Crop Profile for Cotton in Mississippi

Prepared March, 2002

For many years cotton has been Mississippi's leading row crop. Even with recent acreage reductions , Mississippi is still among the top five cotton producing states in the nation.

Records of acreage and production have been kept since 1866. The record highest yield was recorded in 1997 at 901 pounds of lint per acre. The record lowest yield per acre occurred in 1866 at 86 pounds of lint per acre. The record highest acreage occurred in 1930...4,136,000 acres. The record lowest acreage occurred in 1982...680,000 acres. The record high production occurred in 1937 at 2,692,000 bales. The record low production occurred in 1866 at 320,000 bales.

Typically Mississippi ranked second in acres behind Texas, third in yield per acre behind California and Arizona, and third in total bales produced behind Texas and California. Recently, due to acreage increases after boll weevil eradication, Georgia has exceeded Mississippi acreage and production. In 1998, cotton production ranked Number 4 in the United States and led all crops in Mississippi with cash receipts of $585 million.

In 1999, cotton in Mississippi was valued at $481.1 million, the average yield was 708 pounds of cotton per acre. There were 1,180,000 acres planted in 1999 producing 1.74 million bales.

Cotton requires large investments of capital, labor and management. However, cotton can return tremendous economic benefits to growers, the community and the state. There are also risks associated with the production of cotton. These risks, low prices and reduction is governmental support, resulted in growers reducing acreage. In 1995, Mississippi harvested 1,420,000 acres as compared to 970,000 acres in 1997 and some 916,000 acres in 1998.

In 2000, there were 1,300,000 acres planted which yielded 642 pounds per acre. In 2001, there were 1,800,000 acres planted which yielded 708 pounds per acre.

Production Regions

Cotton is primarily grown in three areas of the state: North Delta, South Delta and Hills with spotted acres in a few southern counties.

Worker Activities

Insect Scouting: Scouting for insects and monitoring plant development is the primary activity requiring pedestrian workers to enter cotton fields during the growing season. Scouting is performed by professional crop consultants and summer scouts (usually high school or college aged individuals) employed by these consultants, as well as by producers and industry fieldmen. Full time cotton scouts normally work in excess of 40 hours per week and much of this time is spent walking through cotton fields, counting insects and collecting information on plant development. Ideally, cotton is scouted twice weekly from emergence through the boll opening period. Full time cotton scouts are in direct contact with plants for a large portion of the day each work day of the growing season.

Irrigation: Approximately 21% of the cotton in Mississippi is furrow irrigated. Irrigation pipe must be placed in fields after all tillage operations are completed for the season and removed before harvest. This requires pedestrian workers to enter fields at least twice during the growing season to place and remove pipe. Workers may also be required to enter fields during the irrigation process, to make repairs and to manage the irrigation procedure. Workers performing such irrigation procedures may be in direct contact with plants, but this occurs during a limited portion of the season.

Hand Weeding: Hand weeding is uncommon, but is still performed occasionally by workers who are chopping weeds or 'spot spraying' with a hand carried sprayer. Workers performing such procedures are in direct contact with plants for a large portion of the time period during which the procedure is being performed, but this occurs during a limited portion of the season.

Tillage, Spraying, and Harvest: Individuals performing normal cultivation, spraying and/or harvest operations are operating motorized equipment, usually from an enclosed cab. Occasionally, it is necessary for equipment operators to dismount in the field to perform minor repairs, such as adjusting cultivators or unclogging spray nozzles. Workers are in direct contact with plants during the time that they are dismounted, but this represents only a small portion of the work day.

Integrated Pest Management

Cotton in Mississippi is attacked by more than a dozen different species of insect pests. Table 1 provides a list of the most common pests of cotton and a brief description of the damage they cause. Each of these pests is capable of causing economic yield loss, and some, such as the tobacco budworm, are capable of totally destroying a crop. Historically the bollworm/tobacco budworm complex has ranked as one of the most damaging pests of Mississippi cotton, but boll weevils, tarnished plant bugs, beet armyworms, fall armyworms, cotton aphids, and thrips have also caused high levels of damage in some years (Table 2).

Cotton growers may invest more than $500 to produce an acre of cotton, and all of this investment is potentially at risk to insect damage. The cost of controlling insects is one of the larger items of the crop production budget, annually averaging from $70 to over $100 per acre (Figure 1).

Integrated pest management (IPM) is practiced on all of Mississippi's cotton acreage. Producers utilize a variety of non-insecticidal management tools (Table 3) to limit the number of times that pests exceed economic thresholds and consequently require treatment with insecticides. However, timely judicious use of insecticides is an important component of cotton IPM. Recommendations for cotton insect management are published in the Cotton Insect Control Guide, which is revised annually to incorporate the latest technology and research. Table 4 lists the insecticides recommended for use in Mississippi cotton and the pests for which they are recommended.

Because pest populations can change quickly, cotton insect management is both information intensive and time sensitive. During the growing season, fields must be scouted every three to four days, and accurate estimates of pest populations must be determined by time consuming sampling procedures. Because of the time involved in making these counts, most Mississippi producers contract the services of a professional crop consultant, usually for a 'per acre' scouting fee, to monitor insect populations and make treatment recommendations.

During recent years there have been significant changes in Mississippi's cotton IPM system, and this system continues to evolve rapidly. These changes are occurring because of three major factors: transgenic Bt-cotton, boll weevil eradication, and new, more target specific insecticides.

In recent years from 70 to 80% of Mississippi's cotton acreage has been planted to Bt transgenic cotton varieties. Because Bt cotton is highly effective against tobacco budworm, fields planted to Bt varieties do not require treatment for this pest. Bt cotton is also effective against bollworms, but to a lesser degree, and Bt fields occasionally require treatment for control of bollworms. However, since Bt-cotton was first introduced in 1996, Bt fields have consistently required fewer treatments than non-Bt fields for caterpillar pests, while also sustaining less boll damage (Table 5).

Mississippi began boll weevil eradication efforts in 1997 in the Eastern portion of the state. In 2001, the Hill Region of Mississippi was in the 5th year of Boll Weevil Eradication Program and the South Delta and North Delta were in the fourth and third year, respectively. Although Mississippi has not yet achieved the goal of eradicating this pest, overall boll weevil numbers were extremely low in 2001, and no yield loss was attributed to boll weevils. Only 32% of the acres in the state required treatment for boll weevils and most of these treatments were applied late in the season, when they would be less likely to flare secondary pests. Progress of the boll weevil eradication effort has had a tremendous positive impact on Mississippi's Cotton IPM program, and has resulted in a sharp decrease in the number of insecticide applications applied by growers (Figure 2).

During the past several years a number of new insecticides, belonging to novel classes of chemistry, have been developed, or are being developed, for use in cotton. These include products such as spinosad (Tracer), indoxacarb (Steward), and thiamethoxam (Centric). While these products are quite effective against their primary target pests, they tend to control a narrower spectrum of pests than most of the older products. This can be advantageous, when there is a need to control only one pest, because the increased selectivity fosters conservation of beneficial insects. However, when there is a need to control multiple pest species, the need to tank mix multiple insecticides can offer distinct economic and ecological disadvantages.

Together, the broad adoption of transgenic Bt cotton, combined with the progress of the boll weevil eradication effort have resulted in significant reductions in the number of foliar sprays applied by Mississippi cotton producers (Figure 2). Unfortunately, this reduction in the number of foliar insecticide treatments has not provided a corresponding decrease in the per acre cost of cotton insect control (Figure 1). This is because of offsetting costs associated with 'technology use fees' for Bt cotton, assessment fees to fund boll weevil eradication efforts, and increased costs of newer insecticides. Still, boll weevil eradication and Bt cotton have had the very positive impacts of reducing the risks of insect induced yield losses, reducing overall use of insecticides, and reducing the physical and logistical effort that growers must devote to insect management.

One consequence of this new pest management system under which cotton is grown in Mississippi has been a shift in the overall pest complex. Pests such as boll weevils and tobacco budworms are of much less concern that they had been in past years, because of the direct effects of boll weevil eradication and Bt-cotton. The reduction in foliar sprays has also had an indirect effect in reducing outbreaks of secondary pests, such as cotton aphids and beet armyworms. However, pests such as tarnished plant bugs and stink bugs have thrived in this reduced spray environment and the number of treatments applied specifically to control these pests has increased.

Table 1: Insect Species Attacking Mississippi Cotton

Table 2: Ten-year summary of the top three most damaging cotton insects in Mississippi

Table 3: Some Non-insecticidal Components of Cotton IPM

Table 4: Insecticides recommended for use as foliar sprays in Mississippi cotton.

OP = organophosphate; C = Carbamate; CN = Chloro-nicotinyl; IGR = insect growth regulator; SPN = spinosyn; OX = oxadiazine; OC = organochlorine; P = pyrethroid

Table 5: Comparison of number of insecticide treatments and percent boll damage on Bt and non-Bt cotton in Mississippi, 6-year summary.

Figure 1. Estimated average cost per acre of controlling cotton insects in Mississippi (from nnual Cotton Insect Losses Estimates). These estimates include cost of insecticides, application costs, scouting fees, eradication program fees, and licensing fees for use of Bt cotton. The sharp increase in costs beginning in 1992 is due primarily to the development of high levels of insecticide resistance in tobacco budworm and other cotton pests. Since 1996, a number of new tools have been introduced that provide improved control of pests that are resistant to older insecticides. However, because these new tools are higher in cost and more target specific, their availability has had relatively little effect on the cost of insect control.

Figure 2. Average number of foliar insecticide treatments applied to Mississippi cotton fields, 1988-2000. The decline in number of spray applications is due to progress of the Boll Weevil Eradication Program and to widespread adoption of transgenic Bt-cotton. Treatments of ULV malathion applied as part of the Boll Weevil Eradication Program are not included in these estimates.

Cotton Insect Losses in Mississippi 2000

Table 16a. Mississippi Delta

Pest	acres infested	acres treated	# insect appls	Cost of 1 applic	cost/ acre	%red	Bales lost
Boll weevil	0	0	0.000	N/A	$0.00	0.000	0
Bollworm/budworm	812,000	410,000	1.161	$13.20	$15.33	1.900	32,142
Pink Bollworm	0	0	0.000	N/A	$0.00	0.000	0
Cotton Fleahopper	28,000	0	0.000	N/A	$0.00	0.002	29
Lygus	812,000	730,000	1.259	$7.20	$9.06	0.500	8,458
Cotton Leafperforator	0	0	0.000	N/A	$0.00	0.000	0
Spider Mites	160,000	55,000	0.088	$10.80	$0.95	0.059	1,000
Thrips, early season	812,000	510,000	0.817	$5.40	$4.41	0.700	11,842
Beet Armyworm	390,000	83,000	0.102	$11.70	$1.20	0.096	1,625
Fall Armyworm	580,000	120,000	0.148	$11.80	$1.74	0.429	7,250
European Corn Borer	20,000	0	0.000	N/A	$0.00	0.000	0
Stink Bugs	420,000	5,100	0.006	$7.20	$0.05	0.207	3,500
Grasshoppers	8,200	0	0.000	N/A	$0.00	0.001	17
Salt-marsh Caterpillars	129,000	17,000	0.021	$9.20	$0.19	0.016	269
Aphids	812,000	490,000	0.724	$6.80	$4.92	0.400	6,767
Bandedwinged Whitefly	510,000	85,000	0.136	$8.70	$1.18	0.031	531
Silverleaf Whitefly	0	0	0.000	N/A	$0.00	0.000	0
Soybean Loopers	140,000	37,000	0.046	$11.70	$0.53	0.017	292
Cabbage Loopers	0	0	0.000	N/A	$0.00	0.000	0
Western Flower Thrips	0	0	0.000	N/A	$0.00	0.000	0
Cutworms	812,000	110,000	0.135	$6.60	$0.89	0.080	1,353
Percent Lost	4.44		Est. yield/acre	680			Cost/ Acre
						Foliar insecticide	$40.46
Total Acres	812,000		Spray applications	4.643		At planting	$9.66
						Bt use fees	$21.20
			Cost + loss	$103,214,750		Eradication	$22.00
Total Bales lost	75,075					Scouting	$7.16
Bales lost in dollars	$21,621,480		Cost + loss/acre	$127.11		Total	$100.48

Table 16a. Mississippi Hills

Pest	acres infested	acres treated	# insect appls	Cost of 1 applic	cost/ acre	%red	Bales lost
Boll weevil	0	0	0.000	N/A	$0.00	0.000	0
Bollworm/budworm	475,000	105,000	0.354	$13.20	$4.67	2.800	27,708
Pink Bollworm	0	0	0.000	N/A	$0.00	0.000	0
Cotton Fleahopper	10,800	0	0.000	N/A	$0.00	0.000	0
Lygus	475,000	140,000	0.354	$5.55	$1.96	0.100	990
Cotton Leafperforator	0	0	0.000	N/A	$0.00	0.000	0
Spider Mites	320,000	19,000	0.052	$11.30	$0.59	0.067	667
Thrips, early season	475,000	142,000	0.359	$4.60	$1.65	0.500	4,948
Beet Armyworm	140,000	13,000	0.027	$11.90	$0.33	0.029	292
Fall Armyworm	187,000	37,000	0.078	$13.25	$1.03	0.472	4,675
European Corn Borer	0	0	0.000	N/A	$0.00	0.000	0
Stink Bugs	350,000	33,000	0.069	$7.40	$0.51	0.221	2,188
Grasshoppers	43,000	10,000	0.021	$7.60	$0.16	0.018	179
Salt-marsh Caterpillars	80,000	2,000	0.004	$8.30	$0.03	0.017	167
Aphids	475,000	41,000	0.095	$6.50	$0.62	0.210	2,078
Bandedwinged Whitefly	220,000	21,500	0.059	$9.95	$0.59	0.093	917
Silverleaf Whitefly	1,000	300	0.001	$19.50	$0.01	0.011	104
Soybean Loopers	75,000	10,000	0.021	$12.30	$0.26	0.047	469
Cabbage Loopers	0	0	0.000	N/A	$0.00	0.000	0
Western Flower Thrips	0	0	0.000	N/A	$0.00	0.000	0
Cutworms	475,000	42,000	0.088	$6.90	$0.61	0.100	990
Percent Lost	4.69		Est. yield/acre	630			Cost/ Acre
						Foliar insecticide	$13.02
Total Acres	475,000		Spray applications	1.582		At planting	$8.09
						Bt use fees	$24.40
			Cost + loss	$48,969,103		Eradication	$23.40
Total Bales lost	46,370					Scouting	$6.07
Bales lost in dollars	$13,354,500		Cost + loss/acre	$103.09		Total	$74.98

Insecticides recommended for use in Mississippi cotton and the primary pests for which they are recommended are listed in Table 4. Tables 6A-6D summarize the relative use of these insecticides during the past four growing seasons, 1998 through 2001. Examination of these tables shows that acephate, dicrotophos, and the pyrethroids (collectively) were the most commonly used insecticides. The use and significance of each of the insecticides recommended for use in Mississippi cotton is discussed below.

