Transformational Gardening

Black Locust (False Acacia) (Robinia pseudoacacia): Images

Date Location Notes Images
October 11, 2010 Southeastern, New Hampshire On the bike trail looking for acorns, I came across a group of small Black Locust trees. Black Locust has black-tinted bark, the leaves are arranged alternately on the stem with each leaf having many large, oval untoothed leaflets (pinnately-compund). At the base of each leaf are two very sharp thorns. The leaf stem (petiole) is swollen where it attaches to the branch (between the thorns). The thorns are prominent on young trees and apparently are not prominent on older, larger trees. In the Spring, the Black Locust will produce white, pea-like flowers.

There are two other Robinia species in New Hampshire:
  1. Bristly Locust (Rose Acacia) (Robinia hispida): Similar to Black Locust but has very long, red hairs on stems and has a pink-colored, pea-like flower.
  2. Clammy Locust (Rose Acacia) (Robinia viscosa): Similar to Black Locust but has the braches are covered with numerous, sticky short-stalked red glands and has a pink-colored, pea-like flower.
In addition, the Black locust has similarity to the Honey Locust (Gleditsia triacanthos). It is once or twice pinnately compound leaves. The leaflets are not nearly as broad as the Black Locust leaflets. The Honey Locust has numerous, sharp 3-part or multi-part branched thorns.

The Black Locust tree is prized for firewood (extremely dense wood), fence posts (resistant to moisture and rot), furniture (low rate of expansion/contraction), hardwood floors, support timbers (great structural strength).

While most of the plant, including the bark is considered toxic, the flowers have been traditionally used for tea to treat rheumatism and can also be used in making jam and pancakes. Small doses of the bark are considered a tonic by some, while larger doses of the bark are considered emetic and purgative. More information on the uses of Black Locust can be found in the Plants for a Future database and Henriette's Herbal web page.
Date Location Notes Images
August 28, 2011 Southeastern, New Hampshire
Date Location Notes Images
May 29, 2012 Southeastern, New Hampshire
Date Location Notes Images
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