The New Zealand Plant Conservation Network

Species

Carex lessoniana

Etymology

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

Common Name(s)

Rautahi, Cutty Grass

Current Conservation Status

2012 - Not Threatened

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Previous Conservation Status

2009 - Not Threatened
2004 - Not Threatened

Authority

Carex lessoniana Steud.

Family

Cyperaceae

Flora Category

Vascular - Native

NVS Species Code

CARLES

Structural Class

Sedges

Synonyms

Carex polystachya A.Rich.

Distribution

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.

Habitat

Coastal to lowland (rarely montane). Usually on the margins of peat swamps, or in very wet alluvial forest.

Features

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

Similar Taxa

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.

Flowering

October - December

Fruiting

December - April

Propagation Technique

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.

Threats

Not Threatened

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

Life Cycle and Dispersal

Nuts surrounded by inflated utricles are dispersed by granivory and wind (Thorsen et al., 2009).

This page last updated on 3 Jan 2017