Foliar Applied Insecticides:

Acephate (Orthene): For the past several years acephate has been the most commonly used individual foliar insecticide in Mississippi cotton. In 2001 Mississippi growers applied approximately 1.4 applications of acephate per field, which constituted one-third of all foliar sprays.

The most important use of acephate is for control of tarnished plant bug. Acephate belongs to a different sub-class of chemistry than most other organophosphates used on cotton, and it is one of the few 'older' insecticides to which plant bugs have not developed high levels of resistance. Acephate is used to control plant bugs throughout the growing season. Use rates in the range of 0.25 to 0.5 lbs. Ai./acre are usually effective during early season, but rates of at least 0.5 lbs ai/acre are required during mid to late season. Successful control of heavy, mid to late season plant bug infestations requires repeated applications applied approximately 5 days apart.

In addition to being used as an at-planting seed treatment and as an in-furrow treatment for thrips control, acephate is also commonly used as a foliar treatment to control thrips on seedling cotton. Rates of 0.2 to 0.25 lbs ai/acre are effective against all species of thrips, except the western flower thrips. Acephate is also recommended for control of cutworms, stink bugs, and whiteflies. Acephate is especially useful as a tank mix partner with pyrethroid insecticides to control mixed populations of bollworms and plant bugs.

Dicrotophos (Bidrin): Dicrotophos is one of the most frequently used cotton insecticides. In 2001, Mississippi cotton received an average of 0.53 applications per field, which represented 12.9% of all foliar insecticide treatments. The relative importance of dicrotophos has increased in recent years, because plant bugs and stink bugs are becoming more important in post-eradication/Bt cotton systems.

Tarnished plant bugs are the primary target of most dicrotophos applications. However, in the Delta Region, the performance of dicrotophos is somewhat erratic because of resistance. Still, dicrotophos remains one of the more important treatments for tarnished plant bug. Rates of 0.25 to 0.33 lbs ai/acre may provide effective control during early season, especially in the Hill Region, but the 0.5 lb ai/acre rate is required during mid to late season. Multiple applications applied approximately 5 days apart are required to control heavy mid to late season plant bug infestations. Dicrotophos is also quite effective against stink bugs and is a good choice for control of mixed populations of plant bugs and stink bugs during mid to late season.

Dicrophos is one of only three products recommended for control of cotton aphids. A single, properly timed application will usually provide adequate control of aphid infestations, but overall efficacy is somewhat less than that of products like carbofuran or thiamethoxam. Dicrotophos is a cost-effective treatment for control of mixed infestations of plant bugs and aphids. It is also recommended for control of thrips on seedling cotton, and is useful against a number of occasional pests.

Dimethoate: Dimethoate is an organophosphate insecticide that has declined in use, primarily because of resistance in aphids and tarnished plant bugs. Currently, it is only recommended for control of thrips on seedling cotton at a rate of 0.2 lbs ai/acre. It is not commonly used.

Methyl Parathion: As the treatment of choice against boll weevils, this organophosphate insecticide was once the most commonly used treatment in Mississippi cotton. However its use has plummeted since the initiation of boll weevil eradication efforts. Currently it is recommended only for control of stink bugs, but it receives very little use. However, methyl parathion is one of the most cost-effective treatments for stink bugs, and it continues to be important for this reason.

Methamidophos (Monitor): Methamidophos is a relatively expensive organophosphate insecticide, and because of this, it is rarely used. It is recommended primarily for control of whiteflies, which are occasional pests. It is also effective against thrips and plant bugs. The 0.2 lb. Ai/acre rate is effective against thrips, but the 0.5 lb. Ai./acre rate is required to best control plant bugs and whiteflies.

Profenophos (Curacron): At one time profenophos was widely used for control of tobacco budworms and tarnished plant bugs, as well as other pests. However, its use has declined greatly in recent years due to resistance in tobacco budworm and plant bug populations, as well as to wide spread planting of Bt cotton and availability of new, more effective caterpillar materials.

In 2001 Mississippi cotton fields received only 0.08 applications of profenophos, which represented only 2% of all foliar insecticide sprays.

Profenofos is still recommended for control of budworm/bollworm and plant bugs, but its use is limited due to the factors previously mentioned. It is also labeled and recommended for control of spider mites and fall armyworms, but it is generally less effective than other labeled products against both pests. Currently the key value of profenophos is that it is an economical choice for use against mixed populations of bollworms and plant bugs, or against mixed populations of bollworm/budworm and a building spider mite infestation. Use rates range from 0.25 lbs ai/acre (as an ovicide for control of bollworm/budworm eggs) to 1.0 lbs ai/acre (larvicide rate).

Propargite (Comite): Propargite, which is a specific miticide, is rarely used in Mississippi, because of cost and because spider mite outbreaks are uncommon. This organophosphate miticide is also difficult to obtain, because it is not commonly stocked by distributors. However, because it is one of the more effective products for use against mites, it would become extremely important in the event of a severe mite outbreak.

Oxamyl (Vydate): Oxamyl is a carbamate insecticide. Its overall use has declined in recent years because the boll weevil eradication program has eliminated one of two pests for which it was used. Currently oxamyl is primarily used for control of tarnished plant bugs at a recommended rate of 0.25 to 0.33 lbs. Ai./acre. In 2001 Mississippi cotton received an average of 0.14 applications of oxamyl, which represented 3.4% of all foliar sprays. Because it belongs to a different class of chemistry than other plant bug materials, Oxamyl plays an important role in plant bug resistance management.

Methomyl (Lannate): Methomyl is a carbamate insecticide that was commonly used as an ovicide and as a larvicide against bollworm/tobacco budworm. However, this product is rarely used today because of widespread planting of Bt cotton and availability of more effective caterpillar treatments. Currently methomyl is recommended as an ovicide (0.25 lbs ai/acre) to control bollworm and tobacco budworm eggs. It is recommended at 0.45 lbs ai/acre for control of larvae of bollworm, tobacco budworm, and fall armyworm. When applied at this rate, methomyl has a tendency to cause mild phytotoxicity (reddening of leaves), and this is another factor that limits its use.

Thiodicarb (Larvin): Thiodicarb is a carbamate insecticide that was commonly used as an ovicide (at 0.25 lbs ai/acre) and as a larvicide (at 0.6 to 0.9 lbs ai/acre) against bollworm/tobacco budworm and other caterpillar pests. This product is rarely used today because of widespread planting of Bt cotton and availability of newer caterpillar treatments. Currently thiodicarb is recommended as an ovicide to control bollworm/budworm eggs in non-Bt cotton. It is also recommended for control of bollworm/budworm larvae and for control of loopers and armyworms. Thiodicarb continues to be one of the most effective treatments for use against larger, 'escaped', bollworm/budworm larvae. Thiodicarb is not 'rain fast' and requires several rain free/irrigation free days for maximum efficacy. This lack of rain fastness is another factor that limits its use.

Imidacloprid (Provado): Imidacloprid is a chloro-nicotinyl insecticide that has been available for several years. It is recommended for control of cotton aphids and tarnished plant bugs at a rate of 0.047 lbs ai/acre. However, imidacloprid receives little use in Mississippi cotton because of its relatively high price. In 2001 Mississippi fields received approximately 0.09 applications of imidacloprid per field, which represented 2.2% of all foliar sprays.

Thiamethoxam (Centric): Thiamethoxam is a chloro-nicotinyl insecticide that was first labeled in 2001. At the recommended use rate of 0.047 lbs ai/acre, it is effective against cotton aphids and tarnished plant bugs, as well as whiteflies. Mississippi cotton fields received approximately 0.14 applications of thiamethoxam in 2001, which constituted approximately 3.4% of all foliar sprays. Because it provides good control of aphids and plant bugs and is reasonably priced, the relative use and importance of thiamethoxam will likely increase.

Tebufenozide (Confirm): Tebufenozide is an 'insect growth regulator' that is recommended for control of beet armyworms. It is very effective against this pest but has little activity against other caterpillar pests. Consequently, it is rarely used.

Methoxyfenozide (Intrepid): Methoxyfenozide is an 'insect growth regulator' that is recommended for control of beet armyworms, fall armyworms, and loopers. At the recommended use rate of 0.06 to 0.1 lbs ai/acre it is a very effective, economical treatment for these pests. Because of its wider spectrum of activity, methoxyfenozide has displaced tebufenozide in cotton. Methoxyfenozide also has activity against bollworm/tobacco budworm, but the rates required to control these pests are cost prohibitive. Although this product is rarely used in most years, it is a very important component of the cotton insecticide arsenal because it provides cost-effective control of several important occasional pests.

Pyriproxyfen (Knack): Pyriproxyfen is an 'insect growth regulator' that is recommended for control of silverleaf whiteflies at a rate of 0.054 to 0.067 lbs ai/acre. It is a very expensive treatment that is rarely used because silverleaf whitefly infestations are uncommon in Mississippi. Still, this pest does occasionally occur in the state, and pyriproxyfen would become a very important product in the event of an outbreak of silverleaf whiteflies.

Spinosad (Tracer): Spinosad is a relatively new insecticide that is used solely to control caterpillar pests. It belongs to the class of chemistry known as spinosyns. Use rates range from 0.067 to 0.089 lbs ai/acre (the 0.045 lbs ai/acre rate is not recommended, except as a tank mix partner). Spinosad provides good control of tobacco budworms, as well as most other caterpillar pests, and this makes it an important tool in the production of non-Bt cotton. It is rarely used in Bt cotton. In 2001, Mississippi cotton fields received approximately 0.21 applications of Tracer, but only 20% of the acres were planted to non-Bt varieties. In 2000 Mississippi fields received an average of 0.58 applications of Tracer. Tracer is relatively benign to most beneficial insects.

Indoxacarb (Steward): Indoxacarb was first labeled for use in cotton in 2001. It belongs to the oxadiazine class of insecticides. At the recommended rate of 0.09 to 0.11 lbs ai/acre it is effective against most caterpillar pests. Because it is effective against tobacco budworms, the primary use niche for indoxacarb is in non-Bt cotton. In 2001 Mississippi cotton fields received approximately 0.13 treatments of indoxacarb, which represented 3% of all foliar sprays. However, overall use of this product may well increase, especially if the percentage use of Bt cotton declines following successful eradication of the boll weevil. Indoxacarb also has activity against tarnished plant bug. Although it is not recommended for use against plant bugs as a primary target pest, this is an important advantage when growers need to control mixed infestations of caterpillars and tarnished plant bugs.

Dicofol (Kelthane): Dicofol is an organochlorine miticide. It is rarely used in Mississippi cotton, primarily because mite outbreaks are relatively uncommon. However, in the event of severe spider mite outbreaks it would become more important.

Pyrethroids: The pyrethroids currently recommended for use in Mississippi cotton are: bifenthrin (Capture), cyfluthrin (Baythroid), cyhalothrin (Karate-Z), cypermethrin, (Ammo), deltamethrin (Decis), esfenvalerate (Asana XL), fenpropathrin (Danitol), tralomethrin (Scout X-Tra), and zetamethrin (Fury). These are discussed collectively because of their broad similarities. Collectively, the pyrethroids are one of the most important, most commonly used insecticides. In 2001 Mississippi cotton fields received an average of 0.98 applications of pyrethroids, which represented 25.8% of all foliar insecticide sprays.

Pyrethroids are broad spectrum insecticides, providing control of a number of important pests. However, their overall utility has eroded in recent years due to development of high levels of pyrethroid resistance in cotton aphids, tobacco budworms, and tarnished plant bugs (plant bug resistance to pyrethroids is primarily in the Delta Region).

Currently the most important use of pyrethroids is for control of bollworms in Bt cotton. Pyrethroids are highly effective against bollworms and are more economical than the available alternatives. Pyrethroids are no longer recommended for control of tobacco budworms, because of high levels of resistance, but they continue to be useful in non-Bt cotton, against populations that are known to be primarily bollworms. Some pyrethroids are useful in the control of fall armyworms.

Pyrethroids are also recommended for control of cutworms and are often applied at planting in fields that have a high potential for experiencing cutworm problems. Because pyrethroids are effective against cutworms at very low rates, they are more economical than the alternatives. The recent increase in the utilization of herbicide tolerant cotton and the resulting increase in reduced till/no-till planting has resulted in increased potential for cutworm infestations. Pyrethroids are also recommended for control of stink bugs, a pest that is increasing in importance due to boll weevil eradication and wide spread planting of Bt cotton. Pyrethroids are an especially cost-effective treatment for mixed infestations of bollworms and stink bugs, which can occur in Bt cotton during mid to late season.

Bifenthrin (Capture) is a somewhat unique pyrethroid that also has activity against spider mites and is recommended for control of mites. In past years bifenthrin was also recommended for control of cotton aphids, but development of pyrethroid resistance in aphids has nullified this use. Fenpropathrin (Danitol) is recommended primarily in a tank mix with acephate for control of silverleaf whiteflies, which currently is a very minor use in Mississippi. Fenpropathrin also has activity against spider mites.

Soil Applied Insecticides:

Soil applied insecticides are applied at planting, primarily for control of thrips. These treatments may be applied as seed treatments, or as in-furrow granules or in-furrow sprays.

Aldicarb (Temik): Aldicarb, which is a carbamate, is the most commonly used soil applied insecticide. This is because of its excellent, long-lasting activity against thrips and because, when used at adequate rates, it provides good suppression of nematodes. In 2001, approximately 59% of Mississippi cotton fields were treated with aldicarb. Recommended use rates range from 3.5 to 5 lbs. Ai/acre. Aldicarb also provides early season suppression of plant bugs and cotton aphids, but it does not control cutworms.

Acephate (Orthene): When applied as a seed treatment, acephate (organophosphate) will provide thrips control in seedling cotton for 7 to 10 days after emergence. However, acephate is also recommended as a liquid in-furrow spray or as the granular formulation know as Payload at a rate of 1.0 lbs ai/acre, and this rate will provide longer thrips control, as well as suppression of plant bugs and cutworms.

Imidacloprid (Gaucho): Imidacloprid is a chloro-nicotinyl insecticide that is offered as a seed treatment. It provides effective control of thrips on seedling cotton and was used on approximately 9% of Mississippi cotton fields in 2001.

Thiamethoxam (Adage): Thiamethoxam (chloro-nicotinyl) is sold as a seed treatment known as Adage for control of thrips on seedling cotton. This new product provides effective control of thrips for two to three weeks following emergence. It will also control aphids on seedling cotton. Use of thiamethoxam is likely to increase in future years, but will be limited somewhat by the lack of nematode control.

Table 6A: Use of individual foliar applied insecticides on cotton in Mississippi, 2001¹.

