Vascular – Exotic
Very tall (to 2.5 m) clump forming leafless reed-like plant with wide triangular stems several cm across, with many (often more than 100) drooping thread-like green flower branches at the top of each stem forming a mop-like structure.
Mostly northern North Island, usually close to habitation, but occasionally in remote sites.
Emergent in still and slow flowing water bodies.
Erect perennial sedge to 2.5 (4) m tall with triangular stems up to 4 cm across arising from short thick woody rhizomes. Leaves reduced to papery brown basal sheaths. Inflorescence terminal subtended by 4-10 deciduous sheath-like bracts 7-15 cm x 1 cm. Inflorescence compound often with >100 filamentous branches 10-25 cm x 1 mm, often sterile. Fertile spikes are 3-5 slikes with 20-30 spikelets, each 3-20 flowered. Viable seed production not known from New Zealand.
Distinctive tall leafless sedge with mop-like flower heads, unlikely to be mistaken for other naturalised sedges.
Perennial. Reproduces in New Zealand probably only by asexual spread through layering (seed is occasionally produced but it is not yet known if it is viable). Dispersed by deliberate planting or garden discards. However some occurrences are in very remote situations and are difficult to explain if they had originated from garden discards.
Reason for introduction
Not controlled in New Zealand.
cyperus: From the ancient Greek name for sedge, kypeiros
Factsheet prepared by Paul Champion and Deborah Hofstra (NIWA).
References and further reading
Sainty, G.R.; Jacobs, S.W.L. (1981). Waterplants of New South Wales. Water Resources Commission NSW. 550pp.