Microthlaspi perfoliatum
Feddes Repert. 84: 453. 1973.
Stems unbranched or branched basally or distally, (0.3–)0.5–2.8(–4) dm. Basal leaves (not rosulate or loosely so); petiole 0.5–1.3 cm; blade ovate or broadly elliptic, 0.3–2(–2.7) cm × 2–10 mm, base cuneate or attenuate, margins entire or, rarely, obtusely and sparsely dentate, apex rounded. Cauline leaves: blade ovate-cordate or suboblong, (1–)2–4(–5.5) cm × (2–)5–15(–20) mm, base cordate-amplexicaul, margins entire or repand, apex obtuse. Fruiting pedicels (2.5–)4–6(–8) mm. Flowers: sepals (0.8–)1–1.5(–2) × 0.5–1 mm, (margins white); petals 1.5–3.5(–4.7) × 0.5–1.3 mm; filaments 1–1.5(–2) mm; anthers 0.1–0.2 mm. Fruits 3–6.5(–8) × (2.5–)3–6(–7) mm, base obtuse, apical notch 1–1.5 mm deep; wings 1–2 mm wide apically, much narrower basally; style obsolete or 0.1–0.3 mm. Seeds yellow-brown, 0.9–1.3(–1.5) × 0.7–1(–1.2) mm. 2n = 14, 28, 42.
Phenology: Flowering Mar–May.
Habitat: Waste grounds, roadsides, fields, plains, thickets
Elevation: 0-500 m
Distribution
Introduced; Ill., Ind., Kans., Ky., Md., Mo., N.J., N.Y., N.C., Ohio, Pa., Tenn., Va., Wash., W.Va., Europe, Asia, n Africa.
Discussion
Selected References
None.