Compiled from a survey of 120 Mississippi Cotton Fields (69 Bt fields and 51 non-Bt fields) which received a total of 496 foliar insecticide treatments.

¹Does not include foliar applications of ULV malathion applied as part of the boll weevil eradication program.

Table 6B: Use of individual foliar applied insecticides on cotton in Mississippi, 2000¹.

Compiled from a survey of 59 Mississippi Cotton Fields (34 Bt fields and 25 non-Bt fields) which received a total of 183 foliar insecticide treatments.

¹Does not include foliar applications of ULV malathion applied as part of the boll weevil eradication program.

Table 6C: Use of individual foliar applied insecticides on cotton in Mississippi, 1999¹.

Compiled from a survey of 93 Mississippi Cotton Fields (55 Bt fields and 38 non-Bt fields) which received a total of 317 foliar insecticide treatments.

¹Does not include foliar applications of ULV malathion applied as part of the boll weevil eradication program.

Table 6D: Use of individual foliar applied insecticides on cotton in Mississippi, 1998¹.

Compiled from a survey of 133 Mississippi Cotton Fields (78 Bt fields and 55 non-Bt fields) which received a total of 848 foliar insecticide treatments.

¹Does not include foliar applications of ULV malathion applied as part of the boll weevil eradication program.

BOLL WEEVIL

Historically, the boll weevil was the most important insect pest of Mississippi cotton. Boll weevil was considered a key pest of cotton, because the early season treatments that were necessary to control boll weevil destroyed beneficial insects and thus "flared" secondary pests, such as tobacco budworms and aphids.

As of the end of the 2001 growing season, statewide eradication efforts have reduced boll weevil numbers to extremely low levels, and it appears that complete eradication will be achieved within the next two years. Mississippi cotton growers no longer spray for boll weevils themselves, and only 32% of Mississippi's cotton acreage was treated by the Boll Weevil Eradication Program (BWEP) in 2001. Fifty-one percent of Mississippi fields remained weevil free for the entire season, and no yield loss was attributed to boll weevils in 2001. Therefore, the primary concern for Mississippi cotton with respect to the boll weevil is to complete the BWEP and to successfully maintain eradication, once it is achieved. The Hill Region of Mississippi passed a 10-year eradication maintenance referendum in 2001 and the remaining two regions of the state will vote on maintenance programs during the next two years.

A successful maintenance program will require the continuation of a vigorous pheromone trapping program on all cotton in the state. This is necessary so that any re-infestations of boll weevils can be promptly detected and eliminated before they have a chance to spread. Successful eradication maintenance will also require continued education of growers and scouts, so that they will be able to recognize and promptly report the presence of boll weevils and/or boll weevil damage in their fields. Successful eradication maintenance also requires continued, ready access to insecticides that are effective against boll weevils and can be used to eliminate any re-infestations that do occur. Because of logistical, environmental, and cost considerations, Malathion ULV has been the primary insecticide used in the BWEP, but a number of other insecticides are also effective against boll weevils.

The damage done by the pest: Weevils puncture squares and bolls with their snouts to feed and to lay eggs. If a weevil puncture is topped with a whitish or brown bump or "wart", it is an indication that the female has laid an egg in the hole and sealed the puncture to protect the egg. This gluey substance is white on newly sealed egg punctures, but browns with age. Some weevil punctures will not have this sealer, particularly if the insect merely feeds. Normally, the weevil, prefers squares and makes only one egg puncture per square, but it will select young bolls in many cases. Weevil damage will range from one or two locks per boll to complete boll loss since many punctured squares or young bolls will drop off after the pest drills the hole.

Life cycle: Total time from egg to adult ranges from 16 to 25 days; egg - two to three days; larva - five to eight days; pupa - three to five days; newly emerged adult ("callow" adult) - one day; feeding adult - five to eight days before egg laying. Adult females lay an average of 30 eggs each day for approximately 10 days. Each generation normally multiplies tenfold. In a typical field boll weevils numbers will increase at a rate of about two and one-half times each week - about the same rate of increase as the squares in the field.

Boll weevils spend the winter in a semi-dormant state (reproductive diapause) in hardwood ground cover, such as patches of woods. During mild winters, they also can survive in grass or other cover. Usually four generations of weevils occur during the season. When daytime temperatures begin to rise above 70 degrees weevils begin emerging. Emergence may continue from before cotton is big enough to support the pests until July, peaking normally in May and June.

While there are not always clear-cut steps in the emergence of over-wintered weevils, the first adult in-field generation can begin emerging about a week after the first white bloom, with others following at about three-week intervals. Climate and weevil food supply can greatly influence peaks in weevil populations.

Critical timing of control measures: Treatment for suppression of overwintering boll weevils is determined using pheromone traps. If trap captures the week prior to squaring exceeds four weevils per trap per week, a suppression spray may be needed, and a second treatment may be required if populations are high. These 'pin-head square sprays' are highly effective in eliminating a large portion of the overwintered generation of boll weevils before they have an opportunity to reproduce. After cotton begins to square, applications of insecticides to control the boll weevil will normally be applied when square damage levels reach specified treatment thresholds. Successful control requires the application of a series of three to six treatments applied on a three to four day schedule. This spray schedule is necessary because immature stages of the boll weevil are inside squares and bolls where they are protected from exposure to insecticides. The objective is to control newly emerged adult boll weevils before they have the opportunity to reproduce.

Yield losses and prevalence: In the absence of effective control efforts boll weevils have the ability to completely destroy a cotton crop. Historically, 100% of Mississippi's cotton fields were infested by boll weevils and growers applied multiple, close interval insecticide treatments to keep boll weevil populations in check. Despite this heavy insecticide use, yield losses were still significant. Before the BWEP was initiated in 1997 the estimated annual yield loss attributed to boll weevils ranged from 0.2% to 6.5%. Yield losses were historically higher following milder winters, which allowed higher survival of overwintering weevils. Yield losses also were historically higher in the Hill region of the state than in the Delta region and often exceeded 5% in the Hills. Beginning in 2000, and continuing in 2001, the eradication effort had reduced boll weevil populations to such low levels that no yield loss was attributed to this pest.

Chemical Control Information:

Control Alternatives:
Pheromone traps and the Boll Weevil Eradication Program are the primary alternatives for controlling the boll weevil. Originally started in North Carolina and Virginia in 1978, the Boll Weevil Eradication Program (BWEP) program has since been implemented by most of the other cotton producing states in the southeastern United States. The implementation of BWEP is expected over the rest of the state in the next eight years. The primary components of BWEP are timely applications of malathion and intensive use of boll weevil pheromone traps. It is a very intensive program that requires close monitoring of boll weevil populations in coordination with producers.

Cultural Control Practices: Early-maturing varieties may escape damage by late season generations when boll weevil populations are highest.

Biological Controls: There are few effective parasitoids or predators of boll weevils in the Mid-South. Fire ants are known to prey on developing weevils in fallen squares, but this predation does not provide effective biological control.

COTTON BOLLWORM and TOBACCO BUDWORM

The bollworm and tobacco budworm species comprise what is commonly referred to as the Heliothine complex. Both species belong to the Noctuidae family of insects and attack cotton in a similar fashion. In Arkansas, bollworm and tobacco budworm populations vary greatly from south to north. The overall population levels of the Heliothine complex are higher in south Arkansas. Both species occur as pests of cotton each year. Of the two species, the bollworm is a more frequent problem whereas the tobacco budworm is more difficult for producers to control. Tobacco budworms are resistant to many insecticides especially those in the pyrethroid class of insecticides. Over the past 10 years, the tobacco budworm has become a more difficult insect to control.

The damage done by the pests: The most obvious damage is feeding on squares and bolls, but bollworms and budworms can also reduce yields through secondary damage. Feeding damage often provides entry for disease organisms, which can lead to boll rot. This usually occurs in irrigated cotton, but it can occur in wet periods after rainfall.

Life cycle: Egg - three to five days; larva - 12 to 15 days spent feeding on cotton; pupa - 12 to 15 days, resting in top two to four inches of the soil; adult - moths emerge from pupae and begin laying eggs in 3 to 12 days. The development of one complete generation thus may require from 27 to 35 days. Female bollworm moths can lay from 250 to 1,500 eggs. In a normal season, there usually are about five generations, but some of these are spent on plants other than cotton. Normally, only two or three generations inflict important damage on cotton.

These worms overwinter in the soil, in the pupa stage, after going through a preparation phase. Moth migration is common and moths may move many miles. Expect the first generation in early spring. At that time, the pests develop on legume crops, such as crimson clover of alfalfa. The second generation of bollworms prefer corn; when found in corn this insect is called the corn earworm. Third generation worms generally are the first infestation for cotton, but insects also will infest corn or grain sorghum if these crops are present. If corn or milo is close by, the third generation may leave and migrate into cotton. Also, roadside plants such as evening primrose attract bollworms.

Light intensity, rather than the time of day, triggers bollworm and budworm behavior. On an average day, light intensity of 800 footcandles, known to affect moth feeding, is reached at 4 to 5 p.m. Moths feed on nectar from flowers and the nectary glands of cotton. Aphid honeydew also is an attractive food, as well as water droplets. By 7 p.m., if the light intensity is around 28 footcandles, moths are triggered into laying eggs, which may continue until 9 to 10 p.m. Some eggs are laid in blooms so newly emerged larva may feed inside the bloom. Blossoms may fold over the pests, so insecticide coverage failure can occur. Newly hatched larvae may feed on leaves the first day before attacking squares andbolls.

Critical timing of control measures: Before bloom, treatment is recommended if the number of larvae reaches or exceeds 8 per 100 plants. From first bloom through cutout the threshold is 4 larvae per 100 plants but increases to 8 per 100 plants after cutout. On non-Bt cotton it is extremely important to target applications against larvae that are no longer than 1/4 inches down to egg hatch. Thresholds for Bt cotton are similar, except that only larvae greater than 1/8 of an inch in length are included in the count (smaller larvae may be controlled by the Bt toxin, but larvae that have attained this 1/8 inch size are likely to survive on Bt).

Yield Losses and Prevalence: Historically, the bollworm/tobacco budworm complex has been one of the most damaging and most costly insect pests of Mississippi cotton. Tobacco budworm has the potential to totally destroy a field, and this occurred in a large number of fields in Mississippi's Hill Region in 1995. All Mississippi fields are infested by this pest complex, however infestation levels and damage have declined somewhat in recent years due to wide spread adoption of transgenic Bt cotton. Still, if the costs of the "technology use fee" are considered, the cost of controlling these pests remains high. Statewide yield losses attributed to bollworm/budworm have ranged from 1.9 to 8.0% during the past 10 years, but a 23% yield loss was reported for the Hill Region in 1995. Costs of bollworm/budworm control reached approximately $82 per acre in the Hill Region that year. Statewide control costs for this pest complex have ranged from $34 to $57 per acre during recent years.

Chemical Control Information - Ovicides

Chemical Control Information - Larvae and Adults

Control Alternatives: Emamectin benzoate (Denim), which is currently under developed and has been used under Section 18 Emergency Exemptions, is effective against bollworm and tobacco budworm, as well as most other caterpillar pests. Transgenic Bt cotton was planted on approximately 80% of Mississippi's cotton acreage in 2001.

Cultural Control Practices: Transgenic B.t. cotton varieties currently provide 100% control of tobacco budworms and approximately 60 to 70% control of bollworms. Early maturing varieties of non-Bt cotton may escape damage from the last, and heaviest, generations of budworm and bollworm. Varieties exhibiting the 'high-glanding trait' possess some resistance to budworm and bollworm. Smooth leaf varieties are less attractive to ovipositing moths than are varieties with more hairy leaves. Fields planted using no-till methods often benefit from enhanced biological control of bollworm/budworm due to coincidental conservation of fire ants, which are important predators of bollworm/budworm eggs and larvae. Fields planted using conventional tillage methods are usually tilled in the fall or early spring, before bollworm/budworm pupae overwintering in the field have a chance to emerge. This tillage causes high mortality levels in that portion of the bollworm/budworm population overwintering in cotton fields.

Biological Controls: Naturally occurring biological control is the most important method of controlling tobacco budworm. Despite its damaging and costly history as a pest of cotton, tobacco budworm is most appropriately considered a secondary pest (bollworm is more appropriately considered a major pest, because of the movement of large numbers from corn). Tobacco budworm has a large number of predators and parasitiods, which will often prevent it from reaching damaging levels, unless they are destroyed by early season insectide treatments applied to control other pests. Most of these will also attack bollworm and aid in suppressing bollworm populations as well. Consequently, monitoring beneficial insect populations and considering their presence and abundance in treament decisions can aid greatly in management of bollworm and budworm.

THRIPS

Thrips are a common (i.e., yearly) problem for most cotton producers in the Mid-South. Thrips infest cotton in the young seedling stage and severe thrips damage can stunt growth and reduce yield potential. As a result, most cotton is treated with an in-furrow insecticide to prevent the development of damaging populations and consequently thrips are rarely a devastating problem. cotton.

The damage done by the pest: Thrips have punch and suck or piercing sucking mouthparts, which allow them to punch a hole in a leaf cell, insert their maxillary stylets, and suck up the cellular fluids. When it occurs on leaves and other plant parts that have already expanded, this type of injury causes little or no significant harm to the plant. However, when such injury occurs within the terminal bud, on tiny developing leaves and fruiting structures, the effect can be quite different.

When thrips feed on the young undeveloped leaves within the terminal bud, the resulting damage is magnified as those leaves develop and expand. This is because the damaged tissue fails to develop properly, while undamaged tissue continues to grow. After prolonged feeding or feeding by high numbers of thrips, seedlings have a ragged appearance, with visible silvery feeding sites on cotyledons and terminal leaf tissue. Over time these silver areas will become brown in color. Heavily injured leaves usually have a crinkled, tattered appearance and often curl upward at the margins. Seedlings exhibiting this type of injury are often described as "possum eared cotton". Heavy thrips populations can stunt growth, cause death of the terminal bud (resulting in "crazy cotton"), delay fruiting and reduce stand. Thrips damage often is magnified by cool weather or drought, which can slow plant growth and/or lengthen thrips' developmental time and increase the probability of seedling damage. Seedlings that emerge under warm, favorable growing conditions are much less susceptible to thrips injury than are those that emerge under conditions conducive to slow seedling development.

Life cycle: Egg - four days; larva - six days, molting twice; pupa - four days; egg to adult - 14 days average. These pests overwinter in the pupa stage in plant trash. They begin reproducing in early spring in non-cotton host plants, such as grains, early blooming weeds, and legumes. Once the early host plants toughen, thrips move quickly into cotton fields. In many areas of the Cotton Belt, thrips migrate into cotton about the time wheat is cut. When the pests migrate, late-planted cotton is one of their chief targets since the crop is tender and offers easy feeding.

