Weeds
Xanthium spinosum L. - Spiny Cocklebur
Systematic position.
Family Asteraceae, genus Xanthium L.Synonyms.
Acanthoxanthium spinosum (L.) Fourr.Biological group.
Annual late spring weed.Morphology and biology.
Plant is 20-100 cm tall. Stem is straight, rigid, finely striated, simple or branchy, bristly pubescent. Leaves at base have straight, bifid or trifid glabrous yellow thorns. Leaves are short-petiolate, lanceolate or ellipsoid-lanceolate; upper leaves entire, other ones dentate or trilobate, less often irregularly pinnate-emarginated, with oblong pointed middle lobe and shorter lateral ones. Leaves green from above, with sparse decumbent bristly pubescence, with dense grayish bristly pubescence from below. Involucre enveloping hemicarp, ovoid or oblong, 10-13 mm long and 5 mm wide, with sparse bristly pubescence, covered with numerous thin hooked thorns almost to top, with one straight thin sharp subulate apical thorn that is 1 mm long. Blossoming occurs in June-July, fructifying in July-September. Spreading occurs by fruits catching on human clothes and animal hairs due to hooked thorns. Maximum fruitfulness of one plant is 4600 collective fruits. Fresh collective fruits only sprout in late spring the next year, from depths of no more than 18-20 cm.Distribution.
The European part of the former USSR, the Caucasus, Western Siberia, the Far East, Central Asia, Southern and Northern America, Antilles, Azores, Atlantic Europe, Middle Europe, Western and Eastern Mediterranean, Asia Minor, Southern Africa, Australia, New Zealand.Ecology.
The species inhabits waste grounds, garbage places, roadsides, river banks, ravines, fields, and pastures. This is a drought-resistant plant. It prefers sandy or clay, nutrient-rich soils, in sunny warm habitats.Economic significance.
The species is a malignant weed of grain and tilled cultures. Control measures include stubbling, autumn plowing, pre-seeding treatment of ground, inter-row treatments; if necessary, application of herbicides; maintenance of crop rotation; on uncultivated lands, weeds are cut during budding phase in order to prevent fructification.Reference citations:
Anonymous. 1996. Weeds on sugar beet. Berlin: Hoehst Shering AgrEvo Gmbh. 479 p. (In Russian)Dokuchaev V.M., ed. 1973. Green enemies. Weed plants of Stavropol. Territory and their control. Stavropol.: Stavropol. Publishing House. 167 p. (In Russian)
Keller B.A., Lyubimenko V.N., Maltsev A.I., Fedtshenko B.A., Shishkin B.K., Rodzevich R.Yu., Kamenskii K.V., eds. 1935. Weed plants of the USSR. V. 4. Moscow-Leningrad: AN USSR. 414 p. (In Russian)
Komarov, V.L., ed. 1959. Flora of the USSR. V. 25. Moscow-Leningrad: AN SSSR. 631 p. (In Russian)
Ulyanova T.N. 1998. Weeds in the flora of Russia and other CIS states. St. Petersburg: VIR. 233 p. (In Russian)