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Numerous variants of Cirsium arvense have been named based upon such features as pubescence, extent of leaf division, and spininess. Although extreme variants can be strikingly different, they are connected by such a web of intermediates that there seems to be little value in according any of them formal taxonomic recognition.
Canada thistle is a perennial introduced forb. It is distinguished from other thistles by creeping horizontal lateral roots, dense clonal growth, and dioecious habit [49,121,240]. Descriptions and terminology of Canada thistle biology can be confusing or contradictory. For example, descriptions of leaf morphology, stem height, and number of flowering heads may differ somewhat between floras. The following discussion provides ranges of what may be encountered for these characteristics, which will vary under different field conditions. Donald [55] and Moore [150] provide comprehensive reviews of the biology of Canada thistle.
Canada thistle has a deep and wide-spreading root system with a slender taproot and far-creeping lateral roots. It often forms large patches, and individual clones may reach 115 feet (35 m) in diameter [55,75,126,186,248]. Most Canada thistle roots are in the top 0.7 to 2 feet (0.2-0.6 m) of soil, but roots can extend as deep as 6.5 to 22 feet (2-6.75 m) [113,152,157]. Carbohydrate reserves are stored in roots and can range from 3% of root fresh weight during spring to as high as 26% in late fall [137]. Roots are injured when directly exposed to freezing temperatures for 2 hours at -5 °C and killed after 2 hours at -7 °C [192]. Arbuscular mycorrhizal infection of Canada thistle roots has been observed in several studies [17,50,116]. Canada thistle does not form rhizomes, despite this assertion in some literature. Adventitious root buds that may form new adventitious shoots can develop along the root at any location, and at any time of the year with favorable growing conditions [55,85]. New plants can also form from root fragments as short as 0.2 inch (6 mm) [157]. Soil type, structure and horizonation may impact the anatomy, morphology and distribution of Canada thistle roots as well. This suggests that root morphology and distribution are site specific and greenhouse studies of root morphology may not apply [55].
Canada thistle has slender aerial shoots with leafy stems reaching 1 to 6.5 feet (0.3-2 m) tall [42,81,84,176,238]. Leaves are 1.2 to 7 inches (3-18 cm) long and 0.2 to 2.4 inches (0.5-6 cm) wide [81,134,238]. Canada thistle leaf morphology (texture, hairiness, lobing and spininess) can vary considerably, even within a geographical region [84,150]. Canada thistle has numerous aboveground branches that bear several, small flowerheads (0.4 to 0.75 inch (1-2 cm) in diameter) in clusters [49,81,121,126,176,240]. Seeds are 0.09 to 0.2 inch (2.4-5 mm) long, and 0.04 inch (1 mm) in diameter with a pappus of feathery bristles [42,75,176,238,240].
While allelopathy has not been conclusively demonstrated for Canada thistle, this species may produce phytotoxins that inhibit the growth of other plants [55,203]. Fructan metabolism in Canada thistle adds to its competitive advantages by allowing it to grow at relatively cool temperatures [37].
Canada thistle is native to southeastern Europe and the eastern Mediterranean area, and was probably introduced to North America in the 1600s as a contaminant of crop seed and/or ship's ballast [152]. It is probably the most widespread of all thistle species [152]. In addition to North America, Canada thistle is invasive in northern and southern Africa, the Middle East, Japan, India, New Zealand, Australia, and South America. It infests at least 27 crops in 37 countries and thrives in temperate regions of the northern hemisphere [146]. In North America, Canada thistle occurs from Alaska east to the Northwest Territories, Quebec, and Newfoundland and south to California, New Mexico, Kansas, Arkansas, and North Carolina [107]. The PLANTS database provides a map of Canada thistle's distribution in the United States.
Canada thistle has been identified as a management problem in many national parks and on The Nature Conservancy preserves in the upper Midwest, the Great Plains states, and the Pacific Northwest [214]. It is an invader in Mesa Verde National Park, Colorado [67], Yellowstone National Park, Wyoming [4,48,218], Wood Buffalo National Park, Northwest Territories, Canada [83,237], Theodore Roosevelt National Park, North Dakota [32], and the Camas Swale Research Natural Area in the Willamette Valley, Oregon [43].
Although Canada thistle is not usually found in undisturbed forested areas, it has the potential to colonize a wide variety of forest habitats within its range following overstory removal and soil disturbance. The following listings take this potential into account.
Canada thistle is adapted to both survive fire on site, and to colonize recently burned sites with exposed bare soil. The extensive root system gives it the ability to survive major disturbances as observed, for example, at Mt. St. Helens, where Canada thistle was part of the initial community after the 1980 eruption. It survived landslide and resprouted from root and stem fragments after the blast [2,45,216]. It is likely to survive fire and sprout vegetatively from its extensive perennial root system (see Asexual reproduction), as was observed, for example, after an August wildfire in Mesa Verde National Park [64,67]. Additionally, there are numerous examples from the literature where Canada thistle seedlings established anywhere from 2 to 9 years after fire [3,56,122,138,158,190,219,242], presumably from wind-dispersed seed, although this is not always clear in the literature.
FIRE REGIMES: Canada thistle may change the fire ecology of the site in which it occurs by its abundant, flammable aboveground biomass. For example, in boreal wet-meadows, investigators suggest that Canada thistle has the potential to increase fire frequency and perhaps severity as a result of its abundant and readily ignited litter [100].
The following table provides some historic fire return intervals for habitats in which Canada thistle may occur. Find further fire regime information for the plant communities in which this species may occur by entering the species name in the FEIS home page under "Find FIRE REGIMES".
Community or Ecosystem Dominant Species Fire Return Interval Range (years) silver fir-Douglas-fir Abies amabilis-Pseudotsuga menziesii var. menziesii > 200 grand fir A. grandis 35-200 [9] maple-beech-birch Acer-Fagus-Betula > 1000 silver maple-American elm A. saccharinum-Ulmus americana sugar maple A. s. > 1000 sugar maple-basswood A. s.-Tilia americana > 1000 [233] bluestem prairie Andropogon gerardii var. gerardii-Schizachyrium scoparium 118,168] Nebraska sandhills prairie A. g. var. paucipilus-S. s. bluestem-Sacahuista prairie A. littoralis-Spartina spartinae sagebrush steppe Artemisia tridentata/Pseudoroegneria spicata 20-70 [168] basin big sagebrush A. t. var. tridentata 12-43 [191] mountain big sagebrush A. t. var. vaseyana 20-60 [10,30] Wyoming big sagebrush A. t. var. wyomingensis 10-70 (40**) [231,251] coastal sagebrush A. californica plains grasslands Bouteloua spp. blue grama-needle-and-thread grass-western wheatgrass B. gracilis-Hesperostipa comata-Pascopyrum smithii blue grama-buffalo grass B. g.-Buchloe dactyloides cheatgrass Bromus tectorum California montane chaparral Ceanothus and/or Arctostaphylos spp. 50-100 [168] sugarberry-America elm-green ash Celtis laevigata-Ulmus americana-Fraxinus pennsylvanica 233] curlleaf mountain-mahogany* Cercocarpus ledifolius 13-1000 [11,195] mountain-mahogany-Gambel oak scrub C. l.-Quercus gambelii northern cordgrass prairie Distichlis spicata-Spartina spp. 1-3 [168] beech-sugar maple Fagus spp.-Acer saccharum > 1000 [233] California steppe Festuca-Danthonia spp. 168] black ash Fraxinus nigra 233] juniper-oak savanna Juniperus ashei-Quercus virginiana Ashe juniper J. a. western juniper J. occidentalis 20-70 Rocky Mountain juniper J. scopulorum tamarack Larix laricina 35-200 [168] western larch L. occidentalis 25-100 [9] yellow-poplar Liriodendron tulipifera 233] wheatgrass plains grasslands Pascopyrum smithii 168] Great Lakes spruce-fir Picea-Abies spp. 35 to > 200 northeastern spruce-fir P.-A. spp. 35-200 [57] Engelmann spruce-subalpine fir P. engelmannii-A. lasiocarpa 35 to > 200 [9] black spruce P. mariana 35-200 conifer bog* P. m.-Larix laricina 35-200 [57] blue spruce* P. pungens 35-200 [9] red spruce* P. rubens 35-200 [57] pine-cypress forest Pinus-Cupressus spp. 9] pinyon-juniper P.-Juniperus spp. 168] whitebark pine* P. albicaulis 50-200 [9] jack pine P. banksiana 57] Rocky Mountain lodgepole pine* P. contorta var. latifolia 25-300+ [8,9,187] Sierra lodgepole pine* P. c. var. murrayana 35-200 [9] shortleaf pine P. echinata 2-15 shortleaf pine-oak P. e.-Quercus spp. 233] Colorado pinyon P. edulis 10-49 [168] South Florida slash pine P. elliottii var. densa 1-5 [156,233] Jeffrey pine P. jeffreyi 5-30 western white pine* P. monticola 50-200 Pacific ponderosa pine* P. ponderosa var. ponderosa 1-47 interior ponderosa pine* P. p. var. scopulorum 2-10 Arizona pine P. p. var. arizonica 2-10 [9] Table Mountain pine P. pungens 233] red pine (Great Lakes region) P. resinosa 10-200 (10**) [57,72] red-white-jack pine* P. r.-P. strobus-P. banksiana 10-300 [57,90] pitch pine P. rigida 6-25 [29,91] eastern white pine P. strobus 35-200 eastern white pine-eastern hemlock P. s.-Tsuga canadensis 35-200 eastern white pine-northern red oak-red maple P. s.-Quercus rubra-Acer rubrum 35-200 loblolly pine P. taeda 3-8 loblolly-shortleaf pine P. t.-P. echinata 10 to Virginia pine P. virginiana 10 to Virginia pine-oak P. v.-Quercus spp. 10 to 233] eastern cottonwood Populus deltoides 168] aspen-birch P. tremuloides-Betula papyrifera 35-200 [57,233] quaking aspen (west of the Great Plains) P. t. 7-120 [9,82,141] black cherry-sugar maple Prunus serotina-Acer saccharum > 1000 [233] mountain grasslands Pseudoroegneria spicata 3-40 (10**) [8,9] Rocky Mountain Douglas-fir* Pseudotsuga menziesii var. glauca 25-100 [9] coastal Douglas-fir* P. m. var. menziesii 40-240 [9,153,183] California mixed evergreen P. m. var. m.-Lithocarpus densiflorus-Arbutus m. California oakwoods Quercus spp. 9] oak-hickory Q.-Carya spp. 233] oak-juniper woodland (Southwest) Q.-Juniperus spp. 168] northeastern oak-pine Q.-Pinus spp. 10 to 233] coast live oak Q. agrifolia 9] white oak-black oak-northern red oak Q. alba-Q. velutina-Q. rubra 233] canyon live oak Q. chrysolepis blue oak-foothills pine Q. douglasii-P. sabiana 9] northern pin oak Q. ellipsoidalis 233] Oregon white oak Q. garryana 9] bear oak Q. ilicifolia 233] California black oak Q. kelloggii 5-30 [168] bur oak Q. macrocarpa chestnut oak Q. prinus 3-8 northern red oak Q. rubra 10 to post oak-blackjack oak Q. stellata-Q. marilandica black oak Q. velutina live oak Q. virginiana 10 to233] interior live oak Q. wislizenii 9] blackland prairie Schizachyrium scoparium-Nassella leucotricha Fayette prairie S. s.-Buchloe dactyloides little bluestem-grama prairie S. s.-Bouteloua spp. tule marshes Scirpus and/or Typha spp. 168] redwood Sequoia sempervirens 5-200 [9,62,209] western redcedar-western hemlock Thuja plicata-Tsuga heterophylla > 200 [9] eastern hemlock-yellow birch T. canadensis-Betula alleghaniensis > 200 [233] western hemlock-Sitka spruce T. h.-Picea sitchensis > 200 mountain hemlock* T. mertensiana 35 to > 200 [9] elm-ash-cottonwood Ulmus-Fraxinus-Populus spp. 57,233] *fire return interval varies widely; trends in variation are noted in the species summaryAbundant evidence of postfire establishment of Canada thistle [16,138,163,193] suggests that managers need to be aware of this possibility, especially if a known seed source is in the area, and take measures to prevent the establishment of Canada thistle after prescribed burning and wildfires. Seeding with aggressive, introduced grasses such as crested wheatgrass, intermediate wheatgrass, orchardgrass, and smooth brome following a prescribed burn in Utah pinyon-juniper communities prevented establishment of Canada thistle, whereas unseeded areas supported Canada thistle seedlings [77]. Similarly, in disturbed forest sites where Canada thistle becomes established, it may be shaded out over time as trees reestablish [56].
Research in this report suggests that response of Canada thistle to fire is variable and it depends on vegetation and site characteristics, as well as frequency, severity and season of burning. Prescribed burns may be effective at stimulating growth of native species and thereby discouraging the growth of invasives such as Canada thistle [182], and may be best if timed to emulate the natural fire regime of a site [44]. Hutchison [105] states that prescribed burning is a "preferred treatment" for the control of Canada thistle, and that late spring burns effectively discourage this species, whereas early spring burns can increase sprouting and reproduction. During the first 3 years of control efforts, he recommends that burns be conducted annually [105], though it is unclear what evidence these recommendations are based on. Season of burn is an important consideration for prescribed burning, as the timing of the burn will determine species composition and cover in the post-fire community [101,102]. Dormant season burning may be a preferred treatment method in some areas, because in many habitats it stimulates growth of native vegetation that subsequently competes with Canada thistle [252]. However, dormant season burning may not be as effective as late spring burning [105]. Controlled studies comparing the effects of these variables in different natural areas are currently lacking in the literature.
Equations for estimating fuel loading of forb communities including Canada thistle are available [27].
The USDA Forest Service's "Guide to Noxious Weed Prevention Practices" [224] provides several fire management considerations for weed prevention in general that apply to Canada thistle. To prevent invasion after wildfires and prescribed burns, re-establish vegetation on bare ground as soon as possible using either natural recovery or artificial techniques as appropriate to site objectives. When reseeding burn areas, use only certified weed-free seed. Monitor burn sites and associated disturbed areas after the fire and the following spring for emergence of Canada thistle, and treat to eradicate any emergent Canada thistle plants. Regulate human, pack animal, and livestock entry into burned areas at risk for weed invasion until desirable site vegetation has recovered sufficiently to resist weed invasion.
