Browse and Shop

Where they're from

Crafting a bowl

Home > Locust Tree
Robinia pseudoacacia, commonly known as the black locust, is a tree of the genus Robinia in the subfamily Faboideae of the pea family Fabaceae. It is native to the southeastern United States, but has been widely planted and naturalized elsewhere in temperate North America, Europe, Southern Africa and Asia and is considered an invasive species in some areas. A less frequently used common name is false Acacia, which is a literal translation of the specific epithet. The black locust is native in the United States from Pennsylvania to northern Georgia and westward as far as Arkansas and Oklahoma, but has been widely spread. The tree reaches a height of seventy feet, with a trunk three or four feet in diameter and brittle branches that form an oblong narrow head. It spreads by underground shoots. The leaflets fold together in wet weather and at night; some change of position at night is a habit of the entire leguminous family. With a trunk up to 0.8 m diameter (exceptionally up to 52 m tall and 1.6 m diameter in very old trees), with thick, deeply furrowed blackish bark. The leaves are 10–25 cm long, pinnate with 9–19 oval leaflets, 2–5 cm long and 1.5–3 cm broad. Each leaf usually has a pair of short spines at the base, 1–2 mm long or absent on adult crown shoots, up to 2 cm long on vigorous young plants. The intensely fragrant (reminiscent of orange blossoms) flowers are white to lavender or purple, borne in pendulous racemes 8–20 cm long, and are edible. The fruit is a legume 5–10 cm long, containing 4–10 seeds. Although similar in general appearance to the honey locust, it lacks that tree's characteristic long branched thorns on the trunk, instead having the pairs of short spines at the base of each leaf; the leaflets are also much broader.

The wood is extremely hard, resistant to rot and durable, making it prized for furniture, flooring, paneling, fence posts and small watercraft. Wet, newly-cut planks have an offensive odour which disappears with seasoning. As a young man, Abraham Lincoln spent much of his time splitting rails and fence posts from black locust logs. Flavonoids in the heartwood allow the wood to last over 100 years in soil. In the Netherlands and some other parts of Europe, black locust is one of the most rot-resistant local trees, and projects have started to limit the use of tropical wood by promoting this tree and creating plantations. It is one of the heaviest and hardest woods in North America.
Black locust is highly valued as firewood for wood-burning stoves; it burns slowly, with little visible flame or smoke, and has a higher heat content than any other species that grows widely in the Eastern United States, comparable to the heat content of anthracite. It is most easily ignited by insertion into a hot stove with an established coal bed. For best results it should be seasoned like any other hardwood, however black locust is also popular because of its ability to burn even when wet.[9] In fireplaces it can be less satisfactory because knots and beetle damage make the wood prone to "spitting" coals for distances of up to several feet. If the black locust is cut, split, and cured while relatively young (within ten years), thus minimizing beetle damage, "spitting" problems are minimal. It is also planted for firewood because it grows rapidly, is highly resilient in a variety of soils, and it grows back even faster from its stump after harvest by using the existing root system.