As the Southeastern drought continues, thrips pressure is heavy.

Southeastern Drought Continues
With the exception of a few counties in the Montgomery (Alabama) area, the remainder of the southeast remains extremely dry as of May 23rd. Cotton planting has slowed or stopped where irrigation is not present. In central and south Alabama only about 10% of the cotton acreage is under irrigation.

Cotton Insects
Thrips continue to feed heavily on cotton, even up to and through the five true leaf stage. On May 18, more than 10 thrips per plant were recorded on mid-April planted cotton at Prattville, Alabama. Even cotton planted with Temik at 5#/A needed a foliar spray under this level of pressure. All other at-planting treatments were even more severely stunted. We likely have lost at least 10-12 days of maturity in fields with the heaviest thrips injury.

Cotton Thrips Pressure Heavy, Grasshoppers, and Other Cotton Insects

Cotton Thrips Pressure Heavy


Dry conditions in the coastal plain areas of Alabama and the Southeast have resulted in the migration of tremendous numbers of thrips from wild vegetation and small grains into cotton. All at-planting treatments, in cotton that was planted in April, are being overwhelmed by thrips numbers and injury. Sixty or more thrips can be found on 5 plants within one foot of row. The majority are in the adult stage but immatures are also being found this week.

Due to this continuous migration of thrips, foliar sprays are only holding for 3 to 5 days. However, these sprays are making a big difference from plants that are not receiving foliar applications. Foliar sprays to research plots that received no at-planting treatments have not been adequate in reducing severe thrips injury.

Several different chemicals are being evaluated as foliar sprays for thrips control. At this point, nothing has been as effective as our old standby acephate (Orthene), at 0.2 lb. per acre active.

Grasshoppers

Grasshoppers remain at high levels in the farmscape. Where they are present, controls would be advisable before cotton emerges. Grasshoppers are a threat to stands from the “crook” stage, as the plants emerge, up until about the 5 true leaf stage.

Other Cotton Insects

Ebony bug (Negro bug) immatures have been reported on young cotton in the Talladega County area. Chinch bugs and false chinch bugs have also been reported.

Grasshoppers

Several reports have been received already about grasshoppers in moderate to high numbers in cotton fields that are in the process of being planted in central Alabama. The presence of grasshoppers is not surprising. But the fact that some fields have predominately adults is surprising. Normally the population is almost all immature at this time of the season. Adults usually occur in late May and June. The significance of the life stage is that adults are much more difficult to control. Acephate (Orthene or generics), chlorpyriphos (Lorsban or generics), Dimilin and others give good control of the immature stage. Much higher labeled rates are required to control adults.

Cotton Planting Progress

Some cotton has been planted in many areas of the state. However, weather extremes have interfered with planting in the past 10 days, too much rainfall in the northern areas and too little in the southern areas. No significant rain fronts have occurred in the Wiregrass (southeastern) area in almost a month.


Cotton planted on April 13 at Prattville, AL, is up to a nice healthy stand with most plants putting out the bud of the first true leaf on April 26.

Cotton Scout School Announced

Three cotton scouting schools will be held in Alabama in early-mid June. They are as follows:


June 8, 2011: Autauga County Extension Office, Autaugaville, AL.

June 9, 2011: Wiregrass Research and Extension Center, Headland, AL.

June 14, 2011: Tennessee Valley Research and Extension Center, Belle Mina, AL.

All sessions will begin at 8:30am and continue until noon. Recertification points will be awarded to those in attendance.

Cotton Insect Management 2011

Points for Discussion:
1. Low Input System - Conventional vs. Technology
2. Evolution of Bt Cotton - Various Genes Involved
How do they compare and what is in the future?
3. Phase Out of Temik
What will be the greatest impact?
4. Stink Bug Research Towards a More Rapid Survey Technique
Factors that influence external vs. internal stink bug boll damage.

5. New Damaging Insects
A. Plataspid (Kudzu) Bug

B. Brown Marmorated Stink Bug

C. Redbanded Stink Bug


A. Plataspid (Kudzu) Bug

 Native to Asia

First detected near Athens Georgia in the fall of 2009

Has since spread over much of Georgia, South Carolina and into a few counties in North Carolina and Alabama

Feeds primarily on legumes

Reduced soybean yields by about 20% in 2010 test fields in Georgia

Feeds on stems and leaves

Has high reproductive potential

Can be controlled with pyrethroids and other chemistry

Is a public nuisance problem in fall of the year as they enter homes and buildings to hibernate.

