The New Zealand Plant Conservation Network

Species

Microlaena carsei

Etymology

Microlaena: small cover (outer scales of spikelet)

Current Conservation Status

2018 - Threatened - Nationally Endangered

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Previous Conservation Status

2012 - At Risk - Naturally Uncommon
2009 - At Risk - Naturally Uncommon
2004 - Sparse

Qualifiers

2012 - Sp
2009 - DP

Authority

Microlaena carsei Cheeseman

Family

Poaceae

Flora Category

Vascular - Native

Structural Class

Grasses

Synonyms

Microlaena avenacea var. carsei (Cheeseman) Zotov

Distribution

Endemic. North Island only from Te Paki south to Kerikeri and Waipoua, thence disjunct to Great Barrier Island

Habitat

Seemingly endemic to kauri (Agathis australis (D.Don) Lindl) dominated forest where it most usually found in damp, shaded hollows amongst tree roots and in shaded sites on the margins of fast flowing streams, and/or river banks. It is very easily overlooked.

Features

Shortly creeping, rhizomatous, tufted, narrowly-leaved perennial grass. Rhizomes short, branching extravaginal, cataphylls 10-20 mm, bases swollen, glossy, keeled, acute. Internodes elongated, slender, glossy, glabrous, distinctly straminaceous, apel to dark brown. Leaf-sheath glabrous, keel stout, margin membranous. Ligule 0.75-1 mm, triangular. Auricles 2, marginal hairs 1,5-2.5 mm. Leaf-blade 80-250 x 4-8 mm, glaucous green to green, keel stout; margins sharp, prickle-edged. Culm up to 600 mm laterally compressed, internodes longitudinally grooved, glabrous. Panicle 200-300 mm, narrow, slender, nodes close-set, branches appressed, erect, filiform, nodes shortly branched with numerous close-set spikelets, often with longer, naked branches below; rachis longitudinally grooved, rachis, branches and pedicles finely prickled. Spikelets 15-23 mm, numerous, solitary, on short or long pedicels. Glumes unequal, covering base fo spikelet, margins ciliate; lower 0.2-0.6 mm, 1-nerved, < callus hairs, upper 0.75-1.7 mm, 3-nerved, triangular acute or irregularly lobed to erose, > callus hairs. Lower steriel lemma 5-16 mm, 3-5-nerved, keel prickled edged and also above, otherwise smooth, undersides hairy, awn 1/2 lemma length, sometimes less than or equal lemma bearing perfect flowers, callus hairs 0.5 mm; upper sterile lemma 14-25 mm, 3-5-nerved, densely prickled-toothed on keels and above, smooth elsewhere, undersides hairy, awn 1/2 lemma length; callus hairs 1.5 mm, lemma bearing perfect flowers 5-10 mm, 3-5-nerved, awn 0-0.5 mm set between minute lobes, margisn ciliate above, apex deeply bifid (0.4-0.8 mm), ciliate. Stamens 2; anthers 1-2.2 mm, yellow. Ovary 0.65-75 mm; stigma-styles 1-2.2. mm, nude below. Seed 3-4 mm.

Similar Taxa

Microlaena avenacea (Raoul.) Hook.f. from which M. carsei differs by its shortly creeping rhizomatous habit, narrower leaves and panicles. The two species are sympatric throughout the known range of M. carsei.

Flowering

September - February

Flower Colours

Yellow

Fruiting

October - May

Propagation Technique

Easily grown from rooted pieces, from divisions of whole plants and from fresh seed. An attractive creeping, tufted grass that does best in partially shaded, moist soils.

Threats

Exact distribution is still unknown but most populations that are known about seem secure and are well portected within forest reserves. One population near Kerikeri is at risk from frequent flooding depositing silt on plants and also spreading weeds such as Tradescantia fluminensis Vell and Selaginella kraussiana (Kunze) A.Braun which are rapidly smothering this grass and other indigenous riparian species.

Chromosome No.

2n = 48

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

This page last updated on 19 May 2014