Mistletoe

Tim Iverson

(12/2016) Many of holiday decorations adorn our homes throughout the early winter season. Few hold a place in our hearts like mistletoe. This charming plant that inspires romance is far more complex than most realize, however. Mistletoe is rooted deep within our culture, but it makes its home as a parasite deep within other living things. This toxic symbol of renewal has also helped as a medicinal plant throughout the ages. Mistletoe is an evergreen that is truly as versatile and complex as the mythos that surrounds it.

Like a true evergreen mistletoe leaves remain a bright and verdant shade of green throughout the year. Evergreens, as the name implies, are trees that remain green year round. They will keep their leaves or needles in almost all cases, all year, while deciduous trees will shed their leaves in the colder winter months. Evergreens are usually conifer trees, plants, or shrubs, and in some rare cases leafy trees.

Mistletoe is a widespread evergreen plant, with over 1,300 different species world wide and 30 making their home in North America. Remarkably, each and every species is considered a parasite. Safely nestled in the canopy away from the dangers below, mistletoes grow high in the crown of a tree. Mistletoe is generally spread by birds who eat the berries. The seeds, which are especially resilient and sticky, pass through the digestive system of the bird. Later when a bird excretes the seed it may stick to the branch where it is perched. If the seed is able to successfully stick, it will eventually germinate and grow roots into the branch of the tree. This allows the mistletoe to extract water, sugars, nutrients, and minerals from the tree itself. Not all mistletoes spread this way though. The Dwarf Mistletoe, native to western Canada and the United States, has berries that explode jettisoning the seeds out at 60 miles per hour and spraying them as far as 50 feet! By acting as a parasite and stealing valuable resources from its host, mistletoe harms the host tree and can kill it if the host tree becomes overcome with too many plants.

Despite the fact that mistletoe can be harmful to their hosts, they are extremely beneficial to other wildlife. They are classified as a keystone species, an organism that plays a crucial role in an ecosystem, and when removed have shown declines in abundance and diversity of life. Researchers in Australia and Mexico conducted experiments and found that in areas where mistletoe was removed from trees bird populations declined, whereas in control group areas where no mistletoe was removed bird populations stayed the same or increased. Chickadees, wrens, nuthatches, doves, owls, hawks, and squirrels are all commonly found to make nests within the roots and branches of mistletoe. In the US three different species of butterfly rely on mistletoe as their host plant. The Johnson Hairstreak, the Thicket Hairstreak, and the Great Purple Hairstreak species lay their eggs on the leaves, and when they hatch they will consume the leaves. The berries are a food source for birds and mammals alike during the autumn and winter months. However, they are toxic and not recommended for direct human consumption.

Eating the berries or drinking mistletoe tea isn’t uncommon, but consumption may cause side effects caused by phoratoxin, which is found throughout the plant with higher concentrations specifically in the leaves. Symptoms of mistletoe poisoning include weakness, drowsiness, blurred vision, diarrhea, nausea, vomiting, and seizures. Despite all this, mistletoe has medicinal properties. Historically it was used by Europeans to treat insomnia, infertility, headaches, hypertension, and arthritis. Case studies have shown that most accidental ingestions resulted in only a few severe reactions and zero fatalities. There are even clinical trials, being administered by the National Institutes of Health and Johns Hopkins’ School of Medicine, as a potential treatment for the side effects of chemotherapy. Infections of a mistletoe solution are available in Europe via prescription. Connections between mistletoe and health or cancer treatment are not well understood. This is due to the poor quality of the research. Until more thorough and definitive studies and understanding comes along it won’t be widely available, if at all. Considering its natural toxicity consumption is still unwise and ill-advised.

Historically speaking evergreens have been a part of the winter season for millennia. These plants were brought in and adorned the homes of many ancient peoples across cultures and continents. December 21st and 22nd typically has the fewest daylight hours of the year, and is marked as the winter solstice. Most ancient cultures worshipped the sun as a god, and this solstice symbolized the triumph of life over death as the days would begin to grow longer from this point forward. Evergreens were a symbol of health and virility, and reminded them that green plants would grow and farms and fields would once again produce food. Ancient Egyptians, Romans, Celtic druids, Vikings, and Germanic barbarians all had similar traditions.

It’s not exactly clear how, where, or when the mistletoe kissing tradition originated. One tale holds that the evergreen is a sign of fertility and many species have white berries that secrete a white substance. A Norse myth holds that the god Balder was killed by a mistletoe arrow and as a sign of peace people began to kiss under it. In the late 18th century England and America it was considered by many to be bad luck for a woman to refuse a man’s kiss under the mistletoe. A common theme was to give one kiss for every berry on the plant. The word mistletoe originates from the Anglo-Saxon words ‘Mistle,’ which means dung and ‘Tan,’ which means stick. It roughly translates to poop on a stick, which kind of takes the wind out of the romantic sails.

If you find yourself under this holiday favorite this season share a kiss and share some knowledge. This little evergreen is more than just poop on a stick, it’s home to many thousands of animals and while it adorns yours just be sure not to shoot any Norse gods or unwelcome advances to would be lovers.