Lachnagrostis uda
Common names
swamp wind grass
Biostatus
Native – Endemic taxon
Category
Vascular
Structural class
Grasses
Detailed description
Perennial grass forming loose tufts 9–35 cm. Branching extravaginal. Leaf-sheath faintly ribbed, hairless, light green to dull brown. Ligule 1–2.5 mm, truncate or toothed, sparsely and finely scabrid (with teeth). Leaf-blade 3–10–(15) cm × 1–2 mm, flat or folded, smooth, undersides with sparse teeth on ribs, leaf margins sparsely scabrid, leaf tip obtuse. Culm 4–20 cm, often included within uppermost leaf-sheath, internodes finely scabrid below panicle. Panicle 3–14 × 1.5–8 cm, contracted at first, at maturity an open lax inflorescence. Spikelets (2.5–)3–3.5–(4) mm, pale green or tinged faint purple. Glumes equal, elliptic-lanceolate, midnerve and margins scabrid in upper ¼. Lemma 2–2.5 mm, ¾ length of glumes, with scattered soft hairs, rarely hairless, lateral nerves not evident, awn absent or if present straight, up to 2.5 mm. Anthers 0.7–1.3 mm. Callus hairs copious and conspicuous, covering ½–⅔ the lemma. Seed 1.2–1.8 × 0.5–0.6 mm.
Similar taxa
Allied to Lachnagrostis striata and L. lyallii. Differs from L. striata by the longer anthers (0.7–1.3 mm cf. 0.2–0.5 mm in L. striata). Differs from L. lyallii by the much shorter (to 2.5 mm cf. 2–6 mm), straight (rather than bent) awns. From both species, and all Lachnagrostis species (except L. glabra) it can be distinguished by the sparsely hairy lemma. It differs from L. glabra by the conspicuous callus hairs subtending the palea, and by the palea ½–⅔ the length of the lemma.
Distribution
Endemic to the South island. Known from scattered sites from south-western Canterbury, through central and western Otago. Probably more widespread than this as easily overlooked.
Habitat
An alpine to subalpine species of sedge-dominated wetlands.
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.
- 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 – Naturally Uncommon | Qualifiers: Sp, DPR, DPS, DPT, RR
Threats
Described in 1995. Lachnagrostis uda is probably not threatened but there are very few recent (>1980) collections.
Detailed taxonomy
Family
Synonyms
None
Endemic taxon
Yes
Endemic genus
No
Endemic family
No
Ecology
Flowering
No information available
Fruiting
No information available
Propagation technique
Easily grown by division and provided it is keep damp will grow readily. Dislikes warm, humid climates, and will not flower in these conditions. Easy from fresh seed.
Other information
Where To Buy
Not commercially available
Etymology
lachnagrostis: From “lachne” (wool) referring to the distinctive callus hairs of this genus and “agrostis” by which Trinius (1820) actually meant “a grass” (not an Agrostis). So the generic name means “a hairy (woolly) grass” not “a hairy (woolly) Agrostis” as is often incorrectly stated (see Gardner 2014).
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.
LACUDA
Chromosome number
2n = 98
Previous conservation statuses
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.
- 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.
2017 | At Risk – Naturally Uncommon | Qualifiers: DP, RR, Sp
2012 | At Risk – Naturally Uncommon | Qualifiers: RR, Sp
2009 | At Risk – Naturally Uncommon
2004 | Data Deficient
Regional conservation statuses
The regional threat classification system leverages off the national assessments in the NZTCS, providing information relevant for the regional context. Otago conservation status information is sourced from the “Regional conservation status of indigenous vascular plants in Otago” Jarvie S et al. (2024) report.
Otago: 2024 | At Risk – Regionally Naturally Uncommon | Qualifiers: DPR, DPS, DPT, NS, NStr, RR, Sp, St
Referencing and citations
References and further reading
Edgar E, Connor HE. 2000. Flora of New Zealand. Vol. V. Grasses. Manaaki Whenua Press, Christchurch, NZ. 650 p.
Attribution
Description modified from Edgar and Connor (2000).
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.