Species

Poa tennantiana

Etymology

Poa: meadow grass
tennantiana: after Tennant, teacher and member of the 1907 expedition to the subantarctic islands

Common Name(s)

Muttonbird Poa

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 - Range Restricted

Qualifiers

2012 - RR

Authority

Poa tennantiana Petrie

Family

Poaceae

Flora Category

Vascular - Native

NVS Species Code

POATEN

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.

Structural Class

Grasses

Synonyms

Poa foliosa var. tennantiana (Petrie) Cheeseman

Distribution

Endemic. New Zealand: South (Otago (Taieri River Mouth), Stewart, Snares and Auckland Islands. It has not been seen on the Auckland Islands recently.

Habitat

Coastal usually in or near sea bird nesting grounds, on forest margins, clearings, in low scrub, on cliff faces and damp banks.

Features

Yellow-green, rather stout, stiff-leaved, perennial tussock-forming grass up to 1 m tall, arising from a strong rhizomatous base covered by abundant fibrous remnants of leaf-sheaths; branching intravaginal; leaf-blades persistent. Leaf-sheath submembranous, striate, densely, retrorsely, minutely pubescent-scabrid between ribs in basal leaves, glabrous in cauline leaves, very light brown, later becoming darker and shredding into fibres. Ligule 6-16 mm, apically glabrous, entire, narrowed to a long fine point, abaxially short-pubescent. Leaf-blade 160.0-380.0 x 4.5-9.0 mm, flat, finely striate, abaxially smooth, adaxially minutely papillose, very rarely minutely ciliate-scabrid on ribs; margins ciliate-fimbriate for a short distance above ligule, otherwise glabrous, gradually narrowed to straight-sided acute tip. Culm 150-330, internodes glabrous. Panicle 90-160 mm, broad, dense but much-branched, upper branches almost completely hidden by numerous, rather small spikelets, lower branches naked towards base; rachis smooth, branches and pedicels ¡¾ scabrid to occasionally smooth. Spikelets 3.5-4.5 mm, 2-3-flowered, light brown. Glumes subequal, ovate-lanceolate, acute, glabrous; lower 2.0-2.5 mm, 1-nerved, upper 2.5-3.0 mm, 3-nerved; midnerve near tip and margins with sparse prickle-teeth. Lemma 3.0-3.5 mm, 5-nerved, ovate-elliptic, minutely pubescent-scabrid, nerves longer ciliate on lower 1/3, acute, or midnerve very shortly excurrent. Palea 2.5-3.0 mm, keels scabrid in upper 1/2, interkeel smooth or with a few prickle-teeth. Callus glabrous. Rachilla c.0.5 mm, glabrous; prolongation twice as long. Lodicules 0.5-0.8 mm. Anthers 1.0-1.5 mm. Seed 1.5 x 0.5 mm.

Similar Taxa

Similar to Poa foliosa (Hook.f.) Hook.f. which is a superficially similar southern New Zealand robust grass of coastal areas, especially near sea bird nesting grounds. Poa tennantiana differs from P. foliosa by its monoecious rather than dioecious habit, yellow-green rather than green leaves, by the lower leaf-sheaths scabrid between the nerves, rather than smooth, and by the glabrous rather than hairy (hairs crinkly in a prominent tuft) callus

Flowering

October - December

Fruiting

November - April

Propagation Technique

Easily grown from fresh seed and rooted pieces. Dislikes humidity and will not flower or thrive in warm climates.

Threats

Not Threatened. Listed because it is a narrow range endemic of mainly offshore island. It is abundant in most of its known locations with no obvious threats.

Chromosome No.

2n = 56

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

Where To Buy

Not commercially available.


Attribution

Description modified from Edgar and Connor (2000).

References and further reading

Edgar, E.; Connor, H.E. 2000: Flora of New Zealand. Vol. V. Grasses. Christchurch, Manaaki Whenua Press. 650 pp.

This page last updated on 7 Jan 2014