Critical timing of control measures: Of the various methods used to control thrips, most must be applied on a preventative basis, before there is any evidence that a potentially yield limiting infestation of thrips has occurred. Thrips are the only cotton insect pests for which such preventative treatments are recommended. However, because of the nature of thrips migration into cotton fields and the nature of the cotton plant=s susceptibility to thrips, these preventative, at planting type treatments generally are recommended over the "no at planting treatment and spray as needed" approach in most cases. This is especially true for fields planted under cool or adverse growing conditions, because slow plant growth results in a wider window of susceptibility to thrips injury. Fields planted during late season, under warm ideal growing conditions are less likely to benefit from in-furrow, systemic insecticides.

Regardless of whether or not a field is treated with a soil or seed applied insecticide at planting, all fields should be scouted carefully for thrips until plants reach the four-leaf stage. Fields should be scouted at least every five days, but a three to four day schedule is even more effective. There are a number situations that can cause soil applied treatments to fail, and frequent scouting, combined with prompt application of supplemental foliar sprays can prevent yield limiting injury.

Yield losses and Prevalence: Thrips infest every acre of Mississippi cotton every year, but the degree of infestation varies considerably, depending on the season. The ultimate impact of thrips injury on yield is highly variable. Cotton that is planted under good growing conditions can withstand relatively heavy infestations without suffering yield loss. However severe thrips injury can result in substantial yield reductions. In 14 trials conducted in Mississippi between 1994 and 2000 the yield losses in the untreated check compared to the most effective treatment in the trial ranged from 10 to 271 lbs. of lint/acre. The average yield increase for the standard treatment (aldicarb) was 114 lbs of lint. Average yield losses attributed to thrips range from 0.1 to 0.6%, but these losses would be much higher in the absence of effective treatments.

Chemical Control Information:

Control Alternatives: A number of other insecticides will control thrips when applied as foliar treatments, but are not recommended because of economic or resistance management concerns. Also, foliar treatments are generally less effective in preventing yield loss than 'at-planting' treatments. Thiamethoxam (Adage) is very effective as a seed treatment for control of thrips. Thiamethoxam has recently been added to the Mississippi Cotton Insect Control Guide.

Cultural Control Practices: Fields planted during late season, into warm, moist soil with good growing conditions are less likely to benefit from in-furrow systemic insecticides than are fields planted under cool, adverse growing conditions. Some cotton varieties are more tolerant than others to thrips injury.

Biological Controls: Thrips are attacked by a number of predators, including the insidious flower bug, but their importance in the population dynamics of thrips on seedling cotton is unknown.

PLANT BUGS

Tarnished Plant Bug (TPB) is an important pest of cotton throughout Mississippi. However, it is relatively more important in the Delta Region of the state than in the Hills. TPB is considered a "key" pest of cotton because it often reaches treatable levels during the early portion of the season and insecticides applied to control these early plant bug infestations often flare populations of secondary pests, such as aphids or tobacco budworms. Before boll weevil eradication the importance of TPB as a key pest of cotton was overshadowed by the boll weevil. Due to the success of the boll weevil eradication effort and the wide spread adoption of Bt-cotton, the importance of TPB has increased in recent years. Not only have boll weevils and budworm/bollworm declined in importance, but the reduction in sprays applied to control these pests results in less coincidental control of TPB. As a result, the number of sprays required specifically to control TPB has increased in recent years, especially in the Delta.

The damage done by the pest: All plant bugs have piercing mouthparts used to suck plant juices. Pinhead squares are primary targets. Soon after damage, the small squares turn brown and shed. Pre-squaring cotton is not safe though, since these insects attack growing portions of the plants and inflict serious damage even before square formation. Plant bugs, in this case, damage the stems and the young, tender terminals of the cotton plant. This injury can be serious enough to cause the plants to shift into exaggerated growth, with cotton branches becoming long and whip-like. In many cases, the cotton never really recovers. Damage symptoms sometimes cause "crazy cotton" where plants are severely distorted and stay in a pattern of fruitless growth for several weeks.

Severe infestations often develop quickly because these pests may build up into a massive population on another host, such as spring blooming weeds along roadsides. When the first host plant is cut or becomes tough, plant bugs migrate quickly into cotton and growers are faced with a full-blown plant bug problem just a day or two after checking clean fields. Flowers also are attacked by some plant bug species, causing warty growths on flower petals and brown spots on stamens and pistils. Plant bugs lay eggs inside cotton stems near the top of the plant. The pests usually lay very small eggs in groups that normally are impossible to detect.

Life cycle: The rapid plant bug and tarnished plant bug: eggs - 10 days; nymphs - 15 to 20 days; number of life stages - five. Clouded plant bug: eggs - 12 to 14 days; nymphs - 10 to 18 days; number of life stages - five.

All plant bugs are multiple-host insects and spend most of the season on other hosts, which they prefer over cotton. Tarnished and rapid plant bugs overwinter as adults in ground trash near host plants. The clouded plant bug overwinters in the egg stage in the stems and stalks of host plants of various kinds. These pests are referred to as "true bugs" by entomologists because they do not pass through a larval or worm stage, and they do not go into the pupa or resting stage. When true bugs hatch, they resemble the adults except for size and often the absence of wings.

Critical timing of control measures: Treatment thresholds for tarnished plant bugs depend on stage of crop development and method of sampling. During the pre-bloom stage, thresholds may be adjusted downward if square retention drops below 80%.

Stage of Crop Treatment Threshold:

• Pre-squaring - 1 bug per 10 feet of row
  
• 1^st 2 weeks of squaring - 8 bugs/100 sweeps
  
• 3^rd week of squaring to bloom - 15 bugs/100 sweeps
  
• after first bloom - 15 bugs/100 plants or 3 bugs per 6 row feet
  

Yield losses and Prevalence: Tarnished plant bugs may be found in all Mississippi cotton fields. Prolonged heavy TPB infestations can result in substantial yield reductions. In research plots, yield reductions of 15% to 55% have been documented for plants infested with one to four bugs per plant. During the past ten years, estimated annual yield losses attributed to plant bugs in Mississippi cotton have ranged from 0.2% to 3.6%, with losses as high as 4.7% being reported for the Mississippi Delta.

Chemical Control Information:

Control Alternatives . Novaluron is an IGR type material, currently under development, that has shown good activity against plant bugs in research trials. The unregistered product known as fipronil also has proven to be very effective against tarnished plant bugs.

Both indoxacarb (Steward) and emamectin benzoate (Denim), which are primarily caterpillar insecticides, have activity against tarnished plant bugs. However, these products are generally less effective than those recommended specifically for plant bug control. There are many other products, including most pyrethroids and several organophosphates, that will control non-resistant plant bugs, but their overall utility is limited because of widespread resistance. Although thiacloprid (Calypso) and acetameprid (Assail) have some activity against plant bugs, preliminary results indicate that they are less effective than thiamethoxam (Centric).

Cultural Control Practices: Border vegetation management is the most important cultural control for plant bugs. Plant bugs can build up on flowering plants growing around field borders and move into cotton fields when these more favored hosts are destroyed or senesce. Timely mowing of such source areas can aid in reducing available hosts for plant bugs. Such mowing must be initiated before cotton is planted. Mowing after such weed hosts begin forming flower buds will only force plant bugs into adjacent cotton. Research involving the use of broad spectrum herbicides applied, on an area-wide basis, to turn rows, ditch banks, and other areas bordering cotton fields has shown some impact on plant bug numbers in cotton. However, the ecological and environmental impacts of this approach have not been addressed.

Thick, heavy canopied stands of cotton tend to have increased numbers of plant bugs and management practices such as avoiding excessive seeding rates or over fertilization can aid in plant bug management.

Nectariless varieties of cotton have been proven to harbor lower populations of plant bugs than varieties with nectaries, but this trait is not commercially available.

Biological Control: Compared to pests such as aphids and tobacco budworms, tarnished plant bugs have relatively few parasitoids and predators, and conservation of beneficial insects within cotton fields provides relatively little benefit in managing plant bugs. Collectively, spiders are the most common predators of plant bugs. Plant bug infestations are seldom flared by applications of insecticides for control of other pests, but absence or reduction in sprays for other pests can increase the potential for plant bugs to exceed economic thresholds.

APHIDS

Aphids are a secondary pest in cotton. Aphids tend to be a greater problem in cotton when early applications of insecticides have been made to control boll weevils or plant bugs. The insecticides destroy beneficial parasites and predators that normally suppress aphid populations. In some years aphids have cause severe problems for cotton growers.

Frequency of occurrence: Aphids tend to be a frequent pest of a portion of Arkansas cotton each year.

The damage done by the pest: Heavy infestations cause curling or crinkling of leaves. Aphids feed on the youngest, most tender growth and, when present in large numbers, will cover terminals. During the principal blooming period, aphids may cause older leaves to turn yellow and shed. Severe infestations can cause heavy yield/quality losses.

Life cycle: Female aphids give birth to live young. Females continuously reproduce without a male. The pests can multiply rapidly under high temperatures and may develop the equivalent of a new generation every five days.

Critical timing of control measures: Treat when populations are building and aphids are present on approximately 50% of the plants. Aphid treatments will be more effective when applied in combinations. Do not apply pyrethroids prior to July 1. Use systemic in-furrow insecticides at planting to suppress early season aphids.

Yield losses and Prevalence:
Cotton aphids occur in all Mississippi cotton fields each year. However, the severity of infestation can vary greatly from year to year. Fields that receive multiple applications of insecticides for plant bugs or other pests during June are more likely to experience aphid outbreaks, but aphids can also build to damaging levels on fields that have received no early season insecticide treatments. The yield impact of aphid infestations can vary considerably, depending on environmental conditions. In some research trials no yield loss resulted from heavy infestations exceeding 100 aphids per leaf. However, yield losses as high as 220 lbs of lint per acre have been documented for extremely heavy, prolonged aphid infestations. In recent years estimated yield losses attributed to aphids have ranged from 0.2% to 0.9%.

Chemical Control Information:

Control Alternatives: Carbofuran (Furadan) is highly effective against cotton aphids and has been used successfully in a number of Section 18 Emergency Exemptions. Acetamiprid (Assail), Thiacloprid (Calypso) and Pymetrozine (Fulfil), are products that are currently under development which show promise for aphid control.

Cultural Controls: During dry years, irrigation may aid in reducing aphid induced stress, relative to that experienced in non-irrigated fields. Excessive nitrogen fertilization may increase the potential for aphid outbreaks.

Biological Controls:
Biological control is the primary method of controlling aphids. Aphids are attacked by a number of predators and parasitoids, which normally keep aphid populations from reaching damaging levels. When these beneficial insect populations are destroyed by early season insecticide sprays targeting other pests, such as boll weevils or tarnished plant bugs, the potential for an aphid outbreak is increased. However, aphid outbreaks do occasionally occur in fields that have received no previous insecticide treatments. Regardless of whether they reach outbreak levels, aphid populations in Mid-South cotton are naturally controlled by the entomopathogenic fungus, Neozygites fresenii. Epizootics of this disease occur each year during mid-season, causing dramatic crashes in aphid populations, and usually providing effective suppression of aphid populations for the remainder of the season.

Stink Bugs:
Southern Green Stink bug: Nezara viridula
Green Stink bug: Acrosternum hilare
Brown Stink bugs: Euschistus spp.

Historically, stink bugs were not considered a significant pest of Midsouth cotton because they were controlled coincidentally by the large number of treatments applied to control boll weevils, bollworm/budworms and other pests. However, the reduction in spraying that has occurred as a result of the success of the boll weevil eradication effort and the widespread adoption of Bt-cotton has resulted in increased opportunities for stink bugs to colonize and survive in cotton fields. Thus, the importance of stink bugs as a pest of cotton has increased in recent years, and consultants are finding it necessary to scout and, occasionally, treat for these pests.

Several species of stink bugs may occur in cotton. These include the southern green stink bug, Nezara viridula, the green stinkbug, Acrosternum hilare, and several species of brown stink bugs belonging to the genus Euschistus. Of the brown stink bugs, Euschistus servus, is the most common species found in cotton. Several other species of stink bugs may be found occasionally in cotton fields, but these rarely occur in large numbers.

Biology: Stink bugs are found on a large number of agricultural crops, including soybeans, corn, and grain sorghum. Crops or weeds bearing immature seeds are especially favored. All species overwinter as adults, which emerge in early spring and begin feeding on seed bearing plants, such as wheat, clovers, and various weeds. Small nymphs often feed on vegetative portions of the plants, but larger nymphs and adults prefer to feed on developing seeds. The barrel-shaped eggs are laid in clusters which hatch in seven to twelve days. There are five nymphal instars. Newly emerged nymphs usually remain clustered together, but disperse as they grow larger. Development rate is temperature dependent, but at normal summer temperatures the time to complete one generation is approximately 45 to 50 days. There are approximately three generations per season.

Adult stink bugs are strong fliers. As early spring hosts mature and senesce, stink bugs move from these hosts to other hosts that are in a more attractive stage of development. This results in a sequential movement from early spring hosts, such as clovers or wheat, to early summer hosts, such as soybeans, corn, and grain sorghum, and ultimately to late summer hosts, such as cotton.

As a result, stink bug populations in cotton are usually greatest in late summer due to immigration from nearby early summer hosts. Cotton fields that are located near large plantings of corn, soybeans, or grain sorghum are especially susceptible to invasion by stink bugs. If such cotton fields are receiving relatively few foliar insecticide treatments, the potential for stink bugs to reach damaging levels is even greater.

Damage: Although stink bugs feed on vegetative parts of the plant, and will occasionally feed on squares, feeding injury to bolls is the most common type of stink bug damage to cotton. Both adults and larger nymphs are capable of damaging bolls. Stink bugs have piercing-sucking mouth parts, which they use to pierce the boll wall and feed preferentially on the developing seed. Recent research has shown that bolls less than 350 DD60s, or approximately 18 days, of age are especially susceptible to injury. But stink bugs will feed on older bolls, and the effect of stink bug feeding on the ultimate fate of a boll is highly variable. Depending on the extent of the feeding and the age of the boll, bolls that have been fed upon by stink bugs may be completely destroyed or they may open normally and produce a normal amount of lint.

External signs of stink bug feeding are small, somewhat sunken dark spots on the boll wall, often exhibiting a small pierced area in the center of the spot. This external injury is very similar to that caused by plant bugs. Internal symptoms of the damage include small pierced areas on the inner boll wall, wart-like growths on the inner boll wall, stained lint, and damaged seed. Bolls that have sustained heavy damage usually fail to open, but if heavy damage is confined to one lock, the affected boll may partially open. Often, bolls may exhibit external signs of feeding, without suffering severe internal damage. However, bolls may also exhibit severe internal damage in the absence of external symptoms.

