Distribution: Occurring east of the Cascades crest in eastern Washington; British Columbia to Oregon and Nevada, east to Alberta, Montana, Wyoming, and Colorado.
Habitat: Canyons and hillsides, grasslands, ponderosa pine and Douglas-fir forest openings and edge.
Flowers: May-July
Origin: Native
Growth Duration: Perennial
Conservation Status: Not of concern
Spreading to erect shrub 0.5-2 m. tall, the branches angled, usually glabrous.
Leaves alternate, petiolate, the blades ovate to cordate, 3-5 lobed, the lobes bi-serrate, 4-7 cm. long and broad, dark green and glabrous above and paler below, with stellate hairs.
Flowers rather numerous in terminal clusters; calyx hemispheric, with stellate hairs, the 5 lobes ovate-lanceolate, 3 mm. long, somewhat reflexed; petals 5, white, sub-orbicular, 4 mm. long, spreading; stamens about 30, equaling the petals; pistils 2, attached to each other at least half way, strongly stellate-haired.
Fruit a glabrous follicle, 7-11 mm. long, swollen.
PNW Herbaria: Specimen records of Physocarpus malvaceus in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Physocarpus malvaceus checklist entry
OregonFlora: Physocarpus malvaceus information
E-Flora BC: Physocarpus malvaceus atlas page
CalPhotos: Physocarpus malvaceus photos