Native. Annual. Propagates by seeds.
Time of bloom: July to September.
Seed-time: August to October.
Range: Connecticut to Missouri, southward to Florida, Texas, and New Mexico.
This plant is very resistant to drought, having a slender taproot, often nearly a foot long, fringed with fine feeding rootlets. Stems several from the same root, four inches to two feet in length, ascending or sometimes prostrate, usually rough-hairy. Leaves opposite, lance-shaped to linear, rough-hairy on both sides, acute, rigid, sessile, the margins revolute in dry weather. Flowers usually solitary in the axils, the corolla funnel-form, five-lobed, about a quarter-inch long, pale purple; stamens four, with anthers exserted; style with two-parted stigma. Fruit small, obovoid or top-shaped, about one-sixth of an inch long, hard and rough-hairy, crowned with the four persistent calyx-teeth; it has two or occasionally three cells, and when ripe usually splits into two closed carpels. These seeds are a frequent impurity of southern grain and clover seed; and the weed is most undesirable company for those crops, as it absorbs much of the soil fertility. (Fig. 279.)
Fig. 279.- Rough Button-weed (Diodia teres). X 1/4.
Mow infested meadows before the development of seed; enrich the soil for the encouragement of the clover, aiding it to crowd out the intruder. As soon as the crop is removed from corn and potato ground, sow with winter annuals. Follow grain with a crop requiring frequent and late-continued hoe-culture.