Arabis pycnocarpa M. Hopkins
blushing rock-cress
Brassicaceae (Mustard family)

Introduction to Vascular Plants


© Curtis Bjork     (Photo ID #46920)


E-Flora BC Static Map

Distribution of Arabis pycnocarpa
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Arabis pycnocarpa var. pycnocarpa

Species Information

Biennial or short-lived perennial herb from a simple stem-base; stems usually simple, 15-100 cm tall, strongly stiff-hairy at the base, usually glabrous above.
Basal leaves oblanceolate, 2-8 cm long, 1-1.5 cm wide, narrowed to a fringed, winged stalk, often purplish beneath, glabrous to hairy, remotely toothed; stem leaves broadly egg-shaped, 2-10 cm long, 1-3 cm wide, broadly unstalked, usually ear-like at the bases and clasping.
Racemes few to many flowered; petals 4-9 mm long, white to cream or pale pink; outer sepals bulging on one side at the base.
Siliques, erect, tightly appressed to the axis of the inflorescence or angled slightly outward, 4-8 cm long, 0.75-1.5 mm wide; seeds in 1 row, 1.5 mm long, with narrow wings.
All of our BC material is referable to the var. pycnocarpa (Hopkins) Roll., except for a single collection of the European var. hirsuta, from Glacier National Park.. The two varieties may be separated as follows:

1. Plants perennials; siliques beakless.......................... var. hirsuta

1. Plants biennials or short-lived perennials; siliques with a beak 0.5-1.25 mm long........................... var. pycnocarpa (Hopkins) Roll.

SourceThe Illustrated Flora of British Columbia

Habitat and Range

Moist to mesic meadows, gravel bars, open woods, rock outcrops and waste places in the lowland and montane zones; var. hirsuta known in BC only from Glacier National Park; var. pycnocarpa common throughout BC east of the Coast-Cascade Mountains; circumpolar, S to CA, NM and GA; Eurasia.

SourceThe Illustrated Flora of British Columbia