Robinia pseudoacacia

Robinia pseudoacacia_Black locust_JM DiTomaso
Photo courtesy 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.

Rating: Limited

Cal-IPC Resources

  • 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.
  • CalWeedMapper - Statewide maps, climate models, and reports.
  • Cal-IPC News - Our quarterly newsletter. Each issue is available as a pdf.
  • Cal-IPC Symposium Proceedings - Presentations and papers from our annual Symposium.
  • Don't Plant a Pest! - Select your region to find non-invasive alternatives to ornamental species. Also see our statewide brochure on trees.

Other Resources

Symposium Presentations

  • Connick, S. and M. Gerel (2004). Partnering to prevent invasions of plants of horticultural origin. California Invasive Plant Council Symposium 2004. Ventura, CA.
  • Hunter, J. C., J. C. Sterling, et al. (2003). The abundance and distribution of non-native woody species in Sacramento Valley riparian zones. California Invasive Plant Council Symposium 2003. Kings Beach, CA.
  • Reichard, S. H. (1996). What traits distinguish invasive plants from non-invasive plants? California Exotic Pest Plant Council Symposium '96. San Diego, CA.

Cal-IPC News Articles

  • Connick, S. and M. Gerel (2005). Don't sell a pest: A new partnership to prevent plant invasions through horticulture. Cal-IPC News. 13: 4-5,14.