Viscum album Christianity became widespread in Europe after the 3rd century AD, the religious or mystical respect for the mistletoe plant was integrated to an extent into the new religion. In some way that is not presently understood, this may have led to the widespread custom of kissing under the mistletoe plant during the Christmas season. The earliest documented case of kissing under the mistletoe dates from 16th century England, a custom that was apparently very popular at that time. Winston Graham reports a Cornish tradition that mistletoe was originally a fine tree from which the wood of the Cross was made,
Viscum nudum"), but with the plant drawing its mineral and water needs from the host tree. Different species of "Viscum" tend to use different host species; most species are able to use several different host species. The flowers are inconspicuous, greenish-yellow, diameter. The fruit is a berry, white, yellow, orange, or red when mature, containing one or more seeds embedded in very sticky juice; the seeds are dispersed when birds (notably the mistle thrush) eat the fruit, and remove the sticky seeds from the bill by wiping them on tree branches where they can germinate. "Viscum" species are poisonous to humans;