Juncus caespiticius
Biostatus
Native
Category
Vascular
Structural class
Rushes & Allied Plants
Detailed description
Tufted, dark green to red-green perennial forming circular patches up to 100 mm diameter. Stems 80–450 × 1–2 mm. Leaves numerous, all basal, grass-like, > inflorescence. Flowers 3 mm long; outer tepals acute or acuminate, shorter than the inner, more membranous, subobtuse tepals. Stamens 6. Capsule more or less equal in length to tepals, obtuse, mucronate.
Similar taxa
Distinguished from J. planifolius R.Br., J. lomatophyllus Spreng., and J. dregeanus Kunth by the inflorescence which is usually a single, globose head, and by the broadly channelled leaves. Since the 1980s a very similar, bright green to yellow green-leaved rush with dark black globose inflorescences has colonised the west coast of the North Island, initially around the Waitakere Coast but now known as far north as Hokianga and possibly as far south as Wanganui. This rush was subsequently identified as Juncus sonderianus Buchenau.
Distribution
Indigenous. new Zealand: North Island, South Island. Present in Australia.
Habitat
Usually coastal. Growing in or near damp seepages, or on steep, damp cliff faces festooned with Austroblechnum banksii (Hook.f.) Gasper et V.A.O.Dittrich, Sonchus kirkii Hamlin, Marchantia macropora Mitt. and Nostoc. Very rarely in dune swales or around the margins of brackish lagoons and streams. Also recorded on rock bluffs up to 500 m a.s.l.
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, DPR, DPS, DPT, PD, SO
Threats
Declining in the North Island, and locally extinct in some regions but the reasons for the decline are not clear. Status in the South Island is uncertain.
Detailed taxonomy
Family
Juncaceae
Synonyms
Australojuncus caespiticius (E.Mey.) 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
September–January
Fruiting
October–July
Life cycle
Mucilaginous seeds are dispersed by attachment, wind and water (Thorsen et al., 2009).
Propagation technique
Easily grown from fresh seed. An interesting pot plant or species for a damp place within a rockery. Has considerable horticultural potential.
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]
OBL: Obligate Wetland
Almost always is a hydrophyte, rarely 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)
caespiticius: From the Latin caespes ‘tuft’ or ‘sod of turf’, meaning made of turf or turf-like
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.
JUNCAE
Previous conservation statuses
2017 | At Risk – Declining | Qualifiers: DP, SO
2012 | Not Threatened
2009 | Not Threatened
2004 | Not Threatened
Referencing and citations
References and further reading
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. https://doi.org/10.11646/phytotaxa.622.1.2.
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
Fact Sheet prepared for NZPCN by P.J. de Lange (1 September 2006). Description based on Moore & 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): Juncus caespiticius Fact Sheet (content continuously updated). New Zealand Plant Conservation Network. https://www.nzpcn.org.nz/flora/species/juncus-caespiticius/ (Date website was queried)