Black Locust

Common Name: Black Locust

Specific Name: Robinia pseudoacacia

Known Occurrence at Taylor Point:

Map area: Roadside 5A

Category: Invasive, Non-Native, Tree

Ecological Considerations:

Black Locust is a fast-growing tree that can grow as high as 100 feet. The diameter of its trunk can grow up to 3 and a half feet across. The bark of the tree is gray to dark brown in color is deeply furrowed. Seedlings and sprouts grow rapidly and are easily identified by long paired thorns. Its roots have nitrogen-fixing nodules.

Black Locust has showy, fragrant white flowers with yellow centers that grow in dense racemes. The fruits are brown, flat dark brown pods, each containing 4-8 reddish brown seeds. The pods develop from September to October and often remain on the tree well into the winter.

Black Locusts are commonly found in open disturbed areas, pastures, rights of way, alongside roads, and in vacant lots. It prefers full sun and sandy, well-drained soils. It does not grow well in poorly-drained areas.

Problems Posed by this Plant:

Robinia pseudoacacia spreads rapidly via root suckers. It can quickly crowd out native vegetation. When the trunk or roots are damaged, it will sprout new growth from the damaged areas.
Its seedlings also grow rapidly. It has been reported to grow up to 2 feet per year and forms tall, dense, monotypic stands. It also produces copious nectar, which enables it to compete effectively with other species for pollinators.

When growing in sandy areas, Black Locust enriches the soil by means of its nitrogen-fixing nodules. This nitrogen fixing capacity may alter soil chemistry.

Native Species Affected by this Plant:

Factors Affording a Competitive Advantage to this Plant:

Black Locust is extremely fast-growing, spreads efficiently though its network of root suckers, and will readily sprout vegetatively when damaged, as well as propagating by seed.

Propagation Mechanisms and Related Issues Affecting Efforts to Remove and/or Eliminate this Plant from Taylor Point:

Black Locust mostly spreads by vegetative root suckers, though it can also spread via mechanical dispersal of its seeds.

Documented Best Removal Practices and Options/Pros and Cons of Various Options:

Case Studies of Removal Efforts, Lessons Learned and Recommendations:

Additional Photos: