CURRENT CROP CONDITIONS
The area cotton crop is continuing on schedule with program fields ranging from 6 true leaves to bloom and boll. Square sets are still ranging from 80% to 100%. Most fields are either being irrigated at this time or are being set up for irrigation. At the time of this writing, we are experiencing light showers with as much as 1 inch of irrigation expected. With that said, you row irrigated producers still need to get started with your irrigation if your cotton is going into bloom. Dry land fields are still plugging along and weather damaged fields (wind, hail) have repaired themselves and are setting fruit at a rapid pace.

WHAT THE SCOUTS ARE FINDING
Pest pressure has picked up somewhat since the last newsletter but not a single program field is close to economic threshold for any pest. The scouts are finding fleahoppers ranging from 0 to 6 per 100 terminals. Fleahopper infestations at this time are 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 are an even mix of adults nymphs. 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 1000 per acre.

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, Tracer 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.

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