B. Brown Marmorated Stink Bug

First discovered in Pennsylvania in late 1990s

Native of Asia

Big problem in specialty crops in mid-Atlantic states (grapes, apples)

Caused 60-90% loss in peaches and apples in 2010

Called Interstate Bug since it spreads by trucks and campers

Has wide host range - feeds on about everything

Have been found in three Alabama counties in late 2010

Has long proboscis so can go through the husk of corn

Pecans may be huge host in the southeast

Causes more damage per bug on soybeans than green or brown stink bug species

Expect to be economic pest of cotton

Will likely have heavy field edge or border damage
Invades homes for hibernation sites in the Fall

3. Redbanded Stink Bug

Native to South America (Brazil)

First found in Louisiana in 2000

Observed on soybeans in Baldwin County, Alabama in July 2010

Is sensitive to winter temperatures below 20 degrees F

Has high reproductive potential

Is primarily a legume feeder

Can cause heavy damage to soybeans

Feeds earlier and more aggressively than other stink bug species

More difficult to kill than Southern green stink bug

This concludes Week Five of Cotton Insect Management 2011. The slide show can also be viewed at http://www.aces.edu/anr/crops/documents/CottonInsectManagement2011RonSmith.pdf

Cotton Insect Management, 2011

Points for Discussion: 
1. Low Input System - Conventional vs. Technology 
2. Evolution of Bt Cotton - Various Genes Involved 
How do they compare and what is in the future? 
3. Phase Out of Temik 
What will be the greatest impact? 
4. Stink Bug Research Towards a More Rapid Survey Technique 
Factors that influence external vs. internal stink bug boll damage. 
5. New Damaging Insects 
Plataspid (Kudzu) Bug 
Brown Marmorated Stink Bug 
Red-Banded Stink Bug
  
Phase out of Temik:

“EPA and Bayer CropScience, the manufacturer, have reached an agreement to end use of the pesticide aldicarb in the United States.” EPA release October 2010
Remaining uses: During the phase-out, aldicarb use may continue on cotton and peanuts with use-rate reductions and rural well setbacks.  

• Registered in 1970
• Production ends by December 31st, 2014
• Distribution and sales end by December 31st, 2016
• Use ends by August 31st, 2018

 Impact in cotton production: 

• early season insects
• nematodes
• **suppression of spider mites

 Update and Comments on Temik Phase-Out:  

A two-week temporary restraining order affecting the production of a key intermediate used in the production of Temik brand aldicarb was issued February 10 by a federal judge in West Virginia. This order was issued in response to a lawsuit brought about by 16 residents who reside near the production plant. This restraining order was later extended until March 28. Bottom line is the supply of Temik for the 2011 season will be limited.

The point I wish to focus on today is the long term impact of the loss of Temik in cotton insect management. We all recognized the role Temik played in early season insect control, particularly thrips. However, in recent years we have learned how to better utilize seed treatments, supplemented with foliar sprays as needed. 

In addition, growers who continued to utilize Temik were often also benefiting from its nematicideal properties. The loss of Temik will leave a major void in nematode management.

Today, I would like to comment on another benefit of Temik – that being spider mite suppression. In the long haul this may be the most significant loss or impact from the phase out of Temik.

As I have commented to growers in our winter production meetings, there is one advantage of being old and that is you have “seen more history”. In my case I can remember what a major problem spider mites were on cotton in the 1950’s and 60’s. I have seen entire fields in the Tennessee Valley region of Alabama completely defoliated prior to maturity due to spider mite damage. No effective foliar controls were available. Beginning about 1970, when Temik entered the market, spider mites became a relative insignificant pest of cotton for about 30 plus years. Beginning with the movement to seed treatments, mites have become a significant player again. Not in all fields or all years. However, when conditions are conducive, mites can be very economic again. Newer products are now available for foliar control but they do not give extended suppression and most are relatively expensive on a per acre basis. I am not sure that we have anything today that has the mite suppression activity of Temik. Therefore, in the long run, the loss of Temik may leave its greatest impact on mite control. Time will tell.