Juncus pauciflorus
Common names
leafless rush
Biostatus
Native
Category
Vascular
Structural class
Rushes & Allied Plants
Flower colours
Brown, Green
Detailed description
Slender, clumps with sprawling to almost lianoid stems spreading widely from base. Rhizome 2–3 mm diameter, horizontal, near surface or above ground, easily pulled from soil. Flowering stems 0.25–1.00 m long, 0.75–2.00 mm diameter, bright green to reddish green, smooth, glossy to lustrous, internal pith continuous; leaves absent; basal bracts very short, conspicuously dark red-brown, closely sheathing. Inflorescence apparently lateral, rather lax and open, with flowers evenly spaced, often rather remote, on slender, flexible, more or less curved branchlets. Flowers 2.5–3.0 mm long; tepals light greenish brown. Stamens 6. Capsule 2.5–3.5 mm long, usually distinctly > tepals, ovoid to almost oblong, light brown to red-brown, often very dark towards apex.
Similar taxa
The rather widely spreading, loose, almost floppy, lianoid, bright green stems and slender, flexible branchlets are especially distinctive. Because it has continuous pith and six stamens it usually keys out with J. pallidus R.Br., which is a very different, robust rush up to 2 m tall, with broad (3–8 mm diameter) erect, light green to glaucous, soft rather than wiry stems.
Distribution
.Indigenous. North, South and Stewart Islands. Present in Australia
Habitat
Coastal to lowland (often on northern offshore islands) in damp ground and hollows under light scrub, in pasture, on swamp margins, in dune swales under scrub or within coastal forest.
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 | Threatened – Nationally Vulnerable | Qualifiers: Sp, DPR, DPS, DPT, PF, SO
Threats
Rather uncommon
Detailed taxonomy
Family
Synonyms
Juncus gunnii Hook.f., J. pauciflorus var. gunnii (Hook.f.) Buch. Agathryon pauciflorum (R.Br.) Záveská Drábková & Proćków
Taxonomic notes
Proćków et al. (2023) proposed a taxonomic segregation of Juncus into six genera based on molecular and morphological evidence. Whilst it has long been recognised that the current circumscription of Juncus includes morphologically divergent taxa—reflected in the recognition of numerous subgenera and sections—the consensus view of the NZPCN website taxonomy subcommittee, taking into consideration advice from Australian Juncus expert Dr Karen Wilson (NSW Herbarium) and others in Europe is that the generic segregations proposed need further consideration and testing. Accordingly, it has been decided to maintain the current broad circumscription of Juncus, but to include all new names as synonyms in factsheets. We thank, in particular, Dr Wilson for her helpful comments.
Endemic taxon
No
Endemic genus
No
Endemic family
No
Ecology
Flowering
November–January
Fruiting
November–April
Life cycle and dispersal
Mucilaginous seeds are dispersed by attachment, wind and water (Thorsen et al., 2009).
Propagation technique
Easy from fresh seed. Can be grown from rooted pieces and by the division of whole plants but resents root disturbance.
Wetland plant indicator status rating
Information derived from the revised national wetland plant list prepared to assist councils in delineating and monitoring wetlands (Clarkson et al., 2021 Manaaki Whenua – Landcare Research Contract Report LC3975 for Hawke’s Bay Regional Council). The national plant list categorises plants by the extent to which they are found in wetlands and not ‘drylands’. The indicator status ratings are OBL (obligate wetland), FACW (facultative wetland), FAC (facultative), FACU (facultative upland), and UPL (obligate upland). If you have suggestions for the Wetland Indicator Status Rating, please contact: [Enable JavaScript to view protected content]
FACW: Facultative Wetland
Usually is a hydrophyte but occasionally found in uplands (non-wetlands).
Other information
Etymology
juncus: From the Latin jungere ‘to tie or bind’, the stems of some species being used to make cord (Johnson and Smith)
pauciflorus: Few flowers
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.
JUNPAU
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 | Threatened – Nationally Vulnerable | Qualifiers: DP, SO, Sp
2012 | Threatened – Nationally Vulnerable | Qualifiers: DP, SO, Sp
2009 | At Risk – Declining | Qualifiers: DP, SO, Sp
2004 | Not Threatened
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 | Threatened – Regionally Critical | Qualifiers: DPR, DPS, DPT, Sp
Referencing and citations
References and further reading
Johnson, A.T. and Smith, H.A. 1986: Plant Names Simplified: Their pronunciation, derivation and meaning. Landsman Bookshop Ltd: Buckenhill, UK.
Moore, L.B.; Edgar, E. 1970: Flora of New Zealand. Vol. I. Government Printer, Wellington.
Proćków, J., Záveská Drábková, L. 2023. A revision of the Juncaceae with delimitation of six new genera: nomenclatural changes in Juncus. Phytotaxa 622(1): 17–41.
Thorsen, M.J.; Dickinson, K.J.M.; Seddon, P.J. 2009: Seed dispersal systems in the New Zealand flora. Perspectives in Plant Ecology, Evolution and Systematics 11: 285-309.
Attribution
Moore, L.B.; Edgar, E. 1970: Flora of New Zealand. Vol. I. Government Printer, Wellington.