hoary cress

Capparales > Brassicaceae > Cardaria draba (L.) Desv
Synonym(s): whitetop, globed-podded hoarycress, peppergrass, whiteweed

Hoary cress, or whitetop, is a perennial forb in the mustard family that can grow up to 2 ft. (0.6 m) tall. The leaves are soft, gray-green, 1.5-3 in. (3.7-7.6 cm) long with fine hairs and heart-shaped bases. The lower leaves tend to have more hairs than the upper leaves. The upper leaves clasp to the stem of the plant. Flowering occurs in early spring to early summer, when white, four-petaled flowers develop in clusters at the apex of the stem. The fruit are heart-shaped seed pods. Hoary cress invades rangelands, pastures, streambanks, and open forests primarily in the western United States, although it does occur in the East. It can form large infestations that can displace native species and reduce grazing quality. Hoary cress is native to Central Europe and Western Asia and was first introduced into the United States in the early 20th century.


Identification, Biology, Control and Management Resources

  • Weeds of the Week - USDA Forest Service, Northeastern Area, Forest Health Protection

Selected Images from Invasive.org

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Plant(s);
Steve Dewey, Utah State University, Bugwood.org
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Feature(s);
Steve Dewey, Utah State University, Bugwood.org
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Feature(s); Roots
Steve Dewey, Utah State University, Bugwood.org
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Flower(s);
Steve Dewey, Utah State University, Bugwood.org
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Flower(s);
Steve Dewey, Utah State University, Bugwood.org
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Fruit(s);
Richard Old, XID Services, Inc., Bugwood.org
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Flower(s);
Chris Evans, River to River CWMA, Bugwood.org
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Plant(s); in flower
Chris Evans, River to River CWMA, Bugwood.org
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Infestation;
Chris Evans, River to River CWMA, Bugwood.org
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Infestation;
Montana Statewide Noxious Weed Awareness and Education Program Archive, Montana State University, Bugwood.org
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Seed(s);
Steve Hurst, USDA NRCS PLANTS Database, Bugwood.org
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Diagram or Graphic; Britton, N.L., and A. Brown. 1913. Illustrated flora of the northern states and Canada. Vol. 2: 165.
USDA PLANTS Database, USDA NRCS PLANTS Database, Bugwood.org
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Invasive Reference(s):

Check Invasive.org for most current lists.
  • Alaska - Noxious Weed Law
  • Arizona - Noxious Weed Law
  • California - Noxious Weed Law
  • California - Invasive Plant Inventory
  • Colorado - Noxious Weed Law
  • Iowa - Noxious Weed Law
  • Kansas - Noxious Weed Law
  • Michigan - Noxious Weed Law
  • Minnesota - Noxious Weed Law
  • Montana - Noxious Weed Law
  • New Mexico - Noxious Weed Law
  • Nevada - Noxious Weed Law
  • Oregon - Noxious Weed Law
  • South Dakota - Noxious Weed Law
  • Utah - Noxious Weed Law
  • Washington - Noxious Weed Law
  • Wyonming - Noxious Weed Law
  • Invasive Plants: Western North America
  • Invasive Plants: Guide to Identification and the Impacts and Control of Common North American Species


External Links


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