Mexican sunflower

Tithonia diversifolia, known as the Mexican sunflower or tree marigold, is a robust short-lived perennial herb or soft-wooded shrub of the family Asteraceae growing 1.5-4 m tall, native to Mexico and Central America and now pantropically naturalized as a weed and forage plant. The thick green stems are erect, sparingly branched, often somewhat woody at the base and clothed in short hairs. The large alternate leaves are deeply 3-5 palmately lobed, ovate to broadly triangular in outline, 7-20 cm long, with coarsely serrate margins, an acute apex and a long winged petiole, the lobes resembling those of a maple. From late summer to winter the plant bears showy terminal solitary daisy-like flower heads 7-15 cm across on stout hollow peduncles. Each capitulum has a hemispheric involucre of green leafy bracts and 8-15 broad bright golden orange-yellow ray florets 3-6 cm long surrounding a central disc of numerous yellow tubular florets. The fruit is a flattened, 4-angled, hairy cypsela about 5 mm long bearing a pappus of two awns and several short scales. It grows vigorously in roadsides, disturbed ground, fallow fields and forest edges and is widely planted as an ornamental, green manure and bee plant.