Erigeron humilis, R. C. Graham

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1976, Flora Europaea. Volume 4. Plantaginaceae to Compositae (and Rubiaceae), Cambridge University Press : 119

15. E. humilis R. C. Graham , Edinb. New Philos. Jour. 6: 175 (1829).

Perennial up to 12 cm but usually much less, with flowering stems scarcely emerging from the basal leaves. Basal leaves l-5~3-5xO-3-O-6 cm, spathulate, narrowly petiolate, rounded at the apex, ciliate, sparsely pubescent when young. Cauline leaves 1-4. Upper part of flowering stem and involucre with dense, long, patent, deep purple hairs. Capitula solitary; involucral bracts deep purple. Florets dimorphic; ligules white to purplish. 2« = 36. Damp, stony hillsides and tundra. Arctic and subarctic Europe, eastwards to N. W. Finland. Fe Is No Sb Su.

While this species is usually quite distinct from 14 when fresh, the contraction to the cell walls of the pigment in the involucral hairs on drying can lead to misidentification. The base of the involucre is said to be cuneate (truncate in 14), but this character is unreliable. Sterile triploid hybrids between 14 and 15 are common in N. Norway and Sweden; they are most readily recognized by their failure to produce pollen.