Sharp spike sedge
Eleocharis acuta R.Br. var. platylepis Hook.f.; Eleocharis acuta R.Br. var. tenuis Carse
Vascular – Native
The National Vegetation Survey (NVS) Databank is a physical archive and electronic databank containing records of over 94,000 vegetation survey plots - including data from over 19,000 permanent plots. NVS maintains a standard set of species code abbreviations that correspond to standard scientific plant names from the Ngä Tipu o Aotearoa - New Zealand Plants database.
2n = 20
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2017 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2012 and replaces all previous NZTCS lists for vascular plants. Authors: By Peter J. de Lange, Jeremy R. Rolfe, John W. Barkla, Shannel P. Courtney, Paul D. Champion, Leon R. Perrie, Sarah M. Beadel, Kerry A. Ford, Ilse Breitwieser, Ines Schönberger, Rowan Hindmarsh-Walls, Peter B. Heenan and Kate Ladley.
2012 | Not Threatened
Previous conservation statuses
2009 | Not Threatened
2004 | Not Threatened
Indigenous. In New Zealand found on the Kermadec, North, South, Stewart and Chatham Islands. Also in Australia and on Norfolk Island.
Coastal to montane. Common in open to partially shaded permanently damp ground. Usually in swamps, and on stream, river, pond, and lake margins. Sometimes present in seepages within pasture.
Terrestrial or semi-aquatic sedge forming yellow-green to green somewhat distinct, crowded tufts. Rhizomes, lignaceous, widely creeping, 1-2 mm diameter. Culms more or less crowded in distant tufts, 15.0-900.0 x 0.5-2.5 mm, more or less erect, terete, distinctly striated; lower sheath dark red to maroon with an oblique orifice, upper sheath paler, closely appressed to culm, orifice usually truncate or rarely slightly oblique, with dark thickened edge and distinct mucro at back. Spikelet 5-25 x 2-5 mm, cylindrical, acute at apex. Glumes numerous, basal 2 sterile, shorter, broader and paler than rest, upper glumes ovate-lanceolate with hyaline apices. Hypogynous bristles 6-8, some =, some > nut. stamens 3. Style 3-fid. Nut 1.5 x 1.0 mm, obovoid, biconvex or plano-convex, pale brown, smooth or faintly reticulate; the small persistent style-base triangular, compressed, white or very pale brown.
Distinguished from the somewhat similar E. pusilla R.Br. and E. gracilis R.Br. by the much larger size, and by the usually truncate (only rarely slightly oblique), distinctly mucronate uppermost leaf-sheath which has a thickened orifice. In the other two species the uppermost leaf-sheath has a consistently oblique orifice and is without a mucro.
September - January
October - May
Bristly nuts are dispersed by water and possibly wind and attachment (Thorsen et al., 2009).
Easy from fresh seed and the division of whole plants. Does best partially submerged but will also grow in damp soil. Needs full sun to flower
eleocharis: Charm of the swamp
acuta: Sharp (sheath mucronate)
Where To Buy
Occasionally sold by specialist native plant nurseries.
Description adapted from Moore and Edgar (1970)
References and further reading
Moore, L.B.; Edgar, E. 1970: Flora of New Zealand. Vol. II. Government Printer, Wellington.
Thorsen, M. J.; Dickinson, K. J. M.; Seddon, P. J. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285-309