This summer, Bayer CropScience and the Environmental Protection Agency entered into a voluntary agreement for Bayer to withdraw its registration and cease production of Temik (aldicarb). How will the loss of this chemical affect pest control in cotton?

Speaking at Cotton Incorporated’s Crop Management Seminar in Memphis, Arkansas Extension entomologist Gus Lorenz pointed out that many cotton producers have already eliminated Temik in favor of seed treatment for early season thrips control.

This is due primarily to the convenience of seed treatments versus Temik in-furrow, Lorenz noted. “There are no more stopped up tubes. No more forgetting to fill up the box.”

Lorenz says the transition from in-furrow treatments to seed treatments happened quickly. “In Arkansas, we went from being about 80 percent users of Temik in the 1990s, to less than 1 percent to 2 percent of our acreage being treated. How much the loss of Temik impacts us is questionable.”

According to Lorenz, studies indicated big differences between first generation seed treatment technology and Temik in terms of control of thrips.

“When the seed treatments first came out, we felt the Temik was still better for yield and profit,” Lorenz said. “But as they perfected the seed treatments, we began to see a change. We weren’t seeing the benefit from Temik. The seed treatments are doing just as well as the in-furrow.

“The obvious advantages to the seed treatments is the reduced toxicity and the application issues, which is why our growers made this transition to seed treatments,” Lorenz said.

Temik still comes out on top versus seed treatments for control of secondary pests such as spider mites and aphids, according to Lorenz.

Lorenz pointed to a survey of 150 Southeast cotton producers in 2004-05 which indicated that growers using Temik in-furrow had a 1 in 170 chance of having to treat for spider mites. For growers who relied on seed treatments alone, the odds of treatment went to a 1 in 17, almost a nine-fold difference.

Trials have shown that the use of Temik “did significantly decrease the spider mite population compared to seed treatments and foliar applications,” Lorenz said. “Visual inspection also indicated much less spider mite damage with Temik versus the seed treatments and the foliar applications.”