Artemisia palmeri |
Artemisia tridentata |
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Palmer sagewort, San Diego sagewort |
big sagebrush, blue sagebrush, common sagebrush, mountain sagebrush, sagebrush |
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Habit | Subshrubs, 100–350 cm, mildly aromatic. | Shrubs, 40–200(–300) cm (herbage gray-haired), aromatic; not root-sprouting (trunks relatively thick). | ||||||||||||
Stems | usually 1–15, erect, brown, simple (wandlike, brittle, bases woody), glabrous. |
gray-brown, glabrate (bark gray, exfoliating in strips). |
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Leaves | cauline (petiolate), bicolor (gray-green and dark green); blades broadly lanceolate, 3.5–12(–15) × 0.2–10 cm, relatively deeply and coarsely pinnately lobed (lobes 3–7+), faces canescent (abaxial) or glabrous or sparsely hairy (adaxial). |
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 | globose, 2.5–3.5 × 2–5 mm. |
lanceolate, (1–)1.5–4 × 1–3 mm. |
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Florets | pistillate 0; bisexual 8–30; corollas pale yellow, 1.5–2.2 mm, resinous-glandular (style branches exsert, truncate, erose). |
3–8; corollas 1.5–2.5 mm, glabrous. |
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Phyllaries | (pale green to stramineous) broadly ovate, glabrous or sparsely hairy (receptacles paleate). |
oblanceolate to widely obovate, densely tomentose. |
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Heads | (erect or nodding, peduncles relatively slender) in open, paniculiform arrays, 15–40 × 3–10 cm (widely branched). |
(usually erect, on slender peduncles) in paniculiform arrays 5–30 × 1–6 cm. |
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Cypselae | (light brown, shiny) ellipsoid, 1–1.2 mm, (4-angled), glabrous or glandular. |
1–2 mm, hairy or glabrous, glandular. |
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2n | = 18. |
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Artemisia palmeri |
Artemisia tridentata |
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Phenology | Flowering early–mid summer. | |||||||||||||
Habitat | Ravines, coastal areas, sandy soils | |||||||||||||
Elevation | 100–300 m (300–1000 ft) | |||||||||||||
Distribution |
CA; Mexico (Baja California)
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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 | Of conservation concern. Artemisia palmeri is known only from drainages near the coast, from northeast of San Diego to just south of Ensenada. Most of its habitat has been destroyed by urban development. It is of particular interest because of its paleate receptacles, an anomalous trait that confounds our understanding of its evolutionary relationship to other species of Artemisia. (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. | FNA vol. 19, p. 516. | ||||||||||||
Parent taxa | ||||||||||||||
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Synonyms | Artemisiastrum palmeri | Seriphidium tridentatum | ||||||||||||
Name authority | A. Gray: Proc. Amer. Acad. Arts 11: 79. (1876) | Nuttall: Trans. Amer. Philos. Soc., n. s. 7: 398. (1841) | ||||||||||||
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