new year The decorations are ready: a cut tree, cheerful stockings on the mantel and… wait, what’s that white berry herb hanging from the ceiling? So why do people fall so in love when they find themselves under it?

MistletoeThe parasitic plant, a parasitic plant, is actually accustomed to suspension: In nature, it grows only on the branches of other trees. And it has long been associated with mystical power: in Norse legend, the god Balder is accidentally killed by a mistletoe arrow; thereafter the plant becomes synonymous with his grieving mother’s undying love. Although the berries of mistletoe are poisonous, ancient Romans and Greeks used its leaves medicinally to treat cramps, epilepsy, and ulcers. And first-century Celtic druids apparently used mistletoe to make a sacred fertility potion; this was a historical use that foreshadowed the plant’s now dominant identity as an excuse for kissing.

The first known reference to kissing under the plant dates from a 1784 English poem; In this poem, three men “kiss under the mistletoe” the lips of “a girl who is not yet twenty years old”. Until then, every woman or girl who passed under this vegetal decoration had to stop and wait to be kissed. One historian suggests that this tradition was coined by a “particularly lusty and imaginative” English boy, whose ruse spread first across the country and then around the world. As American author Washington Irving wrote around 1820, each berry on a mistletoe branch represented a kiss bestowed by a man on a young woman standing beneath the plant, and “the privilege ceases when all the berries have been gathered.” As for the girl on the other end, the (otherwise chaste) social customs of the time required that she never refuse a kiss under the mistletoe, lest she invite bad luck in the marriage market.

Today’s typical mistletoe decor differs from its 19th-century counterpart in several respects. Its fruits are not poisonous because the ingredients are usually fake; these fake berries are often mistakenly red instead of white; and the branches are (hopefully) no longer used to coerce reluctant recipients into kissing. Yet at family gatherings and cheesy movies, mistletoe remains the catalyst for many strange or amusing holiday pecks.