Juncus effusus is a perennial herbaceous flowering plant species in the rush family Juncaceae, with the common names common rush or soft rush. In North America, the common name soft rush also refers to Juncus interior.
Juncus effusus grows in large clumps up to about 1.2 metres (3 ft 11 in) tall.[4]: 984 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.
Juncus effusus subsp. solutus (Fernald & Wiegand) Hämet-Ahti — central and eastern United States.[10]
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.[11]
Uses
Wildlife
The species provides wildfowl, wader feeding, and nesting habitats, and also habitats for small mammals. The rootstalks are eaten by muskrats, and birds take shelter amongst the plant's stems. A number of invertebrates feed on soft rush, including the rufous minor moth.[12]
Humans
Juncus effusus is one of the seven ingredients of hui sup tea (去濕茶).[citation needed] In Japan, this rush is called igusa (藺草) and is grown to be woven into the covering of tatami mats (the filling is rice straw, extruded styrofoam, chip board, or some combination).[13] In Iran and Afghanistan too it is used to weave light cheap mats.[citation needed] 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.
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.[14]
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 fertilizer (can pollute watersheds); and topping to prevent seed formation.
^Morton, J.K.; Venn, Joan. M. (2000). "The Flora of Manitoulin Island". University of Waterloo Biology Series N. 40. 3rd. edition.
^Niering, William A.; Olmstead, Nancy C. (1985) [1979]. The Audubon Society Field Guide to North American Wildflowers, Eastern Region. Knopf. p. 568. ISBN0-394-50432-1.
^"Structure of Tatami". Original Kyoto Tatami | Motoyama Tatami Shop | Original Kyoto Tatami Shop. Motoyama Tatami Shop. 2015-06-28. Retrieved 14 June 2021.
^Bhattacharyya (1980). "Structure of effusol: A new phenolic constituent from Juncus effusus". Experientia. 36: 27–28. doi:10.1007/bf02003949. S2CID41731083.
^Carvalho, CF; Sargent, MV; Stanojevic, E (1984). "Phenanthrene synthesis: The synthesis of effusol a 9,10-Dihydrophenanthrene from the marsh grass Juncus effusus". Australian Journal of Chemistry. 37 (10): 2111. doi:10.1071/CH9842111.
^Liao, You-Jiao; Zhai, Hai-Feng; Zhang, Bing; Duan, Tian-Xuan; Huang, Jian-Mei (2010). "Anxiolytic and Sedative Effects of Dehydroeffusol from Juncus effusus in Mice". Planta Medica. 77 (5): 416–20. doi:10.1055/s-0030-1250517. PMID21104609. S2CID260248394.