Mistletoe the leaves and berries of the plant, with teas prepared from the plant being particularly dangerous. While adults may suffer little effect, these are more pronounced in small children and in animals. There are 1500 species of Mistletoe, varying widely in toxicity; the European Mistletoe ("Viscum Album") is more toxic than the American Mistletoe ("Phoradendron serotinum"), though concerns regarding toxicity are more prevalent in the US. Mistletoe has been used historically in medicine for its supposed value in treating arthritis, high blood pressure, epilepsy and infertility: Conversely, it can cause vasoconstriction and bradycardia, and is also used as an illegal
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;