When planning a prescribed burn, preinventory the project area and evaluate cover and phenology of any Canada thistle present on or adjacent to the site, and avoid ignition and burning in areas at high risk for Canada thistle establishment or spread due to fire effects. Avoid creating soil conditions that promote weed germination and establishment. Discuss weed status and risks in burn rehabilitation plans. Wildfire managers might consider including weed prevention education and providing weed identification aids during fire training; avoiding known weed infestations when locating fire lines, monitoring camps, staging areas, helibases, etc., to be sure they are kept weed free; taking care that equipment is weed free; incorporating weed prevention into fire rehabilitation plans; and acquiring restoration funding. Additional guidelines and specific recommendations and requirements are available [224].Temperature: Canada thistle grows best between 32 and 90 degrees Fahrenheit (0-32 °C) [150,152]. Extended periods with temperatures over 90 degrees Fahrenheit (32 °C) reduce plant vigor and generally limit growth. High temperatures and shorter days keep Canada thistle from thriving in the southern U.S. Optimum day/night temperatures for growth are 77 and 59 degrees Fahrenheit (25 and 15 °C), respectively [85]. The northern limit of Canada thistle's growth corresponds to the 0 degrees Fahrenheit (-18 °C) mean January isotherm; flowering is also limited in the northern latitudes [150]. Canada thistle invasion of native rangelands appears to be a problem especially of highly productive, mesic habitats [179,203,252]. However, Canada thistle was able to infest subalpine fir/twinflower habitats in western Montana [68]. The temperature exposure of overwintering buds required to reduce survival of Canada thistle was 2 hours at 19 degrees Fahrenheit (-7 °C) and to reduce total dry weight was 2 hours at 23 degrees Fahrenheit (-5 °C) [192]. The ability of adventitious root buds to withstand freezing depends on their location in the soil profile [55,192]. In soil samples from a mid-boreal wetland subjected to increased temperatures, Canada thistle seedling emergence increased significantly (p<0.05) at higher temperatures [99,100].
Moisture: Canada thistle tolerates annual precipitation ranging from 12 to 40 inches (305-1015 mm) per year, and grows best with 16 to 30 inches (400-750 mm) of precipitation per year [83,150,152]. In range and pastureland, Canada thistle is often restricted to swales or other areas of deep, moist soils [128]. Canada thistle is concentrated in disturbed areas and along streams, rivers and other moist areas in Rocky Mountain National Park, although individual plants have been found on relatively dry, sagebrush-dominated sites [139]. A high water table limits root growth [185], but Canada thistle often occurs in wetlands where water levels fluctuate, and in degraded sedge meadows it may be found growing on tussocks elevated above the normal high water line. In a mid-boreal wetland subjected to drought, Canada thistle increased 5- to 13-fold over predrought levels [98,100]. Canada thistle survives well in dry places [185] and under extended periods of drought, but biomass and number of root buds decrease after several years [194]. Growth was increased by high relative humidity (90-100%) over low relative humidity (30-50%) [104].
Elevation and slope: Canada thistle occurs over a wide range of elevations from sea level [58] to elevations in excess of 8,000 feet (2,500 m) [49]. In the northern Rocky Mountains, it is found mainly by roadsides and other disturbed sites in the lower elevations and warmer, drier habitats, and escapes to undisturbed sites at upper elevations [140,235]. In Yellowstone National Park, Wyoming, Canada thistle occurs at elevations ranging from 5,970 to over 7,875 feet (1,820-2,400 m) [4]. In Rocky Mountain National Park, Colorado, Canada thistle coverage is greater at elevations around 8,375 feet (2,550 m) and decreases at elevations around 9,095 feet (2,770 m), but occurs up to at least 9,185 feet (2,800 m) [139]. Canada thistle grows best on shallow (9-30%) slopes [4,140].
Soils: The wide distribution of Canada thistle suggests that it is adaptable to many soil types [55,185]. It grows on all but waterlogged, poorly aerated, and peat soils, including clay, clay loam, silt loam, sandy loam, sandy clay, sand dunes, gravel, limestone, and chalk [161]. Rogers [185] suggests that Canada thistle grows best on limestone soils with abundant moisture. Some authors suggest that it is best adapted to clay soils [152]; others suggest that it prefers well-aerated soils [150]. Preliminary results in Rocky Mountain National Park indicate that soils supporting Canada thistle tended to have a surface (0-10 cm) texture higher in clay and silt than in sand [139]. Canada thistle was found growing on heavily saline soils in central Alberta, though it was absent from saline areas of Saskatchewan and Manitoba [24]. Hardpans, gravel, sand, or very alkaline soil horizons can limit root development of Canada thistle [185].
Competition and light: Canada thistle grows best in open sunny sites [150]. Canada thistle seedlings are much less competitive than established plants, and will survive only if competition is limited and the daytime light intensity remains above 20% of full sunlight [152]. In Rocky Mountain National Park, total canopy cover of vegetation within Canada thistle patches is less than outside the patches [139]. At Yellowstone National Park, Canada thistle was found in 6 out of 10 campgrounds, with occurrences most frequent under a canopy cover of less than 20%, although it was occasionally present under more closed canopy covers (up to 95%) suggesting that it is somewhat tolerant of shade. Twenty percent of the quadrats in which Canada thistle was present had no evidence of disturbance [4]. Because Canada thistle is relatively shade intolerant, it may be found growing along the edges of woods (both deciduous and coniferous), but is rarely found under forest canopy, in undisturbed prairies, good to excellent pastures, or woodland or sites that are shaded most of the day [83,105,161]. In the Delta Marsh in Manitoba, Canada thistle is present in communities dominated by common reed. It is capable of persisting on undisturbed plots, growing with stunted spindly stems and no flowers, but growth improves after disturbance [213].
Generally, Canada thistle establishes and develops best on open, moist, disturbed areas, including ditch banks, overgrazed pastures, meadows, tilled fields or open waste places, fence rows, roadsides, and campgrounds; and after logging, road building, fire and landslides in natural areas [4,45,106,115,122,138,158,163,188,193,216,220]. Roads, streams and ditches provide areas of disturbance and corridors for invasion. At Yellowstone National Park, Canada thistle was found in all levels of disturbance (along horse and foot trails, roadways, and campgrounds) and its abundance increased as disturbance cover increased [4,219]. Physically disturbed habitat in fragmented old growth in Indiana facilitated invasion by exotics including Canada thistle [26]. Canada thistle invasion was also enhanced by heavy grazing by bison [237], areas left barren during planting operations, and on earth mounds made by pocket gophers and badgers in North and South Dakota [93].
Canada thistle reproduces both sexually by seed and vegetatively by creeping roots. Generally, vegetative reproduction contributes to local spread and seeding to long distance dispersal. Introduction into new areas is mostly by wind- or water-borne seed, or by seed in contaminated crop seed, hay or machinery [55,105]. Canada thistle allocates most of its reproductive energy to vegetative propagation, and a patch can spread rapidly by vegetative means under favorable conditions. Total allocation of dry weight to sexual reproduction was only 7% for Canada thistle grown in pots [23]. However, the contribution of sexual reproduction to the survival and spread of Canada thistle may be underestimated and may be an important mechanism for initiating continued genetic diversity in a clonal population [89].
Sexual reproduction: Shoot elongation and flowering in Canada thistle are induced by 15-hour day length, therefore flowering and seed production will be limited or prevented in regions with shorter summer days [84]. A typical Canada thistle shoot may produce 32 to 69 flowerheads per shoot (1-5 per branch) on average, but can produce as many as 100 flowerheads in a season [150,152]. Canada thistle is "imperfectly dioecious" [55], with male and female flowers occurring on separate plants. Up to 26% of "male" plants are actually self-fertile hermaphrodites or subhermaphrodites that occasionally produce seed [108].
Seed production: Canada thistle is insect pollinated, primarily by honeybees [55,105,150]. Male and female plants must be located within a few hundred yards of each other for insect pollination and seed set to occur [84]. Seed set is highest when male and female plants are intermixed and decreases when female plants are more than 164 feet (50 m) from male plants [125]. Since Canada thistle can grow in large patches, it is not uncommon to find sterile heads of female flowers [125,152]. Canada thistle has a reputation for producing few viable seeds, but the literature gives a wide range of estimates for seed production with numbers ranging from 0 to 40,000 seeds per stem [38,89]. Reports of average seed-set per flowerhead range from 21-93 [89,152]. Kay [108] reports that females produce an average of 30 to 70 seeds/flowerhead and males average 2 to 10 seeds/head. The number of flowerheads per stem reported ranges from 0 to 100 [89]. In annual grasslands in northern California where biomass of Canada thistle was 13+ 8 g/m2, seed production was 1300 seeds/m2, seed rain was 80+ 50 seeds/m2, and germinable seeds in the top 2 cm of soil were 280+110/m2 [96]. Inefficient pollination and genetic variability may contribute to poor seed yields [89]. Seeds of Canada thistle are subject to predation by insects before dispersal, but information is more qualitative than quantitative [55,89]. Weather extremes (cool and moist or hot and dry) can interfere with pollination, so some years even female plants do not produce much seed [61].
Seed dispersal: Canada thistle seeds are released about 2-3 weeks after pollination [123]. They are equipped with a pappus, loosely attached to the seed tip, that enables wind dispersal, and have good aerodynamic efficiency [198]. Canada thistle seeds have been observed windborne on the prairie several hundred meters from the nearest source population [175]. Evidence from seed rain studies on Mount St. Helens, Washington suggests that Canada thistle seeds can travel several kilometers [249]. This dispersal mechanism accounts for the numerous examples of Canada thistle seedling establishment after disturbance in natural areas [45,106,109,216,220], especially after fire [138,163,188,193]. However, wind dispersal has not been considered a major factor in its spread, since the pappus readily breaks off, leaving the achenes within the seedheads [23]. In developed areas, seeds are more commonly spread by animals, in hay, contaminated crop seed, machinery, and irrigation water [161]. Observations in Rocky Mountain National Park indicate that trails, especially those used by horses, are major invasion pathways for Canada thistle [139]. Livestock consuming unprocessed hay before entering national forests will likely spread more Canada thistle seeds than those consuming feed pellets, since pellet manufacturing destroys 99% of viable Canadian thistle seed when it includes grinding and screening [35].
Viability and germination: Canada thistle seeds mature quickly and most are capable of germinating 8 to 11 days after the flowers open, even if the plants are cut when flowering. Moore [150] summarized research indicating that almost all Canada thistle seed can germinate upon dispersal, although germination is extremely variable (0-95%). Viability of seeds during the 1st season after dispersal may be as high as 90% [84]. Most seeds germinate in the spring after the year in which they are produced [97,188], with some seeds producing basal leaves before winter and emerging to flower the next spring [105]. However, Heimann and Cussans [89] indicate that seedlings are not always able to survive the winter. Germination may be affected by ecotype, temperature, day length, depth of seed burial, substrate stratification, and seed freshness [161]. Seeds from "male" plants are smaller and percent germination is lower [108]. Temperature requirements for germination were summarized by Moore [150]; the effects of light, pH, and salinity are summarized by Donald [55]. Canada thistle seeds germinate best in warm temperatures (68 to 104 degrees Fahrenheit (20-40 °C)), with alternating light and dark periods [22,188,245]. Germination in Canada thistle was best after 0.5 to 16 days at 88 to 108 degrees Fahrenheit (31-42 °C) [212]. At lower temperatures germination is aided by high light intensity [89,97]. Germination at higher temperatures can help ensure that maximum germination takes place during warmer periods of the year [89]. Canada thistle seeds are somewhat tolerant of heat, and some were still viable after 10 minutes at 216 degrees Fahrenheit (102 °C) and 2 minutes at 504 degrees Fahrenheit (262 °C), although viability was decreased at these temperatures compared to unheated controls [212]. Canada thistle seeds germinate over a wide range of soil moisture [245]. Heimann and Cussans [89] provide a summary indicating that Canada thistle seed can germinate on the soil surface, but that germination is best when seeds are buried 0.2 to 0.6 inch (0.5-1.5 cm) deep. Emergence as deep as 6 cm in some soil types has been reported [245]. Most germination studies have been done under artificial conditions, and factors influencing germination in the field are far more complex [89].
Seed banking: The soil seed bank does not usually contain large numbers of Canada thistle seeds [36,184], although there is evidence of seed banking in a coastal British Columbia coniferous forest soil [110], in mature forest sites in central Idaho [117], and in the Delta Marsh in Manitoba [229]. Length of survival is related to depth of burial, with seeds surviving up to 22 years when they are buried more than 8 inches (20 cm) deep [78]. Under more natural conditions of shallower burial and periodic soil disturbance, Canada thistle seeds are more short lived (<5 years), with most seed being lost from the soil seed bank by germination during the 1st year [55]. Seeds that have been in water for several months can still be viable [84]. Donald [55] summarizes the research on seed banking in Canada thistle and the effects of seed immersion in water.
Seedling establishment: Canada thistle seedlings usually start growing slowly and are sensitive to competition and shading [55,89,128]. Seedlings grow poorly in very moist, poorly aerated soils and do not tolerate drought stress [245]. Before seedlings become perennial, they are also highly susceptible to tillage [152].
Asexual reproduction: Vegetative spread of Canada thistle can occur from horizontal extension of the root system, from root fragments, or from subterranean stem tissue [131]. Spread can be rapid when there is little competition, with 13 to 20 feet (4-6 m) of horizontal root growth possible in one season [97,185]. Canada thistle can develop new aerial shoots at any location along the root length, from the original vertical root, or from buds on lateral roots. Within a few weeks of germination, a Canada thistle seedling with at least 4 true leaves can begin producing root buds that can eventually produce new shoots [84]. Buds on lateral roots may form new adventitious shoots as frequently as 0.3 to 1-inch (0.8 to 2.4 cm) intervals [103], although the number of root buds is likely to vary from place to place and year to year [157]. A single Canada thistle plant can potentially produce 26 adventitious shoots, 154 adventitious root buds, and 364 feet (111 m) of roots after 18 weeks of growth [152,157]. It is possible that a colony of male plants would maintain itself regardless of whether it produced fruits [240].
Root buds are inhibited by the presence of the main shoot, primarily due to a competition for water [104], and new root bud growth is highest during late fall and winter months following death of aerial shoots [137]. When the main shoot is removed (e.g. as by mowing) the root buds are released, and new shoots emerge rapidly, especially when humidity is high [104,157]. Wilson [245] found that some 19-day old plants were capable of regenerating top-growth after clipping, and that 40-day old plants could produce 2 or 3 shoots after clipping. Root fragments as short as 0.2 inch (6 mm) and more than 6 weeks but less than 2 years old can regenerate entire plants, regardless of whether they have identifiable root buds at the time [157]. Nadeau and Vanden Born [157] observed that an 18-week-old plant had the potential of producing 930 shoots if its root system was cut into 10-cm-long pieces.
Vegetative spread of Canada thistle may also occur from subterranean stem tissue that can produce shoot buds and adventitious roots at each node. Partially buried stem sections from the postbloom stage survived and produced adventitious roots that over wintered and produced new infestations the following spring [131]. Similarly, Canada thistle can survive disturbance to be part of the early successional community in natural areas by resprouting from buried root and stem fragments [2,45,188,216].
Cirsium arvense (cardu cundidor) ye una planta de la familia de les asteracees.
Erecta, viviega, con tarmos bien ramosos, foliosos, non alaos d'hasta 1,5 m, y con estolones rastreres llongures de biltos foliosos. Fueyes llanceolaes a oblongues, enteres o estremaes con lóbulos trinagulares espinosos, glabres o con pelos como de telaraña. 1-5 capítulos moráu claro, de 1,5-3 cm de llargu, de cabillo curtiu, col ápiz de les cañes. Bráctees involucrales violeta escuru, erectas, les esternes, romes. Flores pentalobulaes, con llargu tubu corolino. Especie bien variable. Floria nel branu.[1]
Campos de llabranza, camperes, tierres baldías, escamplaes nel monte.
