Machaerina articulata
Common names
jointed baumea, jointed twig rush
Biostatus
Native
Category
Vascular
Structural class
Sedges
Detailed description
Stout, perennial sedge of semi-aquatic and aquatic habitats. Rhizome 5–7 mm diameter, usually long and widely creeping and covered with numerous tightly imbricating bracts. Culms 0.8–2.0 m tall, 4–6 mm diameter, cylindrical, smooth; hollow except for transverse septa more less distinct externally in lower part of culm. Leaves ± = culms; lamina terete, with distinct transverse septa; apex subacute, pungent; sheaths very long; lowermost leaves reduced to long, chartaceous, grey or light brown, mucronate bracts. Panicle 120–300 mm long, pendulous, heavily branched; branchlets in fascicles from sheathing bracts; lowermost bract 60–200 mm long, with lamina septate like the leaves. Spikelets exceedingly numerous, 4–6 mm long, deep red-brown, 1–3-flowered, 1–2 flowers fertile, usually not necessarily the lowest. Glumes 4–7, ovate or ovate-lanceolate, acute or acuminate, scabrid at the back and on the keel, margins scabrid or with short cilia; lowermost 1-2 glumes empty. Nut 2.0 × 1.5 mm, trigonous, elliptical to obovoid, red-brown with paler thickened angles, very shortly stipitate, crowned by the cushion-like pyramidal style-base.
Similar taxa
Easily distinguished from all other Machaerina species by the terete, externally septate leaves. It has a superficial similarity to Eleocharis sphacelata R.Br. from which it differs by the taller, dark green leaves and taller, many-branched drooping paniculate rather than spicate inflorescence.
Distribution
Indigenous. Australia, New Zealand, New Caledonia and the New Hebrides. In New Zealand confined to the North Island where it is known from Te Paki south to the Manawatu River.
Habitat
Coastal to lowland (up to 380 m a.s.l.). A common emergent species of swampy lakes, ponds, stream and river margins. Also colonising the lag zone of peat bogs.
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
Cladium articulatum R.Br.; Baumea articulata (R.Br.) Blake
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Flowering
September–December
Fruiting
November–May (but fruits may be present throughout the year)
Life cycle and dispersal
Nuts are wind dispersed (Thorsen et al., 2009).
Propagation technique
Easily grown from fresh seed and by the division of whole plants. Best grown on the margin of a pond, lake or slow flowing stream. An attractive though rather large sedge which is best grown in a place where there is suitable space for it. Prefers full sun and does best when planted into water. However, it is also tolerant of dry soils and can be grown in most garden situations.
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
Etymology
articulata: Having joints, jointed
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.
MACATC
Chromosome number
2n = 24
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.
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 (8 September 2006). 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 articulata Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/machaerina-articulata/ (Date website was queried)