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Noxious Weeds > Leafy Spurge | BioControl of Leafy Spurge

Biological Control Methods for Leafy Spurge

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In Europe and Asia, enough natural enemies have developed over time to control Leafy Spurge without human help. Insects and diseases in the Old World have put such stress on spurge that it remains an insignificant part of the landscape. As is typical, however, this weed's natural enemies didn't travel over to our continent along with the plant. Humans must intervene in order to have that same measure of natural control as found in Eurasia.


Leafy Spurge is potentially our most serious weed problem on range ground. Presently we have about 150 acres of the weed. Ten years ago we only had about 30 acres. It replaces useful forage making ground less productive and in other states has put ranches out of business. At Pineview Reservoir, several insects have been released on leafy spurge with some encouraging results. Aphthona nigriscutis, pictured left, is a very effective flea beetle whose population is growing every year at the site. Since 1999, these beetles have been responsible for an estimated 90% reduction in leafy spurge in a 70 foot circle around the release site. Beetles were spreading and could be found in leafy spurge two hundred feet from the release site. The photograph below was taken at the perimeter of the depression caused by the hungry beetles showing clearly the grass area mostly weed-free.

In Addition, two thousand of the flea beetles, Aphthona nigriscutis and Aphthona lacerosa, along with 100 galls of the fly Spurgia esulae, were released at a site near Snow Basin in 1996. An evaluation of that site showed a 60 percent reduction in leafy spurge plants in the 40 foot area surrounding the release site. Remaining plants were stunted by 50%. As with all of our biological control efforts, we feel that our work will reap rewards long into the future.
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Noxious Weeds > Leafy Spurge | BioControl of Leafy Spurge