Robinia pseudoacacia earned the name False Acacia for the resemblance of its pinnately compound leaves and hanging flower clusters to true acacias, but there is nothing false about the impact of a mature specimen in full bloom. From April through June, the tree drapes itself in 5-inch clusters of white, intensely fragrant pea-like flowers that pull in bees with remarkable efficiency. Growing 30 to 50 feet tall and 20 to 35 feet wide, the tree develops deeply furrowed, ridged gray-brown bark of real character. Blue-green compound leaves with up to 23 leaflets rustle easily in the wind and turn yellow in autumn before flattened brown seed pods persist well into winter.

This is a tree of difficult sites: compacted soils, dry banks, abandoned lots, clay, and depleted ground where it fixes nitrogen and stabilizes slopes. It transplants well and tolerates moderate salt. The honest caveat is that black locust spreads aggressively by root suckers, can become invasive in the Midwest, and its brittle branches shed readily in storms. Locust borer is a serious and often fatal pest. For naturalistic woodland edges, reclamation plantings, or truly tough urban conditions where a canopy tree is needed, it delivers. For the home garden, the maintenance demands are considerable, and native alternatives deserve consideration first.