Juncus effusus

From Wikipedia, the free encyclopedia
Jump to: navigation, search
"Soft Rush" redirects here. In inland North America, this usually refers to Interior Rush (J. interior).

"Common Rush" redirects here.

Juncus effusus
Juncus effuses.jpg
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Monocots
(unranked): Commelinids
Order: Poales
Family: Juncaceae
Genus: Juncus
Species: J. effusus
Binomial name
Juncus effusus

Soft rush (Juncus effusus) is a member of the genus Juncus. Native to most continents, and hence also known as common rush, this plant is found growing in wet areas, such as the purple moor-grass and rush pastures and fen-meadow plant associations in the United Kingdom.


Pupal cases of Coleophora caespitiella on J. effusus.

It 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.

Distinction from other species[edit]

J. effusus can be differentiated from the rarer J. pylaei by the number of ridges on the stem. J. effusus has 30 to 40 ridges and J. pylaei has 10 to 20.[1]

Differentiation within the species[edit]

Juncus effusus is divided into no fewer than nine varieties, as listed by the USDA.[2] They include the following varieties: the 'lamp rush' varieties brunneus, decipiens, exiguus, gracilis, and solutus; 'common rush' varieties conglomeratus, effusus, and pylaei; and 'Pacific rush' pacificus. Many of these have overlapping distributions in the US.


Detail of flower
Juncus effusus - harilik luga Keilas.jpg

It is a common plant native in most temperate countries.


Juncus effusus f. spiralis (syn. J. spiralis; J. effusus 'Spiralis) or Corkscrew Rush (Spiral Rush) is a popular ornamental water plant due to its tortuous spiral like foliage.[3]

Control of rushes[edit]

Soft rush can become invasive because of its unpalatability to livestock. Suggested methods of controlling rushes are

  • Ploughing
  • Drainage
  • High applications of inorganic fertiliser, coupled with taking silage crops. However application of farm yard manure is ineffective
  • Topping, i.e. to prevent seed formation and distribution into the soil, followed by autumn or winter flooding for a week or two

Burning is ineffective because the plant remains green through the winter.

Environmental benefit[edit]

Wildfowl and wader feeding and nesting habitat, also a habitat to small mammals.

A number of invertebrates feed on soft rush, including the rufous minor moth


In Japan, this rush is grown to be woven into the covering of tatami mats.

In Europe, this rush was once used to make rushlights (by soaking the pith in grease), a cheap alternative to candles.

In hui sup tea, Juncus effusus is listed as one of the seven ingredients.


Juncusol is a 9,10-dihydrophrenathrene found in J. effusus.[4][5] The plant also contains effusol[6] and dehydroeffusol.[7]



  1. ^ Morton, J.K. and Venn, Joan. M. (2000). "The Flora of Manitoulin Island". University of Waterloo Biology Series n. 40. 3rd. edition. 
  2. ^ USDA PLANTS website
  3. ^ Heritage Perennials: Juncus effusus f. spiralis
  4. ^ Bhattacharyya,Experientia,36,(1980),27
  5. ^ Shima,Phytochem.,30,(1991),3149
  6. ^ Phenanthrene synthesis: The synthesis of effusol a 9,10-Dihydrophenanthrene from the marsh grass Juncus effusus. CF Carvalho, MV Sargent and E Stanojevic, Australian Journal of Chemistry, 1984, volume 37, issue 10, pages 2111-2117, doi:10.1071/CH9842111
  7. ^ Anxiolytic and Sedative Effects of Dehydroeffusol from Juncus effusus in Mice. You-Jiao Liao, Hai-Feng Zhai, Bing Zhang, Tian-Xuan Duan and Jian-Mei Huang, Planta Med., 2011, volume 77, pages 416–420, doi:10.1055/s-0030-1250517

General references[edit]

  1. Peter F.Zika (2003). "The native subspecies of Juncus effusus (Juncaceae) in western North America". Brittonia 55 (2): 150–156. doi:10.1663/0007-196X(2003)055[0150:TNSOJE]2.0.CO;2. JSTOR 3218455. 
  2. C. Michael Hogan, ed. 2010. Juncus effusus. Encyclopedia of Life.
  3. Cutting Rushes Article in Conservation Land Management Magazine, Spring 2003, see British Wildlife Publishing website for a copy

External links[edit]