Agoseris glauca var. dasycephala

(Torrey & A. Gray) Jepson
Man. Fl. Pl. Calif., 1005. 1925.
Common names: Arctic agoseris
IllustratedEndemic
Basionym: Troximon glaucum var. dasycephalum Torrey & A. Gray Fl. N. Amer. 2: 490. 1843
Synonyms: Agoseris altissima Rydberg Agoseris aspera (Rydberg) Rydberg Agoseris eisenhoweri B. Boivin Agoseris glauca subsp. aspera (Rydberg) Piper Agoseris glauca var. aspera (Rydberg) Cronquist Agoseris glauca var. pumila (Nuttall) Garrett Agoseris glauca subsp. scorzonerifolia (Schrader) Piper Agoseris glauca var. villosa (Rydberg) G. L. Wittrock Agoseris isomeris (Nuttall) Rydberg Agoseris lanulosa (Schrader) Greene Agoseris leontodon var. aspera Rydberg Agoseris leontodon var. pygmaea Rydberg Agoseris maculata Rydberg Agoseris pubescens Agoseris pumila Agoseris scorzonerifolia Agoseris turbinata Agoseris vestita Agoseris villosa
Treatment appears in FNA Volume 19. Treatment on page 326. Mentioned on page 327, 328, 329, 334.

Leaf blades: margins often undulate, usually entire, sometimes lobed, faces usually puberulent to densely villous, sometimes glabrous, rarely glaucous. Peduncles usually apically villous to lanate (glabrous in one phase), sometimes ± stipitate-glandular. Involucres obconic to hemispheric. Phyllaries often medially rosy purple and usually with some combination of purple-black spots, speckles, midstripes, or tips, rarely all green, margins ± undulate or reflexed, often hairy, faces usually villous to hirsuto-tomentose, sometimes glabrous, mostly stipitate-glandular; outer erect or spreading, usually adaxially villous, sometimes glabrous. Receptacles usually ± paleate. Cypselae usually glabrous, sometimes scabrous distally. 2n = 36.


Phenology: Flowering Jul–Aug.
Habitat: Moist to dry habitats, alpine meadows, montane forests, northern prairies, arctic tundra, in gravelly, rocky, and other coarse-textured soils
Elevation: 100–3600 m

Distribution

V19-496-distribution-map.gif

Alta., B.C., Man., N.W.T., Sask., Yukon, Colo., Idaho, Mont., N.Dak., Oreg., S.Dak., Utah, Wash., Wyo.

Discussion

Variety dasycephala occurs primarily at high elevations in the western cordillera, extending eastward onto the northern prairies, and disjunctively in the Canadian arctic (Caribou Hills). It is more readily distinguished from var. glauca southward, where the two varieties are ± elevationally separated. Difficulty in separating them occurs northward, where they are nearer each other and pockets of complete introgression occur, e.g., southeastern British Columbia and southwestern Alberta. Hybrids with Agoseris aurantiaca and A. parviflora also occur.

Variety dasycephala contains regional phases that exhibit a step-clinal distribution. The large number of synonyms reflects the variation. As circumscribed here, var. dasycephala encompasses most of what has been called Agoseris glauca var. agrestis (see discussion under var. glauca).

Selected References

None.

Lower Taxa

None.

Gary I. Baird +
(Torrey & A. Gray) Jepson +
Troximon glaucum var. dasycephalum +
Arctic agoseris +
Alta. +, B.C. +, Man. +, N.W.T. +, Sask. +, Yukon +, Colo. +, Idaho +, Mont. +, N.Dak. +, Oreg. +, S.Dak. +, Utah +, Wash. +  and Wyo. +
100–3600 m +
Moist to dry habitats, alpine meadows, montane forests, northern prairies, arctic tundra, in gravelly, rocky, and other coarse-textured soils +
Flowering Jul–Aug. +
Man. Fl. Pl. Calif., +
Illustrated +  and Endemic +
Agoseris altissima +, Agoseris aspera +, Agoseris eisenhoweri +, Agoseris glauca subsp. aspera +, Agoseris glauca var. aspera +, Agoseris glauca var. pumila +, Agoseris glauca subsp. scorzonerifolia +, Agoseris glauca var. villosa +, Agoseris isomeris +, Agoseris lanulosa +, Agoseris leontodon var. aspera +, Agoseris leontodon var. pygmaea +, Agoseris maculata +, Agoseris pubescens +, Agoseris pumila +, Agoseris scorzonerifolia +, Agoseris turbinata +, Agoseris vestita +  and Agoseris villosa +
Agoseris glauca var. dasycephala +
Agoseris glauca +
variety +