Sitka mountain ash

Leaflets: l/w ratio 2.2–3.1, margins toothed apically, serrate for more than 1/2 their length, serrations fine to coarse, sometimes doubly serrate. Flowers: petals white, pink or white in bud, claw glabrous or villous; styles 1.5–2.2(–3) mm. 2n = 68.

Flowering spring; fruiting fall. Open conifer woods, forest edges, mountain slopes, meadows, shores of lakes and streams; 0–2400 m; Alta., B.C., Yukon; Alaska, Calif., Idaho, Mont., Oreg., Wash.