Weeds
Stellaria media (L.) Vill. - Common chickweed.
Systematic position.
Family Caryophyllaceae Juss., genus Stellaria L. Synonyms : Alsinula media (L.) Dostal, Alsine media L.Biological group.
Annual or hardy-annual (facultative biennial), seed-propagated weed.Morphology and biology.
Root is thin, ramified. Stem is usually prostrate, 5-30 (40) cm long, round, one row of hairs, often twisting, developing roots at the nodes. Cotyledons are tender, light green, lanceolate, tapering into the petiole. Foliage leaves are opposite in pairs, small, pointed-ovate, tip often dot-shaped black, lower leaves petiolate, petioles with a comb of hair. Flowers are white, small, star-like, pedunculate, in terminal and in forks. Boll is ovate or oblong, longer than the calyx. Seeds are numerous, rounded or reniform, squeezed, brown. Seed germination depth is 1-2 cm. Seeds per plant: 15,000 (10,000-20,000). Seeds maintain their ability to germinate in soil for 2-5 years. Propagates with rooted stems as well. Germination period is from early spring until first autumn frosts. Yields 2-3 generations in a summer.Distribution.
Nearly cosmopolitan. Nearly all Europe and Asia, except Arctic regions, Northern America. Nearly all regions of the former USSR, except deserts of Central Asia.Ecology.
Likes good, friable, humus-rich, nitrogen-rich soils well-supplied with water. The minimum temperature for germination is +2-4°C, optimum +18-26°C.Economic significance.
One of the most widespread and extremely resistant weeds, especially in tilled crops, occurs in kitchen gardens, orchards, along roadways, near habitation. Control measures: harrowing before and after crop shoots emerge, early plowing, chemical weeding, stubbling.Reference citations:
Anonymous. 1996. Weeds on sugar beet. Berlin: Hoehst Schering AgrEvo GmbH. 396 pp. (In German, English, Russian, Ukrainian)Mal'tsev A.I. 1937. The atlas of the most important weed species of the USSR. Moscow-Leningrad: Selkhozgiz. V. 1: 52-54.
Nikitin V.V. 1983. Weed plants in the flora of the USSR. Leningrad: Nauka. 174 p.
Shishkin, B.K. 1936. Flora of the USSR. Moscow-Leningrad: Ac. Sc. USSR. V. 6: 395-396.