Rautahi, Cutty Grass
Carex polystachya A.Rich.
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.
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
Endemic. New Zealand: North and South Islands. Widespread in the North Island. In the South Island more common in the northern half, sporadic further south.
Coastal to lowland (rarely montane). Usually on the margins of peat swamps, or in very wet alluvial forest.
Rhizomatous; robust, 0.5-1.5 m tall, bright green to dark green. Culms 1.5-5.0 mm diameter, triquetrous, scabrid on the edges; basal sheaths dull brown or red-brown, margins shredding into fibres wrapped round the culm. Leaves numerous usually much > culms, 3.5-8.0 mm wide, double-folded, margins scabrid. Spikes 6-20, pendulous on filiform peduncles, or upper spikes erect, sessile; upper 3-6 spikes male, sometimes mixed with female flowers, solitary or the lower geminate, 2-4 mm diameter, glumes hardly awned; remaining spikes female, usually with male flowers at the top, geminate, ternate or occasionally quinate, lowermost spikes 20-90 × 4-7 mm, upper spikes progressively smaller. Glumes (excluding awn) < utricles, narrow-ovate, obtuse, truncate or emarginate with a hispid awn of variable length, red-brown with a light brown, 3-nerved midrib, margins narrow, hyaline. Utricles 2.6-3.8 × 1.3-2.3 mm, ovoid to oblong, saccate, inflated or unequally compressed, 6-10-nerved on each face, olive green, becoming greenish brown or red-brown, soft, margins glabrous; beak very narrow, c.0.2 mm long, orifice entire, rarely slightly bidentate. Stigmas 2. Nut c.1.5 mm long, in lower half of utricle, biconvex, orbicular-ovoid or obovoid, brown
Carex lessoniana is allied to C. coriacea Hamlin, C. ternaria Boott, and C. germinata Schkuhr. From all these species it can be distinguished by the compact inflorescences, with wider, though smaller, initially erect spikelets (the basal few are always pendulous), and by distinctly beaked utricles. However, in some specimens the beak can be minute. Carex ternaria is unlikely to be confused because it confined to the Chatham and Subantarctic islands outside the range of C. lessoniana, while ecologically C. lessoniana and C. geminata often overlap, C. lessoniana is more common in wetter and/or more acidic habitats – such as peat bogs. Only rarely do the ranges of C. lessoniana and C. coriacea overlap, and then only in the south-eastern limits of its range.
October - December
December - April
Nuts surrounded by inflated utricles are dispersed by granivory and wind (Thorsen et al., 2009).
Easily grown from fresh seed and by the division of established plants. Although a wetland species C. lessoniana will grow well in most soils and moisture regimes. Does best in partial shade.
carex: Latin name for a species of sedge, now applied to the whole group.
lessoniana: Named after René Primevère Lesson who was a 19th century French botanist and surgeon
Fact Sheet prepared by P.J. de Lange (10 August 2006). 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 2009 Vol. 11 No. 4 pp. 285-309
Please cite as: de Lange, P.J. (Year at time of access): Carex lessoniana Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/carex-lessoniana/ (Date website was queried)