Tithonia diversifolia
Proc. Amer. Acad. Arts 19: 5. 1883.
Perennials, subshrubs, or shrubs, to 250(–500) cm. Leaves: petioles 2–6 cm; blades ± deltate to pentagonal, 7–33 × 7–22 cm, sometimes 3- or 5-lobed, abaxial faces glabrous to hispid-pilose. Peduncles 7–24 cm. Phyllaries 16–28 in (3–)4 series, oblong to ovate; outer 6–10 × 4–7 mm, apices rounded to acute, abaxial faces usually glabrous; inner 10–20 × 3–10 mm, apices rounded to acute, abaxial faces glabrous. Paleae 10–13 × 2–3 mm, mucros 1.5–2.5 mm. Ray florets 7–14; corollas yellow, laminae linear, 48–69 × 9–16 mm. Disc florets 80–120+. Cypselae 4–6 mm. 2n = 34.
Phenology: Flowering Sep–Jan.
Habitat: Disturbed sites
Elevation: 0–20+ m
Distribution
Introduced; Fla., Tex., Mexico, also introduced in West Indies, Central America, Asia, Africa, Atlantic Islands, Indian Ocean Islands, Pacific Islands, Australia.
Discussion
Tithonia diversifolia is widely cultivated in warm climates and may persist after plantings; a report for Louisiana was not confirmed for this treatment.
Selected References
None.