Species

Juncus bulbosus

Etymology

Juncus: From the Latin jungere 'to tie or bind', the stems of some species being used to make cord (Johnson and Smith)

Common Name(s)

bulbous rush

Authority

Juncus bulbosus L.

Family

Juncaceae

Brief Description

Low-growing leafy rush to 25 cm tall (more than this in aquatic plants), leaves very fine, usually swollen at the leaf base, submerged leaves are fine and thread-like, up to 1 m long, plant often reddish with branched flowerheads made up of many small clusters of 2 to 6 yellow-brown flowers/capsules (fruit), but often clusters of leaves can be found on these flowers.

Flora Category

Vascular - Exotic

NVS Species Code

JUNBUL

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.

Structural Class

Rushes and Allied Plants

Distribution

Widespread and common throughout.

Habitat

Mostly peaty sites in wet pastures, water body margins, drains and wetlands, sometimes submerged.

Features

Low-growing, variable perennial rush, 5-15 cm high, densely tufted or with prostrate rooting stems with leafy tufts at nodes, often mat-forming or submerged. Stems usually reddish-tinged, slender, swollen at base, rooting at nodes. Leaves tiny and bristle-like (narrow, grass-like on floating and submerged plants), with distinct hollow compartments separated by partitions. Seedhead terminal, variable, unbranched and few flowered or branched and open, occ with tufts of bristly leaves. Flowers tiny, green to brown. Seed capsules 2-3 mm long, yellowish-brown.

Similar Taxa

No other introduced rushes have the clumped filamentous leaves, swelling at the nodes, proliferous flower heads. In aquatic habitats the leaves are longer and more grass-like and may be confused with J. bufonis, but the stems swollen at the base and the septa (cross wall) visible in the leaves distinguish J. bulbosus from J. bufonis. The native Juncus novae-zelandiae is superficially similar but has black capsules and lacks the leafy proliferous heads.

Flowering

Spring to early summer

Flower Colours

Brown,Green

Fruiting

Summer to autumn

Year Naturalised

1896

Origin

Eurasia 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.

Life Cycle and Dispersal

Seed dispersed by animals, water or contaminated machinery.

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. 

This page last updated on 30 Jul 2014