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National Invasive Species Information Center
U.S. Department of Agriculture
Home / Terrestrial Invasives / Terrestrial Plants / Hairy Whitetop

Hairy Whitetop

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Hairy whitetop
Hairy whitetop, plants in late season in fruit - Photo by Joseph DiTomaso; University of California - Davis
Scientific Name: 

Lepidium appelianum Al-Shehbaz (formerly known as Cardaria pubescens) (ITIS)

Common Name: 

Hairy Whitetop, Hoary Cress, Globe-podded Hoary Cress, Ball Cress, White-top lens, Peppergrass

Native To: 

Eurasia (Mulligan and Findlay 1974)

Date of U.S. Introduction: 

First discovered in 1919 (Mulligan and Findlay 1974)

Means of Introduction: 

Introduced accidentally with contaminated alfalfa seed (Mulligan and Findlay 1974)

Impact: 

Crowds out native species and crops (Zouhar 2004)

Distribution / Maps / Survey Status

Early Detection & Distribution Mapping System (EDDMapS) - Hairy Whitetop
University of Georgia. Center for Invasive Species and Ecosystem Health.
Provides state, county, point and GIS data. Maps can be downloaded and shared.

Images

CalPhotos - Lepidium appelianum
University of California - Berkeley. Digital Library Project.
Google Images - Hairy Whitetop
Google.
Invasive.org - Hairy Whitetop
University of Georgia. Center for Invasive Species and Ecosystem Health.

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 Hairy Whitetop.

Council or Task Force
Fact Sheet: Hoary Cress (Jan 2014) (PDF | 983 KB)
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
Partnership
Federal Noxious Weed Disseminules of the U.S. - Fact Sheet: Cardaria pubescens

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

Hoary Cress Consortium
University of Idaho.
Invasive Plant Atlas of the United States - Hairy Whitetop
University of Georgia. Center for Invasive Species and Ecosystem Health.
Federal Government
Fire Effects Information System (FEIS) - Cardaria spp.
USDA. FS. Rocky Mountain Research Station. Fire Sciences Laboratory.
PLANTS Database - Hairy Whitetop
USDA. NRCS. National Plant Data Center.
U.S. National Plant Germplasm System - Lepidium appelianum

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

State and Local Government
Encycloweedia: Data Sheet - Lepidium genus
California Department of Food and Agriculture.
See also: Included on California's noxious weed list; see Encycloweedia: Program Details for additional resources
Academic
Weed Control in Natural Areas in the Western United States: Hoary Cress (Whitetop), Lens-Podded and Hairy Whitetop (2013) (PDF | 252 KB)
University of California. Weed Research and Information Center.
See also: Weeds in Natural Areas for more information sheets
Biology, Ecology, and Management of Whitetop (Cardaria spp.) (2011)
Montana State University Extension.

Citations