Experimental permit requested for corn herbicide

MADISON

The public can comment until Friday, May 13, on a request for an experimental use permit for two corn herbicide products that contain isoxaflutole, an active ingredient that kills weeds. The products can be distributed and used in Wisconsin, but only with restrictions that most other states do not impose.

Bayer CropScience has asked for an experimental use permit to determine if one of the restrictions on Corvus® and Balance Flexx® can be relaxed without harming surface water. This experimental use permit applies only to the area within 66 feet of standpipes. Standpipes are vertical drainage pipes used in low spots where water may pool. They have holes in them where water enters and drains to an underground tile drainage system.

The company would apply the products to a tile-drained field in Dane County, including 1.1 acres around 4 standpipes, during the 2016 and 2017 growing seasons. The water draining from the system will be monitored for isoxaflutole levels.

Although products containing isoxaflutole have been registered with the U.S. Environmental Protection Agency since the early 2000s, they have been prohibited in Wisconsin until now because of concerns about their potential to contaminate water. The Department of Agriculture, Trade and Consumer Protection very recently registered them for use in eight Wisconsin counties, with very specific restrictions, including their use near standpipes. These products can be applied within 66 feet of standpipes only if they are immediately worked 2-3 inches into the soil or if the field is managed using no-till, high crop residue practices.

Under the experimental use permit process, the department may authorize uses of pesticides for research. The department has completed an environmental assessment on the proposed use near the four standpipes and found no potential environmental harm that would require risk mitigation measures beyond those listed on the product label. Monitoring will also be conducted.

For a copy of the assessment, call or email Otto Oemig, 608-224-4547, otto.oemig@wi.gov. The assessment can also be viewed in the Agricultural Resource Management Division at the department weekdays 7:45 a.m.-4:30 p.m. The address is 2811 Agriculture Drive, Madison, 53718-6777. Comments should be emailed or mailed to Otto Oemig at the above street or email addresses.

Those received by 4 p.m. May 13 will become part of the preliminary environmental assessment record.