Setaria viridis (L.) Beauv. - Green Foxtail.
Synonym.Setaria weinmannii Roem. & Schult.
Green Bristle-Grass, Green Pigeongrass.
Systematic position.Family Poaceae (=Graminea), genus Setaria Beauv.
Biological group.Annual late spring weed.
Morphology and biology.Plant of 10-50 cm in height, branchy, multicaulis. The root system coronal, well advanced, penetrating into ground to 50 cm. Stalks upright, bare, rough under inflorescence. Leaf plates green, 2-12 mm in width; ligule ciliated. Inflorescence cylindrical, dense, 2-12 cm in length. Spikelets 2.5 mm in length, surrounded by long green or violet setae exceeding spikelets by 2 or 3 times. Shoots appear in April or May. Seeds sprout from depth of 10 cm. Blossoming and fructifying from July. Reproduction by seeds. One plant produces to 10-12 thousand seeds. The weight of 1000 seeds is less than 1 g. Seeds are spread by water, with manure, bird excrements, and to a lesser extent by wind. Seeds remain viable for 3 or 4 years, sprouting at temperatures of 15 to 20°C.
Distribution.Common weed and ruderal species in the entire territory of Russia (except for the Arctic areas). It is more abundant in the south of the country, occurring less often northward of forest-steppe zone, reaching northern border of agriculture lands.
Ecology.Grows on sandy and pebbling shores of reservoirs, on fallow lands and fields, along roads, in trash dump places at settlements. It is drought-resistant; abundant in rich soils.
Economic significance.Weed in fields; more often and abundant in tilled cultures, in irrigated lucerne; less often in grain crops, gardens, parks, vineyards, on plantations of subtropical cultures. Strongly dries up ground. Control measures include stubbling, harrowing, inter-row treatment of soil in tilled crops, chemical weeding.
Reference citations:Grin.ko N.I., Titov A.Kh., Kvartin V.N., Semernikova A.I., Lapchenkov G.YA., Dyatlenko V.A. 1987. Weed plants and its control in the Rostov Region. Manual. Persianovka: Donskoi SKHI. 102 p. (In Russian)
Gubanov I.A., Gubanov I.A., Kiseleva K.V., Novikov V.S., Tikhomirov V.N. 2002. The illustrated keys to plants of Middle Russia. Moscow: KMK. V. 1: 526. (In Russian)
Korchagina V.A., Penchukov V.M. Morozov N.A., Smashevskaya G.A., Kolomiitsev F.B., Trubeeva A.I., Baranova M.M. 1972. Control of weeds in the Far East. Khabarovsk: Khabarovskoe Publishing House. 18 p. (In Russian)
Nikitin V.V. 1983. Weed plants of the USSR flora. Leningrad: Nauka. 454 pp. (In Russian)
Ramenskii L.G., Tsatsenkin I.A., Chizhikov O.N., Antipin N.A. 1956. Ecological evaluation of the fodder lands by vegetation cover. Moscow: Selkohzgiz. 472 pp. (In Russian)