Artemisia arbuscula |
Artemisia scopulorum |
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black sagebrush, dwarf sagebrush, little sagebrush, low sagebrush |
alpine sagebrush, dwarf sagebrush |
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Habit | Shrubs, 10–30(–50) cm, aromatic; root-sprouting. | Perennials, 10–25 cm (cespitose), mildly aromatic (caudices relatively slender). | ||||||||
Stems | gray-green to brown, glabrate (diffusely branched from bases, brittle). |
gray-green, glabrate. |
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Leaves | (vegetative stems) persistent, gray-green; blades broadly to narrowly cuneate, 3–10 × 2–5 mm, lobed (lobes 3, oblong-linear, to 1/3 blade lengths, mostly 1–3 mm wide, flat, obtuse, laterals sometimes 2–3-fid; leaves on flowering stems deciduous, blades narrowly cuneate, deeply 3-lobed), faces densely hairy (not sticky resinous). |
persistent, gray-green; blades (basal) oblanceolate, 2–7 × 0.1 cm, 2-pinnately lobed (lobes linear or oblanceolate; cauline blades smaller, 1–2-pinnate or entire), faces silky-canescent. |
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Involucres | campanulate or globose-ovoid, (1.5–)2–4(–5) × 1.5–4.5 mm. |
broadly globose or subglobose, 4 × 4–7 mm. |
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Florets | 4–6(–10); corollas 1.5–2 mm, glabrous. |
pistillate 6–13; bisexual 15–30; corollas 1.5–2.5 mm, hairy (at least on lobes). |
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Phyllaries | (margins green) ovate (outer) to oblong, pubescent or tomentose. |
green (margins black or dark brown), densely villous. |
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Heads | usually borne singly, rarely (1–4, erect, mostly sessile, in pedunculate clusters) in spiciform or paniculiform arrays 2–9 × 0.5–2 cm (branches slender). |
(5–22) in spiciform arrays 5–9 × 1–1.5 cm. |
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Cypselae | (light brown) 0.7–0.8 mm, resinous. |
0.8–1 mm, glabrous. |
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2n | = 18. |
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Artemisia arbuscula |
Artemisia scopulorum |
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Phenology | Flowering mid–late summer. | |||||||||
Habitat | Alpine meadows, protected areas, bases of rocks | |||||||||
Elevation | 3100–4200 m (10200–13800 ft) | |||||||||
Distribution |
CA; CO; ID; MT; NV; OR; UT; WA; WY
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CO; MT; NM; NV; UT; WY
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Discussion | Subspecies 3 (3 in the flora). Artemisia arbuscula is one of the more perplexing species in the Tridentatae complex. Anatomic and morphologic characteristics suggest multiple hybrid origins for the subspecies. Deciduous leaves of flowering stems in plants that otherwise have persistent leaves suggest a hybrid origin involving plants of the A. tridentata and A. cana lineages. In most instances, populations of A. arbuscula appear to be reproductively stable. The disposition of Artemisia arbuscula subsp. longicaulis Winward & McArthur (with 2n = 54) has not been determined. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 19, p. 511. | FNA vol. 19, p. 520. | ||||||||
Parent taxa | Asteraceae > tribe Anthemideae > Artemisia > subg. Tridentatae | Asteraceae > tribe Anthemideae > Artemisia > subg. Absinthium | ||||||||
Sibling taxa | ||||||||||
Subordinate taxa | ||||||||||
Synonyms | A. tridentata subsp. arbuscula, A. tridentata var. arbuscula, Seriphidium arbusculum | |||||||||
Name authority | Nuttall: Trans. Amer. Philos. Soc., n. s. 7: 398. (1841) | A. Gray: Proc. Acad. Nat. Sci. Philadelphia 15: 66. (1863) | ||||||||
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