Yield Losses and Prevalence: Low numbers of stink bugs can be found in most Mid-South cotton fields, especially during the latter portion of the growing season. The potential for stink bug infestations is greater following mild winters, which favor survival of the southern green stink bug. Cotton fields located near fields of corn, grain sorghum, or early-maturing soybeans are most likely to experience infestations. Yield effects of stink bug injury are dependent on the percent of bolls damaged. Heavy uncontrolled infestations of stink bugs can cause severe yield loss. Because stink bugs often do not appear in cotton fields until the later part of the growing season, damage is often concentrated in the upper portion of the plant. Historically, the percent yield loss attributed to stink bugs in the Mid-South has been near zero. However, in more eastern states where boll weevil has been eradicated for a number of years, estimates of the amount of yield lost to stink bugs have ranged as high as 3.8%. And, it is anticipated that the importance of stink bugs will increase considerably in the Mid-South in the coming years. Mississippi reported a 0.4% yield loss due to stink bugs in 2001, making it the third most damaging pest of the season.

Control: Effective control of stink bugs depends on the application of foliar insecticide sprays that are applied whenever infestation levels exceed the economic threshold. Although there are some differences between the brown stink bugs and other stink bugs in susceptibility to certain insecticides (brown stink bugs are less susceptible to pyrethroids), stink bugs are relatively easy to control with foliar sprays. However, fields located near plantings of alternate hosts harboring high numbers of stink bugs may require multiple insecticide treatments for adequate yield protection.

Chemical Control Information:

Alternatives: The newly registered product thiamethoxam (Centric) has demonstrated good activity against stink bugs in some research trials. Thiacloprid (Calypso) and acetamiprid (Assail) may also have potential for stink bug control, but additional testing is necessary.

Cultural Control Practices: Trap crops have proven to be a useful method of managing stink bugs in soybeans and would likely be equally useful in cotton. However, logistical and economicalconcerns associated with the use of trap crops have limited their appeal to producers.

Biological Control Practices: Stink bugs are attacked by a number of parasitoids and predators which help limit their population. These include; several species of egg parasitoids, the adult parasitiod, Tricopoda pennipes, and a number of predators. These beneficial insects play an important role in the overall population dynamics of stink bugs, but their ability to control threshold populations of stink bugs is limited.

Other Insect Pests Of Cotton:

Other minor or occassional pests such as spider mites, whiteflies, cutworms, beet armyworms, fall armyworms, and loopers occur sporadically throughout the Mid-South, but do not occur in economically damaging numbers every year. Spider mite outbreaks occur along ditch banks and roadways where the spider mites overwinter on winter weeds and other host plants. Spider mites are a greater problem during growing seasons which average less than the expected rainfall. Cutworms attack newly emerged plants by cutting the young plant at the soil line and pests on field by field basis. Rarely are large numbers of acres affected by cutworms. Beet armyworms and fall armyworms occur primarily in the more southern areas of the region during late summer. Populations of beet armyworms and fall armyworms rarely build up to large populations until late summer. Likewise, loopers, primarily the soybean looper, are occasional, late-season pests that are more common in the more southern areas of the region.

Despite their status as minor or occasional pests, each of these species has the potential to cause severe crop injury when they occur in outbreak numbers. Beet armyworm is an excellent example of this. In 1993 beet armyworm was the most damaging pest of Mississippi cotton, causing an estimated 4.4% yield loss, despite control expenditures of approximately $27/acre. A 50% yield reduction was attributed to a serious outbreak of beet armyworms that occurred in the Lower Rio Grande Valley of Texas in 1995. Therefore, it is critical to maintain knowledge of IPM tools that can help prevent these minor and occasional pests from reaching outbreak levels and to maintain an arsenal of insecticides that will be effective against these minor or occasional pests when outbreaks do occur.

Seedling diseases of cotton cause serious losses to cotton producers in Mississippi each year. A Cotton Disease Council estimate shows Mississippi producers lose an average of 3 percent of their total crops to seedling diseases. The estimate does not include the cost of replanting.

Seedling disease identifies a complex situation involving the interaction of several organisms and the environment. Certain fungi that cause these seedling diseases are carried either on or in the seed. Other fungi live from season to season in the soil and can attack the seed or seedling. The organisms that cause seedling disease are found in all cotton-producing areas of the United States, but populations differ from area to area. Soil-borne pathogens most commonly involved in the seedling disease complex in the Southeast are Rhizoctonia, Fusarium, and Pythium.

Identification Of Seedling Diseases:

Seedling diseases may cause many different effects on cotton plants. These may be grouped into three general phases.

SEED ROT:
A number of organisms in the soil and on or in the seed can cause seed to rot. Seed decay can result from poor handling of seed during harvest or from poor storage conditions. Such seed tend to be low in ability to live and easy prey for seed-rotting organisms.

SEEDLING ROT:
Preemergent seedling rot describes the loss of a cotton seedling to disease between the time the seed germinates and emerges from the soil. The infection is usually seen as a soft rot or lesions on the expanding root and stem.

DAMPING OFF:
Postemergence damping off is a phase of the disease occurring at any time during the first part of the growing season. "Soreshin" is another name for this stage of the disease.

At first, plants are stunted and lighter green than normal. As the disease progresses, the plants begin to show midday wilting, and lesions appear near the soil line. These lesions are light brown at first but turn progressively darker until the whole area takes on a black "wire stem" appearance. These plants eventually die, leaving an uneven stand.

Control:

Seed Treatments:
All cotton seed used for planting should be treated with a fungicide. Seed-treatment fungicides are sold individually or in combinations of two fungicides under a single trade name. In combinations, one fungicide is active against Rhizoctonia, while the other is active against Pythium. Because several disease-causing organisms may be involved with seedling disease, the use of more than one seed-applied fungicide is suggested.

The materials most commonly used in the Midsouth are Apron, Thiram, Vivatax-PCNB, RTU-Baytan/Thiram, Baytan 30, and Biological Fungicide Product-Kodiak Concentrate.

Soil Treatments:

1. Planter Box - Planter box is the least effective of the soil treatments, but it is better than no additional treatment. If equipment is not available for in-the-furrow fungicide applications, use a planter box treatment. Following are the most common materials used in the Midsouth:

Method of Application - Soil fungicides cannot be applied well by the hopper-box method with acid-delinted seed unless the seeds and fungicide are properly layered in planter box.

When mixed well with seed, some fungicide will fall out with each seed to treat the soil around it. Fungicides may reduce the seedling rate by 10-20 percent, so you must calibrate the planter with the seed and fungicide mixture to get the desired seeding rate.

The hopper-box method is less expensive than in-furrow spray and in-furrow granules, but the method is also less effective. When used properly, the method gives better results than do seed treatments alone.

2. In-the-Furrow Granules - In-furrow granules have given about the same degree of seedling disease control as in-furrow spray applications. Granular fungicides that are recommended include the following:

3. In-the-Furrow Sprays - The process mixes more fungicide with the soil to give a greater zone of protection around the germinating seed and young seedling.

For best results, the fungicide is applied through two cone-type nozzle tips. The front cone-type nozzle is mounted just behind the seed-drop outlet to treat the soil around the seed. Direct the rear nozzle to spray soil as it is tumbled into the seed furrow, with a small amount of spray striking the top of the covered row.

Remember that soil fungicides are used in addition to regular seed treatments, not in place of them. Treated seeds cannot be used for oil, food, or other purposes.

Summary Of Seedling Diseases Control:
Seedling diseases of cotton can be controlled only through the use of preventive measures. All of the control measures are taken before or at planting time.

• Cultural Control - A number of cultural practices lower the risk of seedling disease. Early cutting and shredding of stalks aid in the control of seedling disease by cutting down on the amount of inoculum that carries over from year to year. Also, it is important to prepare a good seedbed for seedling-disease control. Raised beds give some control to seedling disease, especially in early-planted cotton.

• Soil pH - Maintain soil pH 6.0 to 6.5. Extremely low pH favors the development of some cotton seedling diseases. A pH of 6.0 to 6.5 not only encourages vigorous plant growth but also suppresses certain diseases.

• Soil Temperature - Avoid planting when soil temperatures are below 68 °F. At this temperature, germination is slow and the seeds and seedlings are more vulnerable to infection.

• Seed Quality - Poor-quality seeds with low germination rates are much more susceptible to seedling diseases than are high-quality seeds. Seeds with high germination usually produce more vigorous, healthy seedlings even under adverse conditions.

• Seed Treatment - All cotton seeds used for planting should be treated with a fungicide. Seed-applied fungicide helps to prevent diseases caused by organisms carried on the seed surface and is the most important and economical method for controlling seed rot. Seed treatment is not a substitute for high-quality seed but is a supplement.

• Soil Treatment - Soil fungicide is good insurance for getting a good stand of cotton. All producers should use at least a planter-box fungicide in addition to a seed treatment.

If getting a stand (from seedling disease) is a problem one out of three years, an in-the-furrow granular or spray treatment would be economical.

Chemical Control Information:

Three species of nematodes occur in Mississippi that can cause economic yield losses in cotton. These are the root-know nematode (Meloidogyne incognita), the reniform nematode (Rotylenchus reiformis), and the lance nematode (Hoplolaimus spp). In Mississippi, approximately 73 percent of the cotton soil samples submitted udring 2000 tested positive for either root knot or reniform nematodes. Over a twenty year period, root knot nematode presence has remained relatively low. Reniform nematode populations began to increase during the late 1980's and have increased each year since.

The average yield loss caused by these three nematodes species, beyond any control mesures, on Mississippi cotton is 5.3% (1995-2000). The Mississippi Delta suffers from medium to high populations of root-know and reniform nematodes with yield losses proving to be substantial. Research also shows a devinite interaction between reniform nematodes and cotton seedling disease. Total field loss is possible in severe situations.

The symptoms associated with nematodes are often mistaken for other problems such as nutritional imbalance, soil compaction, and water stress. Characteristic root galls are associated with root-knot nematode infection, while reniform nematodes do not cause galls.

Crop rotation is generally the most cost-effective method of nematode control over time, but rotational crops may be of relatively low economic value. Production of rice, corn, grain sorghum, or peanut, or resistant soybean cultivars for one or two years in rotation with cotton may improve crop performance by lowing reniform nematode populations. Careful selection of rotation crops, based on the nematode species to be controlled is essential.

Conventional cotton variesties with root-know Fusarium silt tolerance are Stoneville LA 887, Deltapine 50, Deltapine 51, Suregrow 119 and Stoneville 132. These varieties will perform satisfactorily if the root knot nematode population is not too high. No current cotton varieties are resistant to reniform nematodes. Transgenic cotton varieties are currently being evaluated for nematode resistance.

Chemical Control Information:

Good weed control is not an accident -- it's planned. Successful weed control depends on preparing a smooth, firm seedbed, a vigorous-growing stand of cotton, proper rates and placement of fertilizer, disease control, and a well-limed soil. All of these cotton-production practices contribute to a rapid-growing stand of cotton and ease in weed control.

A planned weed-control program is based on knowledge of the weed problem. Most fields are infested with grass and broadleaf weeds. Herbicides generally do not control both equally well, so preplant, preemergence, and postemergence herbicides along with cultivation usually are needed.

Preplant Incorporated Herbicides:

The herbicides Prowl and Treflan are similar in the weeds they control. Both provide excellent grass control, good control of many small-seeded broadleaf weeds, and poor-to-no control of sedges, large-seeded broadleafs, and most perennials.

Both of these herbicides are fairly volatile. On a warm, moist, windy day, losses from not incorporating for 24 hours average 15 percent for Prowl and 30 percent for Treflan. Poor incorporation is the greatest source of weed control failure. For best control, apply herbicide to a fairly dry, well-pulverized soil, and mix thoroughly. Application to soils that have not been tilled results in high herbicide losses and poor incorporation. Two passes with the equipment to incorporate 1 to 2 inches deep are generally preferred. Since these herbicides can prevent normal development of small cotton roots, incorporation on a preformed row reduces injury.

Cold, wet weather, excessive rates, low organic matter soils, seedling disease, banded fertilizers, and other herbicide applications may intensify cotton injury.

Incorporation:

Tests of some commercial incorporators indicate that ground-driven band equipment gives incorporation approximately half the incorporation depth. With power-driven, rotary-tiller-type incorporators, the chemical is applied to the depth the machine operates. Rotary hoes, rolling cultivators, or gang disks are used on a broadcast basis. You will get better results by making two passes over the field with rotary hoes or rolling cultivators. If you use gang disks, they should run no deeper than 3 inches. The spray boom is usually mounted on the tractor and the chemical applied at the first disking. The second or cross disking is sometimes postponed until nearer planting time.

Maintain a speed of 3 mph or more with ground-driven incorporating equipment. Some of the equipment described may not be listed on company labels, so read labels carefully before incorporating herbicides.

Preemergence Weed Control:

Preemergence herbicides are applied at planting, before weeds emerge, to provide control during cotton emergence and early growth.

Preemergence herbicides control most small-seeded, annual broadleaf weeds and grasses such as crabgrass, pigweed, barnyardgrass, and lambsquarter. Preemergence herbicides alone will not effectively control many of the larger-seeded annual broadleaf and perennial weeds, such as cocklebur, morningglory, trumptercreeper, and nutsedge.

Since preemergence herbicides normally are applied on the soil surface after planting, little or no weed control occurs until they are moved into soil by rainfall. If rainfall is delayed, a light rotary hoeing sometimes improves performance but must be done without damaging the cotton.

All preemergence herbicides can damage young cotton or reduce or destroy stands if high concentrations of the herbicides come in contact with the germinating seed or young seedling. Cotton appears to be more tolerant to Zorial and Cotoran and least tolerant to diuron and cyanazine. This depends on soil type, organic matter content, and amount and timeliness of rainfall the first two weeks after planting.

Limit damage by planting high-vigor seed and firmly covering with ½ to 1 inch soil. Set planters to shape the row so that rainfall will run to the row middles instead of funneling the water and herbicide toward the seed.

Preplant Plus Preemergence Herbicide:

Better control of a variety of weeds, including grasses and broadleaf weeds is obtained, by using both a preplant incorporated herbicide and a surface preemergence herbicide. Apply separately and use according to label directions.

It is strongly recommended that you select and use a combination of preplant and preemergence herbicides that controls or suppresses the expected weed problems. Controlling escaped weeds using hoe labor or over-the-top herbicides can be very costly.

