Public Comment Needed for Hawkweed Biocontrol Agent

I would like to announce that the USDA-APHIS has posted the “Notice of Availability of an Environmental Assessment for the Release of Cheilosia urbana” (for the biological control of invasive hawkweed) in the Federal Register, May 28th.  Information regarding this EA may viewed via the following link: 

There is a 30 day public comment period ending June 27, 2019. Those who wish to comment on this potential field release may submit comments by either of the following methods:

The root-feeding hoverfly Cheilosia urbana will attack all invasive hawkweed species. The fly has one generation per year with the larvae feeding externally on the roots. Feeding by C. urbana can significantly reduce the numbers of bolting plants, flower heads with ripe seeds, stolons, and the above-ground biomass of meadow hawkweed. Several non-target plants, such as native Hieracium species were also utilized at very, low levels in laboratory and field tests; with no significant impact occurring. This environmental assessment considers the effects of, and alternatives to, the field release of the fly into the contiguous United States. APHIS is making the environmental assessment available to the public for review and comment, in accordance with the National Environmental Policy Act (NEPA).


Jeff Littlefield

Montana State University

Department of Land Resources & Environmental Sciences