Robinia pseudoacacia

Common Names

Black Locust, False Acacia, Yellow Locust, White Locust, Common Locust, Green Locust, Locust

Summary

Black locust, Robinia pseudoacacia, is a fast-growing deciduous tree native to the Appalachian Mountains in the eastern United States, now widely planted and naturalized in temperate regions, it typically reaches about 40–70 ft in height with an irregular crown and a trunk up to 2–4 ft in diameter, and features deeply furrowed bark and zigzag twigs with paired thorns on young growth, leaves are pinnately compound with 7–19 dull green leaflets, in late spring to early summer dense racemes of creamy white, highly fragrant flowers appear, followed by 2–4 inch flat seed pods, prefers full sun and well-drained soils, tolerates drought and a wide range of soil types, and is valued for erosion control, nitrogen fixation that improves soil fertility, and wood for fencing, posts, and timber, nectar from flowers supports bees and honey production, however, it forms dense thickets via root suckers, is often invasive outside native ranges, and management may include removing suckers and cautious planting away from infrastructure to minimize conflicts with landscapes

Lifecycle

Perennial

Height

480-960 inches

Spread

20-30 feet

Hardiness Zones

Zones 4-8

Sunlight Requirements

Ideally Full Sun, tolerates Partial Sun or Partial Shade

Soil Type

Well-drained soils, particularly loams or sandy loams

Soil Drainage

Well-drained

Soil pH

Tolerates a wide pH range (approximately 4.6-8.2) with a preferred pH around 6.0–7.0

Bloom Color

White to cream; occasionally yellowish or pink-tinged

Bloom Time

Spring to Summer

Foliage Color

Green to blue-green

Fall Foliage Color

Yellow

Leaf Lifecycle

Deciduous

Growth Rate

About 2–3 feet per year when young.

Seasons of Interest

Spring, Summer, Fall, Winter

Propagation Methods

Seeds, Root cuttings, Root suckers, Layering

Attracts Wildlife

Attracts bees, hummingbirds, butterflies, other pollinators, and birds