Artemisia bigelovii |
Artemisia pedatifida |
|
---|---|---|
Bigelow sage, Bigelow sagebrush, Bigelow sagewort, Bigelow's sage |
birdfoot sagebrush, Matted sagewort |
|
Habit | Shrubs, 20–40(–60) cm (branched from bases, rounded), mildly aromatic; not root-sprouting. | Perennials or subshrubs, 5–15 cm (cespitose), aromatic. |
Stems | silvery, canescent (bark gray-brown). |
(5–20), gray-green, glabrescent. |
Leaves | persistent, light gray-green; blades narrowly cuneate, 0.5–3 × 0.2–0.5 cm, entire or 3(–5)-lobed (lobes 1.5–2 mm, less than 1/3 blade lengths, acute), faces silvery canescent. |
persistent, gray-green, mostly basal; proximal blades reduced, mostly less than 1 cm, lobed or entire; distal blades 1–2 × 0.5–0.8 cm, 1–2-ternately lobed, lobes 1–2 mm wide, apices acute, faces densely tomentose. |
Involucres | globose, 2–3 × 1.5–2.5 mm. |
globose, 3–4 × 3–4 mm. |
Florets | pistillate 0–2 (raylike, laminae to 1 mm); bisexual 1–3; corollas 1–1.5 mm (style branches of ray florets elongate, exsert, epapillate, tips acute; of disc florets, short, truncate, papillate). |
pistillate 4–7; functionally staminate 5–9; corollas yellow, usually red-tinged, 2–3 mm, glabrous. |
Phyllaries | (8–15) ovate, canescent or tomentose. |
(margins scarious, obscured) white-tomentose. |
Heads | (usually nodding) in arrays 6–25 × 1–4 cm (branches erect, somewhat curved). |
(mostly 6–15, 1 or 3–4 on lateral branches; mostly erect, sessile or pedunculate) in racemiform-paniculiform arrays, 5–8 × 0.5–0.8 cm. |
Cypselae | (ellipsoid, 5-ribbed) 0.8–1 mm, glabrous. |
(brown) ellipsoid (angled), 0.8–1 mm, (sometimes with white ribs) glabrous. |
2n | = 18, 36, 72. |
|
Artemisia bigelovii |
Artemisia pedatifida |
|
Phenology | Flowering early summer–late fall. | Flowering early spring–mid summer. |
Habitat | Deserts, sandy or alkaline soils, rock outcrops | High plains, grasslands |
Elevation | 1000–2500 m (3300–8200 ft) | 1600–1800 m (5200–5900 ft) |
Distribution |
AZ; CA; CO; NM; NV; TX; UT
|
CO; ID; MT; WY
|
Discussion | Artemisia bigelovii of the southwestern deserts is easily confused in the field with A. tridentata, even though it is well distinguished ecologically and morphologically. Systematic placement within subg. Tridentatae remains problematic. Presence of “ray” florets (though rare) and vestigial spines on the pollen (R. P. Wodehouse 1935) suggest a relationship with groups ancestral to Tridentatae. The species also has the unusual characteristic of lignified trichomes (L. M. Shultz 1986b). Further research may help to determine proper placement; its affinities may be with members of subg. Artemisia. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 19, p. 512. | FNA vol. 19, p. 509. |
Parent taxa | Asteraceae > tribe Anthemideae > Artemisia > subg. Tridentatae | Asteraceae > tribe Anthemideae > Artemisia > subg. Drancunculus |
Sibling taxa | ||
Synonyms | A. petrophila, Seriphidium bigelovii | |
Name authority | A. Gray: in War Department [U.S.], Pacif. Railr. Rep. 4(5): 110. (1857) | Nuttall: Trans. Amer. Philos. Soc., n. s. 7: 399. (1841) |
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