Juncus microcephalus
Common name
South American rush
Family
Juncaceae
Flora category
Vascular – Exotic
Structural class
Rushes & Allied Plants
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.
JUNMIC
Conservation status
Not applicable
Brief description
Upright leafy rush to 90 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 heads of 4 to 10 reddish brown flowers/capsules (fruit).
Distribution
Common throughout the North Island and northern South Island, usually lowland.
Habitat
Aquatic: Emergent.
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).
Features
Loosely or densely tufted perennial, bronze or occasionally red-purple at base. Stems 15-90 cm high, without internal transverse septa below inflorescence. Leaves terete or ± compressed, transversely-septate with septa usually evident externally. Inflorescence 6-24 cm long, very variable, open, much-branched, with 3-8-flowered clusters at ends of branches. Tepals 3-3.5 mm long, all ± equal, broad, acute. Stamens 6. Capsule 2.5-3.5 mm long, < to ± = tepals, broad, depressed at top, minutely mucronate, reddish-brown.
Similar taxa
Similar to other tubular septate leaved rushes, but is taller and stouter than most other species (except J. acutiflorus) and has flat topped casules with a mucronate tip.
Flowering
Spring to early summer
Flower colours
Brown
Fruiting
Summer to autumn
Life cycle
Seed dispersed by animals, water or contaminated machinery.
Year naturalised
1790
Origin
South America
Reason for introduction
Unknown, seed or soil contaminant.
Control techniques
Not controlled in New Zealand.
Etymology
juncus: From the Latin jungere ‘to tie or bind’, the stems of some species being used to make cord (Johnson and Smith)
Notes on taxonomy
Subgenus Juncus, Section Ozophyllum (Septati) Kirschner (2002: Juncaceae 2)
Attribution
Factsheet prepared by Paul Champion and Deborah Hofstra (NIWA). Features description from Healy and Edgar (1980).
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
Healy, A.J. (1982). Identification of weeds and clovers. New Zealand Weed and Pest Control Society Publication. Editorial Services Limited, Featherston. 299pp.
Kirschner, J. (compiler) (2002). Juncaceae 2: Juncus subg. Juncus, Species Plantarum: Flora of the World Part 7: 1-336.