If you’ve ever gotten frisky with a loved one under the mistletoe, you were kissing under a parasite. (How’s that for permanently ruining a holiday tradition?) Yes, it’s true–mistletoe encompasses a number of parasitic plants in the order Santalales that grow on host trees and shrubs. (That’s not a joke….the name of the order is really Santa-lales.)
European mistletoe (Viscum album), native to Great Britain, and Eastern mistletoe (Phoradendron serotinum), native to eastern North America, are the most widely known mistletoe species. Both species have smooth-edged, evergreen leaves and white berries.
Most mistletoes are hemi-parasitic, which means they rely on their host primarily for water and mineral nutrients; their evergreen leaves are able to conduct photosynthesis on their own. Mistletoe can eventually kill its host plant (not very Christmasy), though they’re usually not so fierce, only limiting the host plant’s growth. European mistletoe can parasitize more than 200 trees and shrubs. At right is a photo of mistletoe that have parasitized an oak tree.
Before you become too depressed about the insidious nature of a holiday legend, you’ll appreciate knowing that mistletoe does have a good side—it supports highly diverse species of wildlife. Many animals and birds eat the leaves, shoots, berries and seeds, and in North America, spotted owls nest in its dense evergreen thickets.
Happy 2008 to you & yours!
Photo courtesy of the U.S.D.A. Forest Service.