Ambrosia dumosa

(A. Gray) W. W. Payne
J. Arnold Arbor. 45: 422. 1964.
Common names: Bursage
Basionym: Franseria dumosa A. Gray in J. C. Frémont, Rep. Exped. Rocky Mts., 316. 1845
Treatment appears in FNA Volume 21. Treatment on page 13. Mentioned on page 10, 12.

Shrubs, 10–40(–60+) cm. Stems erect. Leaves mostly alternate; petioles 2–8(–12+) mm; blades (white) ovate to elliptic, 10–25(–45) × 8–15(–30) mm, (1–)2–3-pinnately lobed, abaxial and adaxial faces densely strigillose. Pistillate heads intermixed with staminates (sometimes wanting or staminates sometimes wanting, plants unisexual); florets (1–)2. Staminate heads: peduncles 0–1(–2) mm; involucres shallowly cup-shaped, 3–5 mm diam., ± strigillose; florets 8–15+. Burs: bodies ± globose, 3–5+ mm, pilosulous and/or gland-dotted, spines 12–25+, scattered, ± subulate (± navicular at bases), 2–4 mm, tips straight. 2n = 36, 72, 108, 126.


Phenology: Flowering Mar–May(–Dec).
Habitat: Rocky or sandy washes, benches
Elevation: (-100–)100–1200(–1500) m

Distribution

V21-8-distribution-map.gif

Ariz., Calif., Nev., Utah, Mexico (Baja California, Sonora).

Discussion

Selected References

None.

Lower Taxa

None.

... more about "Ambrosia dumosa"
John L. Strother +
(A. Gray) W. W. Payne +
Franseria dumosa +
Bursage +
Ariz. +, Calif. +, Nev. +, Utah +, Mexico (Baja California +  and Sonora). +
(-100–)100–1200(–1500) m +
Rocky or sandy washes, benches +
Flowering Mar–May(–Dec). +
J. Arnold Arbor. +
Franseria +  and Hymenoclea +
Ambrosia dumosa +
Ambrosia +
species +