Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to southern California, east to the Rocky Mountains.
Habitat: Thickets, forest edge and openings, fields, and hillsides from low to middle elevations.
Conservation Status: Not of concern
Well-armed, deciduous perennial with erect to arching, glaucous stems, 1-3 m. long, the prickles numerous, stout, hooked, up to 6 mm. long.
Leaf blades trifoliate, greenish and glabrous above and white-woolly beneath, the leaflets ovate-lanceolate, 1.5-8 cm. long, irregularly doubly-serrate, or shallowly lobed and doubly-serrate.
Flowers 2-7 in an umbel-like raceme, the pedicels woolly and prickly; calyx wooly and glandular, the 5 segments narrowly lanceolate and pointed, reflexed; petals 5, white, spatulate, shorter than the sepals; stamens 70-100, glabrous; pistils numerous.
Drupelets coherent, coming free from the receptacle, reddish-purple to black, the fruit up to 12 mm. broad.