Native. Annual. Propagates by seeds. Time of bloom: July to October. Seed-time: August to November. Range: Rhode Island to Ontario, Illinois, and Kansas, southward to Georgia and Louisiana. Most common in the South. Habitat: Dry fields, meadows, pastures, roadsides, and waste land.
An unpleasant, viscidly hairy, and homely weed, much too common in some localities. Cattle will not eat it and its deep-boring roots absorb a large amount of the food and moisture needed by better plants.
Stem six to eighteen inches in height, round, red, branching, thickly set with sticky hairs to which small dead or dying insects are often seen adhering. Leaves opposite, long ovate, rough, entire, viscid, especially on midribs and veins, and tapering abruptly to short sticky-hairy petioles. Flowers on very short peduncles, not rising directly from the axils but from the side of the stem between the opposite leaf-stalks; they are less than a half-inch broad, bluish purple, with six very unequal petals, a tubular six-toothed, twelve-ribbed calyx, swollen at base on the upper side, and often ruddy-colored like the stem; stamens eleven or sometimes twelve; style slender with two-lobed stigma; ovary unequally two-celled, with a curved gland at its base. The capsule bursts lengthwise and the seeds protrude from its side while still immature and attached to one side of the placenta; they ripen while exposed to the open air and then drop off into the soil, where they are said to retain their vitality for several years.
Prevent seed development by closely cutting or uprooting the plants while in their first bloom.