Ambrosia cordifolia

(A. Gray) W. W. Payne

J. Arnold Arbor. 45: 421. 1964.

Basionym: Franseria cordifolia A. Gray in A. Gray et al., Syn. Fl. N. Amer. 1(2): 445. 1884
Treatment appears in FNA Volume 21. Treatment on page 14. Mentioned on page 11.

Shrubs, 30–50+ cm. Stems erect. Leaves mostly alternate; petioles 3–35 mm; blades deltate to rounded-deltate, 10–35(–80) × 10–30(–70) mm, bases cordate to truncate, margins coarsely toothed, abaxial faces densely puberulent (including veins), adaxial faces strigillose to scabrellous and gland-dotted. Pistillate heads clustered, proximal to staminates; florets (1–)2. Staminate heads: peduncles 0–1 mm; involucres cup-shaped, 2–3(–5) mm diam., strigillose; florets 8–30+. Burs: bodies ± globose to fusiform, 3–4+ mm, tomentulose and stipitate-glandular, spines 8–20+, scattered, ± subulate (basally navicular), 1–2 mm, tips straight or uncinate.

Phenology: Flowering Mar–Apr.
Habitat: Sandy washes, benches
Elevation: 700–1200 m



Ariz., Mexico (Sinaloa, Sonora).


Selected References


Lower Taxa