Toa Europa. Introducíu n'Islandia.
Tien propiedaes astrinxentes.
Utilízase tamién la planta entera externamente en forma de baños contra les hemorroides.[2]
Cirsium arvense describióse por (Carlos Linneo) Scop. y espublizóse en Flora Carniolica, Editio Secunda 2: 126–127. 1772.[3]
Númberu de cromosomes de Cirsium arvense (Fam. Compositae) y táxones infraespecíficos: 2n=34[4]
Cirsium: nome xenéricu que deriva de la pallabra llatina cirsĭŏn, -ĭi —del griegu χιρσός, -ον, varices— vocablu qu'usa Pliniu'l Vieyu (Naturalis Historia, 27, 61) pa identificar un cardu que s'utiliza pal tratamientu d'esti tipu de dolencia. Nos tiempos modernos, el botánicu francés Tournefort (1656 - 708) derivó'l nome Cirsium.
arvense: epítetu llatín deriváu de arvus, -a, -um que significa "de los campos".[5]
.
Esta páxina forma parte del wikiproyeutu Botánica, un esfuerciu collaborativu col fin d'ameyorar y organizar tolos conteníos rellacionaos con esti tema. Visita la páxina d'alderique del proyeutu pa collaborar y facer entrugues o suxerencies. Cirsium arvense (cardu cundidor) ye una planta de la familia de les asteracees.
Ar dreinaskol (pe dimezelled, pe soudarded) zo ur blantenn bevek eus kerentiad an Asteraceae.
0,60 - 1,50 m.
Glaz-ruz. Douget eo bleunioù par ha parez gant plant disheñvel.
Brudet e oa evit pareañ ouzh ar gwazrudez.
Ar dreinaskol (pe dimezelled, pe soudarded) zo ur blantenn bevek eus kerentiad an Asteraceae.
La calcida[1] o calciga (Cirsium arvense) és una planta considerada una mala herba.
Les calcides pertanyen a la família botànica abans anomenada "Compostes" i actualment Asteraceae.
Es troben dintre del gènere "Cirsium" del qual n'hi ha unes 150 espècies en tot el món.
Cirsium arvense té la forma d'un card d'uns 30 a 100 cm d'alçada. Les arrels són reptants i profundes i formen tiges erectes sense pèls, les fulles no tenen pecíol i són pinnatífides o pinnatipartides plenes de punxes petites. Capítols agrupats en corimbe. Floreix de juliol a setembre. Els fruits són en forma d'aqueni de 3 a 4 mil·límetres. Fa uns "papus" o sigui plomalls per a dispersar pel vent els aquenis.
Es tracta d'una mala herba vivaç, és a dir que viu uns quants anys. Germina a la primavera i creix fins a la tardor. Amb la gran facilitat de dispersió que li donen les seves llavors transportades pel vent, molt aviat envaeix el territori encara que només sigui a rodals. Com està recoberta de punxes és molt difícil d'arrencar a mà i quan això s'aconsegueix no queda eliminada perquè rebrota des de l'arrel que és molt profunda. Amb herbicides no s'elimina tampoc fàcilment i cal un producte sistèmic i a més aplicat en el moment en el qual la calcida és més sensible que és precisament quan floreix.
Es troba a tota Europa inclosa les zones més fredes com Islàndia i Escandinàvia.
Als Països Catalans es troba per tot el territori, a excepció de l'extrem sud del País Valencià, des del nivell del mar fins als 1.600 metres aproximadament, en camps de conreu nitròfils sobre sòls profunds i no gaire secs.
Planhigyn blodeuol o deulu llygad y dydd a blodyn haul ydy Ysgallen y maes sy'n enw benywaidd. Mae'n perthyn i'r teulu Asteraceae. Yr enw gwyddonol (Lladin) yw Cirsium arvense a'r enw Saesneg yw Creeping thistle.[1] Ceir enwau Cymraeg eraill ar y planhigyn hwn gan gynnwys Ysgallen Gyffredin, Llawegor, Ysgallen Gwraidd Rhedegog, Ysgallen Gyffredin yr Âr, Ysgallen Llusg-wraidd, Ysgallen y Maes, Ysgallen yr ŷd.
Daw'r gair "Asteraceae", sef yr enw ar y teulu hwn, o'r gair 'Aster', y genws mwyaf lluosog o'r teulu - ac sy'n tarddu o'r gair Groeg ἀστήρ, sef 'seren'.
Planhigyn blodeuol o deulu llygad y dydd a blodyn haul ydy Ysgallen y maes sy'n enw benywaidd. Mae'n perthyn i'r teulu Asteraceae. Yr enw gwyddonol (Lladin) yw Cirsium arvense a'r enw Saesneg yw Creeping thistle. Ceir enwau Cymraeg eraill ar y planhigyn hwn gan gynnwys Ysgallen Gyffredin, Llawegor, Ysgallen Gwraidd Rhedegog, Ysgallen Gyffredin yr Âr, Ysgallen Llusg-wraidd, Ysgallen y Maes, Ysgallen yr ŷd.
Daw'r gair "Asteraceae", sef yr enw ar y teulu hwn, o'r gair 'Aster', y genws mwyaf lluosog o'r teulu - ac sy'n tarddu o'r gair Groeg ἀστήρ, sef 'seren'.
Pcháč rolní (Cirsium arvense) je vytrvalá, dvoudomá, ostnitá rostlina kvetoucí v létě růžově fialovými květy sestavenými do mnoha úborů a je v mnoha zemích považována za jeden z nejnebezpečnějších a velmi obtížně likvidovatelných plevelů. V české krajině není původní druh, ale archeofyt se silně invazním chováním.[1][2]
Centrum původu pcháče rolního není zcela jasné, pravděpodobně pochází z jihovýchodní Evropy z oblastí okolo Středozemního moře, odkud se v 16. století kontaminaci osiva rozšířil po celé Evropě, západní Asii a severní Africe. V 17. století se dostal do Severní Ameriky, kde nyní roste hlavně mezi 37° a 59° severní zeměpisné šířky, o málo později do mírného pásma Jižní Ameriky, Austrálie i na Nový Zéland.
V ČR je rostlinou hojnou po celém území, roste hlavně v termofytiku a mezofytiku, méně častěji v oreofytiku. Vyskytuje se od planárního po montánní stupeň, vzácně i výše, nejvýše byl zaznamenán v Krkonoších na Luční hoře a v Hrubém Jeseníku na Pradědu ve výškách okolo 1500 m n. m.[1][2][3]
Pcháč rolní patří mezi významné plevele, je řazen mezi deset hlavních plevelů světa, má vysoké nároky na odběr živin i vody, zastiňuje kulturní rostliny a jeho kořeny vylučují alelopatické látky, které působí inhibičně na pěstované plodiny a jiné plevele. Roste na čerstvě vlhkých až sušších půdách různých struktur, včetně kyselých s hodnotami pH mezi 3 a 4, stejně jako na mírně zasolených. Vyskytuje se na polích, kde roste téměř ve všech zemědělských kulturách, hlavně v obilovinách, okopaninách, v zahradách, na vlhčích pastvinách, loukách i opuštěné zemědělské půdě, na pasekách, kamenitých stráních, podél cest a na různých náspech. Preferuje půdy vápnité, hluboké a hlinité, dokáže však růst i na místech velmi suchých, neboť jeho kořeny sahají až do hloubky dvou i více metrů a obvykle tam dokáží získat vodu.
Až do podorniční vrstvy sahá rozvětvený, několikapatrový sytém vodorovných i svislých kořenů s velkým počtem adventivních pupenů, nejhojnější bývá do hloubky asi 35 cm. Postranní kořeny často až hlízovitě tloustnou a jsou zásobárnou živin, jejichž množství v nich silně klesá v době květů a plodů a obnovuje se zase na podzim. Na těchto postranních kořenech a horní části hlavního kořene průběžně vzniká, i v zimě pod zmrzlou půdou, mnoho pupenů a z nich rostlina na jaře vytváří celé kolonie.
Mladé výhonky z jara vyrážejí na povrch, vytvoří listovou růžici a květonosnou lodyhu a na podzim odumírají až do hloubky, kde přirůstají ke kořenu. Nepoškozené kořeny během několika let vymírají a přestávají vytvářet nové výhonky a rostlina na tomto místě hyne. Naopak orba rostlinu podporuje, neboť kořeny se spícími pupeny jsou roznášeny po poli a vznikají tak rostliny nové.
Semeno klíčící na podzim vytvoří malou listovou růžici, která sice přes zimu odumírá, ale předem vytvoří kořen a na jaře z něj vyroste nová růžice a květonosná lodyha. Semeno vyklíčené až na jaře většinou vytvoří jen růžici listů, která obvykle uschne. Většina mladých růžic vyrašených na jaře není ze semen, ale je tvořena novými výhonky z kořenů. Jedná rostlina dokáže během dvou vegetačních sezón kolonizovat plochu o průměru dvou metrů. Ze semen vyrostlé exempláře jsou na obdělávaných půdách poměrně vzácné, neboť semenáče bývají zničeny při jarním nebo podzimním zpracováváním půdy. Ploidie druhu je 2n = 34.[1][2][4][5][6][7]
Vytrvalá, dvoudomá, ostnatá bylina s přímou lodyhou 50 až 120 cm vysokou, rostoucí z přibližně 2 m dlouhého a široce do stran rozprostřeného kořene. Lodyha je tuhá, v horní části silně rozvětvená a někdy je dolní půli přerušovaně nebo souvisle ostnitě křídlatá. Je po celé délce olistěná, lysá nebo pavučinatá a zelená či hnědofialově naběhlá. Listy v přízemní růžici jsou zúžené v řapík, vejčitě obkopinaté, celistvé nebo peřenolaločné a záhy zasychají. Střídavé lodyžní listy bez palistů přisedající zúženou srdčitou bázi jsou velmi variabilní, mohou být vejčitě kopinaté až podlouhlé, po obvodě bývají celokrajné nebo mělce vykrajované či peřenolaločné až peřenosečné, někdy mívají okraj zkadeřený a slabě až silně ostnitý a na spodu jsou vlnaté nebo lysé.
Na konci lodyhy a jejich větví vyrůstají jednotlivě úbory, celkově jich bývá 10 až 30 a vytvářejí bohatou chocholičnatou latu. Samičí rostlina má úbory menší, bývají široké 14 až 20 mm a obsahují 100 až 140 květů, u samčí rostliny jsou široké až 30 mm a mívají 90 až 130 květů; obvykle bývá větší počet rostlin samičích. Květy mají redukovaný kalich a jsou zpravidla funkčně samčí nebo samičí, samčí ale občas vytvoří několik životaschopných nažek, které jsou drobnější a hůře klíčí. Růžově fialové trubkovité koruny květů jsou rozeklané až k bázi v čárkovité cípy. Samičí květy s korunou dlouhou asi 15 mm silně voní po medu nebo vanilce a mají tyčinky se zakrnělými prašníky o málo kratší než koruna a pestíky s rozevřenými rameny blizen. Samčí květy s korunou dlouhou asi 20 mm voní po medu pouze slabě, tyčinky s vyvinutými prašníky s trikolporátním pylem jsou o málo delší než koruna a pestík má v době kvetení ramena blizen k sobě přitlačená. Zákrov úborů je podlouhle vejčitý až válcovitý, nafialovělý, pavučinatý a lepkavý, asi 1,5 cm dlouhý a samičí se za plodů prodlužuje na délku 2 cm. Zákrovní listeny jsou nahoře fialově naběhlé, vnější jsou zakončené vně zakřiveným měkkým, bělavým ostnem, střední a vnitřní jsou širší a směrem do středu i delší a mají vně zahnutou špičku nebo osten. Rostliny kvetou v červnu až září, produkují nektar a jsou opylovány hmyzem, hlavně včelami.
Plod je béžová, zelenavá, světle žlutá až světle hnědá či tmavě hnědá nažka dlouhá 3 až 4 mm a široká 1 mm. Je hladká, zploštělá, zahnutá nebo přímá a zakončená valem s hrbolkem uprostřed. Chmýr má pérovitě větvený (rozlišovací znak od bodláků, které mají chmýr nevětvený), zpočátku špinavě bílý a později nažloutlý, u nažek ze samičích rostlin bývá dlouhý 2 až 2,5 cm a ze samčích jen 1 až 1,5 cm.[1][2][4][5][6][7][8][9]
Rostlina se může rozmnožovat vegetativně nebo generativně, vegetativní rozmnožování silně převládá na obdělávané půdě. Přerušování kořenů a jejich výběžků způsobuje řízkování rostliny a vyvolává aktivaci dosud spících pupenů, ze kterých vyrůstají noví jedinci s vysokou konkurenční schopností. Jarní čerstvé lodyhy se rychle prosazují i v hustě setých plodinách, jako jsou obiloviny, luštěniny i ozimá řepka, nejvíce však poškozují širokořádkové plodiny s malou schopností jim konkurovat, jako brambory, řepa, zelenina, kukuřice.
Při generativním rozmnožování je důležité množství vyprodukovaných semen, jejich klíčivost, dormance, délka životnosti v půdě a způsob šíření. V samičím úboru pcháče rolního se vytváří pouze okolo 80 nažek a z nich je mnoho parazitováno nebo nedozraje, počet živých nažek v úborech tak obecně bývá jen 10 až 15 %. Nažky se šíří především areochorně větrem až na vzdálenost 3 km. Šíří se i vodou, ve které vydrží po několik dnů bez újmy na klíčivosti. Dochází také k zoochornímu šíření. Chmýří se lepí se na srst zvířat i oblečení a boty lidí, semena roznášejí též ptáci živící se jimi nebo hlodavci ukládající si je do zimní zásoby, stejně jako mravenci zanášející je pro obsah tuku a bílkovin do mravenišť. Semena prošlá zažívacím traktem dobytka také neztrácejí klíčivost.
V půdě si zachovávají klíčivost běžně 6 a ojediněle až 20 roků, část se jich dostává i mezi semena sklizených plodin. Dobře klíči již na podzim ihned po dozrání, hlavně při teplotách přes 20 °C a z povrchu nebo hloubky do 2 cm, u nižších teplot klíčí nepravidelně, pomalu a z hloubky nad 5 cm nevyklíčí vůbec. Pro rozšíření druhu na zcela nové místo je důležité, aby se tam dostaly samčí i samičí rostliny.[4][5][6][7][10][7]
Pcháč rolní je velmi rozšířený obtížný plevel rostoucí v jednoletých i víceletých obilovinách i okopaninách, na vinicích, chmelnicích i zelinářských zahradách. Obzvláště silně se rozrůstá v jarních obilovinách a okopaninách sázených do nesprávně ošetřované půdy a při nedodržování pravidel o střídání plodin a nepoužívání herbicidů.
Mělké zpracování půdy poškozuje pouze svrchní část kořenového systému, což vyvolává velmi silnou regeneraci vedoucí k rychlému přemnožení. Snaha o jeho mechanickou likvidaci nebývá úspěšná ani při hluboké orbě, jeho mohutné, do hloubky sahající kořeny nelze mechanicky zcela zničit, ze spících pupenů na úlomcích roztrhaných kořenů vždy vyraší noví jedinci. Slabina pcháče rolního však spočívá v tom, že sice velmi silně odnožuje pokud jsou poškozovány kořeny, ale jakmile toto ustane a půda ulehne, v několika létech rostlina uhyne.
