Carex inversa
Common names
creeping lawn sedge
Biostatus
Native
Category
Vascular
Structural class
Sedges
Detailed description
Rhizomatous, extensively creeping yellow-green to green sedge. Plants variable in size, usually flaccid, forming a matted sward. Rhizome long-creeping, to 2 mm diameter, covered by closely appressed brown scales or their fibrous remains; shoots ± distant, singly from the rhizome, c. 1 mm diameter at base including basal sheaths. Culms 20–450 × c. 0.5–1.0 mm, weak, smooth, green to yellow-green, obtusely trigonous; basal sheaths pale brown almost cream. Leaves < mature culms, 0.5–1.5 mm wide, channelled to flat, soft, grass-like, margins usually smooth or very minutely scabrid towards tip. Inflorescence a pale green or bright green ovate head, c. 10 mm long, of 2–5 closely packed ± sessile spikes, or occasionally 1–2 spikes distant from the rest; bracts subtending inflorescence and lower spikes green and leafy, much longer than inflorescence. Spikes androgynous, 4–8 mm long, male flowers 1–3 at base of spikes, occasionally 0. Glumes < utricles, ovate, acuminate, white or pale brown, with a green, faintly scabrid keel. Utricles 3.0–3.5 × c.1.5 mm, plano-convex, ovoid, elliptical, distinctly nerved on convex face, light greenish brown; narrowed to a scabrid beak c.1 mm long; stipe slightly > 0.5 mm long, pale cream. Stigmas 2. Nut c. 1.5 mm. long, plano-convex, broadly oblong, shortly stipitate, light to dark brown.
Similar taxa
Perhaps most similar to Carex colensoi Boott, from which it is distinguished by the shortly creeping, usually flaccid, trailing habit, and yellow-green to green rather than long trailing, light-green (almost glaucous) culms topped by 2–5 (rarely 1–2) pale green to light yellow-brown spikes rather than relatively large inflorescences composed of 1–4 clustered brown spikes. The utricles of C. inversa are prominently beaked and nerved; those of C. colensoi are scarcely beaked utricles and with indistinct nerves.
Distribution
Indigenous. New Zealand: North and South Islands
Habitat
Coastalt to montane - but mostly coastal to lowland. In scrub, open forest, and grassland. A common urban weed of lawns in northern New Zealand. This species has probably become more common as a result of human colonisation of the country.
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 | Not Threatened | Qualifiers: SO
Detailed taxonomy
Family
Synonyms
Carex smaragdina Col.
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Flowering
Throughout the year
Fruiting
Throughout the year
Life cycle and dispersal
Nuts surrounded by inflated utricles are dispersed by granivory and wind (Thorsen et al., 2009).
Propagation technique
Easily (too easily) grown from fresh seed and rooted pieces. An aggressive plant in most situations which readily spreads from seed and by detachment of the rhizome. This species is unlikely to be deliberately cultivated though it can be a useful ground cover in dry, open situations. Carex inversa is often spread by lawn mowers, and once established can prove difficult to control.
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
Where To Buy
Not commercially available.
Etymology
carex: Latin name for a species of sedge, now applied to the whole group.
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.
CARINV
Chromosome number
2n = c.40-44
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 | Not Threatened | Qualifiers: SO
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Regional conservation statuses
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 “Regional conservation status of indigenous vascular plants in Otago” Jarvie S et al. (2024) report.
Otago: 2024 | Regionally 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 for NZPCN 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 inversa Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/carex-inversa/ (Date website was queried)