Black Locust (Robinia pseudo-acacia)

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Black Locust
Tree. Native to some parts of eastern North America but introduced to New England for erosion control and for its highly rot-resistant wood which was extensively used for fence posts.
Identification:
  • Mature trees have deeply furrowed bark.
  • Branches have short spines and produce flat, brown pods 2-4 in. long that often remain on tree into winter.
  • Leaves are compound and comprised of 7-19 oval leaflets that drop in early fall.
  • Flowers hang in showy clusters and are fragrant.
The Problem:
Spreads fast by root suckers, quickly out-competing native vegetation, especially in floodplains; prefers well-drained sandy soils. Nitrogen-fixing nodules on roots alter soil chemistry of natural sand-plain communities, a rare habitat type in CT.