K jeho chemické likvidaci se obvykle používá, s ohledem na okolní kultury, systémově působící růstový herbicid. Aplikuje se ve fázi, kdy má listová růžice dva až tři listy, herbicid je listy jímán a následně proniká do kořenů které ničí. Chybné použití herbicidu v ranější růstové fází nebo ve slabší koncentraci se v mnoha případech projeví následným hromadným rašením nových výhonů.[1][2][4][5][6][7]
Listová růžice
Mladá rostlina
Úbory před květem
Úbor s kvetoucími květy
Úbory se zrajícími nažkami
Nažka s chmýrem
Obrázky, zvuky či videa k tématu pcháč rolní ve Wikimedia Commons
Pcháč rolní (Cirsium arvense) je vytrvalá, dvoudomá, ostnitá rostlina kvetoucí v létě růžově fialovými květy sestavenými do mnoha úborů a je v mnoha zemích považována za jeden z nejnebezpečnějších a velmi obtížně likvidovatelných plevelů. V české krajině není původní druh, ale archeofyt se silně invazním chováním.
Agertidsel (Cirsium arvense), ofte skrevet ager-tidsel, er en 50-100 cm høj urt, der vokser på agerjord og strandvolde. Agertidsel er en af de mest frygtede ukrudtsarter i jordbruget.
Agertidsel er en flerårig urt, som tilhører Kurvblomst-familien. Væksten er opret med stive, furede stængler. Bladene er spredtstillede, ægformede og bølgede, men også fligede med tornet-tandet rand. Oversiden er mørkegrøn, mens undersiden er gråhåret.
Blomstringen sker i august-september, og de små rødlilla enkeltblomster sidder i oprette kurve, som igen er samlet i endestillede halvskærme. arten er særbo, så det er kun de hunlige planter, der danner frø. Hvert frø har en fjerformet fnok.
Rodnettet består af vandrette jordstængler, som kan ligge i 1–2 meters dybde og gerne i komprimerede jordlag. Derfra skyder lodrette skud op til overfladen. Desuden bærer jordstænglerne almindelige rødder. Denne voksemåde gør, at agertidsel kan danne tætte bestande, som dækker jorden fuldstændigt.
Højde x bredde og årlig tilvækst: 1 x 50 m (100 x 500 cm/år). Målene kan bruges til beregning af planteafstande i fx haver.
Agertidsel vokser på græsningsarealer, marker og ruderater, hvor den danner rene bestande. Den er en del af den højstaudeflora, som formidler successionen fra flerårigt ukrudt til krat. Det kan f.eks. ses, at arten nedkæmper bestande af alm. kvik.
Blomsterne rummer både nektar og pollen og søges gerne af honningbier og humlebier.
Agertidsel er en af de mest frygtede ukrudtsarter i jordbruget. De tornede blade og de dybtliggende jordstængler gør det besværligt at bekæmpe den med håndkraft, og det er ét af de gode argumenter for indførelsen af muldfjæl på ploven, at det gør det muligt at holde denne art nede.
Agertidsel (Cirsium arvense), ofte skrevet ager-tidsel, er en 50-100 cm høj urt, der vokser på agerjord og strandvolde. Agertidsel er en af de mest frygtede ukrudtsarter i jordbruget.
Die Acker-Kratzdistel (Cirsium arvense) oder Ackerdistel ist eine Pflanzenart aus der Gattung der Kratzdisteln (Cirsium) innerhalb Familie der Korbblütler (Asteraceae). Sie fällt vor allem wegen ihrer bedornten Blätter und ihrer violett gefärbten Blüten auf. Man findet sie an Weg- und Feldrändern, deshalb wird sie auch oft als „Ackerunkraut“ bezeichnet.
Die Acker-Kratzdistel ist extrem variabel in Unterschieden in der Wuchshöhe, der Ausgestaltung der Laubblätter und der Größe der Blütenkörbchen. Sie wurde deshalb von manchen Autoren in zahlreiche Unterarten und Varietäten untergliedert, die jedoch schwer trennbar sind.
Die Acker-Kratzdistel ist eine ausdauernde krautige Pflanze, die Wuchshöhen von 30 bis 150 Zentimetern erreicht. Sie bildet waagrecht verlängerte, kriechende Rhizome aus. Der Stängel ist reich beblättert, meistens rispig verzweigt und nicht geflügelt.
Die wechselständig angeordneten Laubblätter sind buchtig gezähnt und weisen eine dornige Bewimperung auf. Die weichen bis starren Dornen sind etwa fünf Millimeter lang und spitz. Im oberen Stängelbereich sind die Laubblätter jedoch nicht stachelig.
Die Blütezeit reicht von Juli bis Oktober. Die Acker-Kratzdistel ist gynodiözisch. Die Blütenkörbchen weisen einen Durchmesser von etwa zwei Zentimetern auf und enthalten etwa 100 meist zwittrige, vormännliche Blüten. Daneben gibt es aber auch rein weibliche Pflanzenexemplare mit kleineren Körbchen und Blüten mit nur zwei bis drei Millimeter langen Kronzipfeln. Der Blütenstand enthält, wie bei allen Arten der Tribus Cardueae nur Röhrenblüten. Ihr farbiger Blütenkronensaum ist bis zum Grund fünfspaltig. Die Blüte ist rötlich bis lilafarben.
Die Achäne besitzt einen federigen Pappus aus weißen Pappusborsten.
Die Chromosomenzahl beträgt 2n = 34.[1]
Die Acker-Kratzdistel ist ein Wurzelknospen-Geophyt und ein Tiefwurzler, der bis 2,8 Meter tiefe Wurzeln treibt. Die vegetative Vermehrung der Acker-Kratzdistel erfolgt durch Wurzelsprosse, die aus den tief im Boden liegenden, annähernd waagerecht verlaufenden Ausläuferwurzeln hervorgehen. Es liegt demnach ein Wurzelpionier vor, der auf Äcker und Weiden ein gefürchtetes „Unkraut“ darstellt. Sogar aus kleinen abgehackten Wurzelstückchen können neue Pflanzenexemplare austreiben.
Die Blüten duften nach Honig. Die Griffeläste sind auf der Außenseite dicht mit Fegehaaren besetzt. Diese herauswachsende Griffelbürste schiebt den Pollen aus der sich nach innen entleerenden Staubblattröhre hinaus. Der Nektar steigt in der bis über 10 Millimeter langen Kronröhre bis zum Ausgang. Dadurch ist er Insekten aller Art zugänglich, insbesondere für Tagfalter ist die Acker-Kratzdiste eine wichtige Nektarquelle. Bei schlechtem Wetter findet in den Zwitterblüten spontane Selbstbestäubung statt. In den Blüten ist Cynarin (1,3-O-kaffeoylchinasäure) enthalten.
Die Achänen besitzen einen hygroskopischem Haarkelch (Pappus): Es liegt also ein Schirmchenflieger vor. Dessen Sinkgeschwindigkeit beträgt nur 26 cm/Sekunde, daher werden bei Aufwind Flugweiten über 10 km möglich. Die Früchte sind im August bis Oktober reif, jeweils bereits etwa vier Wochen nach Blühbeginn. Die Acker-Kratzdistel ist bezüglich ihrer Standortwahl sehr anspruchsvoll, nur an geeigneten Standorten keimen ihre Samen aus.
Am Stängel der Acker-Kratzdistel findet man nicht selten bis über 2 Zentimeter dicke Gallen, hervorgerufen durch die Larven der Distelbohrfliege (Urophora cardui).
Mehrere Rüsselkäferarten entwickeln sich an der Acker-Kratzdistel, häufig etwa der Distelkurzrüssler oder der Kratzdistelrüssler.
Der Rostpilz Puccinia punctiformis befällt die Acker-Kratzdistel[2] und wird daher auch in Nordamerika und Neuseeland zur Biologischen Schädlingsbekämpfung der Acker-Kratzdistel erfolgreich eingesetzt.[3]
Die Acker-Kratzdistel kommt vor allem an Wegrändern und Ruderalstellen in ganz Mitteleuropa vor. Selten wächst sie in Höhenlagen oberhalb 2000 Metern. In den Allgäuer Alpen steigt sie an der Alphütte der neuen Piesenalpe bei Rohrmoos in Bayern bis in eine Höhenlage von 1480 Meter auf.[4]
Die Acker-Kratzdistel ist in Mitteleuropa ein sogenannter Apophyt, da die ursprünglich auf trockenen Waldgrenzstandorten heimische Art auf anthropogene Standorte wechselte, als in Mitteleuropa vor etwa 7000 Jahren Wälder durch Menschen gerodet wurden, um Platz für Äcker zu schaffen. Diese Standorte waren offener als die meisten natürlichen und sie wurden regelmäßig gestört und boten damit der Acker-Kratzdistel optimale Lebensbedingungen. Sie gedeiht am besten auf trockenen Standorten, gelegentlich findet man sie aber auch an feuchteren, halbschattigen Standorten, sowie häufig in Gebüschen und Hecken. Sie gedeiht in Mitteleuropa in Pflanzengesellschaften der Klassen Artemisietea, Agropyretea, Epilobietea und Secalietea.[1]
Die Erstveröffentlichung erfolgte 1753 unter dem Basionym Serratula arvensis durch Carl von Linné in Species Plantarum, Band 2, Impensis Laurentii Salvii, Holmiae, Seite 820.[5] Das Artepitheton arvensis/arvense bedeutet „auf Äckern wachsend“. Die Neukombination zu Cirsium arvense (L.) Scop. wurde 1772 durch Giovanni Antonio Scopoli in Flora Carniolica ..., 2. Auflage, Band 2, Seite 126 veröffentlicht. Es gibt viel Synonyme.[6]
Für die Acker-Kratzdistel bestehen bzw. bestanden auch die weiteren deutschsprachigen Trivialnamen: Dästel (Siebenbürgen), Tästel (Siebenbürgen), Danoisa (Memmingen), Danoise (Memmingen), Diessel (Ostfriesland), Distel (Österreich), Haberdistel, Landschnecht (St. Gallen), Klein Margendistel (Schlesien), Mausdistel (Göttingen), Ruchdistel (St. Gallen am Oberrhein), Saudistel, Stechdistel (St. Gallen), Stikel (Ostfriesland), Tissel (Helgoland), Tässel (Siebenbürgen) und Warzendistel.[7]
Blütenstand im Detail und Blütenbesucher
Pieris napi als Blütenbesucher
Acker-Kratzdistel vor dem Aufblühen
Pappus
Fruchtstand und Pappus
Die Acker-Kratzdistel (Cirsium arvense) oder Ackerdistel ist eine Pflanzenart aus der Gattung der Kratzdisteln (Cirsium) innerhalb Familie der Korbblütler (Asteraceae). Sie fällt vor allem wegen ihrer bedornten Blätter und ihrer violett gefärbten Blüten auf. Man findet sie an Weg- und Feldrändern, deshalb wird sie auch oft als „Ackerunkraut“ bezeichnet.
Aɣeddu n weɣyul (Isem usnan: Cirsium arvense) d talmest n yemɣi seg twacult n tetrawt. Giovanni Antonio Scopoli 
d amdan amezwaru i yuran fell-as deg useggas n 1772.
Aɣeddu n weɣyul (Isem usnan: Cirsium arvense) d talmest n yemɣi seg twacult n tetrawt. Giovanni Antonio Scopoli d amdan amezwaru i yuran fell-as deg useggas n 1772.
Cirsium arvense is a species o Cirsium, native throughoot Europe an northren Asie, an widely introduced elsewhaur. The staundard Inglis name in its native aurie is Creeping Thistle.[1][2][3]
Cirsium arvense is a species o Cirsium, native throughoot Europe an northren Asie, an widely introduced elsewhaur. The staundard Inglis name in its native aurie is Creeping Thistle.
Jeże (Cirsium arvense (L.) Scop.) - wielelatnô roscëna z rodzëznë astrowatëch. Òne roscą m. jin. na Kaszëbach. Lëstë ti roscënë kòlą.
Jeże (Cirsium arvense (L.) Scop.) - wielelatnô roscëna z rodzëznë astrowatëch. Òne roscą m. jin. na Kaszëbach. Lëstë ti roscënë kòlą.
Pužući čičak (latinski: Cirsium arvense) – poznat i kao čičak palamida – je cvjetnica roda Cirsium, koja prirodno raste širom Evrope i Sjeverne Azije, a drugdje je široko unesena vrsta.[1][2][3][4][5][6]
Cirsium arvense je višegodišnja zeljasta biljka koja naraste i do 150 cm, stvarajući klonske kolonije od zadebljalog korijena, koji šalje brojne izbojke tokom vegetacije.[7]
Podzemna mreža sastoji se od četiri vrste struktura:
Stabljike narastu do oko 30–150 cm, vitke su i zelene, slobodno razgranate,[10] glatke i loptaste, bez trihoma i plavozelene boje, najčešće bez trnastih krila. Lišće je na vretenu naizmjenično sa kitnjastom bazom i ljuskama ili skoro povijena. Listovi su vrlo trnoviti i režnjeviti, dugi do 15–20 cm, te široki oko 2–3 cm (manji na donjem dijelu cvijetne stabljike).
Cvijeće ima prečnik oko 10–22 mm, ružičasto-ljubičasti, sa svim floretima sličnog oblika (bez podjele na disk i cvjetne zrake). Cvjetovi su veċinom episkopni, uz neke biljke koje imaju hermafroditne cvjetove.[10]Sjemenke su duge 4–5 mm, sa perastim papusom koji pomaže za njihovo raznošenje putem vjetra.[11][12] Na svakoj grani nose 1–5 cvjenih glavica, a u povoljnim uslovima mogu proizvesti i do 100 glavica po izdanku.[7] Svaka glava sadrži prosječno 100 cvjetova. Procjenjuje se da prosječna proizvodnja sjemena po biljci iznosi oko 1530 sjemenki. Pretežno ih oprašuju insekti.[7]
Kao predstavnik "eudikotiledonske" monofiletske grupe, Cirsium je "prava dikotiledona". Brojne brazde i porfe polenovih zrna služe za klasificiranje cvjetnica u eudikotiledone, koje imaju kolpuse (trikolpate).[13][14] Cirvius arvense je biljka sa fiksacijom ugljika C3. Takve biljke potiču iz vremena mezozoika i paleozoika. Posebno napreduju u područjima u kojima je umjeren intenzitet sunčeve svjetlosti, umjerena temperatura, a podzemne vode ima u izobilju. C3 biljke izgube i do 97% vode koju uzimaju kroz korjenove, pomoću transpiracije.[15]
Ovo je ruderalna vrsta.[16]
Varijacije u obilježjima lista (tekstura, vestitura, segmentacija, trnovi) osnova je za utvrđivanje varijeteta puzajućeg čička.[7] Prema Flori Sjeverozapadne Evrope[3] postoje dva varijeteta:
Opisana su i četiri kanadska varijeteta:
Sjemenke su važna hrana za evropske češljugare i konopljarke, a u manjoj mjeri i za druge ptice.[17] Lišće pužućeg čička koristi se kao hrana za više od 20 vrsta Lepidoptera, uključujući i leptira Vanessa cardui, neke vrste moljaca i nekoliko vrsta biljnih vašiju.[18][19][20] Cvjetovi pužućeg čička privlače mnoge insekte (polinacijski sindrom).[21]
Kao i kod drugih vrsta roda Cirsium, korijeni su jestivi iako se rijetko koriste, ne samo zbog svoje sklonosti da podstiče nadutost kod nekih ljudi. Debeli korijen se smatra najhranjivijim. Listovi su jestivi iako su bodlje u pripremi za hranu previše dosadne da bi bili korisni. Stabljike su jestive i trnovi se lakše skidaju.[22] Destilerija Bruichladdich sa Islay koristi pužući čičak kao jedan od sastojaka za destilaciju džina.[23] Peraste papuse pripadnici plemena Cherokee uzimaju kao projektile u duvaljkama kao strelice.[24]
Papus Cirsium arvense.
