Mistletoe is the Englishcommon name for most obligate hemiparasitic plants in the order Santalales. They are attached to their host tree or shrub by a structure called the haustorium, through which they extract water and nutrients from the host plant . Their parasitic lifestyle have lead to some dramatic changes in their metabolism.
The name mistletoe originally referred to the species Viscum album (European mistletoe, of the family Santalaceae in the order Santalales); it is the only species native to Great Britain and much of Europe . A separate species, Viscum cruciatum, occurs in Southwest Spain and Southern Portugal , as well as Morocco (North Africa ).
Over the centuries, the term has been broadened to include many other species of parasitic plants with similar habits, found in other parts of the world , that are classified in different genera and even families—such as the Misodendraceae and the Loranthaceae.
In particular, the Eastern mistletoe native to North America , Phoradendron leucarpum, belongs to a distinct genus of the Santalaceae family . The genus Viscum is not native to North America , but Viscum album has been introduced to California . European mistletoe has smooth-edged, oval , evergreen leaves borne in pairs along the woody stem, and waxy, white berries that it bears in clusters of two to six. The Eastern mistletoe of North America is similar, but has shorter, broader leaves and longer clusters of 10 or more berries .