Mistletoe is everywhere in Christmas imagery. When trees lose their leaves you can spot mistletoe easily. In Northern California we have American Mistletoe prolific in our oaks. The evergreen nature of mistletoe and the conifer trees used for ornaments; are symbols of life that doesn’t die back in the cold of winter; which brought hope that warmer and brighter times would return.
Mistletoe is a hemiparasite: it taps into the host tree for water and dissolved minerals, but it also produces some of its own nutrients through photosythesis, but does not kill the tree. In fact, research shows that mistletoe actually improves the health of the oak forests. Mistletoe provides a healthy carbon to nitrogen ratio that improves the soil and increases acorn production.
The story of how it gets in the trees is pretty funny - birds eat the sticky berries, and during digestion the sticky insides of the berry stick to the bird’s bum, so the bird needs to wipe onto the branches of trees to get them off. Then the mistletoe grows there. The word "mistel" "toe" literally translates to "dung on a twig".
Mistletoe acts as a keystone species in many areas. Experiments show that removing mistletoe can cut woodland bird diversity by more than a quarter because so many birds and insects rely on its leaves and berries for food and nesting.
Medicinally, most of the modern research focuses on European mistletoe (Viscum album), which is rich in lectins and viscotoxins; proteins that are both cytotoxic and immunomodulating and are being studied (and used in Europe) to treat cancer. Traditional Western herbalists have also used mistletoe in carefully prepared doses as a nervine and cardiotonic…supporting the heart, blood pressure, and seizures (while respecting that the plant contains potentially toxic constituents, especially in the berries, and must be worked with knowledgeably). In alchemy you will see an Ens of Mistletoe prepared (like pictured here).
So the plant we hang in doorways as a symbol of love and midwinter magic is, in the trees, a whole little ecosystem and in the apothecary a serious, nuanced medicine…and, a cute excuse for a holiday kiss.