Crop, weed, or situation and active chemical per treated land acre	Formulation needed to treat 1 acre broadcast	Time of application	Weeds controlled	Special instructions and remarks
Postharvest/Fallowbed/Preplant Foliar Postharvest/Fallowbed or preplant foliar herbicide applications are designed to provide residual control of winter annuals or burndown of existing vegetation. Applications can be made during or after fall tillage, up to various time intervals prior to planting, depending on which herbicide is used. Fall application of residual herbicides can reduce the need for spring tillage or spring burndown herbicides. However, exceeding maximum use rates in any one year is possible with certain herbicides. Also, fall application of most herbicides eliminates the possibility of fall cover crops becoming properly established.
norflurazon at 0.8 to 1.25 lb/A	Zorial Rapid 80 -- 1.0 to 1.5 lb/A	Surface applied in fall after final disking or bed formation	Annual bluegrass, chickweed, bittercress. Poor control of henbit and Carolina geranium.	Do not exceed broadcast rates of 1.25 lb/A for light soils, 1.9 lb/A on medium soils, or 2.5 lb/A on heavy soils in any one year.
trifluralin at 1.0 to 1.25 lb/A	4 lb/gal formulation -- 2 to 2.5 pt/A	Apply and incorporate any time between Oct. 15 and Dec. 31. May be left flat or bedded.	Annual bluegrass, chickweed, henbit, other winter annuals.	Do not apply to wet soils or soils subject to prolonged flooding.
pendimethalin at 0.75 to 1.0 to 1.5 lb/A	Prowl/Pendimax 3.3 EC -- 1.8 to 2.4 to 3.6 pt/A	After Oct. 15 up to 140 days prior to planting.	Most winter annuals and other small-seeded annuals.	Incorporate within 7 days of application if rainfall does not occur. Do not apply to wet soils or soils subject to prolonged flooding.
cyanazine at 1.5 to 2.5 lb/A or 0.5 lb/A	4 lb/gal formulation -- 1.5 to 2.5 qt/A or 0.5 qt/A	30 to 60 days prior to planting, or 7 days prior to planting if 0.5 lb/A is used.	Residual control of most winter annuals including annual bluegrass, henbit, chickweed, cutleaf evening primrose. Burndown of weeds less than 3 inches tall if surfactant at 0.25% v/v is added.	Use 1.5 qt/A on loamy sands with less than 2% organic matter. Use 2.0 qt/A on loamy sands with more than 2% organic matter or on other soils with less than 2% organic matter. Use 2.5 qt/A on other soils with more than 2% organic matter. Use 0.5 qt/A on medium to heavy soils with more than 1% organic matter up to 7 days before planting. Adding Gramoxone, Roundup, or MSMA will improve burndown of emerged weeds when the 0.5 lb/A rate is used.
dicamba at 0.188 to 0.25 lb/A	Clarity 4AS 6-8 fl oz	Preplant for vegetation knockdown.	Cutleaf eveningprimrose, buttercup species, clovers, Pennsylvania smartweed, & other winter annual weeds.	Consult label to determine rates for weeds and growth stages. Include nonionic surfactant at 0.25% v/v. If applied in the spring following a fall application the total amount applied cannot exceed 2.0 lb ai/A. Clarity applied as a preplant burndown treatment must be applied at least 21 days before planting. Consult label for added restrictions following a fall application.
oxyfluorfen at 0.25 to 0.5 lb/A	Goal 2XL -- 1.0 to 2 pt/A in a minimum of 20 gal water by ground.	Early fall up to 7 days prior to planting.	Residual control of most winter annuals, especially henbit. Postemergence control of henbit, common groundsel, and shepherdspurse up to 4-leaf stage with the addition of suitable surfactant. Fair control of chickweed.	Use lower rate for short residual (late winter, early spring) application. Use higher rate for long residual (fall, early winter) applications. Soil must be tilled to depth of 2 inches before planting unless treatment is 30 days or more prior to planting and unless at least three rain falls of ¼-inch or more have fallen since the application. For best preemergence activity, rainfall or irrigation should occur within 3 to 4 weeks after application and soil should be left undisturbed during the period of desired weed control.
prometryn at 0.75 to 1.0 lb/A	4 lb/gal formulation -- 1.5 to 2 pt/A with crop oil concentrate at 1 pt/A	Nov. 1 up to 30 days prior to planting.	Residual control of most winter annuals and postemergence control of small (less than 2 inches) existing vegetation.	Use high rate for early applications, low rate for applications nearer to planting. Use crop oil concentrate if vegetation is present at time of application. If weeds are larger than 2 inches, addition of Gramoxone or Roundup may improve control. Do not make multiple applications to exceed seasonal maximum rate for cotton.
thifensulfuron + tribenuron at 0.225 to 0.45 oz/A	Harmony Extra -- 0.3 to 0.6 oz/A with nonionic surfactant at 1 qt per 100 gal spray mix.	After weed emergence but 45 days prior to planting.	Post emergence control of broadleaf winter weeds such as curlydock, chickweed, henbit, and buttercup.	Apply to young actively growing weeds. Allow 1 to 3 weeks after application for full control. May be mixed with other preplant herbicides to broaden weed spectrum.
glyphosate/sulfosate at 0.5 to 1.0 lb/A	1 to 3 pt Roundup Ultra 4AS or 0.75 to 2.33 pt Touchdown 5AS	After weed emergence up to 3 to 7 days before planting. Touchdown must be applied at least 35 days before planting.	See chart below. Consult label for complete list of weeds controlled.	Include 0.25% v/v nonionic surfactant with Touchdown. Use higher rate for larger weeds or heavy infestations. Use of flood-jet nozzles is not suggested. If tillage is intended after treatment, wait at least 3 days (7 days for rhizome johnsongrass). Cultivation before johnsongrass emergence will result in better control after glyphosate application. Rainfall within 6 hours after application may reduce control. Heavy rainfall within 2 hours after application may require repeat treatment to obtain control. Avoid drift to nearby crops or areas not intended to be treated. Do not use with galvanized (zinc coated) spray equipment. Apply a preplant or preemergence herbicide to control johnsongrass from seed.
	*Perennial and annual ryegrass require 64 oz per acre for control.
MSMA at 2.0 lb/A	MSMA -- 2.7 pt of a 6 lb per gal formulation in 10 to 20 gal water. Add 1 qt nonionic surfactant to each 100 gal of spray mix unless formulation contains surfactant.	After weeds emerge but before planting cotton.	Most annual grasses and cocklebur. Weak on most other broadleaf weeds. Top kill of johnsongrass.	Useful where planting was delayed and weeds have emerged. Control decreases in cool weather. Cotton may be planted immediately after spraying.
paraquat at 0.625 to 0.94 lb/A	Gramoxone Extra (2.5 lb/gal) -- 2 to 3 pt in 20 gal water by ground equipment or 5 gal by air. Add 1 qt surfactant per 100 gal water.	For burndown of existing vegetation before planting, but before weeds reach 6-in. height.	Top kill of most annual and perennial weeds and grasses. Perennials will regrow.	Paraquat is nonselective so avoid spray drift onto desirable vegetation. Use low rate on weeds under 2 inches tall.
Preplant Incorporated
norflurazon at 1 to 1.5 to 2 lb/A	Zorial 80 DF -- 1.25 to 1.9 to 2.5 lb in 10 to 20 gal water.	Within 30 days of planting.	Most annual grasses and small-seeded broadleaf weeds. Good to excellent control of prickly sida and good control of spurred anoda.	Incorporate no deeper than 2 to 3 inches after beds have been reduced for planting. Do not use where johnsongrass or morningglory is a major problem. Incorporation offers potential advantages over surface application: 1.better control under early season dry conditions 2.better suppression of deep germinating weeds such as cocklebur and morningglory 3.better suppression of perennials such as nutsedge and bermudagrass. The application also may be split with ½ rate preplant incorporated and the other ½ on the surface after planting.
pendimethalin at 0.5 to 0.75 to 1.5 lb/A	Prowl/Pendimax 3.3EC -- 1.2 to 1.8 to 3.6 pt in 5 gal water by air or 10 gal water by ground equipment.	From 140 days to immediately before planting.	Most annual grasses and small-seeded broadleaf weeds such as pigweed and purslane.	Increase rate by 0.6 pt/A on coarse and medium textured soils where heavy weed populations are anticipated. Use 3.6 pt/A on heavy clay soils. Incorporate 1 to 2 inches deep immediately after application for best results. A 15% loss can occur if incorporation is delayed 24 hours. When making band applications, avoid removal of treated soil from the seedbed during incorporation and planting.
trifluralin at 0.5 to 0.75 to 1.0 lb/A	4 lb/gal formulation -- 1 to 1.5 to 2 pt or 5 lb/gal formulation -- 0.8 to 1.2 to 1.6 pt in 5 gal water by air or 10 gal water by ground equipment.	Anytime after January 1 to immediately before planting.	Most annual grasses and some small-seeded broadleaf weeds such as pigweed and purslane.	Incorporate 1 to 2 inches deep immediately after application for best results. A 30% loss can occur if incorporation is delayed 24 hours. When making band applications, avoid removal of treated soil from the seedbed during incorporation and planting.

Estimated Levels of Preplant Foliar Weed Control Normally Expected

^*Plus approved adjuvant according to label instructions.

Estimated Levels of Weed Control Normally Expected ^a

^aRatings assume the herbicides are applied in the manner suggested in the guidelines and according to the label under optimum growing conditions.

Postemergence and Layby:

Success or failure of the cotton weed-control program is largely related to the attention given to the post-directed spray program. There are a few cases where over-the-top applications must be made.

The herbicides Assure II, Fusilade DX, Poast Plus, and Select can safely be applied at almost any stage of cotton growth. Over-the-top applications of MSMA, DSMA, Cotoran, or Meturon are risky and should be avoided unless absolutely necessary.

The preplant and preemergence herbicide programs keep weeds controlled until cotton is more than 3 inches tall. When cotton is 3 to 5 inches, program to control escaped weeds and add additional preemergence herbicide to the soil. Directed sprays should be applied with minimal cotton foliage contact to avoid injury.

Surfactants:

Surfactants generally are added to postemergence herbicides to enhance control of actively growing weeds. Some herbicide formulations already contain surfactant. Consult the label before adding surfactant to the spray solution. Most herbicides require 1 quart of surfactant (85% ± 10% active ingredient) per 100 gallons of spray solution. However, some herbicides require as much as 4 quarts per 100 gallons. Consult the label to determine the correct surfactant rate.

Crop oil concentrates (COC) are not routinely suggested for use with directed sprays in cotton. COC use is required with Cobra herbicide. Several cases of cotton injury have been observed when a COC was substituted for surfactant and used on small cotton.

Spray Volumes. The recommended spray volume is 5 to 10 gallons by air and 10 to 20 gallons by ground equipment. In fields with dense populations of large weeds, a volume of 1 gallon per inch of treated band may be needed for good spray coverage. Control with Roundup Ultra, Poast Plus, and Fusilade DX is usually better when the lower recommended spray volumes are used. Thorough spray coverage is essential for acceptable weed control. Spray volume does not usually affect weed control if the correct herbicide rate is applied uniformly and as recommended.

Layby and Spot Treatment Herbicides:

Recall the number and rates of postemergence herbicides that were used before making layby applications. Where rotation is not a consideration, late-season weeds are expected to be troublesome; or where stands are erratic, layby herbicides should be used. Read the label for the maximum amount of a herbicide that can be used. Do not exceed this amount in any one year.

Two methods of layby herbicide application are recommended. Use a split application where perennials, such as redvine, nutsedge, and johnsongrass, are not a problem. Make the first application with one-half the recommended rate when cotton is 10 to 15 inches tall. Apply the other half rate at the normal layby time or when the cotton is 18 to 24 inches tall. In most fields, cultivation after the first application will not be needed. A single, late-season application of the full rate is preferred when the late cultivation is used to suppress perennials.

Of the layby treatments suggested, diuron and Bladex are the most economical. Diuron is much more persistent than Bladex. The selection of a layby herbicide program should be based on weeds present, crop rotation restrictions, cotton stands, and economics.

