Weeds
Lappula patula (Lehm.) Menyharth - Margined Stickseed
Systematic position.
Family Boraginaceae, genus Lappula Moench.Synonym.
Echinospermum patulum Lehm.Biological group.
Annual weed.Morphology and biology.
Plant is 10-20 (50) cm tall; stems strong, upright, thinly hairy, grayish, branchy from the middle. Leaves are linear, 2-4 cm long and 1-3 mm wide; lower ones petiolate; other leaves sedentary, sparsely hairy. Flowers very small, aggregated in inflorescences-racemes at tips. Calyx reaches up to 2 mm long, its lobes lengthened and stellate-prostrate at fruits. Corolla blue; bell-shaped bend is about 2 mm in diameter. Nutlets are spherical-ovoid, bordered by one row of anchor-like spines reaching 2-2.5 mm in length. Blossoming occurs from April until August, fructifying from May until September.Distribution.
The species has mainly an Asian distribution area, but also grows in East Europe. In Russia it is distributed in the south of the European part (adventive in other places), in the Northern Caucasus, in Western Siberia and (adventive) in Eastern Siberia. In Central Asia it grows sporadically (adventive in all areas).Ecology.
The species is distributed in all southern droughty areas. It lives in dry and stony places, on slopes and taluses, along roads, at dwellings and among crops up to 1200 m above see level. It is founds in steppe and semi-desert zones more often, whence it has been brought into more southern areas of Central Asia where the weed grows sporadically in ruderal habitats. It spreads easily by human actvities, expanding its area.Economic significance.
The weed grows among crops of winter and spring wheat, oat, millet, and other cultures in all southern zones. In Central Asia it strongly litters wheat. The main control measure is stubbling by a disk harrow along with subsequent plowing.Reference citations:
Gubanov I.A., Kiseleva K.V., Novikov V.S., Tikhomirov V.N. 2004. The illustrated keys to plants of Middle Russia. V. 3. Moscow: KMK. 520 p. (In Russian)Keller B.A., ed. 1934. Weed plants of the USSR. V. 3. Leningrad: AN SSSR. 448 p. (In Russian)
Nikitin V.V. 1983. Weeds in the flora of the USSR. Leningrad: Nauka. 454 p. (In Russian)
Vasilchenko I.T., Pidotti O.A. 1975. Keys to weed plants of areas of irrigated agriculture. Leningrad: Kolos. 375 p. (In Russian)