Scabland sagebrush

Artemisia trifida Nuttall var. rigida Nuttall, Trans. Amer. Philos. Soc., n. s. 7: 398. 1841; Seriphidium rigidum (Nuttall) W. A. Weber

Shrubs, 20–40 cm (branches widely spreading), mildly aromatic; root-sprouting (caudices stout). Stems gray (coarse, brittle), hairy (bark gray, exfoliating). Leaves deciduous, silver-gray (rigid); blades broadly spatulate, 1.5–4 × 0.5–0.7 cm (bases narrow), 3-lobed (lobes ¹/2+ blade lengths, ca. 1 mm wide), faces densely hairy. Heads borne singly or (in glomerules) in (densely leafy) spiciform or paniculiform arrays 2–20 × 2 cm. Involucres narrowly campanulate, 4–5 × 2.5–3.5 mm. Phyllaries elliptic (acute to obtuse), densely canescent. Florets 4–8; corollas yellowish red to red, 2–2.8 mm (style branches oblong, truncate, exsert). Cypselae (4–5-ribbed) 1–1.5 mm, glabrous. 2n = 18, 36.

Flowering mid summer–early fall. Dry rocky scablands, volcanic plains; 1500–1800 m; Idaho, Mont., Oreg., Wash.

Artemisia rigida is an important successional species following fires because the plants form new shoots from the underground caudices. This characteristic aligns the species with other ‘sprouters’ in the subgenus, namely A. cana, A. tripartita, and A. arbuscula.