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<li>This account reviews information on all aspects of the biology of <em>Cirsium dissectum</em> (L.) Hill that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the <em>Biological Flora of the British Isles</em>: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history and conservation.</li>
<li><em>Cirsium dissectum</em> (meadow thistle) is a perennial, rhizomatous herb found in moist, nutrient poor grasslands and heathlands in north-west Europe. It is readily distinguishable from other <em>Cirsium</em> species in the British Isles but has been considered a subspecies of <em>C. tuberosum,</em> along with <em>C. filipendulum,</em> in some other areas of Europe.</li>
<li>It is susceptible to being out-competed by species that are able to increase biomass more rapidly. At more productive sites, greater nutrient availability increases the proportion of rosettes that flower, as well as rosette turnover. Seeds germinate readily under a range of conditions in the growth room and greenhouse but seedlings are very rarely found in the field. An examination of its population dynamics reveals that clonal propagation is the dominant form of reproduction, with the low number of seedlings primarily caused by very low establishment rates in vegetation stands.</li>
<li><em>Cirsium dissectum</em> is relatively tolerant of drought and shade even though it is found in moist grasslands. At very low pH it suffers from ammonium and aluminium toxicity. As it has suffered habitat loss through drainage and succession, <em>C. dissectum</em> has declined in the British Isles and it is now endangered in Germany and the Netherlands.</li>
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