Dimethoate Use in Arizona—Cotton

Date: March 7, 2006
To: Teung F. Chin, OPMP, USDA
Through: Al Fournier and Rick Melnicoe
From: Peter Ellsworth, University of Arizona/Arizona Pest Management Center

Subject: Dimethoate Use in Arizona

I'll respond on behalf of AZ cotton only at this point. Dimethoate is a niche compound that is not relied on a large number of acres. However, when it is indicated, it is sometimes the best alternative for control for a wide array of pests including some unusual ones found mainly in AZ. Its use window is almost exclusively "early", from planting through about pinhead square. Late applications are very rare. Multiple applications are also very unusual; however, preserving the option for a follow-up application 14 d later would be beneficial to our growers.

In short, a 2-application limit would be acceptable to our growers. Most would be applied by ground early in the season and during a very dry period of the year (April - June). Targets would include thrips, fleahoppers and other mirids, flea beetles and aphids, as well as some less common pests like crickets, grasshoppers, and darkling beetles.

Please let me know if additional information is needed.

Peter

Peter C. Ellsworth, Ph.D.
Full Specialist & IPM Coordinator
University of Arizona &
Arizona Pest Management Center
Department of Entomology
Maricopa Agricultural Center
37860 W. Smith-Enke Road
Maricopa, AZ 85239
peterell@ag.arizona.edu
Tel: 520-381-2225
FAX: 520-568-2556
http://cals.arizona.edu/crops