Flora of New Zealand Series

hoary mustard

Annual to perennial. Hairs stiff, simple, recurved. Stem ± stout, often much-branched, densely hairy below, becoming glabrous above, 30-70-(100) cm tall. Lvs all densely hairy, petiolate. Rosette lvs crowded, 4-10-(30) × 1.5-3-(6) cm; terminal leaflet ovate to oblong, rarely ± triangular, often with 1-2 rounded lobes at base; lateral lobes oblong to triangular, ± auriculate at base; margins irregularly bluntly serrate to crenate. Stem lvs few, smaller than rosette lvs and with fewer leaflets, bluntly serrate, the uppermost simple, narrow-oblanceolate. Racemes many, obliquely spreading, 30-50 cm tall. Pedicels erect, swollen and narrowly clavate at fruiting, 4-8 mm long. Sepals 2-3 × 0.5-1 mm, oblanceolate. Petals pale yellow, often with dark veins; claw narrow, c. (⅓) as long as limb. Silique glabrous, erect, 6-10 × 1-2 mm; valves 4-6 mm long, 3-veined when immature but veins obscure when mature; beak swollen, 2-4 mm long, (0)-1-(2)-seeded. Seeds c. 1 mm long, (1)-3-5 per locule.

N.; S.: occasionally locally established throughout but particularly abundant in Hawke's Bay, from Wairoa to Waipukarau.

W., C., and S. Europe, S.W. Asia 1899

Waste land, especially near ports, on railway ballast and roadsides.

This sp. has also been referred to in N.Z. as Brassica adpressa, Erucastrum incanum, Sinapis adpressa and S. incana.