Cladium complanatum Bergg., Baumea complanata (Bergg.) Blake
Vascular – Native
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.
2n = c.50
Current conservation status
The threat classification status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2017 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website This report includes a statistical summary and brief notes on changes since 2012 and replaces all previous NZTCS lists for vascular plants. Authors: By Peter J. de Lange, Jeremy R. Rolfe, John W. Barkla, Shannel P. Courtney, Paul D. Champion, Leon R. Perrie, Sarah M. Beadel, Kerry A. Ford, Ilse Breitwieser, Ines Schönberger, Rowan Hindmarsh-Walls, Peter B. Heenan and Kate Ladley. Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – a suggested threat classification status has not been assessed by the NZTCS panel.
2017 | Threatened – Nationally Vulnerable | Qualifiers: RF
Previous conservation statuses
2012 | Threatened – Nationally Vulnerable | Qualifiers: RF
2009 | Threatened – Nationally Vulnerable | Qualifiers: RF
2004 | Range Restricted
Endemic. Known only from the North Island, where it now occurs locally from Te Paki south to the Kaipara Harbour. It was also once present in the Waikato on the shores of Lake Waaihi, and there are recent subfossil deposits made by this species in peat bogs (now drained) at Papamoa and Te Puke (Bay of Plenty)
Coastal to lowland (1-300 m a.s.l.). A species of open habitats which has been collected from estuaries (in salt marsh), consolidated dune swales (which are seasonally wet), freshwater lake and river margins, amongst gum land scrub, under regenerating kauri, from the margins of geothermally active springs and fumaroles, and from acidic peat bogs.
Wetland plant indicator status rating
FACW: Facultative Wetland
Usually is a hydrophyte but occasionally found in uplands (non-wetlands).
Dark green, tufted and leafy sedge. Culms 05–0.9(-1.3) m tall, c.3 mm wide, smooth, ± compressed. Leaves ± = culms, 4–8 mm wide, flat, distichous, isobilateral equitant, striated, pale green, tip acute, margins glabrous Panicle 0.15–0.50 m long, narrow, erect from a long sheath with short lamina; branchlets flexible, fascicled from upper sheaths. Spikelets, c.5 mm 1ong, light red-brown, 2–3-flowered, 1–2 flowers fertile. Glumes 5–6, ovate, acuminate or acute, chartaceous, striped with brown, scabrid on back towards tip, margins minutely ciliate. Nut, including beak, c.4 × 2 mm, trigonous, red-brown, very shortly stipitate, narrowed above to a long, triquetrous, scabrid beak
Machaerina sinclairii is similar but has much wider (10-30(-40) mm) light green (rather than dark green) leaves, some what fluffy brown more pendulous rather than erect to suberect, non-fluffy inflorescences, and the persistant style base of M. sinclairii is about the same length as the nut, and though rather narrow is quite conspicuous. In Machaerina complanata the style-base though persistant , is usually turgid, much shorter than the nut and usually inconspicuous.
September - November
November - March (but fruits of varying ages may be found throughout the year)
Difficult and should not be removed from the wild. Fresh seed germinates easily (usually within 1-3 months) but plants resent root disturbance and seedlings need to be handled with care as any root damage will kill them. Once seedlings establish it is easy to grow. Does well in wet or dry but prefers full sun. Experimentation with growing conditions at Oratia Native Plant Nurseries showed this species does best when planted in fresh, untreated pine saw dust. Seed set varies from year to year, and there is some indication that it has mast years. For example, 2005 was a particularly good seeding year, while the previous four years were not.
At all known sites seedlings are scarce (or absent altogether). Many populations are senescent or flower infrequently, and few are on protected land. Indications are that this is a light demanding plant which in the wild is succumbing to natural succession. In heavy shade plants will not flower. In the past this species was regarded as highly threatened, and at that time the key threat had been habitat loss caused by wetland drainage. Recent discoveries over the last 15 or so years indicate that this species is not necessarily confined to wetlands, and potentially can grow in any suitably open habitat.
complanata: Levelled or flattened
Fact sheet prepared for NZPCN by P.J. de Lange (8 September 2004). Description adapted from Moore & Edgar (1970).
References and further reading
Moore, L.B.; Edgar, E. 1970: Flora of New Zealand. Vol. II. Government Printer, Wellington.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Machaerina complanata Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/machaerina-complanata/ (Date website was queried)