Juncus articulatus
NPPA pest plant
Common names
jointed rush
Biostatus
Exotic
Category
Vascular
Structural class
Rushes & Allied Plants
Simplified description
Sprawling leafy rush to 80 cm tall, leaves round with internal cross walls (feels like clicks if you hold base of leaf between finger and thumb and slide up), plant with branched flowerheads made up of many small clusters of 4 to 8 dark purple to black flowers/capsules (fruit).
Flower colours
Black, Brown
Detailed description
Extremely variable perennial rush, 6-60 cm tall, dark green, usually reddish-tinged, loosely or densely tufted or forming open colonies. Stems round, rarely erect, usually flatter or prostrate and rooting at nodes, occ floating. Rhizomes usually short, occ long and forming mats. Leaves mostly along the stems, 5-20 cm long, round or compressed, with distinct hollow compartments separated by partitions (joints) usually visible externally and obvious to touch. Seedhead a loose panicle, terminal, 1-15 cm long, with many branches and clusters of small dark brown flowers. Seed capsules 2-4 mm long, triangular, glossy, dark brown to black.
Similar taxa
Similar to other tubular septate leaved rushes, but is often sprawling or ascending rather than upright, with acute-tipped dark brown to black capsules longer than the tepals.
Distribution
Widespread and common throughout.
Habitat
Margins of flowing and still water bodies, drains and wet pasture, sometimes submerged or floating.
Conservation status
Not applicable
Detailed taxonomy
Family
Taxonomic notes
Subgenus Juncus, Section Ozophyllum (Septati) Kirschner (2002: Juncaceae 2)
Ecology
Flowering
Summer
Fruiting
Autumn
Year naturalised
1864
Origin
Eurasia, North Africa and North America
Reason for introduction
Unknown, seed or soil contaminant.
Control techniques
Rarely controlled, but can be controlled manually, mechanically or herbicidally depending on situation.
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)
National Pest Plant Accord species
This plant is listed in the 2020 National Pest Plant Accord. The National Pest Plant Accord (NPPA) is an agreement to prevent the sale and/or distribution of specified pest plants where either formal or casual horticultural trade is the most significant way of spreading the plant in New Zealand. For up to date information and an electronic copy of the 2020 Pest Plant Accord manual (including plant information and images) visit the MPI website.
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.
JUNART
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 2: Juncus subg. Juncus, Species Plantarum: Flora of the World Part 7: 1-336.
Healy, A.J. (1982). Identification of weeds and clovers. New Zealand Weed and Pest Control Society Publication. Editorial Services Limited, Featherston. 299pp.
Attribution
Factsheet prepared by Paul Champion and Deborah Hofstra (NIWA).