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This is Jack Bacheler, Extension Entomologist at NCSU with the Wednesday Cotton Insect Hotline tape. Today is Wednesday, May 27.

Cotton in North Carolina now ranges from just being planted to 4 true leaves, and generally looks fair to good. For a change, droughty conditions are not an issue, with soil moisture levels mostly good to occasionally excessive.

Although thrips levels so far have been on the moderate to low side, the activity of seed treatments has run out on any cotton planted more that three weeks ago. Additionally, populations have increased significantly during the past week and some scattered spraying is underway.

We received one confirmed report of difficult-to-control western flower thrips in Gates County this morning identified by Ames Herbert at Va Tech. Because even the highest rates of Orthene or Monitor provide only marginal control of “westerns” and other products fare even worse, our best bet for this species is to hope for continued weather patterns of good soil moisture and warm temperatures. This will help shorten the 1 to 3 leaf window of high cotton seedling susceptibility to thrips damage. Unless population levels are exceptionally high, good control of our far more common tobacco thrips and other thrips species can be expected with insecticides.

As soon as a thrips spray is indicated, the treatment should be made as soon as possible. The same day, if possible. A delay of 3 or 4 days can result in significant damage to seedling cotton if thrips levels are high.

With much of our cotton presently varying from the cotyledon to two true leaf stage, these next two weeks will be the most important period to assess thrips levels and their damage to seedlings. In the case of a successful spray for thrips, remember that leaves already damaged will remain crinkled, so be sure to focus on the newest tiny leaves and in the bud area and the presence of immature thrips before a possible second spray is even considered.

If warm moist weather continues, some of our cotton will have reached the thrips-safe 4 to 5 true leaf stage by this time next week. In the meantime, this is the prime time to walk cotton fields for thrips damage.

Other than the slugs and burrower bugs reported last Friday’s Pest News, no other significant cotton insect pests have been reported or observed by our project personnel.

That’s it for this week. See you next week on June 3.