In a series on the festive folklore of three iconic winter plants, Trevor Dines reveals why we hang mistletoe from ceilings and door frames in order to kiss under it during the festive period

There can be few plants more deeply immersed in tangle of ancient folklore and mythology than mistletoe. And few plants carry elements of this mythology with them so strongly to the present day, with millions of people kissing under the mistletoe – either real or plastic – at Christmas.

The origins of the folklore are not difficult to see. On a late winter’s day and lit by the setting sun, bunches of green mistletoe laden with white berries, with no visible roots and springing full of vigour from the branches of the naked trees, clearly come from another world.

They became powerful symbols of the continuity of life – fertility in a landscape that was otherwise dead. Filled with this magic, mistletoe could achieve extraordinary feats, bringing the deceased back to life, curing terminal illness, revealing the location of buried treasure and keeping witches away.

And with their milk-white berries, their link to fertility was inevitable. Locally, all sorts of intricate and complicated rites evolved to ensure the fertility of crops and livestock through the year. These usually involved burning year-old bunches or boughs of mistletoe entwined with hawthorn, known as bushes, at New Year, replacing them with fresh ones for the coming year.

In one case, the burning bush had to be carried over the first twelve ridges of the first-sown field, and it was a dark omen if the fire went out before this was achieved. Almost ubiquitously, such rites were followed with drunken revelry and, inevitably, much kissing.

The white, sticky-pulped fruit of our native mistletoe is not attractive to many birds, which preferentially forage for red, orange, blue or black berries instead.

They’re only really eaten by thrushes such as redwings, fieldfares and, of course, mistle thrushes, whose scientific name Turdus viscivorus hints at their fondness for the berries.

As with holly, pairs of mistle thrushes will often set up a territory around individual trees and defend their stock of berries. But mistle thrushes are not actually very efficient at distributing mistletoe seeds. They eat the berries whole, defecating a sticky mix of pulp and seed half an hour later, when the birds are likely to have moved on.

Much more efficient are blackcaps. These little birds eat the skin and pulp of the berry, but discard the sticky seed first, wiping it off their beaks against the bark of the tree. This is perfect for the mistletoe, as the seed is placed firmly against the branch ready for germination.

Interestingly, in recent years we’ve seen many more blackcaps migrating to Britain over winter, and this could be beneficial for mistletoe.

There is evidence that mistletoe is increasing in some areas and some of this could be down to blackcap activity, although this is likely to be a combination of factors, including better protection of the ancient apple orchards that are the most important habitat for mistletoe.

Only a handful of other species use mistletoe as a food plant – perhaps not surprisingly given that it’s such a tough plant packed full of toxic alkaloids.

Eight species of invertebrate feed on mistletoe, six of them being found only on this species.

They include several bugs and weevils, but the most famous associate is the mistletoe marble moth. This little moth, with wings mottled in white, brown and cobalt blue, is restricted to a few counties in south-west England and Wales where mistletoe is most frequent. Although beautiful, its colouring is highly effective camouflage, rendering it identical in appearance to a bird dropping.

Find out more about mistletoe on Plantlife’s website.

If you enjoyed this, then find out more about the folklore, superstition and facts surrounding the other festive plants holly and ivy.

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