Robinia pseudoacacia

Robinia pseudoacacia_Black locust_JM DiTomaso
Photo: Joseph DiTomaso

Common names: black locust

Robinia pseudoacacia (black locust) is a deciduous tree (family Fabaceae) that grows to 100 feet tall. Historically planted as a landscape tree, black locust has escaped cultivation and become invasive in California and elsewhere. It can grow on a wide range of sites, but grows best on rich, moist, limestone-derived soils. It does not do well on heavy or poorly drained soils, although it appears to be tolerant of some flooding. Through root sprouts and seedling establishment, black locust creates large stands that displace native vegetation. Its seeds, leaves, and bark are toxic to humans and livestock.

Cal-IPC Rating: Limited?

CDFA Rating: None?


Plant Assessment Form - Information gathered by Cal-IPC on the impacts, rate of spread, and distribution of invasive plants in California. Does not include management information.

Weed Management Notes

  • Management Notes - Information on management techniques and effectiveness from the University of California Cooperative Extension’s Weed Research & Information Center.

Cal-IPC Newsletter Articles

Cal-IPC Symposium Presentations

Presentations are linked where available. Where a presentation is not available, find more information by reading the abstract in the Cal-IPC Symposia Archive.

Other Robinia pseudoacacia Information

  • Bugwood - National database from the Center for Invasive Species and Ecosystem Health at the University of Georgia.
  • CalPhotos - Images of plants taken mostly in California.
  • Calflora - Distribution map and records of this species in California.
  • CalWeedMapper - Distribution map of this species in California with ability to determine regional priorities.
  • EDDMapS - Distribution of this species in North America.
  • Jepson Interchange - Information on this plant's taxonomy, biology, and distribution from UC Berkeley's Jepson Herbarium.
  • USDA PLANTS Database - Information on identification and distribution, with links to websites in individual states.
  • Additional photos

    Robinia pseudoacacia_leaves and flowers_copyright2013_NealKramer
    Robinia pseudoacacia (black locust) leaves and flowers. Photo: &#169 2013 Neal Kramer
    Robinia pseudoacacia (black locust) leaflet tip. Photo: Ron Vanderhoff
    Robinia pseudoacacia_thorns_RonVanderhoff
    Robinia pseudoacacia (black locust) thorns. Photo: Ron Vanderhoff
    Robinia pseudoacacia_growth habit_RonVanderhoff
    Robinia pseudoacacia (black locust) growth habit. Photo: Ron Vanderhoff