Cvjetajući Cirsium arvense.
Evropski češljugar (Carduelis carduelis) za uzimanje hrane puže na čičku.
Mikrografija pod elektronskim skenirajučim mikroskopom: Aceria anthocoptes, potencijalni biološki kontrolni agens sjemenki u Kanadi.
Pužući čičak (latinski: Cirsium arvense) – poznat i kao čičak palamida – je cvjetnica roda Cirsium, koja prirodno raste širom Evrope i Sjeverne Azije, a drugdje je široko unesena vrsta.
Li tcherdon d' tchamp (on dit eto : tcherdon di tchvå, blanc tcherdon), c' est ene sôre di tcherdon, ki l' bodje et les foyes sont påle vete di coleur, ki crexhe dins les tchamps, et k' est et magnî voltî des tchvås.
C' est l' pus cmon des tcherdons d' Walonreye.
No d' l' indje e sincieus latén : Cirsium arvense
C' est ene plante 30 a 150 cintimetes hôte.
Ele dene on måve flormint, ki tchaeke fleur est on tube.
Tote l' Urope, dizo 2000 metes di hôteur. Divnowe ene evayixhante indje e l' Izlande (la k' ele n' egzistéve nén).
Ele si mopleye pa ses grinnes, et eto pa des rampes, ki plèt viker d' ene anêye a l' ôte.
Elle est loukêye come crouwå. Divinltins, el Beldjike,ele diveut esse discrouwådêye divant l' 15 di may.
foyes
fleurs
grinnîs
grinnes avou leu ploumtion
grinne
_-_geograph.org.uk_-_213840.jpg)
Pol discramiaedje des årtikes avou l' mot "tcherdon", loukîz cial Li tcherdon d' tchamp (on dit eto : tcherdon di tchvå, blanc tcherdon), c' est ene sôre di tcherdon, ki l' bodje et les foyes sont påle vete di coleur, ki crexhe dins les tchamps, et k' est et magnî voltî des tchvås.
C' est l' pus cmon des tcherdons d' Walonreye.
No d' l' indje e sincieus latén : Cirsium arvense
Баҫыу билсәне (урыҫ.Бодя́к полево́й, йәки Ро́зовый осо́т, лат. Cirsium arvense)- ҡатмарлы сәскәлеләр ғаиләһенә ингән сәнскәк япраҡлы ҡый үләне. Бал ҡорттары уның татын да, һеркәһен дә яратып йыя.
Баҫыу билсәне (урыҫ.Бодя́к полево́й, йәки Ро́зовый осо́т, лат. Cirsium arvense)- ҡатмарлы сәскәлеләр ғаиләһенә ингән сәнскәк япраҡлы ҡый үләне. Бал ҡорттары уның татын да, һеркәһен дә яратып йыя.
Паксянь чудожов[1] (лат. Cirsium arvense, руз. Бодя́к полево́й, или Ро́зовый осо́т) — ламоиень тикшень касовкс Чудожовонь буень (Círsium), Вейсэндявозь цецянсетнень раськесь (Asteraceae, эли Compositae).
Лопанзо теить ундоксонь пурнавкс, конастонть касы нетькс 30-нь см-сто 200-нь см-ас; верьга нетьксэсь тарадыы. Цеци — аштемковсто ожоковс. Паксянь чудожовось — пек а изнявиця пакся тикше кшинь сюронь касовксо, пирева ды од вирень касовкска. Виев пезэмкс ладсо ундоксозо сови модас 2—3 метрас, коли коли вастневить ундокст 5—6 метрань кувалмосо. 35 см-со прявт ундокстонть эйстэ туи эчкев ундоксонь пурнавкс, эйсэнзэ пурнави тикшенть ярсамопелезэ.
Цецятнестэ мекштне саить парсте медярво[2].
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ванмо
Паксянь чудожов (лат. Cirsium arvense, руз. Бодя́к полево́й, или Ро́зовый осо́т) — ламоиень тикшень касовкс Чудожовонь буень (Círsium), Вейсэндявозь цецянсетнень раськесь (Asteraceae, эли Compositae).
Лопанзо теить ундоксонь пурнавкс, конастонть касы нетькс 30-нь см-сто 200-нь см-ас; верьга нетьксэсь тарадыы. Цеци — аштемковсто ожоковс. Паксянь чудожовось — пек а изнявиця пакся тикше кшинь сюронь касовксо, пирева ды од вирень касовкска. Виев пезэмкс ладсо ундоксозо сови модас 2—3 метрас, коли коли вастневить ундокст 5—6 метрань кувалмосо. 35 см-со прявт ундокстонть эйстэ туи эчкев ундоксонь пурнавкс, эйсэнзэ пурнави тикшенть ярсамопелезэ.
Цецятнестэ мекштне саить парсте медярво.
Cirsium arvense - e dua na vu ni kau.
Cirsium arvense is a perennial species of flowering plant in the family Asteraceae, native throughout Europe and western Asia, northern Africa and widely introduced elsewhere.[2][3][4][5] The standard English name in its native area is creeping thistle.[6] It is also commonly known as Canada thistle and field thistle.[7][8]
The plant is beneficial for pollinators that rely on nectar. It also was a top producer of nectar sugar in a 2016 study in Britain, with a second-place ranking due to a production per floral unit of (2609±239 μg).[9]
A number of other names are used in other areas or have been used in the past, including: Canadian thistle, lettuce from hell thistle, California thistle,[10] corn thistle, cursed thistle, field thistle, green thistle, hard thistle, perennial thistle, prickly thistle, setose thistle, small-flowered thistle, way thistle, and stinger-needles. Canada and Canadian thistle are in wide use in the United States, despite being a misleading designation (it is not of Canadian origin).[11]
Cirsium arvense is a C3 carbon fixation plant.[12] The C3 plants originated during Mesozoic and Paleozoic eras, and tend to thrive in areas where sunlight intensity is moderate, temperatures are moderate, and ground water is plentiful. C3 plants lose 97% of the water taken up through their roots to transpiration.[13]
Creeping thistle is a herbaceous perennial plant growing up to 150 cm, forming extensive clonal colonies from thickened roots that send up numerous erect shoots during the growing season.[14] It is a ruderal species.[15]
Given its adaptive nature, Cirsium arvense is one of the worst invasive weeds worldwide. Through comparison of its genetic expressions, the plant evolves differently with respect to where it has established itself. Differences can be seen in their R-protein mediated defenses, sensitivities to abiotic stresses, and developmental timing.[16]
Cirsium arvense is placed in the subtribe Carduinae, tribe Cardueae of the family Asteraceae. Unlike other species in the same genus, it is dioecious, although male plants sometimes produce bisexual flowers.[17] It also differs from other native North American species in having large roots and multiple small flower heads on a branched stem.[18]
Its underground structure consists of four types, 1) long, thick, horizontal roots, 2) long, thick, vertical roots, 3) short, fine shoots, and 4) vertical, underground stems.[19] Though asserted in some literature, creeping thistle does not form rhizomes.[20] Root buds form adventitiously on the thickened roots of creeping thistle, and give rise to new shoots. Shoots can also arise from the lateral buds on the underground portion of regular shoots, particularly if the shoots are cut off through mowing or when stem segments are buried.[20]
Stems are 30–150 cm, slender green, and freely branched,[20] smooth and glabrous (having no trichomes or glaucousness), mostly without spiny wings. Leaves are alternate on the stem with their base sessile and clasping or shortly decurrent. The leaves are very spiny, lobed, and up to 15–20 cm long and 2–3 cm broad (smaller on the upper part of the flower stem).
Every plant species has a unique floral fragrance.[21] The fragrance that C. arvense emits attracts both pollinators and florivores containing compounds that attract each respectively. Non-native honeybees are shown to have the highest visitation rate, following other bee species in the genera Halictus and Lasioglossum. Hover flies are also commonly seen pollinating the flower heads of this plant.[22] Florivores such as beetles and grasshoppers are commonly seen as well. The compounds found in the fragrance may not be in the highest abundance but they are highly attractive. P-anisaldehyde is found in less than 1%, yet it attracts pollinators such as honey bees.[23] This is thought to be the result of additive and synergistic effects from the blend increasing the attraction to the plant. After pollination, it can be seen that fragrance emission decreases in C.arvense. This is regulated through a regulatory feedback mechanism depending on the pollination status of the plant. This mechanism has only been observed in pistillate plants for dioecious C. arvense. Fragrance emission increases with age.[24]
The fragrance contains several compounds that attract diverse insects. Looking at certain butterflies species, it can be seen that the fragrance blend is highly attractive to them, being sensitive to their antennae. High antennal response are seen in consequence to the phenylacetaldehyde as well as the terpenes (oxoisophoroneoxide, oxoisophorone, and dihydrooxoisophorone) found in the blend. This was seen in both natural plants emitting the fragrance and emitting the scent synthetically.[25] It is believed that general arousal can be stimulated through exposure of a single compound, whereas the accumulated exposure of all the compounds influence the foraging behaviour of the butterflies.[21]
The inflorescence compound cyme is 10–22 mm (0.39–0.87 in) in diameter, pink-purple, with all the florets of similar form (no division into disc and ray florets). The flowers are usually dioecious, but not invariably so, with some plants bearing hermaphrodite flowers.[20] The seeds are 4–5 mm long, with a feathery pappus which assists in wind dispersal.[26][27][28] One to 5 flower heads occur per branch, with plants in very favourable conditions producing up to 100 heads per shoot.[14] Each head contains an average of 100 florets. Average seed production per plant has been estimated at 1530. More seeds are produced when male and female plants are closer together, as flowers are primarily insect-pollinated.[14] The plant can bloom from seed in a year then subsequently the seeds produced can emerge in the following year.[29]
.jpg)
Pappus of Cirsium arvense
A creeping thistle with a "cuckoo spit"
Variation in leaf characters (texture, vestiture, segmentation, spininess) is the basis for determining creeping thistle varieties.[14] According to Flora of Northwest Europe[26] the two varieties are:
The Biology of Canadian Weeds: Cirsium arvense[14] list four varieties:
The seeds are an important food for the goldfinch and the linnet, and to a lesser extent for other finches.[30] Creeping thistle foliage is used as a food by over 20 species of Lepidoptera, including the painted lady butterfly and the engrailed moth, and several species of aphids.[31][32][33]
The flowers are visited by a wide variety of insects such as bees, moths, wasps and beetles[34] (the generalised pollination syndrome).[35]
The species is widely considered a weed even where it is native, for example being designated an "injurious weed" in the United Kingdom under the Weeds Act 1959.[36] It is also a serious invasive species in many additional regions where it has been introduced, usually accidentally as a contaminant in cereal crop seeds. It is cited as a noxious weed in several countries; for example Australia, Brazil, Canada, Ireland, New Zealand, and the United States. Many countries regulate this plant, or its parts (i.e., seed) as a contaminant of other imported products such as grains for consumption or seeds for propagation. In Canada, C. arvense is classified as a primary noxious weed seed in the Weed Seeds Order 2005 which applies to Canada's Seeds Regulations.[37]
Control methods include cutting at flower stem extension before the flower buds open to prevent seed spread. Repeated cutting at the same growth stage over several years may "wear down" the plant.
Growing forages such as alfalfa can help control the species as a weed by frequently cutting the alfalfa to add nutrients to the soil, the weeds also get cut, and have a harder time re-establishing themselves, which reduces the shoot density.[38]
Orellia ruficauda feeds on Canada thistle and has been reported to be the most effective biological control agent for that plant.[39] Its larvae parasitize the seed heads, feeding solely upon fertile seed heads.[40]
The weevil Larinus planus also feeds on the thistle and has been used as a control agent in Canada.[41] One larva of the species can consume up to 95% of seeds in a particular flower bud.[42] However, use of this weevil has had a damaging effect on other thistle species as well, include some that are threatened.[43] It may therefore not be a desirable control agent. It is unclear if the government continues to use this weevil to control Canada thistles or not.
The rust species Puccinia obtegens has shown some promise for controlling Canada thistle, but it must be used in conjunction with other control measures to be effective.[44] Also Puccinia punctiformis is used in North America and New Zealand in biological control.[45] In 2013, in four countries in three continents, epidemics of systemic disease caused by this rust fungus could be routinely and easily established.[46] The procedure for establishing this control agent involves three simple steps and is a long-term sustainable control solution that is free and does not involve herbicides. Plants systemically diseased with the rust gradually but surely die. Reductions in thistle density were estimated, in 10 sites in the U.S., Greece, and Russia, to average 43%, 64%, and 81% by 18, 30, and 42 months, respectively, after a single application of spores of the fungus.[47]
Aceria anthocoptes feeds on this species and is considered to be a good potential biological control agent.
Applying herbicide: Herbicides dominated by phenoxy compounds (especially MCPA) caused drastic declines in thistle infestation in Sweden in the 1950s.[12] MCPA and clopyralid are approved in some regions. Glyphosate is a non-selective herbicide that can be used when the plant has grown a few inches tall, where the herbicide can be absorbed by the leaf surfaces.[29]
Crop tolerance and weed control ratings were conducted in the spring of 2012, and the Prepass herbicide by DOW AgroSciences was found to be most effective at controlling the species as a weed problem in alfalfa fields.[48]
Like other Cirsium species, the roots are edible, though rarely used, not in the least because of their propensity to induce flatulence in some people. The taproot is considered the most nutritious part. The leaves are also edible, though the spines make their preparation for food too tedious to be worthwhile. The stalks, however, are also edible and more easily despined.[49] Bruichladdich distillery on Isle of Islay lists creeping thistle as one of the 22 botanical forages used in their gin, The Botanist.[50]
The feathery pappus is also used by the Cherokee to fletch blowgun darts.[51]
Cirsium arvense is a perennial species of flowering plant in the family Asteraceae, native throughout Europe and western Asia, northern Africa and widely introduced elsewhere. The standard English name in its native area is creeping thistle. It is also commonly known as Canada thistle and field thistle.
The plant is beneficial for pollinators that rely on nectar. It also was a top producer of nectar sugar in a 2016 study in Britain, with a second-place ranking due to a production per floral unit of (2609±239 μg).
Cirsium arvense (cardo cundidor) es una planta de la familia de las asteráceas.
