The New Zealand Plant Conservation Network

Species

Trisetum drucei

Etymology

Trisetum: Three-bristled
drucei: after A.P. Druce, one of New Zealand's most respected field botanists

Common Name(s)

None known

Current Conservation Status

2012 - At Risk - Naturally Uncommon

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

2009 - At Risk - Naturally Uncommon
2004 - Sparse

Qualifiers

2012 - RR, Sp
2009 - DP

Authority

Trisetum drucei Edgar

Family

Poaceae

Flora Category

Vascular - Native

Structural Class

Grasses

Synonyms

None

Distribution

Endemic. North Island from Mt Wharekia, East Cape south to near Taihape. In the South Island in North West Nelson, and eastern Marlborough from the Waima River south to North Canterbury (Parnassus)

Habitat

A cliff dwelling species preferring calcareous mudstones, siltstones, sandstones, and marble and limestone. Occasionally on greywacke and ignimbrite rock. On these rocks it is usually found growing in seepages.

Features

Dense, tufted grass up to 600 mm with culms usually overtopping the dense, finely scabrid leaves; branching intravaginal. Leaf-sheath 20-80 mm, firmly membranous, grey-brown to light greenish brown, sometimes reddish, very densely minutely papillose or minutely scabrid to pubescent, rarely glabrous. Ligule 0.8-1 mm, truncate, erose, sparsely finely ciliate. Collar sometimes with a few stiff hairs up to 1.5 mm. Leaf blade 30-300 x 0.5-4 mm, dull green, glaucous or reddish, folded with inrolled margins or flat, firmly coriaceous, abaxially scabrid with dense prickle teeth, or smooth, or sparsely scabrid above, adaxially ribbed with minute prickle-teeth or densely pubescent on ribs; margins scabrid. Culm 100-400 mm, internodes glabrous or finely pubescent above, sometimes pilose, or minutely prickle-toothed below panicle. Panicle 50-200 x 10-30 mm, lanceolate, with short branches, more or less interrupted, not very dense, sometimes quite open; spikelets clustered and individual inconspicuous; rachis, branches and pedicels densely but minutely strigose or puberulous. Spikelets 6-8 mm, light green (often tinged reddish brown). Glumes unequal, membranous, keels with minute prickle-teeth in upper half; lower glume 3/4 of length of upper, narrow oblong to narrow ovate, upper glume 3/4 to almost equal the length of the spikelet, elliptic oblong; margins broadly hyaline, sparsely prickle-toothed near the acute, acuminate or rarely mucronate apex. Lemma 3.5-6 mm, bidentate or bicuspid, papillose, minutely prickle-toothed near midnerve; awn 3.5-7.5 mm, recurved, insertion in upper 1/4 of lemma. Palea minutely prickle-toothed on keels and on margins near apex. Callus hairs up to 1 mm. Rachilla hairs up to 2 mm. Lodicules 0.8-1.2 mm, glabrous. Anthers 0.8-2 mm. Ovary 0.8 mm; stigma styles 1.2 mm. Seed 2.5-3 x 0.7-0.8 mm.

Similar Taxa

A distinctive species usually inhabiting damp seepages on cliff faces. It is somewhat similar to Trisetum antarcticum (G.Forst.) Trin. in possessing intravaginal innovation shoots, and superficially similar in overall appearance to the more usually coastal T. arduanum Edgar et A.P.Druce. From both it differs through a combination of the having a dense tufted habit, more open, interrupted, though not very dense, lanceolate panicle, which is in turn shortly-branched throughout; and also by the leaf-blade which is densely to weakly, and always minutely, scabrid.

Flowering

October - February

Fruiting

December - May

Propagation Technique

Easy from fresh seed and rooted pieces but short-lived. A very attractive grass, with does best in a sunny aspect overlying damp soil

Threats

Not threatened but rather uncommon and sporadic in its distribution

Chromosome No.

2n = 28

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

This page last updated on 20 Jan 2014