Erigeron allocotus S.F. Blake
Family: Asteraceae
Big Horn Fleabane
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Perennials, 10-18 cm; taprooted, caudices multicipital or branched. Stems erect to ascending (branched, brittle), hispido-hirsute (hairs brittle), minutely glandular. Leaves basal (often not persistent) and cauline; blades spatulate 15-30 × 1.5-4 mm, cauline gradually reduced distally (reduced to bracts on peduncles), margins usually 3-lobed (lobes linear to oblong-oblanceolate, about as wide as central portion of blades), sometimes 2-ternate or (cauline) entire, faces sparsely hispido-hirsute, minutely glandular. Heads usually 2-4. Involucres 4-5 × 6-9 mm. Phyllaries in 2-3 series, glabrous or sometimes sparsely hispid, densely minutely glandular. Ray florets 20-40; corollas white to bluish, sometimes drying pink, 3-6 mm, laminae not coiling or reflexing. Disc corollas 2.5-3.5 mm. Cypselae 2-2.3 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of 12-20 bristles.

Flowering May-Aug. Dry, calcareous sites on cliff faces, ledges, talus slopes, ridgetops, rock outcrops, barren redbeds, sometimes with Utah juniper, mountain mahogany, or sagebrush; 1300-2300 m; Mont., Wyo.

The brittle, hispid vestiture, and multiple small heads (more than one per stem) with short rays of Erigeron allocotus are unusual among its putative relatives with 3-parted leaves.