Erecta, vivaz, con tallos muy ramosos, foliosos, no alados de hasta 1.5 m, y con estolones rastreros largos de brotes foliosos. Hojas lanceoladas a oblongas, enteras o divididas con lóbulos trinagulares espinosos, glabras o con pelos como de telaraña. 1-5 capítulos morado claro, de 1.5-3 cm de largo, de cabillo corto, con el ápice de las ramas. Brácteas involucrales violeta oscuro, erectas, las externas, romas. Flores pentalobuladas, con largo tubo corolino. Especie muy variable. Florece en el verano.[1]
Campos de labranza, pastos, tierras baldías, claros en el bosque.
Toda Europa. Introducido en Islandia y en Norteamérica en donde es una plaga. La mosca de los cardos, Urophora cardui, ha sido introducida intencionalmente como control biológico.
Tiene propiedades astringentes.
Se utiliza también la planta entera externamente en forma de baños contra las hemorroides.[2]
Cirsium arvense fue descrito primero por Carlos Linneo como Serratula arvensis y publicado en Species Plantarum, vol. 2, p. 820 [1], 1753 y, ulteriormente, clasificado en el género Cirsium por Giovanni Antonio Scopoli y publicado en Flora Carniolica, Editio Secunda, vol. 2, pp. 126-127, 1772.[3]
Número de cromosomas de Cirsium arvense (Fam. Compositae) y táxones infraespecíficos: 2n=34[4]
Cirsium: nombre genérico que deriva de la palabra latina cirsĭŏn, -ĭi —del griego χιρσός, -ον, varices— vocablo que usa Plinio el Viejo (Naturalis Historia, 27, 61) para identificar un cardo que se utiliza para el tratamiento de este tipo de dolencia. En los tiempos modernos, el botánico francés Tournefort (1656-1708) ha derivado el nombre Cirsium.
arvense: epíteto latino derivado de arvus, -a, -um que significa "de los campos".[5]
Cirsium arvense (cardo cundidor) es una planta de la familia de las asteráceas.
Põldohakas (Cirsium arvense) on korvõieliste sugukonda ohaka perekonda kuuluv kaheaastane rohttaim.
Põldohakas kasvab niiskematel niitudel ja puisniitudel, metsasihtidel ja -servadel ning veekogude kallastel.
Põldohakas (Cirsium arvense) on korvõieliste sugukonda ohaka perekonda kuuluv kaheaastane rohttaim.
Põldohakas kasvab niiskematel niitudel ja puisniitudel, metsasihtidel ja -servadel ning veekogude kallastel.
Pelto-ohdake (Cirsium arvense) on piikikäs asterikasvi. Se kasvaa noin 120 cm:n pituiseksi. Sen pariliuskaiset lehdet ovat reunoiltaan syvään hampaiset, hampaat ovat piikkimäiset ja piikit jopa 5 mm pitkät. Sen vaaleanpunaiset tai liilat kukinnot ovat kasvin latvassa useina mykeröinä. Kussakin mykerössä on satoja kukkia. Hede- ja emikukat ovat erikseen. Kukat ovat voimakkaasti tuoksuvia ja hyönteispölytteisiä. Perhosista esimerkiksi ohdakeperhonen (Vanessa cardui) munii pelto-ohdakkeen lehdille. Kasvi on yleensä Suomessa muinaistulokas ja uustulokas Pohjois-Suomessa Perämeren rannalla.
Pelto-ohdake kukkii Suomessa heinäkuulta syyskuulle. Siemenet ovat 4–5 millimetriä pitkiä ja leviävät tuulen mukana. Siemenet voivat lenninhaivenien (pappus) avulla levitä useiden kilometrien päähän emokasvistaan. Pelto-ohdakkeen tavallisimpia kasvupaikkoja ovat tienreunat, pellot ja niityt mutta se on yleinen myös esimerkiksi meren rannoilla.
Pelto-ohdakkeen koossa, lehtien muodossa ja kukintojen koossa esiintyy runsasta muuntelua. Lisäksi pelto-ohdake risteytyy lähisukulaistensa kanssa.[1]
Pelto-ohdake lisääntyy voimakkaasti kasvullisesti juurtensa avulla, jotka levittäytyvät usein horisontaalisesti laajalle, mutta myös vertikaalisesti jopa kahden metrin syvyyteen. Pelto-ohdaketta pidetään sen voimakkaan kasvullisen lisääntymisen takia vaikeasti hävitettävänä rikkakasvina. Pelto-ohdake on menestyvä kilpailija, joka sietää hyvin häiriöitä ja leviää esimerkiksi maanmuokkausvälineiden mukana. Pienikin juurenpala riittää uuden kasviyksilön syntymiseen.[2]
Pelto-ohdake (Cirsium arvense) on piikikäs asterikasvi. Se kasvaa noin 120 cm:n pituiseksi. Sen pariliuskaiset lehdet ovat reunoiltaan syvään hampaiset, hampaat ovat piikkimäiset ja piikit jopa 5 mm pitkät. Sen vaaleanpunaiset tai liilat kukinnot ovat kasvin latvassa useina mykeröinä. Kussakin mykerössä on satoja kukkia. Hede- ja emikukat ovat erikseen. Kukat ovat voimakkaasti tuoksuvia ja hyönteispölytteisiä. Perhosista esimerkiksi ohdakeperhonen (Vanessa cardui) munii pelto-ohdakkeen lehdille. Kasvi on yleensä Suomessa muinaistulokas ja uustulokas Pohjois-Suomessa Perämeren rannalla.
Pelto-ohdake kukkii Suomessa heinäkuulta syyskuulle. Siemenet ovat 4–5 millimetriä pitkiä ja leviävät tuulen mukana. Siemenet voivat lenninhaivenien (pappus) avulla levitä useiden kilometrien päähän emokasvistaan. Pelto-ohdakkeen tavallisimpia kasvupaikkoja ovat tienreunat, pellot ja niityt mutta se on yleinen myös esimerkiksi meren rannoilla.
Pelto-ohdakkeen koossa, lehtien muodossa ja kukintojen koossa esiintyy runsasta muuntelua. Lisäksi pelto-ohdake risteytyy lähisukulaistensa kanssa.
Pelto-ohdake lisääntyy voimakkaasti kasvullisesti juurtensa avulla, jotka levittäytyvät usein horisontaalisesti laajalle, mutta myös vertikaalisesti jopa kahden metrin syvyyteen. Pelto-ohdaketta pidetään sen voimakkaan kasvullisen lisääntymisen takia vaikeasti hävitettävänä rikkakasvina. Pelto-ohdake on menestyvä kilpailija, joka sietää hyvin häiriöitä ja leviää esimerkiksi maanmuokkausvälineiden mukana. Pienikin juurenpala riittää uuden kasviyksilön syntymiseen.
Chardon des champs, Cirse des champs
Cirsium arvense, en français Chardon des champs ou Cirse des champs, est une espèce de plante vivace du genre Cirsium et de la famille des Astéracées (ou Composées). Très commune dans toute l'Europe, c'est une plante nitrophile, adventice de la plupart des cultures, des prairies, se multipliant rapidement par ses nombreuses graines qui, grâce à leurs aigrettes, peuvent être disséminées à grande distance. On le reconnaît entre autres à ses capitules lilas dont les fleurons (fleurs tubulées) s'épanouissent largement.
En plus de ses noms recommandés ou typiques « Chardon des champs »[2] ou « Cirse des champs »[3], l'espèce est également nommée en français « Chardon du Canada »[2], « Chardon des vignes »[3], « Herbe aux varices »[3] ou « Sarette »[3].
C’est une plante dressée de 50 à 130 centimètres de haut et pouvant parfois atteindre 150 centimètres. Sa tige est très rameuse, elle a la particularité de ne presque pas porter d’épines et de ne pas être ailée. Les feuilles sont allongées, découpées et bordées de dents épineuses, vertes et glabres sur les deux faces ou présentant une pilosité blanchâtre sur la face inférieure [4].
Les fleurs sont toutes en tubes en petits capitules ovoïdes entourées de bractées peu épineuses (ce genre d’inflorescence est appelé racème de capitules). La couleur des capitules peut varier du pourpre au blanc, en passant par plusieurs nuances de rose[5]. Les fruits sont des akènes munis d’une aigrette blanche et plumeuse.
Le système racinaire du Cirse des champs est composé des rhizomes horizontaux servant d’organes de réserve et des racines verticales qui peuvent descendre à plus de 2 mètres de profondeur servant à capter l’eau et les nutriments.
Cirsium arvense peut être confondu avec d’autres espèces du genre Cirsium, en particulier le Cirse des ruisseaux (Cirsium rivulare). Il s'en distingue par l’absence de rosette basale de feuilles et surtout ses fleurs unisexuées sur un même capitule. Les espèces du genre Carduus, également proches, présentent des akènes sans soies plumeuses[1].
Le Cirse des champs est d’origine eurasiatique et est très commun dans toute l’Europe, on le retrouve également désormais dans d’autres pays. Il a été introduit aux États-Unis [6] et au Canada[7] au début du XVIIe siècle et est considéré comme invasif dans ces deux pays. Le Cirse des champs est une plante qui peut s’adapter à de nombreux milieux, mais qui préfère les milieux riches et ensoleillés. On le retrouve dans les prairies, sur les bords de chemins et de routes, dans les friches, les champs et les jardins.
Le chardon des champs est une plante géophyte qui passe l’hiver sous forme de racine et débourre au printemps [4].
Le Cirse des champs est une plante dioïque avec des pieds mâles pouvant féconder des pieds femelles jusqu'à cent mètres à la ronde. La période de floraison s’étale de juillet à septembre. Ce chardon émet des COV floraux qui attirent ses pollinisateurs mais aussi ses ennemis naturels, ne pouvant ainsi favoriser à la fois sa reproduction et sa défense contre les herbivores[8]. Même pour les humains, l'odeur émise par les capitules est agréable[9].
Chaque plant de chardons peut produire 5 000 à 40 000 graines dont 200 à 300 seulement peuvent germer, les graines gardent leur potentiel germinatif jusqu’à 20 ans. Les semences peuvent voler de 30 à 150 mètres de la plante mère[10]. Les graines sont dispersées par le vent (anémochorie).
Les racines horizontales ou rhizomes portent des bourgeons dont une partie va donner (dès la fin de l’hiver) des drageons qui vont ensuite pouvoir donner de nouveaux pieds de chardons. La croissance horizontale par les racines peut atteindre 4 ou 5 mètres par an, le chardon forme ainsi des ronds. Si les racines sont coupées en fragments, chaque fragment peut donner naissance en quelques jours à un nouveau plant. De nouvelles pousses peuvent émerger à partir de fragments de 2,5 cm[7]. La prolifération de ce chardon est avant tout due à son système racinaire extrêmement vigoureux et un développement par tâche pouvant s'étendre de 1 à 2 m/an[11].
Plusieurs chenilles, dont celles de la belle-dame (aussi appelé Vanesse du chardon), dévorent cette plante, ainsi que des mouches et plus d’une dizaine de coléoptères : coccinelles phytophages, charançons et chrysomèles sans oublier les punaises. Par exemple, la larve de l’agapanthie du chardon (Agapanthia cardui), un longicorne, se nourrit de l'intérieur des tiges de ce chardon. Les graines sont également une réserve de nourriture intéressante pour les espèces d’oiseaux granivores comme le chardonneret. Le Cirse des champs, tout comme les autres espèces de chardons, est aussi très recherché par les abeilles qui y récoltent du pollen et un nectar abondant.
Cette plante, localement envahissante, fait l'objet de diverses mesures de contrôle par les agriculteurs et collectivités ou jardiniers.
Cependant, selon Gérard Ducerf, elle serait bio-indicatrice des sols saturés par des amendements excessifs en engrais azotés et en fumiers non compostés ou par surpâturage, ce qui provoquerait un blocage de la potasse ; la plante jouerait son rôle écologique naturel en venant ainsi au "secours" des sols afin d'en rétablir l'équilibre biologique. Ce serait enfin une plante médicinale extrêmement utile pour soigner les carences en phosphore et les intoxication à l'aluminium générés par les déséquilibres des sols tassés et lessivés par les méthodes de l'agriculture mécanisée et intensive[12].
Le Cirse des champs fait partie des adventices les plus souvent trouvées dans les cultures[13]. Il se répand très rapidement dans les champs grâce à son système racinaire et forme des "taches" de chardons. Une fois qu’une colonie de chardons est établie, il est difficile de s’en débarrasser en raison du potentiel de régénération et d'accumulation rapide de réserves dans les racines. L’envahissement d’une culture par le Cirse des champs peut entraîner une perte de rendement, des études ont montré qu’une densité de chardons de 16 plants au m² diminue le rendement de blé tendre de 19 %[14] et celui de fèves de 12 %[15]. Le chardon des champs (Cirsium arvense) figure dans la liste des organismes nuisibles contre lesquels la lutte peut être rendue obligatoire dans certaines conditions (annexe B de l'arrêté ministériel du 31 juillet 2000)[16]. Dans plusieurs départements, des arrêtés préfectoraux rendent obligatoire la lutte contre le Cirse des champs.
Diverses méthodes de lutte peuvent être utilisées contre le Cirse des champs. La lutte chimique est la méthode la plus souvent employée en agriculture conventionnelle, plusieurs herbicides étant recommandés, comme le 2,4-D, le triclopyr, le glyphosate, le dicamba, ou des produits à base de clopyralid, efficaces pour le contrôle du Cirse des champs. Les méthodes de lutte mécanique comprennent les fauches répétées, l’arrachage manuel, le déchaumage et le brûlage des plants. Ces méthodes doivent être poursuivies pendant plusieurs années, et répétées de nombreuses fois pour arriver à un contrôle correct des populations de Cirse des champs. Sur certains sites, l’implantation de bâches ou de géotextiles a aussi été testée avec des résultats assez mitigés[7]. Concernant le contrôle biologique, plusieurs agents de contrôle ont été lâchés en Amérique pour tenter de réguler les populations, notamment des coléoptères tels que Cassida rubiginosa, des charançons tels que le mineur de tige Ceutorhynchus litura ou encore la mouche du chardon (Urophora cardui). Cependant, aucun de ces organismes ne semble réellement capable de contrôler les populations de cirses des champs[17]. D’autres pathogènes, comme des champignons ou encore des bactéries, ont été testés, mais sans résultats convaincants.
Cirsium arvense a pour synonymes[18] :
Chardon des champs, Cirse des champs
Cirsium arvense, en français Chardon des champs ou Cirse des champs, est une espèce de plante vivace du genre Cirsium et de la famille des Astéracées (ou Composées). Très commune dans toute l'Europe, c'est une plante nitrophile, adventice de la plupart des cultures, des prairies, se multipliant rapidement par ses nombreuses graines qui, grâce à leurs aigrettes, peuvent être disséminées à grande distance. On le reconnaît entre autres à ses capitules lilas dont les fleurons (fleurs tubulées) s'épanouissent largement.
Þistill (fræðiheiti: Cirsium arvense) er stórvaxin fjölær jurt af körfublómaætt með litlum fjólubláum blómum. Blöðin eru þyrnótt á röndunum. Tegundin er víða flokkuð sem illgresi. Þistill er innfluttur slæðingur á Íslandi.
