Machaerina juncea
Common names
sedge, tussock swamp twig rush
Biostatus
Native
Category
Vascular
Structural class
Sedges
Detailed description
Tufted, rush-like, rhizomatous perennial. Rhizome 3–10 mm diameter, woody, usually shortly creeping, sometimes greatly elongated, covered with loose, papery, imbricate, light brown bracts. Culms 0.2–1.35 tall, 1.0–3.5 mm wide, arising in mostly short- spaced (crowded) tufts along rhizome, terete, rigid, erect, smooth, glaucous to glaucescent, with 1–2 distant nodes. Leaves all reduced to light brown or reddish sheathing bracts, the lowermost smaller, mucronate, the upper 1–3 longer, distant along the culm, usually dark brown at the orifice, with a small, sickle-shaped, laterally flattened mucro-like lamina up to 5 mm long. Inflorescence 25–100 mm long, stiff, erect, spike-like, sparingly branched, subtended by a much shorter sheathing bract. Spikelets not fascicled, 4–5 mm long, red-brown, 1–2-flowered, only the lowest flowers fertile. Glumes 4–5, oblong-lanceolate, acute, membranous, streaked with brown, scabrid on the keel and towards the tip. Nut 2.5–3.0 × c. 1.5 mm, oblong-ovoid, obscurely trigonous, dark brown to black, orange near the base, surface pitted, surmounted by the small, tumid, pubescent style-base.
Similar taxa
Easily distinguished from other New Zealand species of Machaerina by the leaves which are reduced to sheathing bracts and from M. tenax by the uppermost sheathing bracts distant along culm (rather than clustered at the stem base), each surmounted by a short, falcate lamina and also by the glumes not spreading (rather than spreading in M. tenax) as the fruit matures. Machaerina juncea is superficially similar to Apodasmia similis with which it often grows, and from which it is distinguished by the grey-green, red-green to orange-yellow stems bearing regularly spaced bract-like, sheathing dark brown or maroon-black leaves, and by the terminal, many-flowered, paniculate to fascicled male and female spikelets.
Distribution
Indigenous. New Zealand: Three Kings, North and South Islands but scarce south of the Bay of Plenty and Waikato, and very uncommon in the South Island where it known mostly from Nelson, Marlborough and North Westland, though it extends south into Otago.
Habitat
Coastal to lower montane. Locally common in damp sites in gum land, swamps, salt marshes, and also along lake margins and river estuaries.
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
Cladium junceum R.Br.; Lepidosperma colensoi Boeck.; Baumea juncea (R.Br.) Palla
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Flowering
October–December
Fruiting
Fruits may be found throughout the year
Propagation technique
Easily grown from rooted pieces and fresh seed. Rooted pieces establish best if first healed in within a potting medium of mostly untreated saw dust. Once established remarkably tolerant of drought. Does best when planted in full sun, in a permanently damp soil. Machaerina juncea is not fussy about soil fertility but does best in a slightly acidic soil. It is also tolerant of saline conditions and can be planted into salt marshes and along estuarine creeks and lagoons.
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]
FACW: Facultative Wetland
Usually is a hydrophyte but occasionally found in uplands (non-wetlands).
Other information
Etymology
juncea: Rush-like
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.
MACJUN
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
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 (16 February 2012). Description adapted from Moore & 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): Machaerina juncea Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/machaerina-juncea/ (Date website was queried)