Poorjoe

Hexasepalum teres, commonly known as poorjoe, rough buttonweed or grassbur, and formerly placed in the genus Diodia as Diodia teres, is a small annual herb in the family Rubiaceae native to a wide range across the eastern and central United States, Mexico, Central America and the Caribbean to northern South America, where it occurs in dry sandy fields, open woods, roadsides, lawns and disturbed pinelands. The plant grows 10 to 50 centimetres long, with much-branched, prostrate to ascending stems that are square in cross-section and clothed in stiff retrorsely-pointing hairs, frequently rooting at the lower nodes. The opposite leaves are sessile, linear-lanceolate to narrowly oblong, 1 to 3 centimetres long and 2 to 5 millimetres wide, with rough scabrous margins and a prominent midrib; conspicuous fringed stipules joined to the leaf bases form a sheath around the stem with several stiff bristles. The small four-lobed funnel-shaped flowers are sessile in the leaf axils, pale lavender to pinkish or white, 4 to 6 millimetres long. The fruit is a hairy obovoid schizocarp 3 to 4 millimetres long crowned by four persistent calyx lobes that splits into two single-seeded mericarps at maturity.