CURRENT CROP CONDITIONS
The area cotton crop is continuing on schedule with program fields ranging from first bloom to cutout. Irrigation is in full swing at this time with several program fields cutting out a little too early. Dryland producers could have really used a rain last week. I think we are past the point for precipitation to add substantial yield increases to the dryland crop.

WHAT THE SCOUTS ARE FINDING
Since last week, the pest pressure has subsided for most producers. Lygus bugs are still being found in very low populations in most program fields. I have not heard of any economic infestations in the County thus far. Historically, this pest can occur in high numbers during full bloom. Cotton aphids are still being found in the terminal area of plants in most program fields and are starting to move to the undersides of the leaves in a few locations. With all the pyrethroid applications that went out last week, I feel fairly certain that some fields will have to be treated for this pest. Another concern that I have is the lack of beneficial insects in the fields at this time. Beneficial numbers have decreased in the last two weeks in fields that have not been treated with an insecticide. This decline is leaving the door open for aphid and bollworm infestations. Bollworm eggs are still being found in most program fields and are ranging from zero to 1000 per acre. As a whole the egg lay has declined across the County although I am hearing reports of an egg lay in the Western Counties of the High Plains.

Larvae are ranging from 0 to 10,000 per acre. Many of the worms being found are in fields of very lush cotton where coverage, especially by aerial application was a problem. Another contributing factor was that many of these worms were protected from insecticide applications in the bloom tags around the bottom portion of the plant. In fields that have cutout and are shedding the small squares and bolls at the top of the plant, the economic threshold should be raised. In fields that have cutout, the threshold should be 10,000 to 20,000 worms per acre depending on the availability of small squares and bolls as a food source for developing larvae.

COTTON APHID CONTROL STRATEGIES
With the aphid populations coming up, I thought it advantageous to discuss control strategies. Control decisions will ultimately be based on number of aphids per leaf and coverage. If you have lush cotton that has covered the middles or if you have to make an aerial application then coverage and thus overall control will become an issue. Control can be compounded by the number of aphids per leaf. If coverage is an issue, then you should really start your treatments at 50 per leaf. I should mention that 50 aphids per leaf at first glance looks more like ten. Most producers do not really notice aphid populations until they surpass 100 per leaf making control more difficult.

Historically, Furadan, Bidrin, Bidrin + Ovasyn and Bidrin + Curacron have been our products of choice when aphid numbers have surpassed economic threshold and coverage is an issue. For 2002 we have a section 18 for the use of Furadan. The advantages of this product are its effectiveness and cheap price. The disadvantages are the 14 day re-entry interval, you must post the field and only two applications can be made per year.

Bidrin and the Bidrin "mixes" have a proven record of control. I would not go lower than the 8oz. rate when used alone. The major problems with this product are price and inconsistency of control.
The newer products that are available include Provado, Centric and Intruder. In my opinion Provado should only be used on populations below 75 per leaf and where coverage is not an issue. Centric provides decent control of aphids but may take a little longer to knock the population below threshold. Intruder is a promising product that has been labeled for 2002. The rates of this product fall from 0.6 to 2.3 ounces per acre. The 0.6 rate is compatible with Furadan dollar wise but may lack in control in lush cotton. If you are going to use Intruder at the low rate, then I would target my application at 50 per leaf and use a ground rig. The biggest advantage to the newer aphicides are the reduced reentry intervals compared to Furadan.

* The synthetic pyrethroid insectidides recommended for control of bollworms also will control boll weevil. However, application intervals similar to those recommended for the traditional phosphate insecticides (3 to 5 days under heavy pressure) are necessary to provide adequate control. When treatments are to be made for a bollworm-boll weevil complex a suggested treatment regime is to use a pyrethroid followed 3 to 5 days later by a phosphate or carbamate boll weevil insecticide.

Since pyrethroids are not more effective than organophosphates or carbamates for boll weevil control, but are more effective for bllworm control, they should be saved for bollworm management. We do not recommend using pyrethroids for boll weevil control alone or for early season pests because increased use may contribute to the development of resistance to pyrethroids. Bifenthrin suppresses spider mites when used for control of bollworms. The use of synthetic pyrethroid insecticides may increase cotton aphid numbers.

PEST MANAGEMENT CONTROL STRATEGIES WITH BOLL WEEVIL ERADICATION

First off, we need to clear up some misconceptions that I hear on a daily basis while talking to producers. The first and most popular misconception is a spray schedule. The foundation is not going to spray your field every seven days once your field is targeted for application. The next misconception is that the foundation is not spraying your entire area once one weevil is found.

There is a simple set of events that has to happen for your field to be treated by the Eradication Foundation. Before Monday July 8th, the Foundation was using as their trigger one weevil per field. The foundation would then treat that field and every field within 1/4 of a mile. After Monday July 8th the Foundation is still using a trigger of one weevil per field. The Foundation will then treat that field and the adjacent field.

Control of cotton aphids with various insecticides, RR2200, Rex Isom Farm, Idalou, Texas. 2000.

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