1. Portulaca grandiflora Hook. (portulaca, moss rose, rose moss)

Pl. 506 c, d; Map 2313

Plants with the lateral roots fibrous. Stems 5–30 cm long, prostrate to strongly ascending, sometimes hairy toward the tip. Leaf blades 5–30 mm long, 1–4 mm wide, not flattened (circular to semicircular in cross-section), linear to narrowly triangular-lanceolate. Stipules represented by dense, conspicuous tufts of long, somewhat contorted hairs in the leaf axils. Inflorescences with dense, conspicuous tufts of long, somewhat contorted hairs. Sepals 7–11 mm long (measured to the base of the ovary). Petals 15–25 mm long, pink, red, purple, yellow, orange, bronze-colored, or white. Stamens numerous (except rarely in some horticulatural forms with doubled flowers). Fruits 5–8 mm long, 3–6 mm wide. Seeds 0.7–1.0 mm long, variously orbicular to kidney-shaped, the surface smooth or with minute tubercles or spines, gray to dark gray, often somewhat iridescent. 2n=18. July–September.

Introduced, known thus far only from Boone County and the city of St. Louis (native of South America; introduced widely but sporadically in the U.S. [except for the northwestern states], Canada, Europe). Banks of rivers; also railroads and roadsides.

This attractive species produces brightly colored flowers in a variety of different colors and is grown commonly in North America as a bedding plant.