SafePlants

Hairy Rockcress (Arabis hirsuta)

Hairy Rockcress, scientifically known as Arabis hirsuta, is a flowering plant with several common names. It belongs to the Mustard family (Brassicaceae).

Taxonomy and Nomenclature

• Scientific Name: Arabis hirsuta (L.) Scop.
• Family: Brassicaceae (also known as Cruciferae or Mustard Family)
• Synonyms:
  • Arabis eschscholtziana
  • Arabis pycnocarpa
  • Turritis hirsuta
  • Arabis hirsuta var. eschsholtziana
  • Arabis hirsuta v. eschscholtziana
• Common Names:
  • Hairy Rock-cress (also written as Hairy Rockcress)
  • Mountain Rockcress
  • Creamflower Rockcress
  • Eschscholtz's Hairy Rockcress
  • Pacific Coast Rockcress

Distribution and Habitat

• Hairy Rockcress is native to Europe, Asia, and North America.
• It is often found on limestone, chalky grassland, and walls.
• Specific locations mentioned include Minnesota, southeastern Oregon (Steens Mt. Loop Rd), the Burren, Columbia River Gorge, Pigeon Creek Park (Ottawa County, Michigan), and near Anchorage, Alaska.

Morphological Characteristics

• Usually a short-lived perennial, but can also be biennial.
• Typically reaches about 60 cm (approximately 2 feet) in height, although some sources mention smaller plants less than six inches in height.
• Hairy leaves are present on the lower half of the stem, pointing upwards.
• The plant is erect and covered with coarse hairs.
• Basal leaves have short petioles, are oblong to egg-shaped, 1-3 inches long, and have entire to sharply toothed edges with rounded tips.
• Clusters of small white flowers (approximately 1/8 to ¼ inch) with 4 petals are present at the top of the plant.
• It features a basal rosette of hairy, oblong leaves and clasping stem leaves.
• It bears many longish seed pods on the upper half of the stem, close to the stem.