Thlaspi arvense L.
field penny-cress
Annual glabrous herb. Stems erect, simple or branched above, foetid when crushed, 20-60 cm tall. Lvs entire to dentate. Lower lvs ovate to elliptic to spathulate, narrowed to base, withering at flowering, c. 2-4 × 1-2 cm. Upper lvs amplexicaul, ovate to oblanceolate, c. 2-4 × 0.5-1 cm. Racemes 10-30 cm long; pedicels erecto-patent at flowering, spreading at fruiting. Sepals spreading, 1.5-2 × c. 1 mm. Petals white, 2.5-4 × 0.8-1 mm. Silicle obovate to ± circular, deeply notched at apex, 1-1.5 × 0.8-1.5 cm; valves reticulately veined; wing to 5 mm wide; stigma ± sessile in notch of silicle. Seeds ovoid, furrowed, dark brown, not winged, c. 2 mm long.
N.: Wairarapa, Wellington; S.: Canterbury, Otago, Southland.
Europe 1910
Arable fields, waste land.
