Black locust

Scientific

Robinia pseudoacacia (family Fabaceae) is a member of the legume family and like other legumes fixes atmospheric nitrogen via root-nodule symbiosis. The species’s nitrogen-fixation capacity makes it a pioneer in degraded, eroded, or disturbed soils — black locust will colonize bare ground that resists most other tree species.

The native range is surprisingly small — primarily the southern Appalachian Mountains, with smaller populations in the Ozarks. Centuries of deliberate planting have spread the species across:

• Most of temperate North America
• Much of Europe (introduced to France in 1601, now naturalized across the continent)
• China (introduced in the 19th century, now widely planted)
• Many other temperate regions

In its naturalized range outside the [[blue-ridge-mountains|southern Appalachians]], the species is often considered invasive. It spreads vigorously by both seed and root suckering; once established it forms dense thickets that can suppress native vegetation.

Cultural and economic

Black locust is foundational to traditional eastern American outdoor construction. The heartwood is exceptionally rot-resistant — a black locust fence post installed in ground contact will routinely last 50–100+ years before failing. Old American farmsteads still have functional black locust fence and outbuilding posts dating to the 19th century.

Other applications:

• Fence posts — the canonical use; sometimes called “the wood that builds itself” because the species naturally produces straight-grained pole-shaped trunks
• Mine timbers — historic Appalachian coal-mining use
• Ship and barge construction — high rot resistance underwater
• Modern engineered wood — increasingly used as an alternative to tropical hardwoods for outdoor furniture and decking (the European market in particular has growing demand)
• Honey — black locust flowers are a major nectar source; acacia honey sold in European markets is actually black locust honey (the European common name “false acacia” gives the honey its mislabeling)

See also

Auto-generated from this entry’s typed relations: frontmatter, grouped by relation type so the editorial signal isn’t flattened.

• Shares approach with: [[kudzu]] · [[wisteria]] · [[tamarind]] · [[sweet-pea]] · [[peanut]] · [[lentil]]
• Produces: [[firewood]]
• Member of: [[plants]]

Sources

• Wikipedia — Robinia pseudoacacia

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A plant entry in the 0mn1.one [[directory]].