Crop, weed, or situation and active chemical per treated land acre	Formulation needed to treat 1 acre broadcast	Time of application	Weeds controlled	Special instructions and remarks
Postemergence -- directed Many of the suggested postemergence treatments include MSMA with another herbicide for broader spectrum weed control. Costs can be reduced by omitting the MSMA where nutsedge, cocklebur, or grasses are not a problem. When omitting MSMA in the spray mixture, be sure to add surfactant. Use of the arsenical herbicides (DSMA and MSMA) is limited to two applications whether used alone or in combination with other herbicides. Timely directed applications are preferable to over-the-top applications because of better weed control and less cotton injury. DO NOT APPLY DSMA OR MSMA AFTER FIRST BLOOM. A number of instances of MSMA/DSMA resistance in common cocklebur have been documented throughout Mississippi.
3-inch cotton or larger
DSMA at 3.6 lb/a or MSMA at 2.0 lb/a	DSMA -- 8.0 pt of a formulation containing 3.6 lb/gal DSMA hexahydrate equivalent in 20 gal water. Add 1 qt surfactant for each 100 gal of spray mix unless formulation contains surfactant or MSMA -- 2.7 pt of a 6 lb per gal formulation in 20 gal water. Add 1 qt surfactant for each 100 gal of spray mix unless formulation contains surfactant.	1 or 2 applications after the smallest cotton reaches a height of 3 inches.	Most annual grasses, susceptible cocklebur, and some other annual broadleaf weeds. Nutsedge and small johnsongrass plants will be top killed. More effective during hot, dry periods than in cool, wet periods. Combinations with other herbicides more effective on goosegrass than when used alone.	DSMA is preferred for the first application when cotton is small or stressed from adverse weather, disease, thrips, etc. Do not apply after first bloom. Addition of fluometuron or prometryn will broaden spectrum of weeds controlled.
fluometuron at 0.8 lb/a (or plus DSMA or MSMA, see above)	4 lb/gal formulation -- 0.8 qt in 20 gal water. Add 1 qt surfactant for each 100 gal of spray mix.	1 or 2 applications when cotton is 3 to 6 inches tall.	Annual grasses and most seedling broadleaf weeds.	Relatively safe on young cotton and also provides residual preemergence weed control.
prometryn at 0.5 lb/a (or plus DSMA or MSMA, see above)	4 lb/gal formulation -- 1 pt in 20 gal water. Add 1 qt surfactant for each 100 gal of spray mix.	Apply 1 or 2 times after cotton is 3 inches tall.	Most seedling broadleaf weeds including prickly sida if sprayed before 2 inches tall. Addition of DSMA or MSMA improves grass control.	Do not apply at the 3-inch stage if cotton is stressed. Provides some residual preemergence control in addition to killing emerged weeds.
6-inch cotton or larger (in addition to herbicides listed for smaller cotton)
cyanazine at 0.6 to 1.0 lb/a (or plus DSMA or MSMA)	Bladex 90DF -- 0.67 to 1.11 lb or 4 lb/gal liquid formulation -- 1.2 to 2.0 pt in 20 gal 200 water. Add 1 qt surfactant for each 100 gal of spray mix.	Apply after cotton is 6 inches tall; before weeds are more than 2 inches tall.	Most seedling broadleaf weeds including cocklebur, prickly sida, morningglory, and pigweed. Addition of DSMA or MSMA improves grass control.	Use as a well-directed basal spray to minimize cotton injury. Use the higher rate of cyanazine as the cotton and weeds become larger. Do not apply cyanazine more than 3 times during the season.
diuron at 0.2 to 0.5 lb/a (or plus DSMA or MSMA)	80% formulation -- 0.25 to 0.62 lb or 4L formulation 0.4 to 1 pt in 20 gal water. Add 1 qt surfactant to each 100 gal spray mix.	1 or 2 applications after cotton is 6 inches tall.	Most seedling broadleaf weeds. Addition of DSMA or MSMA improves grass control.	Apply as directed spray. Diuron plus MSMA provides better weed control under a wide range of growing conditions than either herbicide alone. Use the higher rate of diuron as cotton and weeds become larger. The higher rate provides some residual preemergence control in addition to killing emerged weeds.
lactofen at 0.2 lb/a (or plus DSMA or MSMA)	Cobra 2E -- 0.8 pt in 20 gal water. Add 0.5 to 1.0 pt/A crop oil concentrate for cotton 6 - 8 inches tall or 1.0 to 2.0 pt/A for cotton greater than 12 inches tall.	Apply 1 or 2 times after cotton is 6 inches tall. For best results, spray weeds before 3-inch height.	Most small broadleaf weeds. Addition of MSMA or DSMA improves grass control.	Use as a well directed basal spray to minimize cotton injury. Height differential between cotton and weeds is important since good spray coverage on the weeds is necessary for control.
oxyfluorfen at 0.25 or 0.5 lb/a (or plus DSMA or MSMA)	oxyfluorfen at 0.25 or 0.5 lb/a (or plus DSMA or MSMA)	Goal 2XL -- 1 or 2 pt in 20 gal water. Add 1 qt surfactant for each 100 gal of spray mix.	Most seedling broadleaf weeds including prickly sida, morningglory, and hemp sesbania. Addition of MSMA or DSMA improves grass control.	Good spray coverage on the weeds is essential for control. Oxyfluorfen is most effective under optimum growing conditions. Use the higher rate on larger weeds or under drought conditions.
Postemergence -- Over-the-top
bromoxynil at 0.5 lb/a	Buctril 4 EC at 1 pt/a per application, not to exceed 3 pints per year.	From prior to planting but after weed emergence up to 75 days prior to harvest; up to 1- to 4-inch weeds for broadcast rates.	Excellent postemergence control of most broadleaf weeds especially cocklebur and morningglory. Does not control grasses or nutsedge.	ONLY USE ON COTTON THAT CONTAINS THE BROMOTOL GENE FOR BUCTRIL RESISTANCE (BXN cotton). Do not tank mix with sufactant or other pesticides. Do not use at a rate greater than 1 pt/application for each planted acre of transgenic BROMOTOL cotton. Total cumulative rate should not exceed 3 pt/planted acre.
clethodim at 0.0625 to 0.125 lb/a	Select 2EC -- 6 to 8 oz/a (see table below) in 10 to 30 gal/A by ground or 3 gal/a by air. Add 1 qt/a crop oil concentrate.	Apply to actively growing grasses up to 60 days before harvest. See table below.	Annual and perennial grasses.	Apply over the top or semidirected to cover grasses. Adjust spray volume and pressure to ensure thorough coverage of grass. Do not apply: 1.more than 32 oz/a per season 2.within 1 hour of anticipated rainfall 3.to stressed grasses Do not cultivate within 7 days of application.
DSMA at 1.2 to 3.2 lb/a or MSMA at 0.75 to 1.0 lb/a	1 to 1.3 pt of a 6-lb per gal MSMA formulation or 1.6 to 4.3 pt of 3.6-lb per gal DSMA formulation in 10 to 20 gal water. Add 1 qt nonionic surfactant to each 100 gal of spray mix unless formulation contains surfactant.	Apply when cotton is 3 to 6 inches tall. Do not apply after first square or when cotton is more than 6 inches tall.	Excellent control of susceptible cocklebur and small annual grasses. Poor control of hemp sesbania and prickly sida.	Use as a salvage treatment only. Possible burning and reddish color of foliage may appear. May delay cotton maturity. Do not tank mix with other herbicides. Apply only to healthy cotton under favorable growing conditions.
fluometuron at 0.5 to 1.0 lb/a	4 lb/gal formulation -- 1 to 2 pt. Add 1 qt surfactant for each 100 gal of spray mix.	Apply after cotton reaches 3 inches and weeds are as small as possible.	A wide spectrum of annual weed seedlings controlled or suppressed to allow more effective directed sprays later.	Use as a salvage treatment only. Crop injury may occur. Apply only to healthy cotton under favorable growing conditions. Use the higher rate on vigorously growing cotton and bigger weeds.
fluazifop at 0.094 to 0.188 lb/a	Fusilade DX -- 0.375 to 0.75 pt in a minimum of 5 gal water by air or ground equipment. Add either a crop oil concentrate at 1% or a surfactant at 0.25%.	Apply to actively growing grasses at the appropriate stage of growth. See table below.	Most annual grasses, rhizome johnsongrass and bermudagrass. See table below.	Apply over-the-top of cotton or as a semidirected spray to the grass at rates given in the table below. Adjust spray volume and pressure to ensure thorough coverage of grass foliage. For annual grasses, retreat if needed for late emerging grasses. If regrowth of johnsongrass or bermudagrass occurs following the first application, a second application can be made as indicated in the table. Do not apply more than 48 oz/a/season. Do not apply after boll set or within 90 days of harvest.
glyphosate at 0.5 to 1.0 lb/a	Roundup Ultra at 1 to 2 pt/A.	After weed emergence but before cotton reaches 4-leaf stage. POST-DIRECT IF COTTON IS BEYOND 4-LEAF STAGE.	Postemergence control of most annual broadleaf and grass weeds, including control of johnsongrass. A well-designed preemergence program is recommended for optimum control.	For use only on Roundup-ready cotton. Do not apply over-the-top beyond 4-leaf stage. Allow 2 nodes of growth and 10 days between sequential applications. Do not mix with surfactants. Tropical applications beyond the 4th leaf stage reduces early season fruit retention. Apply as a postdirected spray after 4-leaf stage. Postdirecting does not necessarily ensure tolerance. Use precision with postdirect applications and minimize cotton contact with spray solution. Multiple applications without allowing sufficient growth between treatments and/or improper application causes abnormal fruiting patterns and yield losses.
pyrithiobac at 1.0 to 1.5 oz/a	Staple 85 SP at 1.2 to 1.8 oz/a. Add nonionic surfactant at 1 qt per 100 gal of spray mix.	From 1 true-leaf cotton up to 60 days prior to harvest; after weed emergence up to 1- to 4-inch weeds except sicklepod and prickly sida. See label for sicklepod program. Proper timing is essential to reach expected levels of control.	Excellent postemergence control of most broadleaf weeds. Poor grass control. Apply to prickly sida up to 1 inch tall for adequate control. Thorough coverage of weed foliage and a well-designed preemergence program are recommended for optimum control.	Do not tank mix with insecticides containing malathion. Staple antagonizes grass control with postemergence grass herbicides. Adequate control can be achieved by treating grass 3 to 5 days prior to or 5 to 7 days after Staple application. Apply as a "sloppy" postdirected spray when applying Staple with MSMA or DSMA. Do not tank mix with Dual as a postemergence treatment. Do not exceed 1.8 oz/a in a single application or 2.4 oz/a per season. Do not apply within 60 days of harvest. If rate does not exceed 1.8 oz/a, corn may be planted 10 months after last application, or if rate exceeds 1.8 oz/a, corn may be recropped the following year only if Staple was applied as a 50% or less band and the land is thoroughly tilled after application.
quizalofop at 0.0313 to 0.0625 lb/a	Assure II -- 5 to 10 oz/a in a minimum of 10 gal/a by ground or 2 gal/a by air. Add crop oil concentrate at 1.0% v/v or nonionic surfactant at 0.25% v/v. Use crop oil at 0.5% v/v for aerial application. Use only petroleum based crop oils.	Apply to actively growing grasses anytime prior to 80 days before harvest. See table below for proper rates and grass stages.	Annual and perennial grasses, excellent control of johnsongrass.	Apply over-the-top or semidirected to cover grasses. Adjust pressure and spray volume to ensure thorough coverage of grass. Do not apply: 1.using crop-origin (vegetable) oils as an adjuvant or carrier 2.more than 18 fl oz/a per season 3.within 24 hours of a postemergence broadleaf herbicide. Do not cultivate within 7 days of application.
sethoxydim at 0.19 to 0.28 lb/a	Poast Plus -- 1.5 to 2.25 pt in a minimum of 5 gal water by air or ground equipment. Add a crop oil concentrate at 1 qt/a with aerial and ground applications.	Apply to actively growing grasses at the appropriate growth stage. See table below.	Most annual grasses, seedling and rhizome johnsongrass, and bermudagrass.	Apply over-the-top of cotton or as a semidirected spray to the grass. Adjust spray volume and pressure to ensure thorough coverage of grass foliage. Apply at rates and growth stages given in the table below. If more annual grasses emerge after the first application, then additional applications can be made. A second application can be made to control regrowth of johnsongrass and bermudagrass. Do not apply within 40 days of harvest.
*If spray volume is more than 10 GPA, increase the rate on johnsongrass at first application to 2.25 pt/A.
Cultivation -- use so that the soil moved by it will not interfere with subsequent use of postemergence herbicides. Cultivation will not normally detract from the control obtained from previously applied herbicides, but frequently will offer an economical means of extending or completing control established by herbicides. Deep cultivation (more than 2 inches) usually is not necessary and may damage the crop.
Spot treatment
clethodim	Select 2EC -- 0.25 to 1% + 1% crop oil concentrate	Apply to actively growing grasses up to 60 days before harvest.	Annual and perennial grasses.	Spray to wet foliage but not to point of runoff.
fluazifop	Fusilade DX -- 1% + 0.25% surfactant or 1% crop oil concentrate. See table below.	Apply to all actively growing foliage of 8- to 18-inch johnsongrass or bermudagrass up to 3 inches tall before runners are 8 inches long.	Johnsongrass and bermudagrass.	Spray grass to wet all foliage but not to the point of runoff. Do not apply more than 48 oz/a/season. Do not apply after boll set or within 90 days of harvest.
glyphosate spray	Roundup Ultra -- 1% solution in water for most weeds including johnsongrass. Increase to 2% solution for harder-to-control perennials such as bermudagrass.	Spray to wet foliage of weeds before cotton bolls open.	Johnsongrass, bermudagrass, trumpetcreeper, and most other emerged annual and perennial weeds.	Treatment most effective on large actively growing weeds. Cotton sprayed with herbicide solution will be severely injured or killed. Avoid windy conditions and high pressure to minimize cotton injury. Repeat treatments may be necessary to control weeds resprouting from underground parts or seed. See label for details.
glyphosate rope wick	Roundup Ultra -- 1 gal + 2 gal water. Quantity to use per acre will vary depending on density of weeds. Do not add surfactant to the herbicide solution.	Apply when johnsongrass is at least 18 inches tall and 8 inches taller than crop plants.	Johnsongrass.	Use rope wick made of polyester over acrylic. Position wick bar 2 to 4 inches above crop plants to avoid contact with herbicide-laden rope. Repeat application as needed to control johnsongrass that later grows above crop canopy. Crop will be injured if the herbicide comes in contact with the foliage by dripping or rubbing. Keep ground speed under 5 mph, and reduce speed as weed density increases.
quizalofop	Assure II -- 0.375% + 1% v/v crop oil concentrate or 0.25% v/v nonionic surfactant.	Apply to actively growing grasses up to 80 days before harvest.	Annual and perennial grasses.	Treat plants on a spray-to-wet basis, ensuring good coverage.
sethoxydim	Poast Plus -- 1.5% + 1% crop oil concentrate. See table below.	See table below.	Bermudagrass and johnsongrass.	Mix as shown in table below. Spray grass to wet all foliage but not to the point of runoff. Spray actively growing foliage when johnsongrass is 15 to 20 inches tall and bermudagrass plants do not exceed 6 inches in diameter. Do not apply within 40 days of harvest.
Layby
cyanazine at 0.8 to 1.2 to 1.6 lb/a.	Bladex 90DF -- 0.89 to 1.33 to 1.78 lb or 4 lb/gal formulation -- 1.6 to 2.4 to 3.2 pt in 20 gal water.	After cotton is 12 inches tall.	Most annual broadleaf weeds.	Add 1.0 qt surfactant for each 100 gal spray mix if broadleaf weeds are present at time of the application. Use this herbicide where a shorter residual effect is desired. Do not apply cyanazine more than 3 times during season.
diuron at 0.5 to 1.0 to 1.2 lb/a	80% formulation -- 0.63 to 1.25 to 1.5 lb or 4 lb/gal formulation -- 1 to 2 to 2.4 pt in 20 gal water. Add 1 qt surfactant for each 100 gal of spray mix.	Apply when cotton is at least 12 inches tall.	Most late-emerging annual grasses and small-seeded broadleaf weeds will be controlled if rain occurs within 10 days after treatment. Also, young, actively growing weeds less than 3 inches tall will be controlled.	Apply broadcast spray as indicated. Omit surfactant if no emerged weeds are present at time of treatment. Where the weed problem is light, apply a half rate after the cotton is 12 inches tall and re-treat only if necessary.
pendimethalin at 0.5 to 1.5 lb ai/a	Prowl/Pendimax 3.3EC 1.2 to 3.6 pt per acre depending on soil texture.	Apply to the soil between rows as a directed spray following the last normal cultivation (layby). Destroy existing weeds prior to application.	Most annual grasses and small-seeded broadleaf weeds such as pigweed and purslane.	Avoid spray contact to nonwoody portion of cotton stems and foliage or serious crop injury may occur. Apply at least 60 days before harvest.
Alternative weed management techniques Hooded sprayers -- Using nonselective herbicides with hooded sprayers to avoid contact with the crop may be desirable for weed control in row middles, especially in no-till or conservation tillage systems. Addition of a residual-type herbicide will extend weed control and may negate the need for a layby application made to 12-inch tall or greater cotton.
glyphosate at 1 to 2 lb/a	Roundup Ultra 1 to 2 qt/a	Apply to 6-inch tall cotton using hooded sprayer ONLY. Keep bottom edge of hood in contact with soil surface.	Annual and perennial grasses and broadleaf weeds.	Avoid crop contact with spray solution. Allow 7 days between application and harvest. Do not exceed 8 quarts per acre per season. Tank mixing with triazine or urea herbicides may antagonize grass control.
paraquat at 0.312 to 0.625 lb/a	Gramoxone Extra at 1 to 2 pt/a with 0.25% (v/v) nonionic surfactant of 1% (v/v) crop oil concentrate.	Apply to 6-inch-tall cotton using hooded sprayer ONLY. Keep bottom edge of hood in contact with soil surface.	Annual and broadleaf weeds less than 6 inches tall.	Avoid crop contact with spray solution. Avoid use of spray tips that produce fine spray droplets. (State Label).
Flame Cultivation -- The newer types of burners available for flame cultivation allow use of lower pressures, while maintaining sufficient temperatures for excellent control of weeds coming into contact with the flame. In some cases, one flame treatment is sufficient. However, at least two flamings, 1 to 5 days apart, are generally required for best results, especially for weeds larger than 2 inches. Flame cultivation provides no residual control. Flame cultivation does not control weeds in row middles.
Lp-gas with specialized burner equipment	3 to 5 gal/a at operating pressure of 15 to 30 psi and 3 to 5 mph.	Use in cotton with stems at least 3/16 inch at soil surface (8-inch tall cotton) with water shield delivery at least 7 gallons per acre. In 10- to 12-inch tall cotton, water shield is not necessary.	Annual grasses and broadleaf weeds, especially morningglory.	Be careful to avoid burning equipment, field borders, and perimeter areas. Operate cultivator with staggered burners positioned 6 to 10 inches above the soil surface at a 30- to 45-degree angle and 8 to 10 inches from the cotton stalks so flame strikes the soil surface 2 inches from cotton main stems. Get Extension Information Sheet 1500 for more details.

