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Whitetop

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Whitetop (hoary cress)
Hoary cress (whitetop) - Photo by Steve Dewey; Utah State University
Scientific Name: 
Lepidium draba L. Desv. (formerly known as Cardaria draba) (ITIS)
Common Name: 
Whitetop, hoary cress, whiteweed, peppergrass, heart-podded hoarycress, hoary cardaria
Native To: 
Eurasia (Zouhar 2004)
Date of U.S. Introduction: 
1800s (Zouhar 2004)
Means of Introduction: 
Possibly introduced as an ornamental (Zouhar 2004)
Impact: 
Crowds out native species and reduces crop yields (Zouhar 2004)

Distribution / Maps / Survey Status

University of Georgia. Center for Invasive Species and Ecosystem Health.
Provides state, county, point and GIS data. Maps can be downloaded and shared.
USDA. APHIS. Cooperative Agricultural Pest Survey. National Agricultural Pest Information System.

Images

University of Georgia. Center for Invasive Species and Ecosystem Health.

Videos

Google. YouTube; Utah State University Extension.

Selected Resources

The section below contains highly relevant resources for this species, organized by source. Or, to display all related content view all resources for Whitetop.

Council or Task Force
Alberta Invasive Species Council (Canada).
See also: Fact Sheets for more information about individual invasive species, including those listed as "Prohibited Noxious" and "Noxious" under the Alberta Weed Control Act

California Invasive Plant Council.

In online book: Bossard, C.C., J.M. Randall, and M.C. Hoshovsky (Editors). 2000. Invasive Plants of California's Wildlands. University of California Press. Berkeley, CA
Partnership

USDA. APHIS. PPQ. Center for Plant Health Science and Technology; California Department of Food and Agriculture.

University of Idaho.
University of Georgia. Center for Invasive Species and Ecosystem Health.
Texas State University System. Texas Invasive Species Institute.

Centre for Invasive Species Solutions; Atlas of Living Australia; Australian Government. Department of Agriculture, Water and the Environment.

Federal Government
USDA. FS. Rocky Mountain Research Station. Fire Sciences Laboratory.
USDA. NRCS. National Plant Data Center.

USDA. ARS. National Genetic Resources Program. GRIN-Global.

State and Local Government
Washington State Noxious Weed Control Board.
California Department of Food and Agriculture.
See also: Included on California's noxious weed list; see Encycloweedia: Program Details for additional resources
Lincoln County Noxious Weed Control Board (Washington).
See also: Weed I.D. and Options for Control for more species

Colorado Department of Agriculture. Conservation Services Division. Noxious Weed Program.

Academic
Professional
Colorado Weed Management Association.
Montana Weed Control Association.

Citations

  • Integrated Taxonomic Information System. Lepidium draba. [Accessed Sep 10, 2014].
  • Zouhar, K. 2004. Cardaria spp. In: Fire Effects Information System. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory.