Plants 20-30(-100) cm. Basal leaves: blades elliptic or lance-elliptic to lanceolate, 12-30 cm, margins entire, not ciliate, faces usually ± hirsutulous or scabrellous, sometimes glabrate; cauline leaves mostly smaller, narrower, distal-most usually petiolate, rarely sessile and clasping. Heads borne singly or 2-4+ in ± corymbiform arrays. Involucres turbinate to hemispheric, 18-25+ mm diam. Phyllaries 16-34, subequal, ± herbaceous, margins ciliate, faces glabrous or strigillose to hispidulous; outer 18-22(-30) mm (not or seldom surpassing discs). Ray florets 11-12; laminae (25-)35-50 mm (abaxially hirsutulous). Cypselae 9-10 mm, glabrous. 2n = 38.
Flowering Apr-Jun. Meadows, openings in pine, oak, or spruce-fir forests; 600-2200(-3000) m; Ariz., Colo., N.Mex., Utah.
At the northern margin of the range, glabrate plants with the general habit of Wyethia arizonica (introgressants with W. amplexicaulis) exhibit greater frost-hardiness (a characteristic of W. amplexicaulis) than do other members of the species.
General: Perennial, 20-100 cm tall; stems 1 to few, erect, branched from the base, hirsute-pubescent, becoming nearly glabrous with age; caudex rarely branched; taproot woody, stout, relatively large.
Leaves: Basal and cauline, alternate, firm, elliptic, lance- elliptic, or lanceolate, 12-30 cm long, 3-10 cm wide, the cauline blades much reduced, surfaces more-or-less hirsute, sometimes minutely scabrous or nearly glabrous, margins entire; basal blades petiolate, cauline blades usually petiolate, seldom sessile and clasping.
Flowers: Heads solitary or 2-3 in cyme- to corymb-like arrays; involucre hemispheric to saucerlike, mostly 6-12 mm long, 10-20 mm wide; phyllaries 12-18 or more, in 1-2 series, strigose, often spreading; ray flowers mostly 10-15, 8-20 mm long, yellow, the tips deeply 3-toothed; disk flowers 80-150 or more, yellow; flowers June-September.
Fruits: Achene, prism-shaped, 8-10 mm long, faintly 3-4 angled, glabrous; pappus absent.
Ecology: Open to wooded slopes, woodland openings; 2000-2900 m (6500-9500 ft); Apache, Coconino, Gila, Greenlee, Navajo, and Yavapai counties; southwestern U.S.
Notes: Balsamorhiza sagittata (arrowleaf balsamroot) is a perennial, mostly 20-40 cm tall, with long petiolate, rounded triangular basal leaves 5-25 cm long, 3-15 cm wide, the surfaces whitish, silvery, to gray-green; heads are usually solitary, borne on long peduncles; ray flowers are mostly 5-21, 2-4 cm long, yellow; disk flowers are numerous, yellow to orange. It occurs in open habitats, meadows, sagebrush, and forested communities at 900-2400 m (3000-8000 ft).
Editor: Springer et al. 2008
