CURRENT CROP CONDITIONS
The area cotton crop is continuing on schedule with program fields ranging from 8 true leaves to bloom and boll. Square sets are still ranging from 80% to 100%. With the recent rains, producers are now making irrigation decisions. I would suggest that if you are row water irrigated and it takes you three to four weeks to go across your field, I would probably start irrigating now. Area rainfall amounts for this week range from nothing to 2 inches. Dry land fields that have received over three inches of rain look better than I have seen in five years and there is little or no difference between dryland fields with less than three plants per foot and fully irrigated fields at this time.

WHAT THE SCOUTS ARE FINDING
Pest pressure has stayed the same since the last newsletter and not a single program field is close to economic threshold for any pest but we are shaping up to have some chronic infestations. The scouts are finding fleahoppers ranging from 0 to 6 per 100 terminals. Fleahopper infestations are still wide spread regardless of where the field is located. Remember, that when cotton reaches full bloom the fleahopper is no longer considered a pest. Most of the fleahoppers being found this week are nymphs with very few adults. Lygus bugs are still being found in very low populations in most program fields. Cotton aphids are still being found in the terminal area of plants in most program fields. Beneficial insects are keeping this pest in check and we have not noticed any aphid populations on the undersides of leaves.

Bollworm eggs are still being found in most program fields and are ranging from 500 to 2000 per acre with larvae ranging from 0 to over 4000 per acre. Several program fields are now experiencing chronic infestations of this pest. Square sets in blooming cotton have dropped from 95-100 percent down to a 75-80 percent square set. We are not finding worms larger than three day old worms. And in most cases we are finding the damage to the small squares in the terminal with no worms present. I believe that if the current weather pattern prevails the mortality rate will change and the number of worms per acre will go up once the cotton canopy provides more protection. This could change if we turn off hot and dry causing the mortality rate to increase.

* 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.

The Foundation was very aggressive on our pre-bloom cotton and in many situations cleaned up our thrips fleahoppers and lygus infestations. Going into bloom when conservation of beneficial insects is important they have become less aggressive.

Going into bloom you have an option available to you for keeping your beneficial population intact. Once you receive your phone call that your field is to be treated you can inform the Foundation that you will treat your field yourself with Phaser or Vydate. These materials are promoted as being safer on beneficial insects. However, you have to make two applications of these materials five days apart. I can attest to the fact that once you make three applications with these materials, your beneficial populations will decline.

Program fields that have been treated three times by the Foundation do have a noticeable decline in beneficial insects. It should also be noted that Malathion ULV (product used by the Foundation) is not the best material of choice for bollworm control. Therefore, the fact remains that with a decline in beneficial populations due to multiple applications of Malathion ULV you become vulnerable to bollworm infestations. With that said, my observations thus far concerning fields with increased bollworm infestations do not coincide with fields that have had multiple applications of Malathion ULV. In fact, the program field with the highest bollworm population has not been treated with anything. In addition, this field has the highest beneficial count in the program as well. At this time, I think the key to increased bollworm populations has to do with canopy coverage. I can easily see a direct relationship to canopy size and bollworm numbers. Simply put, the taller cotton with more than 3 plants per foot has more worms.

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