Apera spica-venti (L). Beauv. Silky Bentgrass, Wind-Grass
Taxonomic position.Family Poaceae Barnhart (Graminea), genus Apera Adans.
Biological group.Annual; can be a winter plant.
Morphology and biology.Stalk reaches 20 to 100 cm in height. Root system fibrillose. Leaves linear, to 5 mm in width, rough on both sides; ligule reaches 6 mm in length, blunt, disrupted. Inflorescence is a panicle reaching 30 cm in length, having plenty of fine two-three-colored twigs. Twigs one-floral, green or lilac-tinged. Caryopsides ripen quickly, fall before harvesting of winter cereals, and litter arable layer of soil. Every plant produces up to 16,000 caryopsides. Fallen grains quickly germinate, especially in damp warm weather; germinate rapidly after autumn rains; and do not germinate at all in summer. They germinate better from the ground surface and do not germinate from depths more than 2 cm. Germination of seeds begins at temperature 5°C; optimum temperature of germination is 10 to 12°C. Seeds maintain germinating capacity for 6-7 years. Reproduction and propagation occur by seeds.
Distribution.Moderately warm countries of Eurasia and northern Africa, from whence it was brought to many other countries. All areas of the European part of Russia (except for Arctic regions), Ciscaucasia, East Transcaucasia, Western and Eastern Siberia, the South of the Far East, Central Asia (the Aral-Caspian region).
Ecology.Prefers sandy and loamy sandy soils, damp habitats. It is distributed mainly in the Non-Chernozem zone, seldom found to the south.
Economic significance.Widespread pernicious weed in the past. Now a burdensome weed in winter crops, especially rye. The main control measures include correct system of soil treatment in multiple-field crop rotation together with bare and full fallows; cleaning of seed material.
Reference citations:Nikitin V.V. 1983. Weed plants of the USSR flora. Leningrad: Nauka. P. 96 (in Russian).
Simonov I. Weed plants and their control. Sverdlovsk: Sredne-Ural.skoe knizhnoe izdatel.stvo, 1969. P. 53 (in Russian).
Ul.yanova T.N. 1998. Weed plants in flora of Russia and CIS other countries. Saint Petersburg: VIR, p. 193 (in Russian).
Chesalin G.A. 1975. Weed plants and their control. Moscow: Kolos. p. 28-29 (in Russian).