Ambrosia confertiflora

de Candolle in A. P. de Candolle and A. L. P. P. de Candolle

in A. P. de Candolle and A. L. P. P. de Candolle, Prodr. 5: 526. 1836

Synonyms: Franseria confertiflora (de Candolle) Rydberg
Treatment appears in FNA Volume 21. Treatment on page 18. Mentioned on page 11.
Perennials, 20–80(–150+) cm. Stems erect. Leaves mostly alternate; petioles 10–35 mm; blades lanceolate to ovate, 40–85(–150) × 20–35(–55) mm overall, laciniately 2–4-pinnately lobed (lobes ± lanceolate); bases cuneate to truncate, ultimate margins entire, abaxial and adaxial faces strigillose to sericeous (often grayish) and gland-dotted. Pistillate heads clustered, proximal to staminates; florets 1(–2). Staminate heads: peduncles 0.5–2 mm; involucres cup-shaped, 1.5–3+ mm diam., strigillose; florets 5–20+. Burs: bodies pyramidal to pyriform, 1–2 mm, strigillose to pilosulous, spines (1–)5–12+, mostly distal, stoutly conic to subulate, 0.5–1 mm, tips uncinate. 2n = 72, 108.

Phenology: Flowering (May–)Sep–Dec.
Habitat: Waste places, disturbed sites
Elevation: 10–2000 m

Distribution

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Ariz., Calif., Colo., Kans., N.Mex., Okla., Tenn., Tex., Utah, Mexico.

Discussion

References

None.

Lower Taxa

No lower taxa listed.