Artemisia tridentata |
Artemisia aleutica |
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big sagebrush, blue sagebrush, common sagebrush, mountain sagebrush, sagebrush |
Aleutian wormwood |
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Habit | Shrubs, 40–200(–300) cm (herbage gray-haired), aromatic; not root-sprouting (trunks relatively thick). | Perennials, 5–10 cm (cespitose), mildly aromatic; caudices branched. | ||||||||||||
Stems | gray-brown, glabrate (bark gray, exfoliating in strips). |
usually 1, reddish brown to gray, tomentose to glabrate. |
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Leaves | persistent, gray-green; blades usually cuneate, (0.4–)0.5–3.5 × 0.1–0.7 cm, 3-lobed (lobes to 1/3 blade lengths, 1.5+ mm wide, rounded), faces densely hairy. |
persistent, mostly basal, gray-green; (petioles often expanded) blades (at least proximal) obovate, 1.5–5 × 0.5–1 cm, 2-palmately lobed, lobes relatively narrow, apices acute, faces densely white-villous (brownish in age); cauline smaller, distally 1-ternate. |
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Involucres | lanceolate, (1–)1.5–4 × 1–3 mm. |
hemispheric or globose, (2–)5–7 × (2–)6–8 mm. |
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Florets | 3–8; corollas 1.5–2.5 mm, glabrous. |
pistillate 4–6; functionally staminate 15–30; corollas purplish red, 1.5–2 mm, hairy. |
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Phyllaries | oblanceolate to widely obovate, densely tomentose. |
villous. |
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Heads | (usually erect, on slender peduncles) in paniculiform arrays 5–30 × 1–6 cm. |
(sessile or peduncles 2–15 mm) in racemiform or spiciform arrays, 1.5–3 × 0.5–1 cm. |
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Cypselae | 1–2 mm, hairy or glabrous, glandular. |
oblong, ca. 1 mm, faintly nerved, glabrous. |
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Artemisia tridentata |
Artemisia aleutica |
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Phenology | Flowering mid–late summer. | |||||||||||||
Habitat | Open areas, fellfield tundra | |||||||||||||
Elevation | 0–100 m (0–300 ft) | |||||||||||||
Distribution |
AZ; CA; CO; ID; MT; ND; NE; NM; NV; OR; SD; UT; WA; WY; AB; BC; nw Mexico
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AK |
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Discussion | Subspecies 4 (4 in the flora). Artemisia tridentata has undergone considerable taxonomic revision in the past century and circumscription of subspecies remains a topic of considerable controversy. Workers in the field should be aware of the morphologic variation within the subspecies across the range of the species (i.e., approximately from the Sierra Nevada in the west to the plains of the Rocky Mountains in the east). Because rangeland managers and conservationists can often identify local morphologic and chemical races based on grazing or habitat preferences of wildlife and domestic animals, some impetus exists to further subdivide the subspecies within A. tridentata at the varietal level. This treatment of the species complex remains conservative in light of the need for further study. As to chemical differences among the subspecies, aroma is often used to distinguish subspecies in the field. Volatile resins in the plants are strongly aromatic and, when crushed, leaves have very distinctive (although not easily described) aromas. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Of conservation concern. Artemisia aleutica is known only from the western Aleutian Islands. It is morphologically similar to A. borealis, and the relationships of these species complexes warrant further study. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 19, p. 516. | FNA vol. 19, p. 505. | ||||||||||||
Parent taxa | Asteraceae > tribe Anthemideae > Artemisia > subg. Tridentatae | Asteraceae > tribe Anthemideae > Artemisia > subg. Drancunculus | ||||||||||||
Sibling taxa | ||||||||||||||
Subordinate taxa | ||||||||||||||
Synonyms | Seriphidium tridentatum | |||||||||||||
Name authority | Nuttall: Trans. Amer. Philos. Soc., n. s. 7: 398. (1841) | Hultén: Bot. Not. 1939: 829, fig. 2. (1939) | ||||||||||||
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