COLUMBIA, Mo. – Hanging mistletoe is a holiday tradition around the world. But have you ever wondered why we steal a kiss because we’re standing under some shrubbery?

“The use of mistletoe around the holidays dates back to pre-Christian times when it was used by Druids in rituals associated with the winter solstice,” said David Trinklein, horticulture specialist for University of Missouri Extension. “After being harvested by Druid priests with a golden sickle, people placed it over their door as a means of warding off evil in the coming year.”

Because of its wide use, it’s difficult to pinpoint where the Christmas kiss under the mistletoe began. It could be based on a Norse belief.

“A Norse legend says that mistletoe in the house would keep warring spouses from becoming too belligerent toward each other,” Trinklein said. That kiss-and-make-up could have translated, over the millennia, into a kiss under the mistletoe.

Or it could be based on a Scandinavian tradition that forced combatants to stop fighting. “Legend has it that when two enemies would meet under a tree that had mistletoe, they were duty-bound to lay down their weapons for a day,” Trinklein said.

Of course, not everyone was happy with the use of mistletoe. Because the plant was associated with pagan practices, early Christian churches banned its use. “Instead of mistletoe, the church encouraged their followers to use holly. That’s how holly became associated with Christmas,” Trinklein said.

Perhaps it’s the name that offends. In ancient times people observed that mistletoe appeared on branches where birds left their droppings. So the word mistletoe is derived from two Anglo-Saxon words, “mistel,” which means dung, and “tan,” which means twig, Trinklein said. So you’re actually stealing a kiss under dung-on-a-twig. How’s that for romance?

All fun aside, there is one very important warning. Mistletoe is poisonous. It contains viscotoxins, a mixture of toxic proteins found primarily in its leaves and stems. For that reason, real mistletoe should not be used to decorate homes in which there are small children or pets.

Today, most of the mistletoe sold for holiday decoration is artificial. Whether real or artificial, mistletoe still seems to cast its magical spell over those who stand under it.

SIDEBAR

• Each sprig of mistletoe offers a limited number of free kisses. Mistletoe lore says a berry should be plucked for every kiss. When the berries are gone, that’s an end to the twig’s kissing power.

• While toxic to humans, mistletoe is favored, when other foods are scarce, by birds such as robins, bluebirds and mourning doves.

• It is hemiparasitic, meaning it obtains some of its nourishment from its host but can also photosynthesize.

• The genus name for juniper mistletoe, Phoradendron, is derived from Greek and means “thief of the tree.” This name alludes to the parasitic habits of this mistletoe—it produces its own chlorophyll but steals water, minerals and other nutrients from its host.

• Viscum album, the European mistletoe, and Phoradendron serotinum, from North America, are the two mistletoe species most commonly harvested and sold during the Christmas holidays. While both are toxic, European mistletoe is much more toxic than the North American species.