5. Cardamine flexuosa With.

Map 1335

Plants annual or biennial. Stems (6–)10–50 cm long, glabrous or sparsely to densely pubescent with spreading hairs near the base (and often also along the petioles). Basal leaves often withered at flowering time, (2–)4–10(–14) cm long, short-petiolate, pinnately compound with 5–13(–14) glabrous, stalked leaflets, the lateral leaflets circular to obovate or obovate to oblong, entire or with 1–5 irregular teeth, the terminal leaflet often broader than the lateral ones. Stem leaves usually 3–15, (1–)2–5 cm long, pinnately compound with 5–11 short-stalked leaflets, these linear to oblanceolate or ovate to circular, glabrous, the stalk broadened at the very base and extending slightly along the leaf rachis. Sepals 1.5–2.5 mm long, green. Petals 2.5–4.0(–5.0) mm long, white. Stamens (4)6. Styles 0.3–1.0(–1.5) mm long. Fruits (8–)12–28 mm long. Seeds 0.9–1.5 mm long, oval to oblong in outline, the surface with a fine, netlike or honeycomb-like pattern of ridges and pits, orange. 2n=32. March–July.

Introduced, uncommon and sporadic (native of Europe, introduced widely but sporadically in the eastern and midwestern U.S. and California). Greenhouses, gardens, and open, disturbed areas.

This species is spread primarily as a seed contaminant in the soil of bedding plants and other cultivated species distributed through the horticultural industry. It can be found as a weed in and around plant nurseries and also in flower beds, but it has not been documented to invade any natural habitats as yet. This is the first report of the species in Missouri.