CURRENT CROP CONDITIONS
The area cotton crop is continuing on schedule with program fields ranging from pinhead square to bloom boll. Square sets are still ranging from less than 70% to 95%. Program fields are entering bloom with an average of 8 nodes above upper most white bloom (NAWF) and a range of 6 to 9 NAWF. Compared to last year, we are in better shape. If you remember last year, we went into bloom with an average of 7 NAWF and we reached cutout NAWF=4 two weeks later. Producers who are keeping up with the crops irrigation needs should have an extended bloom period this year.

WHAT THE SCOUTS ARE FINDING
The scouts are still finding fleahoppers ranging from 2 to over 40 per 100 terminals. Fleahopper infestations are still wide spread with very few adults being found. 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 a few of these infestations have moved from the terminals to the undersides of the leaves with a noticeable presence of honey dew. As predicted last week, the beneficial insects are taking their toll on these aphid populations. The average number of Boll weevils per trap rose slightly this week around Ransom Canyon and Lake Buffalo. We did not catch a single weevil in any other locations. Bollworm eggs are still being found in most program fields and are ranging from 1000 to12000 per acre with larvae ranging from 0 to over 5000 per acre. We are still finding very few beet armyworm egg masses but egg masses and larvae are still being found this week in the northern counties of the High Plains.

BOLLWORM MANAGEMENT DECISIONS
With many fields going into bloom and noticeable populations of adult bollworm moths flying around, I thought it appropriate to look ahead towards potential bollworm problems.

Let's discuss our most common problem, the chronic bollworm infestation. Management decisions on cotton that is being "nickled and dimed" by bollworms is difficult at best. Worm populations will rarely exceed over 9000 per acre which eliminates the "no brainer" decision to treat. Fields will generally fluctuate between 1000 and 3000 worms per acre which can eventually drop square set below 60%.

Therefore, at any given time you decide to treat, you are actually targeting between 1000 and 3000 worms per acre. What you actually buy with this application is about 3 to 10 days of relief from worms depending upon the control measure used. So, can the money you spent on the application targeting the 1000 to 3000 worms per acre be recovered from yield that was saved from the small worm population? Probably not. I will agree that the cycle has to be stopped at some time, and all we can depend on is either a massive increase in beneficial numbers or chemical residual. The "friendly" control measures such as Bt products and Larvin are easy on beneficials but are lacking in the extended residual department. The Pyrethroids are devastating to beneficials but can give extended residual activity. If Pyrethroids are used, cotton aphid populations will more than likely flare well past economic threshold creating yet another management decision. As for the question, when do we break the cycle? I would probably rely on the weekly totals of the worms per acre. If your field receives between 9000 to 10,000 worms per acre over the next couple of weeks, and egg lays of over 1000 per acre are still occurring, and square sets are continually dropping, then the cycle should probably be broken.

* 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 that phosphates 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.

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