Juncus conglomeratus
Common name
soft 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.
JUNCON
Conservation status
Not applicable
Brief description
Upright clump-forming leafless rush to 80 cm tall, with tall cylindrical stems, with tightly clustered spherical flowerheads near the end of each stem, made up of many red-brown flowers/capsules (fruit).
Distribution
Tasman to Southland.
Habitat
Lake margins, roadside drains and wet pasture.
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).
FACW: Facultative Wetland
Usually is a hydrophyte but occasionally found in uplands (non-wetlands).
Features
Erect clumps; rhizomes short. Stems 30-80 cm × 1.5-3 mm, soft and easily split, grey-green, dull, prominently ridged especially just below inflorescence, pith continuous, cobwebby. Basal sheaths brownish-red, not shining. Inflorescence a ± spherical head c. 1 cm long, base of subtending floral bract conspicuously red-tinged and expanded to a wide opening through which inflorescence emerges. Flowers very crowded. Tepals 2-2.5 mm long, ± equal, acuminate. Stamens 3. Capsule c. 2 mm long, ± = tepals, ovoid-oblong, flattened at top, reddish-brown.
Similar taxa
Similar to other tall leafless rushes, but has a dense single flower cluster, with an expanded floral bract behind it and conspicuous ridges on the stem beneath the inflorescence.
Flowering
Spring to early summer
Flower colours
Brown
Fruiting
Summer to autumn
Life cycle
Seed dispersed by animals, water or contaminated machinery.
Year naturalised
1930
Origin
Europe, Western Asia Northwestern Africa and North 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 Agathyron, Section Juncotypus (Genuini) Kirschner (2002: Juncaceae 3)
Attribution
Factsheet prepared by Paul Champion and Deborah Hofstra (NIWA). Feature 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 3: Juncus subg. Agathryon, Species Plantarum: Flora of the World Part 8: 1-192.