Estimated Levels of Weed Control Normally Expected^a

Herbicides
Postemergence-directed
Cyanazine	8	8	9	8	8	6	2	0	-	2	8	8	-	1	8	9	8	8	7	8	7	7	-	G
+ MSMA	8	9	9	8	8	9	5	0	6	6	8	9	5	2	9	9	9	8	7	8	7	8	8	F
Cobra	3	3	3	3	3	3	2	0	-	2	2	8	-	5	6	9	8	8	7	8	7	8	-	G
+ MSMA	8	8	8	8	7	9	5	0	6	6	6	9	7	5	9	9	8	9	7	9	7	8	5	F
Prometryn	7	7	7	7	7	7	-	6	6	-	8	8	7	-	-	-	-	-	-	-	-	-	-	G
+ MSMA	8	9	9	8	8	9	5	0	6	6	8	9	6	2	8	9	8	8	4	5	5	7	8	F
Fluometuron	6	6	6	6	6	6	-	5	4	-	7	6	5	-	-	-	-	-	-	-	-	-	-	G
+ MSMA	8	9	9	8	8	8	5	0	6	6	8	9	5	2	8	9	7	6	4	4	3	6	8	F
DSMA or MSMA	7	8	8	4	7	8	5	0	6	6	6	9	2	1	3	3	2	3	1	0	0	0	3	G
Goal	4	4	4	4	4	4	2	0	2	2	2	8	-	2	9	9	8	9	9	7	8	8	-	G
+ MSMA	8	8	8	8	7	9	5	0	6	6	6	9	7	2	9	9	8	9	9	9	5	8	8	F
Diuron	5	5	6	5	5	5	2	0	0	0	4	4	4	1	7	7	4	5	3	4	3	3	8	G
+ MSMA	8	9	9	8	8	9	5	0	6	6	8	9	5	2	8	9	7	7	4	4	4	4	8	F
Postemergence-over-the-top
Assure II	8	9	8	8	9	9	9	9	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	E
Buctril/BXN	0	0	0	0	0	0	0	0	0	0	0	10	9	3	10	6	6	0	9	8	9	9	4	E
Fusilade/Fusion	9	9	9	9	9	9	9	9	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	E
Poast Plus	9	9	9	9	9	9	8	8	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	E
Roundup Ultra/    Roundup Ready*	9	9	9	8	9	9	8	6	8	7	10	8	6	4	8	9	9	9	7	9	9	-	8	G
Select	9	9	9	9	8	9	9	9	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	E
Staple	0	0	0	0	0	6	3	0	3	5	-	7	9	-	9	10	7	6	9	7	9	9	5	G
Layby-preemergence activity
Cyanazine	3	3	3	3	3	3	0	0	0	0	0	4	6	0	7	6	7	4	4	8	5	4	4	G

^aRating scale: 0-3, none to slight; 4-6, fair; 7-8, good; 9-10, excellent; ratings assume the herbicides are applied in the manner suggested in the guidelines and according to the label under optimum growing conditions. Crop tolerance rating scale: E - excellent; G - good; F - fair.

Two applications.

Flame Cultivation In Cotton

Recently, several issues have forced some producers to reconsider the merits of flame cultivation. Increasing herbicide prices, government regulations regarding worker protection, restricted-use pesticide records, public fear of herbicide damage to the environment, lack of acceptable chemical control of certain problem-weed species, and herbicide-resistant weeds are among current factors. These issues, combined with LP gas prices, make this old technology attractive.

Using flame cultivation to control weeds works by destroying cambium cells in seedling plants. The critical temperature to achieve cambium cell destruction is 130 degrees Fahrenheit, and weeds less than 2 inches tall are the ideal size for control.

Flame cultivation without a water shield can safely be used in cotton after plants develop a main stem 3/16 inch in diameter at the soil surface. This stem size correlates with a plant height of approximately 8 to 10 inches. The design of the water-shielded burner in the early 1970's improved cotton tolerance, thereby allowing use of flame cultivation in cotton 5 to 6 inches tall.

The water-shielded burner uses a single flat-fan nozzle positioned above the burner to deliver 7 to 10 gallons of water per acre, as a barrier to prevent heat movement into the cotton canopy.

To control weeds effectively in the cotton row, have the burner perpendicular to the row. Position the burner 8 to 10 inches above the soil surface, angled 30 degrees to 45 degrees to the ground, and spaced approximately 8 to 10 inches from the row. This positions the flame to strike the soil 2 inches from the cotton plant. Set in this manner, the flames strike the soil and move horizontally along the surface across the cotton row, killing small weeds in its path. A burner on each side of the row controls weeds on either side. Burners must be off-set (or tandem to each other) to avoid a plume of heat's rising into the cotton canopy.

Liquid-pressure-type burners should be operated in the 15- to 30-psi range to develop the optimal flame pattern and to prevent flame out. Low pressures are best suited for small cotton or sparse weed populations, while high pressures are best used in large cotton and dense weed infestations.

Keep the tractor speed in the 3 to 5 mph range. Like pressure, use slower speeds in dense weed populations or large cotton, and use higher speeds in sparse weed populations or small cotton. Operation at these pressures and speeds consumes approximately 5 to 6 gallons propane per acre.

Some of the advantages of flame cultivation include:

• Spectrum weed control;
• Repeat treatment as often as desired;
• Low cost;
• No residue;
• No activation required;
• Can flame when too wet to cultivate;
• Controls large, annual morningglory species;
• Provides immediate results; and
• Weed response is independent of environmental stress.

Disadvantages of this method of weed control include:

• No residual control;
• Cotton fruits higher on stalk;
• There are hazards of handling pressurized gas;
• A fire potential;
• Must apply at least twice; and
• The tractor-mounted liquid pressure tank requires frequent refills.

Chemical Control Information"

Preplant Incorporated Treatments for Grasses

Preemergence Treatments for Grasses

Postemergence Treatments for Grasses

Quizalofop (trade name: Assure II)
Clethodim (Select 2EC)
Fluazifop + Fenoxaprop (Fusion)
Fluazifop (Fusilade DX)
Sethoxydim (Poast Plus)

Approximately 25 percent of the cotton acreage receives either a broadcast over-the-top application or is "spot" treated with of one of the grass herbicides listed above.

Quizalofop: Rates - 0.031 to 0.063 lb a.i. per acre, PHI - 80 days, REI - 12 hours

Clethodim: Rates - 0.094 to 0.25 lb a.i. per acre, PHI - 60 days, REI - 24 hours

Fluazifop: Rate - 0.188 lb a.i. per acre, PHI - 90 days, REI - 12 hours

Fluazifop + Fenoxaprop: Rates - 0.094 to 0.188 lb a.i. per acre (fluazifop) and 0.026 to 0.053 lb a.i. per acre (fenoxaprop), PHI - 90 days, REI - 24 hours

Sethoxydim: Rates - 0.2 to 0.3 lb a.i. per acre, PHI - 40 days, REI - 12 hours

BROADLEAVES: Prickly sida (Sida spinosa), Spurred Anoda (Anoda cristata), Velvetleaf (Abutilon theophrasti), Cocklebur (Xanthium strumarium), Pitted Morningglory (Ipomoea lacunosa), Entireleaf Morningglory (Ipomea hederacea var. integriuscula), Pigweed (Amaranthus spp. ), Palmer Amaranth (Amaranthus palmeri), Spotted Spurge (Euphorbia maculata), Smartweed (Polygonum spp.), Sedge (Cyperus spp.)

Frequency of occurrence: Every year.

The damage done by the pests: Competition with the cotton crop for water, sunlight, and nutrients. Weed seeds and plant residues in the harvested cotton can result in economic loss due to grade reduction. In addition, some weeds (e.g., morningglory) can adversely affect the harvesting efficiency of the cotton picker.

Percentage of infested acres (1998): Prickly sida - 52.6%, Spurred anoda - 1.1%, Velvetleaf - 1.1%, Cocklebur - 31.6%, Morningglories - 78.9%, Pigweed - 31.6%, Spotted spurge - 42.1%, Smartweed - 2.6%, Sedges- 4.2%.

Life cycle: Summer annuals

Critical timing of control measures: To best prevent cotton yield losses, broadleaves should be controlled as early as possible. Preplant incorporated and preemergence applications of these herbicides provide good early season control of most broadleaves. Postemergence applications of certain herbicides will also control the broadleaves that escape early season applications.

Yield losses attributed to broadleaves: Prickly sida - 10%, Spurred anoda - 2%, Velvetleaf - 1%, Cocklebur - 10%, Morningglories - 25%, Pigweed - 10, Spotted spurge - 14%, Smartweed - <1% , Sedges - 5%. Yield loss estimates do not include the costs associated with controlling or managing the pest(s).

Preplant Incorporated Treatments for Broadleaves

Preemerge Treatments for Broadleaves

Postemerge Treatments for Broadleaves

Alternatives:

Alternatives to pesticides for weed control in cotton include mechanical cultivation, hand labor, and flame cultivation. Virtually all of the cotton acres are mechanically cultivated to control weeds (broadleaves and grasses). Hand labor is used on approximately 34 percent of the cotton acreage to control weeds. Flame cultivation is used to control weeds on a small percentage of acres (0.2%).

Spot spraying is used on a small number of acres to control weeds. In these cases only the infested areas of a field receive a pesticide application.

ENVIRONMENTAL ISSUES:

The Mississippi Office of Pollution Control of the Mississippi Department of Environmental Quality is responsible for environmental regulatory control in Mississippi. Their annual report stated that the largest percentage of fish kills is caused by low dissolved oxygen conditions with the least percentage being to pesticide misuse. There was only one fish kill from agricultural pesticide sources and one from the misuse of a termiticide. The report stated that many fish kills were the result of natural causes; and, therefore the cause was determined to be natural.

A number of swine facilities have moved into Mississippi, but only in a small area (60 mile radius). To date, no fish kills below these facilities have been documented..

OTHER COTTON INFORMATION ONLINE IN MISSISSIPPI

MSU Cotton Entomology Homepage - http://www.ext.msstate.edu/anr/entpath/cotton/ctninsects/contents.html

• Current Situation
• Overview of Cotton Insect Management in Mississippi
• Cotton Insect Control Guide
• Insect Scouting and Management in Bt-Transgenic Cotton
• Cotton Insect Identification - Pictures of Cotton Insects
• Cotton Insect Situation Newsletter
• Annual Summaries of Mississippi's Cotton Insect Season
• Cotton Insect Scouting Methods
• Annual Cotton Insect Losses and Control Costs
• Winter Temperatures Affecting Insect Populations
• Recent Papers on Cotton Insects in Mississippi
• Mississippi Cotton Pickin Page

Mississippi Cotton Production - http://www.ext.msstate.edu/anr/plantsoil/cotton/cotton.html

• Historical Perspective
• Cotton Fertility
• Variety Trials
• Publications
• Additional Information & Links
• Sand Blasting Damage
• Delta Weather
• Insect Images
• Sprayer Calibration
• Frequently Asked Questions
• Probability of First Freeze Dates
• Yield Estimation by Boll Counts
• Estimating Losses Due to Boll Rot

Cotton Weed Control - http://www.ext.edu/anr/plantsoil/weeds/weedsdir/cotton.html

• Weed Control Guidelines
• Preplant and Preemergence Weed Control
• Postemergence and Layby Herbicides
• Flame Cultivation
• No-Till Production

Agronomics - Dr. Will McCarty
willm@ext.msstate.edu
662-325-2311, Box 9555, MS State, MS 39762

Diseases - Dr. David Ingram
davidi@ext.msstate.edu
601-857-2284, 1320 Seven Springs RD, Raymond, MS 39154

Insect Pest Management - Dr. Blake Layton
blayton@entomology.msstate.edu
662-325-2085, Box 9775, MS State, MS 39762

Weather Outlook - Mark Freeland
bartf@ext.msstate.edu
601-686-3274, Delta Research and Extension Center, Stoneville, MS 38776

Weed Management - Dr. John Byrd
johnb@ext.msstate.edu
662-325-4537, Box 9555, MS State, MS 39762

Economic Outlook - Dr. O. A. Cleveland
cleveland@ext.msstate.edu
662-325-2750, Box 5187, MS State, MS 39762

Cotton Insect Losses - Dr. Michael Williams
mikew@ext.msstate.edu
662-325-2085, Box 9775, MS State, MS39762

Boll Weevil Management Corporation- Dr. Jeannine Smith
jks1@ra.msstate.edu
662-325-2993, Box 9776, MS State, MS

IPM Coordinator - Dr. Clarence Collison
chc2@ra.msstate.edu
662-325-2085, Box 9755, MS State, MS 39762

1. Cotton Insect Control Guide 2001, Mississippi State University Extension Service, Publication 343, 2-01.

2. 2001 Weed Control Guidelines for Mississippi, Mississippi State University Extension Service and Mississippi Agricultural and Forestry Experiment Station, Publication 1532.2-01

3. Cotton Seedling Disease Control, Mississippi State University Extension Service, Publication 802

4. Mississippi Agricultural Statistics, Mississippi Department of Agriculture and Commerce, Supplement 34.

5. MSUCarescom

6. NASS.USDA.GOV

Compiled by:
Edna Ruth Morgan
Extension Professor
Box 9655
Mississippi State, MS 39762
Phone 662-325-8716
email: ruthm@ext.msstate.edu

Acknowledgements

Sincere appreciation is expressed to Dr. Blake Layton, Extension Cotton Entomologist, who gave unselfishly to this project which was being conducted while his wife was undergoing treatment for cancer. Dr. Clarence Collison, IPM Coordinator and Head of Entomology and Plant Pathology at Mississippi State University is thanked for his guidance and many contributions throughout this project. Without the work of all the people involved in cotton production in the great State of Mississippi, this crop profile could not have been compiled. Expressions of gratitude are expressed to each of them.