Rank Species | Genus Juncus Higher classification Juncus | |
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Similar Juncus, Common water hya, Rushes, Rattan, Willow | ||
Soft rush juncus effusus
Juncus effusus, with the common names common rush or soft rush, is a perennial herbaceous flowering plant species in the family Juncaceae. In North America the common name soft rush also refers to Juncus interior.
Contents
- Soft rush juncus effusus
- How to identify soft rush juncus effusus
- Distribution
- Description
- Subspecies
- Wildlife
- Humans
- Cultivation
- Weed control
- References
How to identify soft rush juncus effusus
Distribution
Juncus effusus is nearly cosmopolitan, considered native in Europe, Asia, Africa, North America, and South America. It has naturalized in Australia, Madagascar, and various oceanic islands.
It is found growing in wet areas, such as wetlands, riparian areas, and marshes. In the United Kingdom it is found in purple moor-grass and rush pastures and fen-meadow plant associations.
Description
Juncus effusus grows in large clumps about 1.5 metres (4 ft 11 in) tall at the water's edge along streams and ditches, but can be invasive anywhere with moist soil. It is commonly found growing in humus-rich areas like marshes, ditches, fens, and beaver dams.
The stems are smooth cylinders with light pith filling. The yellowish inflorescence appears to emerge from one side of the stem about 20 centimetres (8 in) from the top. In fact the stem ends there; the top part is the bract, that continues with only a slight colour-band marking it from the stem. The lower leaves are reduced to a brown sheath at the bottom of the stem.
Subspecies
Five subspecies are currently recognized:
- Juncus effusus subsp. austrocalifornicus Lint — endemic to California and Baja California.
- Juncus effusus subsp. effusus — widespread
- Juncus effusus subsp. laxus (Robyns & Tournay) Snogerup — tropical Africa, Madagascar, Mauritius, Canary Islands, Madeira.
- Juncus effusus subsp. pacificus (Fernald & Wiegand) Piper & Beattie — Alaska, British Columbia, Washington, Idaho, Oregon, California, Baja California.
- Juncus effusus subsp. solutus (Fernald & Wiegand) Hämet-Ahti — central and eastern United States.
Juncus effusus can be differentiated from the rarer Juncus pylaei by the number of ridges on the stem. Juncus effusus has 30 to 40 ridges and J. pylaei has 10 to 20.
Juncusol is a 9,10-dihydrophrenathrene found in J. effusus. The plant also contains effusol and dehydroeffusol.
Wildlife
The species provides wildfowl and wader feeding and nesting habitats, and also habitats for small mammals.
A number of invertebrates feed on soft rush, including the rufous minor moth.
Humans
In Japan, this rush is grown to be woven into the covering of tatami mats. In Hui sup tea, Juncus effusus is listed as one of the seven ingredients.
In Iran and Afghanistan too it is used to weave light cheap mat. It is called halfa (حلفا) and has medicinal uses too.
In Europe, this rush was once used to make rushlights (by soaking the pith in grease), a cheap alternative to candles.
Cultivation
The species is cultivated as an ornamental plant, for planting in water gardens, native plant and wildlife gardens, and for larger designed natural landscaping and habitat restoration projects.
The cultivar Juncus effusus 'Spiralis' (syn. Juncus spiralis), with the common names corkscrew rush or spiral rush, is a distinctive potted and water garden plant due to its very curled spiral like foliage.
Weed control
Juncus effusus can become a naturalized or invasive species, undesirable in rangelands for its unpalatability to livestock. Suggested methods of controlling rushes include: ploughing; high applications of inorganic fertiliser (can pollute watersheds); and topping to prevent seed formation.