Þistill (fræðiheiti: Cirsium arvense) er stórvaxin fjölær jurt af körfublómaætt með litlum fjólubláum blómum. Blöðin eru þyrnótt á röndunum. Tegundin er víða flokkuð sem illgresi. Þistill er innfluttur slæðingur á Íslandi.
Il cardo campestre (Cirsium arvense (L.) Scop., 1771) è una pianta angiosperma dicotiledone appartenente alla famiglia delle Asteraceae, nativa dell'area mediterranea.[1][2]
Il nome del genere (cirsium) deriva dalla parola greca kirsos = varice; da questa radice deriva poi la denominazione Kirsion, un vocabolo che sembra servisse ad identificare una pianta usata per curare questo tipo di malattia. Da kirsion in tempi moderni il botanico francese Tournefort (1656 - 708) derivò il nome Cirsium dell'attuale genere.[3][4]
Il nome italiano “cardo” è abbastanza generico in quanto nel linguaggio comune si riferisce a diversi generi e specie di piante. Tra i generi che vengono chiamati direttamente “cardo”, oppure hanno una o più specie che comunemente si chiamano con questo nome citiamo: Carduus, Carduncellus, Carlina, Centaurea, Cnicus, Cynara, Echinops, Galactites, Jurinea, Onopordum, Scolymus, Silybum, Tyrimnus, tutti della famiglia delle Asteraceae. Ma anche in altre famiglie abbiamo dei generi con delle specie che volgarmente vengono chiamate “cardi” : il genere Eryngium della famiglia delle Apiaceae o il genere Dipsacus della famiglia delle Dipsacaceae.
Il binomio scientifico della pianta di questa voce è stato proposto inizialmente da Carl von Linné (1707 – 1778) biologo e scrittore svedese, considerato il padre della moderna classificazione scientifica degli organismi viventi, perfezionato successivamente dal medico e naturalista italiano Giovanni Antonio Scopoli (Cavalese, 3 giugno 1723 – Pavia, 8 maggio 1788) nella pubblicazione ”Flora Carniolica Exhibens Plantas Carniolae Indigenas et Distributas in Classes Naturales cum Differentiis Specificis, Synonymis Recentiorum, Locis Natalibus, Nominibus Incolarum, Observationibus Selectis, Viribus Medicis. Editio Secunda Aucta et Reformata. Viennae” del 1771.[5]
L'epiteto specifico (arvense = campestre) e quello comune deriva dall'origine ecologica della pianta.[6]
Le specie di questa voce è una pianta perenne con portamento erbacei. Nelle radici sono sempre presenti dei condotti resinosi, meno frequenti nelle parti aeree; mentre solamente nelle parti aeree sono presenti delle cellule latticifere. La forma biologica è geofita radicigemmate (G rad), sono piante perenni con organi sotterranei portanti gemme, dalle quali annualmente si sviluppano le parti aeree.[7][8][9][10][11][12]
Il fusto, eretto, solcato longitudinalmente (strie purpuree), pubescente o tomentoso nella parte apicale, può raggiungere 1-1,5 m di altezza. Nella parte ipogea è presente un rizoma. La ramosità si presenta solamente nella metà superiore.
Le foglie, pennato-lobate (ossia pennatopartite con 5 - 7 coppie di lacinie per lato), pubescenti, sono lunghe sino a 8 – 15 cm e larghe 2 – 3 cm e presentano un margine dentato-spinoso. Alla base le foglie sono cuneate e non sono decorrenti. Lungo il caule sono disposte in modo alterno.
Le infiorescenze (composte da capolini più o meno peduncolati) sono scapose. I capolini, discoidi e omogami e privi di foglie bratteali, sono formati da un involucro piriforme arrossato composto da brattee (o squame) disposte su più serie all'interno delle quali un ricettacolo fa da base ai fiori solamente femminili ovvero maschili. Le squame dell'involucro, di tipo fogliaceo o membranoso, sono disposte in modo embricato e scalato; in genere all'apice sono spinose con punte rivolte all'infuori. Il ricettacolo, provvisto di pagliette a protezione della base dei fiori, può essere rivestito di pula (come il chicco del grano o del riso), oppure può essere setoloso, raramente è nudo (senza pagliette). Diametro dei capolini: minore di 2 cm. Dimensione dell'involucro: larghezza 8 mm; lunghezza 12 mm.
I fiori in genere sono tubulosi (del tipo actinomorfi)[13], e sono tetra-ciclici (ossia sono presenti 4 verticilli: calice – corolla – androceo – gineceo) e pentameri (ogni verticillo ha 5 elementi). I fiori sono unisessuali.
, [C (5), A (5)], G 2 (infero), achenio[14]
Il frutto è un achenio con un pappo. Le forme dell'achenio possono essere obovoidi-fusiformi, compresse lateralmente, con areole a inserzione diritta o laterale-abassiale. Il pericarpo dell'achenio possiede delle sclerificazioni radiali spesso provviste di protuberanze. Il pappo è inserito su una piastra apicale all'interno di una anello di tessuto parenchimatico. Le setole del pappo sono disposte su una o più serie e sono decidue come un pezzo unico e si presentano piumose e colorate di bianco-sporco. Lunghezza dell'achenio: 2 mm. Lunghezza del pappo: 10 mm.
Dal punto di vista fitosociologico alpino la specie di questa voce appartiene alla seguente comunità vegetale:[17]
Per l'areale completo italiano la specie di questa voce appartiene alla seguente comunità vegetale:[18]
Descrizione. L'alleanza Dauco carotae-Melilotion albi è relativa alle comunità ruderali nitrofile di specie erbacee con cicli biologici bienni e perenni su suoli aridi e poveri di nutrienti con elevato contenuto di ghiaia e detriti. Questa alleanza è distribuita nell’Europa centrale da cui si è in seguito diffusa tramite mezzi antropogenici (strade, ferrovie e spostamenti umani).
Specie presenti nell'associazione: Oenothera biennis, Reseda lutea, Cichorium intybus, Cirsium arvense, Verbascum densiflorum, Verbascum nigrum, Achillea millefolium, Artemisia vulgaris, Elytrigia repens, Pastinaca sativa subsp. urens, Reseda lutea, Melilotus albus, Melilotus officinalis, Linaria vulgaris, Medicago sativa, Erigeron annuus, Erysimum hieracifolium, Saponaria officinalis, Solidago canadensis, Crepis rhoeadifolia e Crepis setosa.
I semi del C. arvense sono un'importante fonte di cibo per cardellini, fanelli ed altre specie di fringillidi[19].
Le foglie fungono da nutrimento per le larve di oltre 20 specie di farfalle, tra cui Vanessa cardui e Ectropis crepuscularia, e per numerose specie di afidi[20][21][22].
C. arvense, così come altri rappresentanti delle Asteraceae (Centaurea spp., Carduus spp., Galactites spp., Jurinea spp., Pallenis spp., ecc.) fiorisce durante l'estate, in gruppi di più individui, entrando a far parte di biocenosi di tipo mesofilo, (ad esempio i prati alpini), in cui assume una notevole rilevanza ecologica; le infiorescenze nettarifere delle specie sopra citate, che presentano tutte tonalità solitamente comprese tra il rosa e il viola carico, risultano fortemente attrattive per gli adulti di varie specie di farfalle, tra cui Nymphalidae (p.e. Vanessa spp.), Papilionidae (p.e. Iphiclides spp.) e diverse specie della famiglia Pieridae.
Ad esempio si è notata una predilezione per le infiorescenze di Cirsium arvense da parte degli adulti di Pieris napi, oltre che Pieris brassicae e Pieris mannii. Questa capacità attrattiva (che però non è da ritenersi specie-specifica) può essere spiegata sia con la produzione, da parte della pianta, di oli ed essenze particolarmente appetibili per la farfalla, sia con la peculiare gamma cromatica, che orienta l'insetto durante la ricerca del nettare.
La famiglia di appartenenza di questa voce (Asteraceae o Compositae, nomen conservandum) probabilmente originaria del Sud America, è la più numerosa del mondo vegetale, comprende oltre 23.000 specie distribuite su 1.535 generi[23], oppure 22.750 specie e 1.530 generi secondo altre fonti[24] (una delle checklist più aggiornata elenca fino a 1.679 generi)[25]. La famiglia attualmente (2021) è divisa in 16 sottofamiglie.[1][10][26]
Cardueae è una delle 4 tribù della sottofamiglia. La tribù Cardueae a sua volta è suddivisa in 12 sottotribù (la sottotribù Carduinae è una di queste). Il genere Cirsium elenca 435 specie con una distribuzione cosmopolita, 35 delle quali sono presenti spontaneamente sul territorio italiano.[2][27][28][29][30][31]
Il genere di questa voce è inserito nel gruppo tassonomico della sottotribù Carduinae.[31] In precedenza provvisoriamente era inserito nel gruppo tassonomico informale "Carduus-Cirsium Group".[10] La posizione filogenetica di questo gruppo nell'ambito della sottotribù è abbastanza vicina al "core" della sottotribù (con il genere Carduus forma un "gruppo fratello") e dalle analisi molecolari è stato calcolato in 7,2 milioni di anni fa la separazione di questo genere dal resto del gruppo (è stato l'ultimo a separarsi).[29][30]
Il numero cromosomico di Cirsium arvense è 2n=34 e 68.[12][32]
I caratteri distintivi di questa specie nell'ambito del genere sono:[12][33]
Questi caratteri sono più o meno condivisi con le seguenti specie (tra parentesi sono indicati alcuni caratteri distintivi della specie):[33]
La specie di questa voce è variabile nei seguenti caratteri:[12]
Per questa specie sono indicate le seguenti varietà:[2]
Sono elencati alcuni sinonimi per questa entità:[2]
Il cardo campestre (Cirsium arvense (L.) Scop., 1771) è una pianta angiosperma dicotiledone appartenente alla famiglia delle Asteraceae, nativa dell'area mediterranea.
Dirvinė usnis (Cirsium arvense) – astrinių (Asteraceae) šeimos augalų rūšis, priklausanti usnių (Cirsium) genčiai. Natūraliai paplitusi Europoje ir šiaurės Azijoje.
Tai daugiametis žolinis augalas. Aukštis iki 1-1,2 m. Stiebas status arba gulsčias. Lapai spygliuoti, 15-20 cm ilgio. Žiedynas 10-22 mm skersmens, rausvas, dvinamis. Sėklos 4-5 cm ilgio, prikibusios prie pūko.
Dirvinė usnis įkyri piktžolė, auganti pievose, daržuose, pakelėse, tarp javų.
De akkerdistel (Cirsium arvense) is de in Nederland meest voorkomende vederdistel. De soortaanduiding arvense betekent akker. De Nederlandstalige naam komt dus overeen met de botanische naam.
De stengel van deze 60-120 cm hoge plant is niet of nauwelijks gevleugeld, en niet sterk vertakt. De stengel is in het bovenste deel niet gevleugeld. De plant heeft meestal meer dan vier bloemhoofdjes. De stengel groeit vanuit een wortelstok. De aan de bovenzijde donkergroene bladeren kunnen aan de onderzijde zilverig wit zijn. Aan de bovenzijde zijn ze kaal en glanzend.[1] De lancetvormige bladeren zijn gestekeld, en of veerspletig en gekroesd, of plat en ongedeeld. De bloemhoofdjes zijn langgesteeld in schermvormige pluimen, al is het schermvormige hiervan niet altijd even goed te herkennen. De bloemhoofdjes bloeien in een lichtpaarse, soms bijna witte kleur van juni tot en met september. De plant is vaak tweehuizig, waarbij de mannelijke bloemhoofdjes iets groter zijn dan de vrouwelijke bloemhoofdjes.[2] Het haar van de pappus is evenals bij andere vederdistels geveerd, dat wil zeggen van zijhaartjes voorzien. Hiervoor is wel een sterke loep nodig.[2] De omwindselbladen van het bloemhoofdje zijn afstaand maar niet teruggeslagen.[2]
De akkerdistel komt voor op open, vochtige, zeer voedselrijke, omgewerkte grond. De grond mag hierbij licht brak zijn. Hiernaast kan ze op droge voedselrijke bodem voorkomen. Ze behoort tot de plantengemeenschap Atriplici-Cirsietum arvensis.[2] De akkerdistel maakt ondergrondse stengels (rizomen). Stukjes rizoom kunnen weer een plant vormen, waardoor de plant een zeer lastig onkruid is. Ze wordt dan ook wel boerenplaag genoemd. De akkerdistel is te bestrijden door maaien vóór de bloei en door een akkerdistelvrije zone van 50 m tot akkerland of weiland aan te houden.[3] Landbouwers hebben veel last van akkerdistels in aangrenzende natuurgebieden. De plant wordt vanwege de aanwezige nectar door de honingbij, de kortsprietwespbij (Nomada fucata), de gewone koekoekshommel (Psithyrus campestris) en de aardhommel (Bombus terrestris) bezocht. Hiernaast bieden de lastig toegankelijke distelhaarden broedplaatsen aan meerdere vogelsoorten, onder meer putter, vink en veldleeuwerik.[4]
De vrucht van de akkerdistel bestaat uit een glad, bruin nootje met 2-3 cm lang haarkroontje
De omwindselbladen lopen uit in punten, die afstaand maar niet teruggeslagen zijn
Ook vlinders als de dagpauwoog komen graag op de nectar af
De gestekelde bladeren zijn plat en ongedeeld of veerspletig en gekroesd
Mediabestanden die bij dit onderwerp horen, zijn te vinden op de pagina Cirsium arvense op Wikimedia Commons. De akkerdistel (Cirsium arvense) is de in Nederland meest voorkomende vederdistel. De soortaanduiding arvense betekent akker. De Nederlandstalige naam komt dus overeen met de botanische naam.
Åkertistel (Cirsium arvense) er en kraftig plante med 50-130 cm høye, opprette stengler. Den kjennes spesielt på de stikkende tornene på bladene. Diameter på blomsterkurven er ca. 15-25 mm. Det er en liten fiolett blomst som blomstrer fra juli til september. Åkertistel anses som ugress.
Åkertistel (Cirsium arvense) er en kraftig plante med 50-130 cm høye, opprette stengler. Den kjennes spesielt på de stikkende tornene på bladene. Diameter på blomsterkurven er ca. 15-25 mm. Det er en liten fiolett blomst som blomstrer fra juli til september. Åkertistel anses som ugress.
Ostrożeń polny (Cirsium arvense (L.) Scop.) – gatunek rośliny wieloletniej należący do rodziny astrowatych.
Rodzimy obszar jego występowania to cała niemal Europa i znaczna część Azji[2]. Obecnie jednak jest gatunkiem kosmopolitycznym. Rozprzestrzenił się również na Azorach, w Australii i Nowej Zelandii, w Ameryce Północnej, na Hawajach i w niektórych rejonach Afryki i Ameryki Północnej[2]. W Polsce jest bardzo pospolity na całym obszarze. Status gatunku we florze Polski: gatunek autochtoniczny (rodzimy)[3].
Tworzy mieszańce z następującymi gatunkami: ostrożeń bezłodygowy (Cirsium acaule), ostrożeń błotny (Cirsium palustre), ostrożeń głowacz (Cirsium eriophorum), ostrożeń lancetowaty (Cirsium lanceolatum), ostrożeń lepki (Cirsium erisithales)[3].
