Artemisia arbuscula |
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black sagebrush, dwarf sagebrush, little sagebrush, low sagebrush |
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Habit | Shrubs, 10–30(–50) cm, aromatic; root-sprouting. | ||||||||
Stems | gray-green to brown, glabrate (diffusely branched from bases, brittle). |
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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). |
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Involucres | campanulate or globose-ovoid, (1.5–)2–4(–5) × 1.5–4.5 mm. |
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Florets | 4–6(–10); corollas 1.5–2 mm, glabrous. |
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Phyllaries | (margins green) ovate (outer) to oblong, pubescent or tomentose. |
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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). |
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Cypselae | (light brown) 0.7–0.8 mm, resinous. |
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Artemisia arbuscula |
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Distribution |
CA; CO; ID; MT; NV; OR; UT; WA; 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. | ||||||||
Parent taxa | Asteraceae > tribe Anthemideae > Artemisia > subg. Tridentatae | ||||||||
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Synonyms | A. tridentata subsp. arbuscula, A. tridentata var. arbuscula, Seriphidium arbusculum | ||||||||
Name authority | Nuttall: Trans. Amer. Philos. Soc., n. s. 7: 398. (1841) | ||||||||
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