Carex buchananii
Common names
Buchanan’s sedge, cutty grass
Biostatus
Native – Endemic taxon
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.
- 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 | At Risk – Declining | Qualifiers: DPS, DPT
Category
Vascular
Structural class
Sedges
Detailed description
Densely tufted, strict, reddish brown, rarely yellow-green, sedge arising from an ascending rhizome c. 3 mm diameter. Culms 70–900 × 0.5–1.5 mm. erect, rarely elongating to 1.2 m and becoming prostrate, semiterete, smooth and shining, basal sheaths dark red-purple, almost black. Leaves = or slightly > culms, c.1.0–1.5 mm wide, plano-convex, often semiterete, erect, wiry, linear, gradually narrowed and flattened towards the acute, occasionally cirrhose apices, smooth and shining, reddish or green on the back, upper surface matt, pale cream, margins scaberulous towards the base, more strongly serrulate towards the tip, sheath not much broader than lamina and of similar texture, with finely membranous margins. Spikes 5–6, silvery, distant, or the upper spikes approximate, sessile or the lowest slightly pedunculate; uppermost 1–(2) spikes male, cylindrical; lower spikes female, 5–30 × 3–4 mm., oblong, occasionally with a few male flowers at the base; bracts subtending lower spikes lf-like, much > inflorescence. Glumes (excluding awn) < or = utricles, ovate, acute, white and membranous, with a stronger midrib and long scabrid awn. Utricles 2.5–3.0 mm long, slightly > 1 mm wide, plano-convex, elliptic-ovoid, pale cream at the base with dark brown to purple-black splotches above or occasionally entirely pale green, faintly nerved, margins scabrid above, abruptly narrowed to a pale slender, recurved, deeply bifid beak, 0.5–1.0 mm long, margins ciliate-serrate, orifice scabrid, stipe minute. Stigmas 2. Nut c. 1.5 mm, long, plano-convex to almost biconvex, obovoid, tapering towards the base, brown.
Similar taxa
A very distinct and singular species easily recognised by the mostly reddish brown culms and leaves, rather tall, stiffly erect tufted habit, plano-convex often semiterete leaves, membranous, colourless glumes and usually dark-coloured utricles. The scabrid-beaked utricles resemble those of Carex albula Allan and C. comans Bergg., much smaller species from which C. buchananii differs by its taller, stiffly erect culms and leaves, and two rather than three stigmas.
Distribution
Endemic. New Zealand: North Island (uncommon, known only from scattered sites south of the Manawatu. Naturalised in Auckland City.), South Island (more widespread and at times locally common, though often sporadically distributed, and apparently absent from Westland and Fiordland. Scarce in Southland).
Recorded as naturalised in the United Kingdom.
Habitat
Coastal to montane (up to 1000 m a.s.l.). On beaches, lagoon, lake and stream margins, or in damp ground within open forest or short tussock grassland.
Detailed taxonomy
Genus
Family
Synonyms
Carex tenax Bergg., Carex lucida Boott var. buchanani (Bergg.) Kük.
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
October–December
Fruiting
November–June
Life cycle and dispersal
Nuts surrounded by inflated utricles are dispersed by granivory and wind (Thorsen et al., 2009).
Propagation technique
Easily grown from fresh seed and by the division of whole plants. Will tolerate most conditions, but does best in full sun in a permanently damp soil. In ideal conditions this species often naturalises, and it can at times become invasive. Next to C. comans, this is one of the most commonly cultivated indigenous sedges.
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]
FAC: Facultative
Commonly occurs as either a hydrophyte or non-hydrophyte (non-wetlands).
Other information
Etymology
carex: Latin name for a species of sedge, now applied to the whole group.
buchananii: Named after John Buchanan (13 October 1819-1898) who was a New Zealand botanist and scientific artist and fellow of the Linnean Society.
Manaaki Whenua Online Interactive Key
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.
CARBUC
Chromosome number
2n = 60
Previous conservation statuses
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.
- 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.
2017 | At Risk – Declining | Qualifiers: DP
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Regional conservation statuses
Otago: 2025 | Regionally Threatened – Regionally Vulnerable | Qualifiers: DPS, DPT, NStr, Sp
The regional threat classification system leverages off the national assessments in the NZTCS, providing information relevant for the regional context. Otago conservation status information is sourced from the “Conservation Status of Indigenous Vascular Plants in Otago, 2025” Jarvie S et al. (2025) report.
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. https://doi.org/10.1016/j.ppees.2009.06.001.
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.