Draba norvegica

Draba norvegica, the Norwegian draba or rock whitlow-grass, is a small, cushion-forming perennial herb of the Brassicaceae with a circumpolar arctic-alpine distribution extending across Greenland, Iceland, Scandinavia, the British Isles, arctic Russia and northern North America from Alaska east to Labrador and Newfoundland. It grows on calcareous cliffs, exposed rock ledges, scree, gravelly tundra and stable moraines from subalpine to high arctic elevations, typically reaching only 3-15 cm tall from a slender, branched caudex topped by tight rosettes of leaves. The basal leaves are oblanceolate to narrowly elliptic, 5-15 mm long, entire or with one or two faint teeth, ciliate on the margins and densely clothed with simple, forked and stellate hairs. The leafless or one- to three-leaved flowering scapes bear a short, congested raceme of small white four-petalled cruciform flowers 3-5 mm across, which elongates somewhat in fruit. The fruits are ovoid to oblong-elliptic, slightly twisted, glabrous to sparsely hairy siliques 4-9 mm long containing minute pale brown seeds. The species is polyploid and morphologically variable.