Flora-Fauna

Juncus effusus L.

(Sp. Pl.: 326; 1753 – Nouvelle Flore du Liban et de la Syrie, vol. 1, Pl. LX nº 1; 1966)

• Life-form & habit: Perennial rhizomatous rush forming dense tufts 30–120 cm tall. Rhizome short, creeping or oblique, much-branched. Culms erect, cylindrical, 1–4 mm thick, smooth and bright green when fresh, finely striate when dry, with a continuous pith — a key diagnostic feature of the species.

• Leaves: Reduced to basal sheaths, reddish-brown or straw-coloured, dull and tightly appressed around the stem base; true blades absent.

• Inflorescence & flowers: Pseudolateral panicle (appearing lateral but overtopped by a long bract resembling a stem continuation), loose to contracted, 5–25 cm, many-flowered. Flowers small (1–2 mm), greenish-brown; tepals subequal, lanceolate-acuminate, pale-brown with green midrib. Stamens 3; anthers linear, shorter than filaments. Capsule obovate-trigonal, shining, nearly equal to the perianth, 3-locular; seeds oblong, minute, yellowish-brown.

• Phenology: Flowers from April to June.

• Habitat & elevation: Moist or wet, non-calcareous soils — ditches, marshy meadows, and stream margins; from the coast up to c. 2 000 m.

• Lebanese distribution: Beirut (possibly adventive beneath conglomerates), Bikfaya, Qrayé, Nahr es-Safa, Mayrouba, between Sannine and Kneissé, Col de Zahlé, Falougha, Beskinta–Khan Sannine.

• Native range: Afghanistan, Alabama, Alaska, Albania, Algeria, Altay, Arizona, Arkansas, Assam, Austria, Azores, Baleares, Baltic States, Belarus, Belgium, Bolivia, British Columbia, Bulgaria, Burundi, California, Cambodia, Canary Is., Central European Russia, China North-Central, China South-Central, China Southeast, Colombia, Connecticut, Corse, Costa Rica, Cyprus, Czechia-Slovakia, Delaware, Denmark, District of Columbia, DR Congo, East Aegean Is., East European Russia, East Himalaya, Ecuador, El Salvador, Finland, Florida, France, Free State, Føroyar, Georgia, Germany, Great Britain, Greece, Guatemala, Haiti, Honduras, Hungary, Iceland, Idaho, Illinois, India, Indiana, Iowa, Iran, Iraq, Ireland, Italy, Kansas, Kentucky, Kenya, Krasnoyarsk, Kriti, Krym, Leeward Is., Louisiana, Madagascar, Madeira, Maine, Manchuria, Manitoba, Maryland, Massachusetts, Mauritius, Mexican Pacific Is., Mexico Central, Mexico Gulf, Mexico Northeast, Mexico Northwest, Mexico Southeast, Mexico Southwest, Michigan, Minnesota, Mississippi, Missouri, Montana, Morocco, Nebraska, Netherlands, New Brunswick, New Hampshire, New Jersey, New York, Newfoundland, North Carolina, North Caucasus, North European Russia, Northern Provinces, Northwest European Russia, Norway, Nova Scotia, NW. Balkan Pen., Ohio, Oklahoma, Ontario, Oregon, Palestine, Pennsylvania, Peru, Poland, Portugal, Prince Edward I., Québec, Rhode I., Romania, Rwanda, Sardegna, Sicilia, South Carolina, South European Russia, Spain, Svalbard, Sweden, Switzerland, Taiwan, Tanzania, Tennessee, Texas, Tibet, Transcaucasus, Tunisia, Türkiye, Türkiye-in-Europe, Uganda, Ukraine, Venezuela, Vermont, Virginia, Washington, West Himalaya, West Siberia, West Virginia, Wisconsin, Zimbabwe. Doubtfully present in: Ethiopia.

• Introduced range: Amsterdam–St. Paul Is., Cape Provinces, Colorado, Falkland Is., Hawaii, Irkutsk, Marion–Prince Edward Is., New South Wales, New Zealand North, New Zealand South, St. Helena, Tasmania, Tristan da Cunha, Victoria (POWO).

• ⚠️ Taxonomic note: Readily recognised by its smooth cylindrical stems with continuous pith (unlike the interrupted pith of Juncus inflexus) and its pseudolateral inflorescence; capsules obovate-trigonal, retuse at the apex. A characteristic wetland species widespread in the Levant.