Flora of New Zealand Series

wall cress

Annual herb; rosette small. Stems erect, 5-20-(40) cm tall, bearing patent simple hairs below. Lvs all hairy, with simple, 2-fid and branched hairs. Rosette lvs petiolate; lamina ovate to obovate, entire or very shallowly and bluntly toothed, (3)-5-25 × (2)-3-10 mm. Stem lvs few, smaller, simple, sessile, obovate to narrow-ovate, cuneate at base. Racemes 10-20-(40) cm long. Pedicels slender, erecto-patent, spreading at fruiting, 5-7 mm long. Sepals oblong, 1-1.5 mm long, glabrous or with a few hairs at apex. Petals white, narrow-obovate, 2.5-3.5 mm long. Stamens 6, rarely 4, slightly < petals. Silique held at slight angle to pedicel, curving upward, glabrous, (8)-10-15 × c. 0.5 mm; style c. 0.2 mm long. Seeds brown, 0.3-0.5 mm long, in 1 row per locule.

N.: Auckland, Taranaki; S.: Nelson, Canterbury, Otago.

Temperate Eurasia, N.Africa 1885

Locally common in waste places, gardens, railway ballast.

This sp. has also been referred to in N.Z. as Sisymbrium thaliana.