water-soaked spots that become

black. Affected bolls may shed or fail to open

and have poor-quality lint. Quick plow down of

crop residues after harvest to give ample time

for decomposition will assist in the control of the

disease. Crop rotation and using resistant varieties

are also effective strategies.

enlarges to half an inch. Concentric rings form

as the spot enlarges, with the center sometimes

falling out to form a shothole. Spots can also be

found on bolls. High humidity increases the incidences

of the disease, causing defoliation in severe

cases. Controls include using resistant varieties

and avoiding prolonged leaf wetness.

appears as small, yellowish spots on leaves,

stems, and bolls, usually after a rain. These spots

enlarge, developing orange-reddish to brown

centers. Later, large orange spots appear on the

lower leaves and discharge orange spores. Rust

diseases require more than one host in order to

its proximity to the cotton field may determine

the severity of infestation. If there is grama grass

near your field, removal by burning, plowing,

or grazing is recommended. A season of heavy

rains and high humidity with grama grass close

by has the potential for problems with cotton rust.

Cotton leaf crumple virus is transmitted by the

of the vector and stub cotton, which serves as an

overwintering site for the virus, and the use of

resistant varieties are strategies for disease reduction.

Symptoms include wrinkled leaves that are

cupped downward and plants that are small or

stunted. This disease causes economic losses if

the plants are infected when young.

Defoliation is a significant obstacle to organic

production. The organic options available to

defoliate cotton include flame defoliation and

waiting for frost. Vinegar has not been cleared

for use as a defoliant under the NOP rules. Ceasing

irrigation can assist in leaf drop and boll

maturation in low rainfall areas. Citric acid has

been used by at least one Missouri cotton farmer

if it comes from natural sources. Otherwise,

the only alternatives are to wait for a frost

or hand harvest.

Research reports from the 1960s show that considerable

work was devoted to developing butane-

gas flame defoliators. Several models were

developed by engineers in various parts of the

cotton belt. To our knowledge no such equipment

is available on the market today, having

been replaced by chemical defoliation methods.

As previously mentioned, marketing cotton as

.organic. requires certification of the field production

practices. Certification also must continue

throughout the manufacturing process,

from the ginner, yarn spinner, and cloth maker,

to the garment manufacturer. Each step of the

process must use only materials (dyes, bleaches,

etc.) that meet organic specifications. Manufactured

products that are not already on the National

Organic Program.s approved list must go

through a lengthy process to gain approval. If

any unapproved product is used in the processing

of cotton, the fiber cannot be labeled as organic

Organic cotton farmers usually sell either to a

mill or a manufacturer. It is usually up to the

farmer to negotiate the price with his buyer.

Buyers of organic cotton are limited. Parkdale

cotton buyer in the U.S. Located in

Belmont, North Carolina, Parkdale makes yarn

from organic cotton. They buy mostly from the

southern states and occasionally from California.

They purchase organic cotton when demand

from a garment maker warrants. They buy from

farmers, co-ops, and merchants.

Sandra Marquardt of the Organic Trade

price premiums range from around $.95 to $1.25

per pound, depending on the quality and staple

length. This premium may decline as stiff competition

from foreign organic cotton increases.

The Organic Fiber Council lists companies that

could be approached as potential buyers of organic

cotton, especially the mills.

The International Organic Cotton Directory offers

an extensive listing of people, companies,

and farmers involved in the organic cotton industry.

They are dedicated to the sustainable

production, processing, and consumption of organic

cotton worldwide. They have directories

listed by product type, business type, and alphabetically.

There are a number of U.S. merchants/

brokers and eight U.S. mills listed that could be

potential buyers of organic cotton. As well, there

are several farmers and farm organizations listed

that are involved with organic cotton. See this

Results from a six-year study in the San Joaquin

cotton production costs running approximately

50% higher than those of conventional

cotton. The researchers found no difference between

fiber length, strength, or micronaire between

conventional and organic cotton. They

concluded that organic cotton production was

feasible in the northern San Joaquin Valley and

that effective marketing of organic cotton must

include a price premium to offset higher production

costs.

Costs that typically differ from conventional cotton

production include fertilizer materials such

as manure, compost, or cover crop seed and their

associated application and establishment costs;

mechanical weed control costs; organically-acceptable

insect and disease management materials,

such as compost tea and beneficial insects;

additional hand weeding labor; and costs associated

with being certified organic.

A detailed organic cotton budget is available

from The University of California Extension Service.

To locate this publication on the Web go

costs/95/cotton.htm

Prospective growers should be aware that growing

organic cotton is not quite the lucrative

proposition it sounds and that there may be more

money made, and less risk involved, in growing

other crops instead. Cotton has many pests that

must be controlled without conventional pesticides

under an organic system. Weed control

options are limited to those done without synthetic

herbicides. Defoliation can be a major challenge,

with limited options to accomplish the

task. Transitioning from conventional crop production

to organic cotton is fraught with risk, not

to mention that the transition process takes three

years before the fields can be certified as organic.

Additionally, in the absence of institutional support

and infrastructure, organic growers are unable

to move organic cotton around as easily as

do conventional growers. Markets for organic

cotton are limited, and demand plus foreign supplies

ton is grown in the northern fringe of the Cotton

Belt, out of the main range of the boll weevil.

With weevil eradication programs, however, organic

cotton may have a better chance than before

to produce well throughout the Cotton Belt.

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The Organic Cotton site:

http://www.sustainablecotton.org/

Details on a Texas organic cotton farm:

http://www.sosfromtexas.com/

International Organic Cotton Directory:

http://www.organiccottondirectory.net/

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