The New Zealand Plant Conservation Network

Species

Pterostylis graminea

Etymology

Pterostylis: winged column
graminea: grassy

Common Name(s)

Grass-leaved Greenhood

Current Conservation Status

2012 - Not Threatened

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 - Not Threatened
2004 - Not Threatened

Authority

Pterostylis graminea Hook.f.

Family

Orchidaceae

Flora Category

Vascular - Native

NVS Species Code

PTEGRA

Structural Class

Orchids

Synonyms

None

Distribution

Endemic. North, South and Stewart Islands

Habitat

Coastal to montane (up ot 1000 m a.s.l.) mainly in indigenous forest, also in gumland scrub, peat bogs and within the more fertile lag zone of wetland margins. A variable species which in the current broad sense adopted by the New Zealand Flora series has no clear habitat preferences.

Features

Terrestrial, tuberous, glabrous, spring to summer-green perennial herb, mostly solitary or forming small patches of 3-5 plants through vegetative extension. Plant at flowering 10-330 mm tall. Stem erect, smooth, dark green, to reddish green, internodes < leaves. Leaves strictly erect, up to 4-6(-8), with entire margins, size changing from base to top of stem; the largest leaf on stem 80-150 x 5-10 mm, usually smaller, green to yellow-green, all linear-lanceolate, keeled with long-acuminate apices, widest near the sessile sheathing base, overtopping the flower. Flower solitary, usually tipping slightly forwards, small and delicate, front closely striped dark green and white, back of galea sparingly striped with green, mostly completely white. Ovary erect. Dorsal sepal 18-30 mm tall, erect then sharply horizontal, bearing few, widely spaced bands of green, the spacing of these widening toward rear to leave broad white bands or a completely white back; apex distinctly down-curved, acuminate to shortly caudate; lateral sepals diverging at a narrow angle, initially erect, apex curved to the front of galea, acuminate, shortly caudate, overtopping galea. Petals broad almost to apex, a little shorter than dorsal sepal. Labellum basally red otherwise greenish-brown or green with a distinctly darker apex; lamina oblong to narrowly oblong, slightly arched and then bend forward smoothly and symmetrically between the lateral sepals, flat in cross-section, with midrib only slightly prominent, and grading from weakly to completely indiscernible toward apex, apex emarginate. Column more or less tall as the labellum; stigma narrow, scarcely distinguished from column.

Similar Taxa

An extremely variable species which probably encompasses a number of distinct entities worthy of taxonomic recognition at some level. Pterostylis graminea is most likely to be confused with P. agathicola D.L.Jones, Molloy et M.A.Clem., which is endemic kauri (Agathis australis (D.Don.) Lindl.) dominated forests and differs by its fewer, drooping to almost horizontal, rather than erect leaves, which rarely overtop the flower; by the much longer, attentuated dorsal sepal that arches upwards; and by the usually reddish labellum which has a prominent raised midrib and a pinched in, somewhat twisted rather then more or less flat and emarginate apex. A form found in North Island lowland peat bogs is very similar to P. cernua D.L.Jones, Molloy et M.A.Clem.

Flowering

September - January

Flower Colours

Green,White

Fruiting

October - April

Propagation Technique

Difficult - should not be removed from the wild. Basic orchid mix consists of 2 parts medium coarse sand, ideally clean river sand; 2 parts soil, humus or leaf-mould; 1 part weathered sawdust or rotting wood; 1 part granulated bark. For Pterostylis shade of 50% and pots kept evenly moist.

Threats

Not Threatened

Chromosome No.

2n = 44

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

This page last updated on 31 Oct 2014