Pterostylis graminea
Common names
grass-leaved greenhood
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Orchids
Flower colours
Green, White
Detailed description
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 × 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 to 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.
Distribution
Endemic. New Zealand: North Island, South Island, Stewart Island/Rakiura.
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.
Current conservation status
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2022-2023 using the New Zealand Threat Classification System (NZTCS) – more information about this can be found on the NZTCS website. This report includes replaces all previous NZTCS lists for vascular plants. Previous assessments can be found here.
Please note, threat classifications are often suggested by authors when publications fall between NZTCS assessment periods – these interim threat classification statuses has not been assessed by the NZTCS panel.
- Conservation status of vascular plants in Aotearoa New Zealand, 2023. 2024. Peter J. de Lange, Jane Gosden, Shannel P. Courtney, Alexander J. Fergus, John W. Barkla, Sarah M. Beadel, Paul D. Champion, Rowan Hindmarsh-Walls, Troy Makan and Pascale Michel Department of Conservation. Source: NZTCS and licensed by DOC for reuse under the Creative Commons Attribution 4.0 International licence.
2023 | Not Threatened
Detailed taxonomy
Family
Orchidaceae
Synonyms
None
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
September–January
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.
Other information
Etymology
pterostylis: Winged column
graminea: Grassy
Manaaki Whenua Online Interactive Key
NVS code
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.
PTEGRA
Chromosome number
2n = 44
Previous conservation statuses
2017 | Not Threatened
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Referencing and citations
References and further reading
Moore LB, Edgar E. 1970. Flora of New Zealand, Volume II. Indigenous Tracheophyta: Monocotyledones except Gramineae. Government Printer, Wellington, NZ. 354 p.
Attribution
Fact Sheet prepared for NZPCN by P.J. de Lange 14 April 2007: Description adapted from Moore and Edgar (1970).
Some of this factsheet information is derived from Flora of New Zealand Online and is used under a Creative Commons Attribution 3.0 New Zealand licence.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Pterostylis graminea Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/pterostylis-graminea/ (Date website was queried)