Plants of South Eastern New South Wales
Nasturtium microphyllum
Common name
One-rowed watercress
Family
Brassicaceae
Where found
In mud or shallow water. Coast and tablelands, occasionally in the ranges. Uncommon.
Notes
Introduced perennial herb to 0.6 m high or sprawling. Stems hairless, hollow. Leaves alternating up the stems, mostly to 10 cm long, compound, with 3-19 leaflets, leaflets almost round, hairless, margins scalloped to entire. Leaves becoming smaller up the stems. Flowers with 4 white petals each 4–5 mm long. Flowers in short clusters at the tops of the stems. Flowers mostly summer. 'Pods' curved, 1.5–3 cm long, 1–2 mm wide, pointing up or spreading, stalks spreading to pointing down, 9-15 mm long. Seeds in 1, or sometimes 2 somewhat irregular rows, on either side of a central division.
Reliable differentiation of this species from Nasturtium officinale requires examination of the arrangement of the seeds in the 'pods', and often microscopic examination of a seed.
PlantNET description: https://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Nasturtium~microphyllum (accessed 20 April 2021)
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