You can call it the emasculator of the old king, a sexual symbol, latent with fertility or a good luck charm for a dairy herd. It's been used as an antidote for poison, a fire suppressant, a protection against evil spirits, a pain reliever for rheumatoid arthritis and as a gift of peace between warring neighbours. This parasitic shrub with sticky white berries has somehow shrugged off its shady past to become a tradition of our Christmas. But this is, after all, a season of myth, legend, and make believe.

Today mistletoe, while not exactly decking our halls, is hung over doorways to entice a couple to exchange a kiss. And we have forgotten even the meaning of its name.

The name is perhaps derived from the ancient belief that mistletoe was propagated from bird droppings, a belief related to the then-accepted principle that life could spring spontaneously from dung. It was observed in ancient times that mistletoe would often appear on a branch or twig where birds had left droppings. "Mistel" is one of the Anglo-Saxon words for "dung," and "tan" is "twig". So, mistletoe means "dung-on-a-twig". Not a name that would normally encourage thoughts of romance.

Kissing under the mistletoe was practiced in the Greek festival of Saturnalia to bestow fertility and the dung from which the mistletoe was thought to arise was honoured for its life-giving power. From the earliest times mistletoe has been one of the most magical, mysterious, and sacred plants of European folklore.

Scandivanians enjoy kissing under the mistletoe. In earlier days they associated mistletoe with their goddess Freya and the part it played in the death of her son, Baldur the Beautiful. Once Baldur had a dream of his own death and, frantic in her anxiety, Freya asked all things, living and dead, not to harm him. She was given this promise by everything in the elements, but the mistletoe, a parasite, was no part of air or earth. Alas ! It was overlooked ! Loki the Trickster soon discovered this, and made an arrow from the little shrub. He tricked poor blind Bod into shooting the arrow at Baldur - with the inevitable result. The mistletoe grieved for its part in the tragedy, weeping until its red berries turned pale, and Freya forgave the plant with a kiss. Vikings used a branch to betoken peace.

Mistletoe is especially interesting botanically because it's a partial parasite. French tradition tells us that mistletoe is poisonous because it was growing on a tree that was used to make the cross of Jesus. Because of this, it was cursed and denied a place to live and grow on earth, doomed forever to be a parasite.

The mistletoe of the sacred oak was especially sacred to the ancient Celtic Druids. The ritual of cutting the mistletoe symbolised the emasculation of the old King by his successor. Mistletoe was long regarded as both a sexual symbol and the "soul" of the oak. It was gathered at both mid-summer and winter solstices, and the custom of using mistletoe to decorate houses at Christmas is a survival of this tradition.

In medieval times branches of mistletoe were hung from ceilings to ward off evil spirits and placed over house and stable doors to prevent the entrance of witches. Farmers would give the Christmas bunch of mistletoe to the first cow that calved in the New Year thus bringing good luck to the entire herd.

Mistletoe is also believed to lower blood pressure, improve circulation and relieve the pain of rheumatoid arthritis although these effects have not been scientifically validated. In some alternative medicine therapies, mistletoe is used as long-term therapy to prevent hardening of the arteries.

If you hang up mistletoe this Christmas, please follow the correct etiquette: a man should pluck a berry when he kisses a woman under the mistletoe, and when the last berry is gone, there should be no more kissing ! Remember that an unmarried woman not kissed under the branch will remain single for another year, and always burn the Christmas mistletoe on the twelfth night lest all the couples who kissed under it never marry.

Come, kiss me under the dung-on-a-twig and raise your glass to mistletoe and a Merry Christmas!