Origin:
Native to the Old World tropics, but now found throughout the tropical regions of the world. In the United States it can be found commonly in Florida, Hawaii, Texas and Louisiana. It also is found through Mexico into South America and in the West Indies.
Biology:
A warm season annual with a deep taproot. Plants have multiple branches and may grow to about 1.5 feet in height. It may be found in almost any disturbed site, such as roadsides, waste lots, turf, or landscape. Reproduction is from seeds.
Identification:
Stems are usually fleshy but weak, causing the plant to fall over and sprawl as it grows. The stems are smooth near the top and hairy near the base. The majority of the leaves occur near the base of the plant. They are alternate and spear-shaped, with toothed margins, and the basal leaves are clasping at the stem and have broad tips. The flowers occur at the ends of long stalks in groups of 3 or 4 flower heads. They are bright pink to reddish and are urn-shaped, not often fully opening, but remaining bunched in the long calyx.
Characteristicts Important to Control:
Physical removal of single plants is effective. When found in turf most members of the sunflower family can be effectively controlled with a selective broadleaf herbicide. Prevention of seed germination can be accomplished with a pre-emergent herbicide.
