The perennial Autumn Crocus (Colchicum autumnale), one of around a hundred species in the genus Colchicum, is is one of the most widespread species in the genus and the only one found as far north as northern Europe and Great Britain. Its distribution is limited to Europe, but within Europe it is very broadly (although not continuously) distributed. Autumn Crocuses are generally found in periodically wet to moderately moist grassland, but occur also in alluvial forests item 
The flowers and leaves of the Autumn Crocus appear at different times. Flowers appear in the fall and may be present into the winter; leaves appear in the spring and may be present into mid-summer. 
Autumn Crocus is perhaps best known as the source of the highly toxic alkaloid colchicine (colchicine has some limited medical applications, but must be used with great care). Although livestock generally avoid this plant, occasional poisoning occurs in cattle, horses, sheep, and pigs, sometimes leading to death. Colchicine has also long been used by plant breeders to generate mutations, a few of which may result in desirable traits, notably polyploidy. The late flowering time and attractive flowers make the Autumn Crocus a popular ornamental plant. 
Jung et al. (2011) provide a thorough review of the biology of the Autumn Crocus, including its taxonomy, morphology, geographic and ecological distribution, reproductive biology, ecology, and physiology. 
The Autumn Crocus is not threatened in the central portion of its distribution, although it is a species of concern in some countries at the periphery of its range. 
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