Artemisia borealis |
Artemisia spiciformis |
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boreal wormwood, field sagewort |
big sagebrush, snowfield sagebrush, spike sagebrush |
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Habit | Perennials, (6–)8–20(–40) cm (cespitose), mildly aromatic; taprooted, caudices branched. | Shrubs, 30–80 cm (widely branched, gray-tomentose), aromatic; root-sprouting. | ||||
Stems | (1–)2–5, gray-green, tomentose. |
relatively numerous, brown or grayish green. |
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Leaves | persistent, basal rosettes persistent, gray-green to white; blades ovate, 2–4 × 0.5–1 cm, 2–3-pinnately or -ternately lobed, lobes linear to narrowly oblong, apices acute, faces moderately to densely sericeous. |
± deciduous (by late summer, turning yellow); blades lanceolate, oblanceolate, or cuneate, 2.5–5.5 × 0.8–1.2+ cm, entire or irregularly 3–6-lobed (lobes to 1/3 blade lengths, 1.5+ mm wide, rounded or acute; leaves of flowering stems usually smaller, entire), faces ± sericeous or tomentose. |
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Involucres | hemispheric, 3–4 × 3.5–4 mm. |
ovoid or lanceoloid, (2.5–)4–6(–7) mm. |
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Florets | pistillate 8–10; functionally staminate 15–30; corollas (or lobes) yellow-orange or deep red, 2.2–3.5. |
8–18(–27); corollas 2.5–3.5, glabrous. |
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Phyllaries | (obscurely scarious) densely tomentose-villous. |
lanceolate, sparsely to densely hairy. |
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Heads | (proximal sessile, distal pedunculate) in (leafy) spiciform arrays 4–9(–12) × (0.5–)1–5 cm. |
(erect) in (leafy) paniculiform arrays 8–15(–25) × 0.5–3(–4) cm. |
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Cypselae | oblong-lanceoloid, somewhat compressed, 0.4–1 mm, faintly nerved, glabrous. |
1–1.5 mm, glabrous or resinous. |
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2n | = 18, 36, 54, 72. |
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Artemisia borealis |
Artemisia spiciformis |
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Phenology | Flowering mid summer–fall. | |||||
Habitat | Moist open slopes, rocky meadows, streamsides, woodlands, late-lying snowfields | |||||
Elevation | 2100–3700 m (6900–12100 ft) | |||||
Distribution |
AK; CA; CO; ID; MT; UT; WA; WY; AB; BC; NT; NU; SK; YT; especially at high elevations and northern latitudes; Eurasia
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CA; CO; ID; NV; OR; UT; WA; WY
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Discussion | Subspecies 2 (2 in the flora). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Often confused with Artemisia rothrockii, A. spiciformis has been recognized only recently as a widespread, high-elevation sagebrush of late-lying snowfields. Molecular analysis has not yet determined the degree to which this species intergrades with A. cana subsp. viscidula and A. tridentata subsp. vaseyana, the presumed parents of this putative hybrid. Because snow-field sagebrush produces fertile seeds and forms a stable community type, it is treated here as a distinct species. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 19, p. 505. | FNA vol. 19, p. 515. | ||||
Parent taxa | Asteraceae > tribe Anthemideae > Artemisia > subg. Drancunculus | Asteraceae > tribe Anthemideae > Artemisia > subg. Tridentatae | ||||
Sibling taxa | ||||||
Subordinate taxa | ||||||
Synonyms | A. campestris subsp. borealis | A. tridentata subsp. spiciformis, Seriphidium spiciforme | ||||
Name authority | Pallas: Reise Russ. Reich. 3: 755. (1776) | Osterhout: Bull. Torrey Bot. Club 27: 507. (1900) | ||||
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