Juncus squarrosus
Environmental Weed (2024)
Common names
heath rush
Biostatus
Exotic
Category
Vascular
Structural class
Rushes & Allied Plants
Simplified description
Leafy rush to 35 cm tall, leaves wiry, mostly at the base of the plant, bending downwards just above the base, with flowerheads made up of a few clusters of 2 to 3 dark brown flowers/capsules (fruit).
Flower colours
Brown
Detailed description
Perennial, very dense coarse tufts (15) -25-35 cm high; roots thick, spreading. Stems stout, stiffly erect. Leaves many, usually all basal, c. ½ length of stems, wiry, very stiff, channelled, abruptly reflexed from just above very wide sheath. Inflorescence 2-8-(12) cm long, strict, with few unequal branches. Flowers in clusters of 2-3-(6) at ends of branches. Tepals 5-6 mm long, ± equal, dark chestnut-brown even in young flowers, tips subulate to acute. Stamens 6, Capsule c. 5 mm long, slightly < tepals, obovate, very shortly mucronate, yellow-brown to dark chestnut-brown.
Similar taxa
No other rush has the reflexed stiff wiry leaves and the large dark chestnut brown capsules.
Distribution
Scattered but local abundant from Wairarapa and South Island from Marlborough to Otago and also Stewart Island.
Habitat
Peaty and other low nutrient (acid) sites.
Conservation status
Not applicable
Detailed taxonomy
Family
Juncaceae
Synonyms
Leafy rush to 35 cm tall, leaves wiry, mostly at the base of the plant, bending downwards just above the base, with flowerheads made up of a few clusters of 2 to 3 dark brown flowers/capsules (fruit).
Taxonomic notes
Subgenus Agathyron, Section Steirochloa (Poiophylli) Kirschner (2002: Juncaceae 3)
Ecology
Flowering
Spring to early summer
Fruiting
Summer to autumn
Year naturalised
1970
Origin
Europe and North Africa
Reason for introduction
Unknown, seed or soil contaminant
Control techniques
Rarely controlled, but can be controlled manually, mechanically or herbicidally depending on situation, susceptible to grazing.
Life cycle and dispersal
Seed dispersed by animals, water or contaminated machinery.
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)
Environmental Weed (2024)
This plant is named in a list of 386 environmental weeds in New Zealand 2024 prepared by DOC. 759 candidate species were considered for inclusion on this new comprehensive list of environmental weeds in New Zealand. The species considered were drawn from published lists of weed species, lists of plants that must be reported or managed by law if observed, existing national and regional programmes and agreements for pest management, and species already managed by the Department of Conservation (DOC). Candidate species were then assessed to see if they were fully naturalised and whether they have more than minor impacts in natural ecosystems. Read the full report here.
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.
JUNSQU
Referencing and citations
References and further reading
Healy, A.J.; Edgar, E. (1980). Flora of New Zealand, Volume III. Adventive Cyperaceous, Petalous and Spathaceous Monocotyledons. Government Printer, Wellington. 220pp.
Johnson PN, Brooke PA (1989). Wetland plants in New Zealand. DSIR Field Guide, DSIR Publishing, Wellington. 319pp.
Johnson, A. T. and Smith, H. A (1986). Plant Names Simplified: Their pronunciation, derivation and meaning. Landsman Bookshop Ltd: Buckenhill, UK.
Champion et al (2012). Freshwater Pests of New Zealand. NIWA publication. http://www.niwa.co.nz/freshwater-and-estuaries/management-tools/identification-guides-and-fact-sheets/freshwater-pest-species
Kirschner, J. (compiler) (2002). Juncaceae 3: Juncus subg. Agathryon, Species Plantarum: Flora of the World Part 8: 1-192.
Healy, A.J. (1982). Identification of weeds and clovers. New Zealand Weed and Pest Control Society Publication. Editorial Services Limited, Featherston. 299pp.
Attribution
Facthseet prepared by Paul Champion and Deborah Hofstra (NIWA). Featured description from Healy and Edgar (1980).
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.