Scirpus fluviatilis
Rhizome with globose woody tubers. Stems to 2 m high. Leaves broad. Inflorescence a compound irregular umbel with leaf-like bracts. Hypogynous bristles ± = nut. Stamens 3. Style-branches 3. Nut trigonous, equilateral, dorsal angle acute.
N. North Auckland; Auckland; Gisborne; Hawkes Bay; Wellington. S. Canterbury - Akaroa. Usually coastal in freshwater or brackish swamps and on river margins. (Australia)