Photograph of hoary cress.

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About Hoary Cress
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Hoary Cress Consortium  A scientific group exploring the biological control, ecology, and systematics of the Lepidium draba and Lepidium appelianum.



Hoary cress, also called whitetop, is a deep rooted, invasive mustard perennial that poses a threat to both crop and rangelands in the Western U.S.. Accidentally introduced to North America from western Asia and eastern Europe as a seed contaminant, hoary cress currently infests more than a quarter million acres of public and private land and is found on the noxious weed lists of 14 states and one Canadian province.


In an effort to curb the spread of this noxious weed, several state, federal and international agencies, universities and organizations have joined together to explore biological control options and study the ecology and systematics of this important pest plant. The Hoary Cress Consortium, formed in 2001, includes representatives and researchers from: CABI Biociences, Switzerland; USDA-ARS European Biological Control Laboratory, Montpellier, France; Agriculture, Food and Rural Development, Edmonton, Alberta, Canada; USDA-APHIS-PPQ, Forestry Science Lab, Montana State University, Bozeman, MT; USDA-ARS Northern Plains Agricultural Research Laboratory, Sidney, MT; USDA-ARS Eastern Oregon Agricultural Research Center, Burns, OR; USDI Bureau of Indian Affairs, Billing, MT; USDI Bureau of Land Management, Utah, Montana, Oregon; California Department of Food and Agriculture, Sacramento, CA; Idaho Department of Agriculture, Boise, ID; Oregon Department of Agriculture, Salem, OR; Idaho Fish and Game, Nampa, ID; National Bison Range, Moise, MT; University of Idaho, Moscow, ID; Montana State University, Bozeman, MT; Oregon State University, Malheur Experiment Station, Ontario, OR; Wyoming Weed & Pest, Fremont, Big Horn, Crook and Washakie Counties; and Malheur-Owyhee Watershed Council, Ontario, OR.


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