The Black Locust, also called Common Locust, Yellow Locust or Acacia, is a valuable tree, and, when in full bloom, a beautiful forest tree. Unquestionably the best-known American pod-bearing tree.

The Black Locust is found from the mountains of Pennsylvania south to Georgia, west to Iowa and Kansas. It is doubtful this tree is native to New York, but has been extensively planted and has locally escaped cultivation. Being in the Legume Family, the Black Locust fixes nitrogen from the air into nitrates in nodules on its roots.

The Wood of the Black Locust is very durable, and resists rot as well as pressure-treated lumber. Black Locust is the wood of choice for fenceposts and piers

The Black Locust was a favorite tree of George Washington. He wrote about it in his horticulture journals and planted specimens on his estate. Saplings cloned from this National Champion will be planted in the reforestation of George Washington's Mount Vernon estate.

A new organization in central New York is promoting the use of Black Locust lumber as a replacement for pressure-treated timber for outdoor exposures. Pressure treatment disburses toxic chemicals and heavy metals, while the Black Locust has no known toxicity. For more information, visit:

Black Locust Initiative

Identification

Leaves are alternate, compound, 7 to 21 leaflets, 8 to 14 inches long. Leaflts are usually odd in number, short stalked, 1 to 2 inches long.

Flowers appear in May or June, are cream-white, resemble a pea blossom, are arranged in drooping clusters 4 to 5 inches long.

Fruit is a small, dark-brown, thin pod, 2 to 4 inches long, 1/2 inch wide, containing 4 to 8 small brown seeds.

Black Locust Flowers

Bark on both young and old trees is reddish-brown, becomes thick, deeply furrowed.

Twigs are stout, brittle, greenish to redish-brown, bear two short spines at each node.

Buds are small, imbedded in bark, and 3 to 4 occur above each other.

Wood is yellowish-brown, very heavy, hard and durable. It is used for fenceposts, insulator pins, ties, fuel, and ship-building.

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Champion Trees and Ancient Forests — www.championtrees.org — updated: 7/14/2002