Leaves broadly cuneate (lobed, lobes less than 1/2 blade lengths, 1-3 mm wide, rounded). Involucres 3.5-4(-5) × 2-4.5 mm. 2n = 18, 36. Flowering mid-late summer. Rocky sedimentary soils, high valleys, mountain slopes; 1500-3800 m; Calif., Colo., Idaho, Mont., Nev., Utah, Wash., Wyo. The relatively large heads of Artemisia arbuscula subsp. arbuscula suggest a relationship with A. cana; the extreme morphologic variability of this subspecies from east to west may be the result of hybridization with various subspecies within the A. cana complex.