The familiar white-berried Christmas mistletoe is just one of many hundreds of mistletoe species worldwide. All are plant parasites, and in their native lands many have similar folklore and superstitions to our own species. Most grow in the tropics and subtropics, with only a few species in northern temperate zones.
All mistletoe species grow as parasites on the branches of trees and shrubs. They rely on their hosts for water and mineral nutrient supply. Technically speaking they are only hemi-parasites as most have green leaves and can photosynthesise - but many do use some metabolites from the host.
There are a tremendous numbers of mistletoe traditions and legends - so these pages will only cover a few aspects...
The most obvious tradition is the kissing one. Hanging mistletoe and kissing loved ones, or complete strangers, below it is hugely popular Christmas custom.
It is probably a remnant of an ancient fertility tradition, helped along by some British re- invention in the 18th and 19th centuries. The European mistletoe, as a parasitic plant growing on deciduous trees, can be seen as a symbol of the continuing 'life-force' (and vitality/fertility) of the tree through the winter.