Author

Slade Quentin Colligan

Ecology

Commonly found in disturbed sites, roadside ditches, waste places, damp soils; 0–1600 m Alt.

Family

Asteraceae/Compositae (aster or sunflower family)

Flowering period

Flowering Jul–Nov

Fruit

Cypselae (black) ± ovoid or fusiform, enclosed within pyramidal bur;
Burs 3–7+ mm, glabrous or glabrate, spines 4–5, ± distal, ± acerose, 0.5–1 mm, tips straight, bases ± decurrent as ribs.

Top

Leaves mostly opposite; petioles 10–70+ mm; blades rounded-deltate to ovate or elliptic, 40–250 × 30–70(–200+) mm, usually some blades palmately 3–5-lobed, bases truncate to cuneate sometimes decurrent onto petioles, margins usually toothed, rarely entire, abaxial and adaxial faces ± scabrellous and gland-dotted.

Leaves

Monoecious annuals, 30–150(–400+) cm. Stems erect.

Plant and Stem Features

Strother, John L. 2006.  Ambrosia Linnaeus. In: Flora of North America North ofMexico . Flora of North America Editorial Committee. Vol. 21. Oxford University Press, New York and Oxford .

USDA, NRCS. 2006. The PLANTS Database (http://plants.usda.gov, 4 December 2006).National Plant Data Center, Baton Rouge, LA 70874-4490 USA.

References

FAC

Asteraceae, Ambrosia, trifida

Top