SafePlants

Woolly Locoweed: A Detailed Overview

Woolly locoweed, a name often associated with the plant's effect on livestock, is a perennial plant found in various regions of North America. This plant is known for its distinctive woolly appearance and its potential effects on animals that consume it.

Considerations for Pets

• Woolly locoweed contains an alkaloid, locoine, that can cause neurological issues in livestock.
• The plant is known to be toxic to livestock, leading to a condition known as "locoism."
• The plant has fine, short hairs, and its seed pods are described as distinctive white and woolly, which might present a choking hazard if ingested by smaller animals.

Scientific Name and Common Names

• Scientific Name: Astragalus mollissimus
• Common Names: Woolly locoweed, Woolly loco, Woolly milkvetch, Purple locoweed, Crazyweed, Loco

Taxonomy and Nomenclature

• Family: Fabaceae (Legume family)
• Synonyms/Variations:
  • Astragalus mollissimus var. mollissimus
  • Astragalus mollissimus ssp. thompsoniae (Thompson's Woolly Locoweed)
  • Astragalus mollissimus var. bigelovii

Distribution and Habitat

• Woolly locoweed is native to North America, particularly the western and southwestern regions.
• It is found in the Colorado Plateau and Canyonlands.
• Observed in locations such as Utah, Oklahoma, New Mexico, and west Texas.
• Grows in varied habitats, including roadsides, pastures, and desert canyonlands.

Morphological Characteristics and Growth Habits

• A native range/prairie simple perennial plant.
• Exhibits a sprawling growth habit.
• Reaches up to 45 centimetres (1 1/2 feet) in height.
• Leaves are fern-like with 19 to 29 oval to oblong leaflets covered in fine, soft, short hairs.
• Flowers are purple, lavender, yellow, white, pink and pealike.
• Produces distinctive white woolly seed pods.
• Flowers early to mid-spring.

Ecological Role

• It is one of the first Astragalus species to flower in Utah.
• Some species are found in soils high in selenium.

Interactions with Other Organisms

• Grazing animals, such as cattle and horses, are known to consume woolly locoweed, leading to locoism.
• A specialist weevil prefers specific varieties of woolly locoweed.

Further Information

• USDA-NRCS PLANTS Database is a valuable resource.
• Dave's Garden is a community for sharing gardening tips and ideas.
• Discover Life contains information about biology, natural history, ecology, identification, and distribution.