Your love life isn't the only thing mistletoe is good for; there are many animals that need it, and a possible surprise health benefit, too!
What exactly is Mistletoe?
Mistletoe is a seriously fascinating plant. There are over 1,300 species worldwide, 30 of which occur in North America and 20 or more that are endangered across the globe. To get a bit technical, mistletoe is an aerial flowering evergreen perennial, which means you will see it growing in trees rather than on the ground and throughout all four seasons. It's considered a hemiparasitic plant, because although it feeds off of the water and nutrients provided by a host tree or shrub, many species produce their own food through photosynthesis, making them only partially parasitic.
How does it parasitize trees and shrubs?
When a sticky mistletoe seed is either transported by an animal or deposited by a bird onto a limb, it waits for a good rain then gets busy producing a rootlike structure called a haustorium that penetrates the surface of its host. This structure is how it depletes or at least decreases the water and nutrients the host tree or shrub needs.
How can you spot mistletoe?
You can find at least one species in almost every state or province in North America. The best time to see it is in winter because, as mentioned, it is an evergreen and when leaves are absent, you can find these large masses more easily. You're looking for a large round ball of greenery attached to trees (see photo below). If you find these, then you are possibly in the presence of mistletoe! Mistletoe berries may be white as well as pink or red, so you aren't only looking for the all-too-familiar white ones. But remember, no matter what the color, don't snack on them, they may not be toxic to wildlife but are known to be quite toxic to humans.
Who benefits most from mistletoe?
Mistletoe isn't just for kissing (although that's a pretty fun way to use it!), it's a necessity for many mammals, birds, bees, butterflies and other insects as well. Mistletoe is the larval host plant (meaning eggs are laid on the leaves which feed the growing caterpillar) for at least one species of butterfly, the great purple hairstreak. Not only is this the food source for its caterpillars, but the toxicity from leaves passes on to the caterpillar and ultimately the adult and provides some protection from predators. Many other species of insects including one species of twig beetle, several thrips and mites also depend solely on mistletoe for their survival.
Mammals such as cattle, deer, elk, squirrels, chipmunks and porcupines rely on mistletoe leaves or berries, particularly when food sources are scarce in the fall and winter. Many of the smaller mammals also use the witches' broom for nesting and cover.
Numerous bird species benefit greatly from mistletoe because while the plant and its host are both alive, they feed on the sticky berries (this is also how the plant spreads) and use the large mass of vegetation, known as witches' brooms, for nesting sites and cover. To this point, researchers discovered that over 40 percent of spotted owl nests were associated with witches' brooms. Other birds known to use mistletoe for nesting include Cooper's hawks, chickadees, pygmy nuthatches, mourning doves and house wrens. Once the host tree dies, and the mistletoe along with it, many cavity nesting birds and small mammals move in, so the dead host tree creates high quality nesting habitat, which is a huge plus. According to the National Wildlife Federation, forests that have mistletoe may produce three times as many cavity nesting birds as forests lacking mistletoe.
What about people? Is there a benefit for humans other than exchanging kisses?
There certainly seems to be, and possibly an important one. According to Johns Hopkins and the National Cancer Institute, mistletoe is being tested in trials for use in numerous types of cancer treatment. According to Johns Hopkins, mistletoe injections are currently among the most widely used complementary cancer treatments in Europe. That's pretty amazing. One day we could be taking injections of mistletoe in lieu of chemotherapy. See? It is a very interesting plant and clearly not your average holiday greenery!
Happy holidays to everyone, now go kiss someone (with their consent, of course) under this epically cool aerial, hemiparasitic, potentially life-saving, evergreen perennial!