FQPA-EPA Decision on Lorsban

Rick Weinzierl, University of Illinois, Urbana Illinois

Editor's NOTE: Impact on Agricultural Crops Limited to Tomatoes, Grapes and Apples

The US EPA last week released its revised risk assessment for the insecticide chlorpyrifos (Lorsban and Dursban) and announced an agreement with registrants to eliminate or phase out certain uses. The greatest impact of these actions probably is on uses of Dursban in household and structural pest control, but the use of Lorsban on apples, grapes, and tomatoes also is to be reduced or eliminated. Growers will be able to use Lorsban on these crops as according to existing labels until the end of the calendar year, but the new restrictions will apply next year.

Beginning in 2001, Lorsban application to apples will be restricted to before bloom; no post bloom applications are to remain on the label. Apparently discussion is ongoing over maintaining the legal use of Lorsban as a trunk spray on apples for dogwood borer control (correct timing for this would be after bloom). Similar trunk sprays for control of lesser peachtree borer in peaches were NOT affected by this recent regulatory action. In grapes, residue tolerances will be reduced, and current wording on the EPA announcement of this decision states that only postharvest uses would be allowed to continue.

Our use in the Midwest is for grape root borer control, and the timing for that application is as late as possible up to 35 days before harvest. Because this is a soil application and Lorsban is not systemic, it should not contribute significantly to residues in fruit, but as of now it remains unclear whether or not this use will continue to be allowed. Lorsban will NOT be labeled for use on tomatoes next year.

Co-Editors:Bill Hutchison, Department of Entomology, University of Minnesota, hutch002@tc.umn.edu
Jeanne Ciborowski, IPM Program, Minnesota Department of Agriculture, jeanne.ciborowski@state.mn.us
Cindy Tong, Department of Horticulture, University of Minnesota, ctong@extension.umn.edu
Production Editor: Suzanne Wold, Research Specialist, University of Minnesota, woldx018@tc.umn.edu

Disclaimer
Reference to products in this publication is not intended to be an endorsement to the exclusion of others which may have similar uses. Any person using products listed in this publication assumes full responsibility for their use in accordance with current directions of the manufacturer

Last Revised June 22, 2000.
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