Bristly or pink-flowered locust is an invasive deciduous small tree species (less than three meters tall) native to the southeastern United States. It is widely cultivated but escapes into nearby disturbed open woods and thickets, and is now found in most US states and some Canadian provinces (Ontario and British Columbia) (USDA 2010). In British Columbia, it has been planted in reclaimed mine tailing dumps around Trail and is now well established in the area, with a large infestation in Kokanee Creek Provincial Park.

This is a sun-loving, shade tolerant member of the pea family (Fabaceae), with alternate, pinnately-compound leaves with 9-13 entire leaflets, 7-9 inches long. It has very bristly stems (soft bristles) with paired thorns at the nodes. The light pink to rose-coloured (sometimes lavender) flowers are showy and fragrant, and appear in late spring and early summer. Fruits are approximately 8 cm long, and densely hispid. It can spread clonally via stolons to form thickets. The single specimen of this species in the UBC Herbarium is from Burnaby, collected by Frank Lomer in 2008.

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