Juncus effusus var. effusus
Common names
soft rush
Synonyms
Agathryon effusum (L.) Záveská Drábková & Proćków
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.
JUNEVE
Conservation status
Not applicable
Simplified description
Upright clump-forming leafless rush to 1.2 tall, with tall, soft*, cylindrical stems, with continuous pith. The open clustered flowerheads near the end of each stem are made up of many light brown flowers/capsules (fruit). *Stems squash much more easily between thumb and fingers than most other ‘leafless’ rushes.
Distribution
Widespread and common throughout.
Habitat
Wet pasture and a wide range of wet habitats, including peaty areas.
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).
Detailed description
Dense tuft-forming rush with short rhizomes. Stems 30–120 cm × 1.5–3 mm, cylindrical, bright or yellow-green, softer than most similar spp, easily split or compressed, smooth, shining; with continuous, cobwebby pith. True leaves absent. Basal sheaths reddish-brown, closely held to stem. Seed head not at end of stem, with many tiny green flowers along short, downward-curving branchlets. Seed capsule 2–3 mm long, oval, light brown.
Similar taxa
Similar to other tall leafless rushes, but has an open inflorescence with the lower branches decumbent and cobwebby continuous pith in the stem. The soft, easily compressed and broken stems are distinct.
Flowering
Spring to early summer
Flower colours
Brown
Fruiting
Summer to autumn
Life cycle
Seed dispersed by animals, water or contaminated machinery.
Year naturalised
1864
Origin
Europe, Asia and 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.
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).
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.
Attribution
Factsheet prepared by Paul Champion and Deborah Hofstra (NIWA). Features 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.
References and further reading
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. 299 p.
Healy, A.J.; Edgar, E. (1980). Flora of New Zealand, Volume III. Adventive Cyperaceous, Petalous and Spathaceous Monocotyledons. Government Printer, Wellington. 220 p.
Johnson PN, Brooke PA (1989). Wetland plants in New Zealand. DSIR Field Guide, DSIR Publishing, Wellington. 319 p.
Johnson, A. T. and Smith, H. A. 1986. Plant Names Simplified: Their pronunciation, derivation and meaning. Landsman Bookshop Ltd, Buckenhill, UK.
Kirschner, J. (compiler) (2002). Juncaceae 3: Juncus subg. Agathryon, Species Plantarum: Flora of the World Part 8: 1–192.
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.