View a key to the hawthorns of the Pacific Coast (from Alaska to California), and species notes, by Jim Phipps.

General:
Medium to tall shrub 1-7 m tall, with stout, straight thorns 1-2 (3) cm long; bark grey or brownish, rough and scaly.

Leaves:
Alternate, deciduous, egg-shaped to oval, 3-6 cm long, irregularly toothed, the top end often with 5 to 9 shallow lobes, somewhat thick and leathery, dark green above, paler below, nearly smooth to hairy.

Flowers:
Inflorescences short, terminal or axillary clusters; flowers several to many, stalked, 1-1.5 cm across; corollas white, the petals 5, nearly circular, 4-7 mm long; calyces 5-lobed, the lobes triangular, somewhat long-hairy toward the tip; ovaries inferior, smooth to short-curly-hairy, the styles usually 5; stamens 10 to 20.

Fruits:
Berry-like pomes (like miniature apples), globe- to egg-shaped, about 1 cm long, blackish-purple, smooth; stones (nutlets) 2 to 5, 1-seeded.

Notes:
Two varieties occur in BC:

1. Flowers mostly with 10 stamens; ovaries often hairy; leaves often weakly lobed above the middle as well as saw-toothed; plants from largely east of the Coast-Cascade Mtns., the common variety................. var. douglasii

1. Flowers mostly with 20 stamens; ovaries usually smooth; leaves merely 1- to 2-times saw-toothed; plants from west of the Cascade Mtns........................ var. suksdorfii Sarg.

Source:  The Illustrated Flora of British Columbia

Synonyms and Alternate Names:
Crataegus suksdorfii (Sarg.) Kruschke