Poa billardierei
Common names
sand tussock, hinarepe
Biostatus
Native
Category
Vascular
Structural class
Grasses
Detailed description
Yellow-green tussocks up to about 70 cm tall. Leaves fine, rolled, somewhat drooping (coarser than silver tussock), initially green, often fading at tips to silver, and drying to golden-straw colour. Seed-heads no longer than leaves; seeds relatively large, barley-like, leaving a characteristic zig-zag look to the remaining head when fallen.
Similar taxa
Poa billardierei could be confused with Poa chathamica which has blue-green or grass-green flat leaves and an open seed head which overtops the foliage. It could also be confused with Ammophila arenaria (marram grass) which has similar foliage but large cat’stail-like seed heads that overtop the foliage. Ammophila arenaria is often confused with P. billardierei because they grow in the same habitat.
Distribution
North Island, South Island, Chatham Island (apparently absent from Chatham Island now despite being formerly abundant). Also found in temperate Australia.
Habitat
Coastal dunes; sandy and rocky places near the shore, especially foredunes and dune hollows.
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 | At Risk – Declining | Qualifiers: CI, DPS, DPT, PD, RR, SO
Threats
Mammalian grazing and browsing (palatable to sheep, cattle, goats and horses). Competition from marram grass. Coastal development and use of vehicles. The combined impact of browsing and competition from marram grass is believed to have caused the loss of the species from the Chatham Islands.
Detailed taxonomy
Family
Poaceae
Synonyms
Festuca littoralis Labill.; Schedonorus littoralis (Labill.) P.Beauv.; Triodia billardierei Spreng.; Poa billardierei (Spreng.)St.-Yves; Schedonorus billardiereanus Nees; Arundo triodioides Trin.; Schedonorus littoralis var. alpha minor Hook.f.; Austrofestuca littoralis (Labill.) E.B.Alexev.
Taxonomic notes
Until 2009 Poa billardierei was treated in Australasia as part of the segregate genus Austrofestuca Tzvelev. Soreng et al. (2009) reinstated the name Poa billardierei for this species after demonstrating that it and the allied Australian endemic Austrofestuca pubinervis (Vickery) B.K.Simon (now Poa pubinervis Vickery) were nested within Poa where they form their own section (Sect. Austrofestuca (Tzvelev) Soreng, L.J.Gillespie & S.W.L.Jacobs). The other two Australian endemic species of Austrofestuca (A. eriopoda (Vickery) S.W.L.Jacobs and A. hookeriana (F.Muell. ex Hook.f.) S.W.L.Jacobs are now placed in the reinstated Hookerochloa.
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Flowering
Early summer
Fruiting
Mid to late summer
Life cycle
Florets are wind dispersed (Thorsen et al., 2009).
Propagation technique
Collect seed in mid to late summer-autumn (early January in Wellington). Use fresh seed, sow in free-draining seed-raising mix (50:50 peat:sand), cover lightly with sieved river sand. It should germinate within 2 months. Grow on in open position where they will not be waterlogged. When growing by division collect matrial in autumn (after flowering has finished) or spring (before new growth appears). Use vigorous pieces from outside of plant and do not make divisions too small. Water regularly until established and new growth appears. Plant out in well-drained soil in open situation.
Other information
Plant of the Month
This plant has been featured as a Plant of the Month – see Trilepidea: NZPCN newsletter for May 2009 for the full story.
Etymology
poa: Meadow grass
billardierei: Named after Jacques Houttou de Labillardiere (1755-1834), 19th century French botanist who described several New Zealand plants
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.
POABIL
Chromosome number
2n = 28
Previous conservation statuses
2017 | At Risk – Declining | Qualifiers: PD, RR, SO
2012 | At Risk – Declining | Qualifiers: SO
2009 | At Risk – Declining | Qualifiers: SO
2004 | Gradual Decline
Referencing and citations
References and further reading
Cameron EK. 1991. Austrofestuca an extinct addition to the Waitakere Flora. Auckland Botanical Society Journal 46: 20.
Mitcalfe B, Horne C. 2002. Rediscovery of a nationally rare tussock in Makara Foreshore Reserve, Owhariu Bay, Wellington. Wellington Botanical Society Bulletin 48: 23–24.
Soreng RJ, Gillespie LJ, Jacobs SWL. 2009. Saxipoa and Sylvipoa – two new genera and a new classification for Australian Poa (Poaceae: Poinae). Australian Systematic Botany 22: 401-412.
Stanley, R. 2001. Sand tussock Austrofestuca littoralis update on the Auckland populations. Auckland Botanical Society Journal 56: 21–22.
Thorsen MJ, Dickinson KJM, Seddon PJ. 2009. Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285–309.
Attribution
Fact Sheet prepared for NZPCN by P.J. de Lange 2 September 2003.
NZPCN Fact Sheet citation
Please cite as: de Lange, P.J. (Year at time of access): Poa billardierei Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/poa-billardierei/ (Date website was queried)