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 = 60
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.
2018 | At Risk – Declining
Previous conservation statuses
2012 | At Risk – Naturally Uncommon | Qualifiers: Sp
2009 | At Risk – Naturally Uncommon
2004 | Sparse
Endemic. North and South Islands. In the North Island restricted to the Central Ranges where it is known from one site in the Moawhango. In the South Island mainly easterly from Lake Tennyson south. Apparently not known from Marlborough or Westland
A montane to subalpine (rarely lowland in the southern part of its range) wetland species inhabiting lake, tarn, pond, and stream side margins. It has also been collected from turfs bordering ephemeral wetlands.
Shortly rhizomatous, tufted dark purple red, wine-red, or orange red, tufted, small sedge. Culms 15-30 mm long, glabrous, terete, distinctly flattened above, almost completely enclosed by light brown leaf-sheaths. Leaves 30-60 x 1-2.5-3 mm, linear, concavo-convex, almost flat, nerves very distinct, margins not usually scabrid except towards the rather bluntly obtuse apex. Spikes 3-4(-6); terminal spike male, distinctly pedunculate; remaining spikes female, 5-8 mm long, ovate, sessile or shortly pedunculate, crowded at same level round base of male spike; leaf-like subtending bracts > inflorescence. Glumes rather < utricles, ovate, cuspidate, or entire and obtuse, membranous, red-brown with a paler brown midrib. Utricles 2-3 x 1.5 mm, biconvex or rarely subtrigonous, elliptic-oblong, turgid, red-brown to dark red-purple above, yellow below. Distinctly nerved at first, smooth at maturity, margins glabrous; beak minute with the scabrid crura very shortly bifid to almost truncate; stipe 0.2 mm long, stout. Stigmas 2-3. Nut 1.5 mm long, trigonous.
The remarkable broadly concavo-convex almost flat leaves with the distinctively bluntly obtuse leaf tips are unique to this species in New Zealand. Its nearest relatives would seem to be C. decurtata Cheeseman and C. hectorii Petrie. From C. decurtata, C. berggrenii differs by broadly concavo-convex flat leaves which taper little (if at all) toward the obtuse tip and from C. hectorii by its purple red, wine-red, or orange red, broad obtuse tipped leaves. From both C. decurtata and C. hectorii, C. berggrenii further differs by its utricle colour which is characteristically red-brown to dark red-purple above, yellow below, rather than light brown (C. decurtata) or dark brown (C. hectorii).
October - February
October - June
Nuts surrounded by inflated utricles are dispersed by granivory and wind (Thorsen et al., 2009).
Easily grown in small pots doing best in pots that are partially submerged in water. Can be grown in a rockery, provided it is kept damp and free from competition. An attractive sedge which deserves to be more widely cultivated than it currently is.
A biologically sparse species which is not so much threatened as nationally uncommon. However, some populations are now at risk through competition from taller and faster growing wetland weed species.
carex: Latin name for a species of sedge, now applied to the whole group.
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