Nasturtium officinale W.T.Aiton

Perennial stoloniferous herb. Stems trailing, glabrous, to several m long. Lvs glabrous, all similar, but becoming smaller near infl., pinnate, petiolate, 2–10–(25) × 1–5 cm; basal auricles small; leaflets rounded, ovate; margins entire or sinuate. Pedicels glabrous, slender, erecto-patent, spreading to deflexed at fruiting, (5)–10–15–(18) mm long (very rarely to 30 mm). Sepals 1.5–2.5 × 0.7–1.5 mm. Petals white, (3)–4–6 × (1)–1.5–2.5 mm. Silique glabrous, narrow-oblong, curved, (8)–12–15–(18) × 2–2.5 mm; valves with distinct midrib, at least below; style c. 1 mm long. Seeds distinctly in 2 rows per locule, brown, c. 1 mm long, coarsely reticulate with 20–50 polygonal depressions per face.

[From: Webb et al. (1985) Flora of New Zealand. Volume 4 as Rorippa nasturtium-aquaticum (L.) Hayek]