Robinia pseudoacacia . Black Locust is a large, deciduous, upright tree. 50' tall, maybe 25' wide at maturity. The shape is oval at first, then becoming more open and irregularly vase-shaped. Branches are armed with spines. Bark dark brown to gray-black, furrowed. Even though it is fast growing, the wood is incredibly hard and rot resistant. The fragrant, white, pea-like flowers are edible raw or cooked, and are excellent bee forage.
This is a very tough, adaptable tree for tough sites. Nitrogen-fixing, and tolerant of very poor soils. Will sucker.