Schoenoplectus pungens
Common names
three-square
Biostatus
Native
Category
Vascular
Structural class
Sedges
Detailed description
Summer-green perennial. Rhizome 2–8 mm diameter, woody, with membranous, chartaceous scales at the nodes and numerous reddish fibrous roots. Culms 0.15–1.8 m, 1–6 mm diameter, pale glaucous-grey to dark green, triquetrous, with concaves sides, smooth, soft, bearing 1–2 very thin, membranous sheaths at the base. Leaves 1–4, < culm, 1–3 mm wide, linear, channelled, becoming triangular with margins sparingly scabrid towards the obtuse apex, adaxial surface membranous with obvious internal septa; sheaths long, closed, largely membranous. Inflorescence apparently lateral, of 1–4 unequal, closely compacted, sessile, spikelets; subtending bract 20–60 mm long, similar to stem and continuous with it, scabrid towards apex. Spikelets 6–11 × 3–5 mm, ovate, elliptic, dark purple-brown. Glumes broadly ovate, smooth, membranous, margins fimbriate, emarginate, midrib prolonged, mucronate, small, round teeth of glume apex. Hypogynous bristles 2–6, < nut, retrorsely scabrid, red-brown. Stamens 3. Style-branches 3. Nut 3 × 2 mm, obovoid, plano-convex to subtrigonous, prominently apiculate, smooth, grey-brown.
Similar taxa
Schoenoplectus pungens is not easily confused with either S. californicus (C.A.Mey.) Palla or S. tabernaemontani (C.C.Gmel.) Palla, species that are much taller (up to 4 m cf. 1 m in S. pungens), and have umbellate inflorescences bearing many spikelets, rather than dense, compact, sessile inflorescences of 1–3 spikelets. Furthermore, neither S. californicus or S. tabernaemontani have culms that are uniformly 3-angled for their entire length.
Distribution
Indigenous. North, South and Chatham Islands. In the North Island found from West Auckland and Coromandel south, often scattered and apparently absent from Taranaki, extending inland along the Waikato River. In the South Island scattered and uncommon in Westland and Fiordland—found inland at Pareora Gorge (Canterbury) and Central Otago. Common on Chatham Island. Widespread in western Europe, America and Australia.
Habitat
Coastal to montane (up to 400 m a.s.l.). Usually not far from the sea in saltmarshes, brackish swamps and estuaries. Also more rarely found inland around freshwater lakes and ponds, and in damp saline slacks. Also recorded from waters draining geothermal sites along the Waikato River.
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 | Qualifiers: SO
Detailed taxonomy
Family
Cyperaceae
Synonyms
Scirpus pungens Vahl; Scirpus novae-zelandiae Colenso; Scirpus americanus Pers. mispl. name; Schoenoplectus americanus (Pers.) Volkart ex Schinz et R.Keller, mispl. name; Fimbristylis rara R.Br.; Iria rara (R.Br.) Kuntze
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Flowering
October–January
Fruiting
January–June
Propagation technique
Easily grown from fresh seed and the division of whole plants.
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]
OBL: Obligate Wetland
Almost always is a hydrophyte, rarely in uplands (non-wetlands).
Other information
Where To Buy
Not commercially available
Etymology
pungens: Sharp-pointed
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.
SCHPUN
Previous conservation statuses
2017 | Not Threatened | Qualifiers: SO
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.
Attribution
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.