SafePlants

Astragalus lentiginosus: Freckled Milkvetch, Spotted Locoweed, Rattleweed, Loco Weed

Astragalus lentiginosus, a member of the Fabaceae (Pea) family, is a fascinating plant with several common names, reflecting its diverse appearances and historical reputation.

Considerations for Pets

• The plant is also known as Rattleweed and Loco Weed. The seed pods may be of interest to pets.

Considerations for Children

• The plant is also known as Rattleweed and Loco Weed. The seed pods may be of interest to children.

Taxonomy and Nomenclature

• Scientific Name: Astragalus lentiginosus Douglas ex Hook.
• Family: Fabaceae (also known as Leguminosae or Pea Family)
• Common Names: Spotted Locoweed, Freckled Milkvetch, Rattleweed, Loco Weed, Specklepod Milkvetch
• Synonyms: A. lentignosus diphysus (Gray.) M.E.Jones
• Varieties (examples):
  • Astragalus lentiginosus var. palans (Freckled Milkvetch)
  • Astragalus lentiginosus var. albifolius M.E. Jones – Northern Freckled Milkvetch, Owen's Valley Milkvetch, Northern Speckledpod Milkvetch
  • Astragalus lentiginosus var. latus (M. E. Jones) M. E. Jones - Broad-pod Freckled Milkvetch
  • Astragalus lentiginosus var. negundo – Box Elder Freckled Milkvetch
  • Astragalus lentiginosus var. idriensis - Freckled Milkvetch, New Idria Milk
  • Astragalus lentiginosus var. fremontii a/k/a Fremont's Milkvetch

Distribution and Habitat

• Native to western North America.
• Found in dry, open areas, including semi-desert environments.
• Specific locations mentioned include:
  • Mojave Desert (at elevations below 12,000 feet)
  • Canyons of the Ancients National Monument
  • John Day River area (John Day Fossil Beds National Monument)
  • San Joaquin Valley (growing under the shade of oaks and junipers)
  • Great Basin National Park (Nevada, USA)
  • Saline Valley, Death Valley National Park, Inyo Co., California
• Also found in: Canada (British Columbia), Mexico, and the United States (including Alabama, Arizona, Arkansas, California, Colorado, Connecticut, Florida, Georgia, Idaho, Illinois, Indiana, Iowa).

Morphological Characteristics and Growth Habits

• Perennial herb growing from a taproot.
• Height: typically grows to 4 to 20 inches (1.6 to 6 dm or 10 to 51 cm), though some sources say up to 16 inches.
• Stems: Prostrate to ascending, hairless or coated with silver hairs.
• Leaves: Linear to widely oval, divided into 19 oval leaflets, which can be dark green and up to 5/8 inches long.
• Seed pods: Described as 1 inch long, hairy, and freckled with red.
• Blooms: April to July.
• Color: Purple, pink.

Ecological Role

• Grows in dry, open areas.

Further Information

• USDA Symbol: ASLE8
• Dave's Garden (community forum)
• Discover Life (biology, natural history, ecology, identification, and distribution information)
• Garden Guides (plant information, identification, and uses)
• Wikimedia Commons (image source)