Mistletoe by Madeline Sullivin
Mistletoe is the common name for obligate hemi-parasitic plants in several families in the order Santalales. These plants grow attached to the branches of a tree or shrub by a structure called the haustorium. Through this structure, they absorb nutrients from the host plant.
European mistletoe is easily recognized by its smooth-edged oval evergreen leaves seen in pairs along a woody stem with waxy white berries in dense clusters of 2 to 6. In America, while the genus Viscum does not grow wild, the eastern mistletoe is similar, but has shorter, broader leaves and longer clusters of 10 or more berries.
Mistletoe is a poisonous plant. However, both European mistletoe and the North American species are commercially harvested for Christmas decorations. When Christianity became widespread in Europe after the 3rd century AD, religious or mystical respect for the mistletoe plant was integrated to an extent into the new religion. In a 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 this custom, which apparently became very popular at the time, dates from 16th century England. According to custom, the mistletoe must not touch the ground between its cutting and its removal as the last of Christmas greens at Candlemas (the ancient Christian festival of lights on February 2); it may remain hanging through the year, however, to preserve the house from lighting or fire until replaced the following Christmas Eve.
The American author, Washington Irving, in 1820, said “The mistletoe is still hung up in farm-houses and kitchens at Christmas, and the young men have the privilege of kissing the girls under it, plucking each time a berry from the bush. When the berries are all plucked the privilege ceases.”
Oklahoma uses mistletoe as its state floral emblem, and until 2004 the plant was presumed to be the official state flower. In 2004, though, the Oklahoma Rose was designated as such.
Mistletoe was often considered a pest that killed trees and devalued natural habitats. However, it has recently been recognized as an ecological keystone species, which is an organism that has a disproportionately pervasive influence over its community. A broad array of animals depends on mistletoe for food, consuming the leaves and young shoots, transferring pollen between plants, and dispersing the sticky seeds.
In western North America, the juicy berries are eaten and spread by birds. When eaten, some seeds pass unharmed through their digestive systems, and if the birds’ droppings happen to land on a suitable branch, the seeds may stick long enough to germinate. This manner of propagation is reflected in its name–mistel is the Anglo-Saxon word for dung, and tan is the word for twig; it becomes dung-on-a-twig. Another popular name is “witches’ brooms,” and the Navajo name for mistletoe is “basket on high.”
A study of mistletoe in junipers concluded that more juniper berries sprout in stands where mistletoe is present, as the mistletoe attracts berry-eating birds that also eat juniper berries. Such interactions lead to dramatic influences on diversity, as areas with greater mistletoe densities support higher diversities of animals. Rather than being a pest, mistletoe can have a positive effect on biodiversity, providing high quality food and habitat for a broad range of animals in forest and woodlands worldwide.