Pasożytują na nim niektóre gatunki grzybów: Bremia lactucae, Erysiphe mayorii, Golovinomyces cichoracearum, Puccinia cnici, Puccinia punctiformis, Albugo tragopogonis, Ramularia cynarae, Ramularia cynarae emend, Phyllosticta cirsii i bakteria Pseudomonas syringae. Żerują na nim niektóre gatunki chrząszczy, muchówek, pluskwiaków[11].
Kwiatostan
Koszyczki ostrożnia polnego i zapylający je motyl
Dwie pszczoły na koszyczku ostrożnia polnego
Liść
Owoc
Przekrój koszyczka
W uprawach rolnych jest uciążliwym chwastem, szczególnie na pastwiskach. Rozmnaża się bardzo łatwo; każdy odcięty kawałek pędu może utworzyć nową roślinę. Na poziomych pędach podziemnych stale tworzy nowe pączki dające początek nowym pędom nadziemnym[8]. Próg szkodliwości gospodarczej we wszystkich uprawach waha się od 0,5-1,0 rośliny/m²[6].
Ostrożeń polny (Cirsium arvense (L.) Scop.) – gatunek rośliny wieloletniej należący do rodziny astrowatych.
O cardo-das-vinhas, cardo-hemorroidal ou cardo-rasteiro[1] (Cirsium arvense) é uma planta do género Cirsium, nativa da Europa, Ásia e norte de África, considerada espécie invasora e daninha no Brasil, Canadá e Estados Unidos.
É uma planta perene herbácea com raizes subterrâneas que lançam talos, alcançando 1-2 metros de altura. As folhas são muito espinhosas e lobuladas de até 20 cm de largura e 2–3 cm de largura. As inflorescências terminais têm um diâmetro de 1–2 cm e cor rosa púrpura. As sementes têm 4–5 mm de comprimento e possuem um penacho que facilita a sua disseminação pelo vento.
As sementes são um alimento importante para os pintassilgos e pintarroxos, e em menor escala para outros fringilídeos.[2] A sua folhagem serve de alimento a mais do que 20 espécies de lepidópteros, incluindo a borboleta bela-dama, e a Ectropis crepuscularia, e várias espécies de afídeos.[3][4][5]
Tal como outras espécies da família Cirsium, as raízes são comestíveis, ainda que raramente usadas, principalmente devido a sua tendência a originar flatulência em algumas pessoas. A raiz primária é considerada a mais nutritiva. As folhas são também comestíveis, ainda que os espinhos tornem a sua preparação para alimentação demasiadamente trabalhosa para valer a pena.[6]
O cardo-das-vinhas, cardo-hemorroidal ou cardo-rasteiro (Cirsium arvense) é uma planta do género Cirsium, nativa da Europa, Ásia e norte de África, considerada espécie invasora e daninha no Brasil, Canadá e Estados Unidos.
É uma planta perene herbácea com raizes subterrâneas que lançam talos, alcançando 1-2 metros de altura. As folhas são muito espinhosas e lobuladas de até 20 cm de largura e 2–3 cm de largura. As inflorescências terminais têm um diâmetro de 1–2 cm e cor rosa púrpura. As sementes têm 4–5 mm de comprimento e possuem um penacho que facilita a sua disseminação pelo vento.
Njivski osat (znanstveno ime Cirsium arvense) je trajnica iz družine nebinovk.
Njivski osat zraste do 150 cm visoko, steblo rastline pa je razraščeno. Na vrhu vsakega gladkega stebla so številni majhni svetlovijolični cvetni koški, ki v premeru merijo od 1 do 2 cm. Ovojkovi trni na koških so komaj opazni. Rastlina ima cele in nazobčane liste z bodicami ob robu. Spodnji listi so dolgi od 15 do 20 cm in široki od 2 do 3 cm. Semena so dolga od 4 do 5 mm in so opremljena s puhastim zadnjim delom, da jih veter lažje raznaša[1][2].
Najpogosteje raste na obdelanih površinah, najdemo pa ga tudi na posekah in pašnikih.
Poznani sta dve podvrsti njivskega osata:
Njivski osat (znanstveno ime Cirsium arvense) je trajnica iz družine nebinovk.
Åkertistel (Cirsium arvense) (L.) Scop. är en art i familjen korgblommiga växter.
Det är en flerårig grågrön ört med små violetta blommor som blommar från juli till september. Åkertistel anses vara ett mycket besvärligt rotogräs i större delen av Sverige. Lättbekämpad med kemiska växtskyddsmedel, men på frammarsch inom ekologisk odling.[1]
Dess biotop är kulturmark.
Wikimedia Commons har media som rör Åkertistel.
Åkertistel (Cirsium arvense) (L.) Scop. är en art i familjen korgblommiga växter.
Det är en flerårig grågrön ört med små violetta blommor som blommar från juli till september. Åkertistel anses vara ett mycket besvärligt rotogräs i större delen av Sverige. Lättbekämpad med kemiska växtskyddsmedel, men på frammarsch inom ekologisk odling.
Dess biotop är kulturmark.
Köygöçerten (Cirsium arvense), papatyagiller (Asteraceae) familyasına ait Avrupa ve kuzey Asya'da yaşayan bir bitki türü. Çok hızlı çoğalır ve zararlı ot olarak kabul edilir.
Alt türler:
Yakma yöntemi de denilen alevlemeye dayanıklı yabancı ot türleri arasında yer alır[1].
İki çenekliler ile ilgili bu madde bir taslaktır. Madde içeriğini geliştirerek Vikipedi'ye katkıda bulunabilirsiniz. Köygöçerten (Cirsium arvense), papatyagiller (Asteraceae) familyasına ait Avrupa ve kuzey Asya'da yaşayan bir bitki türü. Çok hızlı çoğalır ve zararlı ot olarak kabul edilir.
Alt türler:
Cirsium arvense subsp. arvense Cirsium arvense subsp. vestitumЛистки утворюють прикореневу розетку, з якої потім виростає стебло висотою від 30 до 200 см; у верхній частині стебло розгалужується.
Рослина звичайно дводомна, добре розмножується вегетативним шляхом. Буває, що утворює колонії тільки з осіб однієї статі. Тоді рослина цвіте, але насіння не дає. Час цвітіння — з червня по жовтень.
Осот польовий за рахунок вегетативного розмноження може заполонити все поле, витіснивши культурні рослини. У природі також зустрічається на луках, у заростях чагарників, вздовж доріг в низовинах та в горах.
Сильний стрижневий корінь може проникати на 2—3 метра, інколи зустрічаються корені довжиною 5—6 метрів. Приблизно на глибину 35 см від головного кореня паралельно поверхні відходять бульбоподібні потовщені корені, що запасають поживні речовини.
Осот польовий — хороший медонос.
Є дані про використання рослин у народній медицині.
Це незавершена стаття про Айстрові.Kế đồng hoặc Cỏ kế đồng (danh pháp khoa học: Cirsium arvense) là một loài thực vật thuộc chi Cirsium trong họ Cúc (Asteraceae), bản địa khắp châu Âu và phía Bắc châu Á, và được du nhập rộng rãi ở những nơi khác. Nó là một loại cây thân thảo lâu năm có chiều cao 30–100 cm, tạo thành các cụm sinh sản vô tính rộng lớn từ một hệ thống rễ ngầm dày dặc và trồi lên rất nhiều thân mọc thẳng khỏi mặt đất vào mỗi mùa xuân, đạt 1-1,2 m chiều cao (đôi khi cao hơn).[1] Nó là loài cây mọc nơi đổ nát.[2]
Cỏ kế đồng là thực vật lâu năm, có nằm trong danh sách 33 loài cỏ độc hại ở Bắc Mỹ và được biết là gây hại cho hơn 27 loại cây trồng ở 37 quốc gia, gây giảm năng suất đối với nhiều loại cây trồng, đồng cỏ, bãi cỏ, vườn nho và vườn cây ăn quả.[3]
Cấu trúc ngầm của nó bao gồm 4 kiểu:
Dù được xác nhận trong một số tài liệu nhưng thực tế thì kế đồng không tạo ra các thân rễ.[5] Các chồi rễ mọc ngẫu nhiên trên các rễ dày dặc của kế đồng, và từ đây sinh ra các chồi cây mới. Chồi cây cũng mọc ra từ các chồi bên trên đoạn ngầm của các chồi thông thường, cụ thể khi các chồi bị cắt hay khi các đoạn thân cây bị vùi lấp.[5]
Thân cây có màu xanh mịn, phân cành tự do,[5] và nhẵn nhụi (không có túm lông hay phấn), chủ yếu không có cánh gai. Thân một phần nằm bò trên mặt đất vào mùa hè, nhưng có thể mọc đứng lên nếu được hỗ trợ bởi thực vật khác. Những chiếc lá có gai nhọn, xẻ thùy, dài 15–20 cm và rộng 2–3 cm (nhỏ hơn ở phần trên của thân cây hoa).
Cụm hoa có đường kính 10–22 mm (0,39–0,87 in), màu hồng tím, với tất cả các chiếc hoa có hình dạng tương tự (không phân chia thành chiếc hoa đĩa và chiếc hoa tia). Những bông hoa thường là đơn tính khác gốc (cây đực và cây cái), nhưng không phải lúc nào cũng như vậy, với một số là cây lưỡng tính.[5] Hạt dài 4–5 mm, với một mào lông hỗ trợ trong việc phát tán nhờ gió[6][7][8]. Mỗi cành ra 1-5 cụm hoa đầu, với các cây trong điều kiện rất thích hợp sinh ra tới 100 cụm hoa đầu trên mỗi thân cây.[1] Mỗi cụm hoa đầu chứa trung bình khoảng 100 chiếc hoa. Lượng hạt trung bình mỗi cây là khoảng 1.530. Do hoa chủ yếu thụ phấn nhờ côn trùng nên khi các cây đực và cây cái mọc sát nhau thì số lượng hạt sẽ nhiều hơn.[1]
Các hạt của Cirsium arvense là nguồn thức ăn quan trọng cho sẻ thông vàng châu Âu và sẻ thông thông thường, và ở một mức độ thấp hơn là của các loài sẻ thông khác[9]. Lá của nó là thức ăn của hơn 20 loài bướm Lepidoptera, bao gồm bướm Vanessa cardui và Ectropis crepuscularia, và một số loài rệp vừng (Aphidoidea)[10][11][12].
Sự biến thiên trong các đặc trưng lá (kết cấu, lớp lông, sự chia đoạn, tình trạng gai góc) là cơ sở để xác định các thứ/chủng kế đồng.[1] Theo Flora of Northwest Europe[6] thì có 2 thứ là:
Theo Biology of Canadian Weeds: Cirsium arvense thì có 4 thứ:[1]
Giống như các loài Cirsium khác, rễ kế đồng ăn được nhưng hiếm khi được sử dụng do xu hướng gây ra đầy hơi ở một số người. Rễ cái được coi là phần nhiều dưỡng chất nhất. Lá cũng ăn được, nhưng do nhiều gai nên việc dùng nó làm thức ăn là không đáng giá. Tuy nhiên phần thân là ăn được và dễ dàng tách bỏ gai hơn.[13] Nhà máy rượu Bruichladdich trên đảo Islay liệt kê kế đồng là một trong số 22 thảo mộc sử dụng trong loại rượu gin của họ là The Botanist.[14]
Mào lông cũng được người Cherokee sử dụng trang trí cho các phi tiêu thổi bằng ống xì đồng của họ.[15]
Kế đồng hoặc Cỏ kế đồng (danh pháp khoa học: Cirsium arvense) là một loài thực vật thuộc chi Cirsium trong họ Cúc (Asteraceae), bản địa khắp châu Âu và phía Bắc châu Á, và được du nhập rộng rãi ở những nơi khác. Nó là một loại cây thân thảo lâu năm có chiều cao 30–100 cm, tạo thành các cụm sinh sản vô tính rộng lớn từ một hệ thống rễ ngầm dày dặc và trồi lên rất nhiều thân mọc thẳng khỏi mặt đất vào mỗi mùa xuân, đạt 1-1,2 m chiều cao (đôi khi cao hơn). Nó là loài cây mọc nơi đổ nát.
Cỏ kế đồng là thực vật lâu năm, có nằm trong danh sách 33 loài cỏ độc hại ở Bắc Mỹ và được biết là gây hại cho hơn 27 loại cây trồng ở 37 quốc gia, gây giảm năng suất đối với nhiều loại cây trồng, đồng cỏ, bãi cỏ, vườn nho và vườn cây ăn quả.
Растение — хороший медонос.
Раньше пучки «пуха» и отцветающие растения использовались в качестве материала для набивки чучел животных.
Есть данные о применении растения в народной медицине.
Сложный в таксономическом отношении и полиморфный вид; по мнению большинства современных систематиков, — фактически подрод из нескольких корнеотпрысковых двудомных видов. Согласно упрощенному пониманию границ вида, существуют разновидности:
Изредка встречаются особи с чисто-белыми соцветиями.
絲路薊（学名：Cirsium arvense），又名田薊[1][2][3]或加拿大薊[4]，是一種分佈在歐洲及亞洲北部的薊屬，並且廣泛引進到其他地方。雖然在北美洲一般稱它為加拿大薊，但是並非來自加拿大。[5]
絲路薊是高的草本多年生植物，從地下的根系統形成大型的克隆群落，並於每年春天長出1-1.2米高的莖。於夏天，莖很多是會部份躺下，若有其他植物支撐，則仍會保持挺直。葉子有很多尖刺，長15-20厘米及闊2-3厘米。花序的直徑長1-2.2厘米，所有小花的形狀相似。花朵一般都是雌雄異體的，但並非沒有不同，其中一些植株則會有雌雄同體的花朵。種子長4-5毫米，有冠毛，可以經風力傳播。[3][6][7]
絲路薊的種子是歐洲金翅雀及赤胸朱頂雀的重要食物，亦是其他雀科的食物之一。[8]絲路薊葉子是鱗翅目超過20個物種及一些蚜蟲的食物，當中包括小紅蛺蝶及埃尺蛾等。[9][10][11]
絲路薊一直被廣泛認為是一種野草，如在英國，它就被定為「有害的野草」。[12]它們在很多地區亦是嚴重入侵物種，一般是作為糧食種子的污染物而被引入這些地區。在很多國家，如澳洲、巴西、加拿大[13]、新西蘭及美國都將它定為有害的野草，一些國家甚至限制它們或其部份的引入。
絲路薊的根是可以吃的，以主根最有營養，不過卻有傾向令一些人放屁。葉子也是可以吃的，但清除尖刺卻令人感到厭煩。[14]
絲路薊（学名：Cirsium arvense），又名田薊或加拿大薊，是一種分佈在歐洲及亞洲北部的薊屬，並且廣泛引進到其他地方。雖然在北美洲一般稱它為加拿大薊，但是並非來自加拿大。
絲路薊下有兩個變種：
Cirsium arvense var. arvense：分佈在歐洲大部份地方。葉子下方沒有毛。 Cirsium arvense var. incanum：分佈在歐洲南部。葉子下方有厚毛。
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