Origin:
Native to eastern North America, and introduced to the western states where it now can be found throughout most of the continent.
Biology:
An annual weed that reproduces from seeds. Plants favor moist soils, but will tolerate growth on most habitats, including roadsides, landscapes, and in many crop settings. Generally it is not a problem in turf.
Identification:
Plants have fairly weak stems that may grow either erect or sprawling, with growth to nearly 2 feet in height. Stems have multiple branching and are green to reddish, swollen at the joints and with the characteristic papery sheath (ocrea) around the joint and the bases of the leaves there. Leaves are shiny green and smooth, alternate, and lanceolate to somewhat egg-shaped and pointed. The leaf usually has a darker blotch of color in the central area on both surfaces. Flowers are grouped in elongated, dense clusters at the ends of the stems. They are bright pink to whitish.
Characteristicts Important to Control:
Plants may be physically removed, or a contact or systemic herbicide will be effective in killing the plants. Control of moisture will help to discourage the presence of this weed.
