Carex colensoi
Common names
Colenso’s sedge
Biostatus
Native
Category
Vascular
Structural class
Sedges
Detailed description
Patchy, diffuse long trailing light green, grass-like, rather slender tufted sedge arising from a long-creeping rhizome. Rhizome 2–3 mm diameter, woody, often much branched and knotted, with shoots spaced singly and evenly along it, 1.0–1.5 mm diameter at base. Culms rather variable in height, 40–450 × c. 0.5 mm, trigonous, flaccid, glabrous; basal sheaths cream, grey, or light brown. Leaves usually < culms, occasionally = or > culms, 0.5–1.5 mm wide, soft, grass-like, channelled, occasionally almost flat, margins minutely serrulate just below trigonous tip. Inflorescence 10–15 mm long, of 1–4 clustered, shortly-peduncled, chestnut-brown spikes, subtended by a green, filiform, leaf-like bract, much > inflorescence, with margins minutely serrulate. Spikes androgynous, 7–10 × 2–5 mm, ovoid, male flowers at the base. Glumes = or slightly > utricles, ovate, subacute, brown, with a broad green midrib and broad silver hyaline margins. Utricles 2.5–3.5 × 1.5–2.0 mm, plano-convex, occasionally almost subtrigonous when mature, brown, shining, with nerves not distinct, margin of upper part finely scabrid; beak hardly developed, c.0.5 mm long; stipe c.0.5 mm long. Stigmas 2. Nut c. 1.5 mm long, ± biconvex, elliptic-oblong to orbicular, brown with a distinct stipe c. 0.2 mm long.
Similar taxa
Perhaps most similar to Carex inversa R.Br., from which it is distinguished by the long trailing habit, very slender, light-green rather than shortly creeping, dark to yellow-green culms topped by relatively large inflorescences composed of 1–4, clustered brown rather then 2–5 pale green to light yellow-brown spikes, bearing scarcely beaked utricles with indistinct nervation rather than prominently beaked and nerved.
Distribution
Endemic. North (from northern Kaimanawa Ranges south, uncommon) and South Islands.
Habitat
Mostly montane to subalpine in short- tussock and tall-tussock grassland. Especially common in the drier intermontane basins of the eastern South Island.
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – these interim threat classification statuses has not been assessed by the NZTCS panel.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2023 | Not Threatened
Detailed taxonomy
Family
Cyperaceae
Synonyms
Carex picta Colenso
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
October–December
Fruiting
November–May
Life cycle and dispersal
Nuts surrounded by inflated utricles are dispersed by granivory and wind (Thorsen et al., 2009).
Propagation technique
Easily grown from the division of whole plants and from fresh seed. Best suited to a well-drained, sunny site in dry climates. Dislikes humidity and soon dies if kept too moist. An unusual sedge well worth cultivating.
Wetland plant indicator status rating
Information derived from the revised national wetland plant list prepared to assist councils in delineating and monitoring wetlands (Clarkson et al., 2021 Manaaki Whenua – Landcare Research Contract Report LC3975 for Hawke’s Bay Regional Council). The national plant list categorises plants by the extent to which they are found in wetlands and not ‘drylands’. The indicator status ratings are OBL (obligate wetland), FACW (facultative wetland), FAC (facultative), FACU (facultative upland), and UPL (obligate upland). If you have suggestions for the Wetland Indicator Status Rating, please contact: [Enable JavaScript to view protected content]
FACU: Facultative Upland
Occasionally is a hydrophyte but usually occurs in uplands (non-wetlands).
Other information
Etymology
carex: Latin name for a species of sedge, now applied to the whole group.
colensoi: Named after William Colenso (7 November 1811 - 10 February 1899) who was a Cornish Christian missionary to New Zealand, and also a printer, botanist, explorer and politician.
NVS code
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.
CARCOL
Chromosome number
2n = c.60-64
Previous conservation statuses
2017 | Not Threatened
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Referencing and citations
References and further reading
Moore LB, Edgar E. 1970. Flora of New Zealand, Volume II. Indigenous Tracheophyta: Monocotyledones except Gramineae. Government Printer, Wellington, NZ. 354 p.
Thorsen MJ, Dickinson KJM, Seddon PJ. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285–309.
Attribution
Fact Sheet prepared by P.J. de Lange (10 August 2006). Description adapted from Moore and Edgar (1970)
Some of this factsheet information is derived from Flora of New Zealand Online and is used under a Creative Commons Attribution 3.0 New Zealand licence.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Carex colensoi Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/carex-colensoi/ (Date website was queried)