Cirsium


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Related to Cirsium: Cirsium arvense, melancholy thistle

Cirsium

 

a genus of plants of the family Compositae. The members of the genus are perennial (less frequently, biennial) herbs. The flowers are tubular, gathered in calathide heads with a fairly prickly sheath. The achenes have pappi of featherlike hairs. There are more than 200 species in the northern hemisphere; in the USSR there are 111 species. Some species of Cirsium are pernicious weeds, some are melliferous, and some are decorative. The term Cirsium is sometimes also used to describe other plants of the family Compositae that have prickly leaves and calathide heads.

The creeping thistle or Canada thistle (C. arvense) occurs throughout the USSR except the polar and mountain regions and the arid regions of Middle Asia. It is a perennial soboliferous weed and is difficult to eradicate. The plant has many forms (creeping thistle, bristly thistle, gray-felt thistle, and pale-scaled thistle), which cross-pollinate and yield numerous hybrids. The stem is 50–130 cm tall, branched on top, with an underground part of 10–30 cm. The leaves are sessile, constricted at the base, dentate or lobed, and prickly. The flowers are tubular, lilac, and unisexual; the inflorescence is an anthodium (calathide head). The plant propagates by means of seeds and also vegetatively. The achenes are small, naked, and slightly curved, with a pappus that falls away easily. The root system consists of a vertical root reaching 2–3 m (sometimes 5–9 m) into the soil and layers of lateral roots of the first and subsequent orders of propagation leading away from it. The roots are capable of giving off shoots or suckers. Even small pieces broken off the roots and grown will yield new plants. The weeds choke out crops, sharply reducing the harvest and lowering the quality. Means of control include correct crop rotation, early deep autumn plowing with preliminary fertilization, interrow treatment of tilled crops, the application of herbicides, and the destruction of the weed along roads and field boundaries; and in a fallow field, systematic cultivation according to the amount of creeping thistle growth.

I. G. DEIANOV

References in periodicals archive ?
For bacterial test organisms used for evaluation of antimicrobial activities of Cirsium arvensis were collected from Department of Biotechnology and Microbiology Lab of Medical College Mirpur.
The compounds: eriodictyol 7-O-[beta]-glucoside (C1), 6-hydroxyluteolin 7-O-[beta]-glucoside (C2), scutellarein 7-O-[beta]-glucoside (C3) and pedalitin (C4) were isolated from Cirsium palustre (L.
Abbreviations: ACACA, acetyl-CoA carboxylase or, ACTB, actin, beta; ALA, [alpha]-linolenic acid; CL Cirsium brevicaule A GRAY leaves; EI-MS, electron ionizationmass spectrometry; FA, fatty acid; FASN.
Durante el estudio se hicieron recolectas sucesivas en los hospederos abajo indicados, pero principalmente en Cirsium subcoriaceum, donde en la mayor parte de los muestreos se encontraron larvas, lo que hace suponer una posible asociacion entre el thrips y esta especie vegetal que le sirve, en todo caso, para llevar a cabo su ciclo de vida.
Especies de otros generos de asteraceas tambien han sido mencionadas por su toxicidad para el hombre y los animales; entre ellos destacan los siguientes: Ambrosia, Anthemis, Arnica, Artemisia, Aster, Baileya, Barkleyanthus, Bidens, Cirsium, Conyza, Chromolaena, Elephantopus, Geigeria, Gutierrezia, Haplopappus, Helenium, Iva, Lactuca, Leucanthemum, Ligularia, Lygodesmia, Mikania, Packera, Parthenium, Pittocaulon, Psacalium, Psilostrophe, Rudbeckia, Sigesbeckia, Solidago, Sommerfeltia, Sonchus, Tagetes, Tanacetum, Telanthophora, Tetradymia, Trixis, Vernonia, Zexmenia, etc.
iii) The Szelce Valley site is an unmowed part of a largely mowed, desiccated marshy meadow characterized by Cirsium palustre and tall grasses (Dactylis polygama, Calamagrostis arundinacea) and sedges (Carex spp.
09% were Cichorium intybus, Calotropis procera, Achyranthes aspera Cirsium arvense, Conyza ambigua, Cypreus rotundus, Chenopodium album, Chenopodium murale, Convolvulus arvensis, Oxalis corniculata, Cynodon dactylon, Dactyloctenium aegyptium and Rumex dentatus.
Accordingly Chenopodium album, Chenopodium murale, Convolvulus arvensis, Melilotus indica, Anagallis arvensis, Cirsium arvensis, Coronopus didymus, Lathyrus aphaca, Medicago polymorpha, Polygonum plebejum, Rumex dentatus, Gallium aparine, Cnicus arvensis, Ephedra spp.
La remocion del manto de hojarasca, activa los mecanismos de regeneracion natural de las especies, permitiendo el arribo de propagulos, generando microhabitats que toleran el establecimiento y colonizacion de diversas especies como Digitalis purpurea, Phytolacca bogotensis, Senecio madagascariensis, solanum nigrum, Alonsoa meridionalis, Miconia squamulosa, Rubus bogotensis, Pteridium aquilinum, Passiflora mollisima, Cirsium vulgare, Anthoxanthum odoratum y Pennisetum clandestinum, entre las mas representativas, activando el proceso de sucesion secundaria (Martinez & Garcia, 2007).