UW Burke Herbarium species comparison

Leaves mostly 5-foliate, the leaflets broadly oblong to ovate, short acuminate, 6-12 cm. long, sharply serrate, bright green and glabrous above, grayish-woolly beneath.

Inflorescence a flat-topped panicle;

calyx woolly, the 5 segments reflexed, lanceolate, 8-12 mm. long;

petals 5, white to reddish tinged, oval-obovate, 10-15 mm. long;

stamens 100 or more;

pistils many, the style slender, glabrous.

Drupelets coherent, and with the fleshy receptacle forming a nearly globose blackberry 1.5 cm. thick.