General:
Medium to tall shrub, 1-4 m tall, much-branched, very thorny with spine-tipped spur shoots, sometimes suckering to form dense thickets; twigs blackish, sometimes hairy when young.

Leaves:
Alternate, deciduous, oval to egg-shaped, 2-4 cm long, finely saw-toothed, blunt at the tip, hairy on both surfaces or on the veins beneath but becoming smooth, short-stalked, the stalks usually without glands.

Flowers:
Inflorescence a cluster of stalked flowers, the flowers single at each of the several crowded nodes of a short spur-shoot that was formed the previous year; corollas white, bowl-shaped, 1-2 cm across, the petals 5, oblong-egg-shaped, 5-7 mm long; calyces 5-lobed; ovaries superior.

Fruits:
Fleshy drupes with a large wrinkled stone (prunes), nearly globe-shaped, 10-15 mm long, on stalks shorter than 1 cm, bluish-purple to black, with whitish bloom; seeds 1.

Source:  The Illustrated Flora of British Columbia

If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.

Illustration Source:  The Illustrated Flora of British Columbia