Artemisia campestris |
Artemisia tridentata |
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beach wormwood, field sagewort, field wormwood, northern wormwood, Pacific sagewort, sand wormwood |
big sagebrush, blue sagebrush, common sagebrush, mountain sagebrush, sagebrush |
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Habit | Biennials or perennials, (10–)30–80(–150) cm, faintly aromatic; taprooted, caudices branched. | Shrubs, 40–200(–300) cm (herbage gray-haired), aromatic; not root-sprouting (trunks relatively thick). | ||||||||||||||||||||
Stems | usually 1–5, turning reddish brown, (often ribbed) tomentose or glabrous. |
gray-brown, glabrate (bark gray, exfoliating in strips). |
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Leaves | persistent or deciduous, mostly basal; basal blades 4–12 cm; cauline gradually reduced, 2–4 × 0.5–1.5 cm, 2–3-pinnately lobed, lobes linear to narrowly oblong, apices acute, faces densely to sparsely white-pubescent. |
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. |
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Involucres | broadly turbinate, 2.5–3(–5) × 2–3.5(–7) mm. |
lanceolate, (1–)1.5–4 × 1–3 mm. |
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Florets | pistillate 5–20; functionally staminate 12–30; corollas pale yellow, sparsely hairy or glabrous. |
3–8; corollas 1.5–2.5 mm, glabrous. |
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Phyllaries | (margins scarious) glabrous or villous-tomentose. |
oblanceolate to widely obovate, densely tomentose. |
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Heads | (pedunculate) in (mostly leafless) paniculiform arrays. |
(usually erect, on slender peduncles) in paniculiform arrays 5–30 × 1–6 cm. |
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Cypselae | oblong-lanceoloid, somewhat compressed, 0.8–1 mm, faintly nerved, glabrous. |
1–2 mm, hairy or glabrous, glandular. |
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Artemisia campestris |
Artemisia tridentata |
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Distribution |
AK; AR; AZ; CA; CO; CT; FL; IA; ID; IL; IN; KS; MA; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TX; UT; VT; WA; WI; WY; AB; BC; MB; NB; NU; ON; QC; SK; especially mountains and high latitudes; Eurasia
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AZ; CA; CO; ID; MT; ND; NE; NM; NV; OR; SD; UT; WA; WY; AB; BC; nw Mexico
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Discussion | Subspecies ca. 7 (3 in the flora). Artemisia campestris varies; each morphologic form grades into another. The present circumscription is conservative in that only three subspecies are recognized; the subspecies usually can be separated geographically as well as morphologically. Populations in western North America consist primarily of subsp. pacifica; east of the continental divide, plants are assigned to subsp. canadensis in northern latitudes and to subsp. caudata in southern latitudes. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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.) |
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Key |
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Source | FNA vol. 19, p. 506. | FNA vol. 19, p. 516. | ||||||||||||||||||||
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Synonyms | Seriphidium tridentatum | |||||||||||||||||||||
Name authority | Linnaeus: Sp. Pl. 2: 846. (1753) | Nuttall: Trans. Amer. Philos. Soc., n. s. 7: 398. (1841) | ||||||||||||||||||||
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