Folklore in the United Kingdom tells that blackberries should not be picked after Old Michaelmas Day (11 October) as the devil (or a Púca) has made them unfit to eat by stepping, spitting or fouling on them.[39] There is some value in this legend as autumn's wetter and cooler weather often allows the fruit to become infected by various molds such as Botryotinia which give the fruit an unpleasant look and may be toxic.[40] According to some traditions, a blackberry's deep purple color represents Christ's blood and the crown of thorns was made of brambles,[41][42] although other thorny plants, such as Crataegus (hawthorn) and Euphorbia milii (crown of thorns plant), have been proposed as the material for the crown.[43][44]