Whether your interest is parasitic plants, ethnobotany or herbal medicine, the study and culture of mistletoe can quickly become intriguing diversions. There are more than 200 genera of mistletoe, spread over six continents.
You will find lush mistletoes with flamboyant scarlet flowers growing in the tropics, to be contrasted with unassuming dwarf mistletoes that make themselves at home in Northern conifer forests. And then there are the mistletoes that grow literally in our own Los Angeles back yards.
Mistletoe is a parasitic plant. This means that its entire life force is extracted from another botanical species. Mistletoe is typically found on the branches of trees. There are two types of mistletoe in our area.
One type can be found on ash, alder, birch, box elder, poplar, locust, silver maple and ash trees, while the other occurs exclusively on oaks. The first type is readily identifiable during this time of year since its host trees – all deciduous – have lost a great many of their leaves by now, slowly revealing the evergreen parasitic mistletoes that had been obscured by their hosts’ foliage.
These mistletoes are regularly encountered in the Santa Clarita Valley, visible as clusters of yellow-green growth – at maturity reaching three feet in height and girth – high up in the canopies of the trees in question.
The etymology of the word “mistletoe” is an appropriate place to begin learning about its life-cycle. “Mistel” is the Anglo-Saxon word for “dung” and “tan” (or “toe”) is the equivalent of “twig.” Thus, “mistletoe” means “dung-on-a-twig,” an accurate assessment by the inhabitants of ancient England as to how the seeds of this plant are dispersed. It was observed that where birds left their droppings, mistletoe grew. Actually, people at that time thought this was the result of so-called spontaneous generation, that dung miraculously gave birth to plants. Only later was it learned that seeds passing through the gut of birds are primed for germination by the digestive process, the acid in the bird’s stomach helping to break down the exterior coatings of the seeds.
Mistletoe is one of that small group of plants which have distinctly male (pollen producing) and female (fruit and seed producing) representatives. The female mistletoes local to our area yield small white berries. Birds such as thrushes, robins, cedar waxwings, back caps and titmice either swallow the berries and excrete their seeds or consume the berry pulp alone, wiping the sticky, leftover seeds onto branches. In either case, roots grow from the seeds through the tree’s bark. These roots develop structures known as haustoria, which anchor themselves into the water and mineral conducting vessels of the tree.
Mistletoe infestation can become so severe as to threaten the life of a tree. Florel, a product by Monterey Chemicals, is a contact spray that kills the green portions of mistletoe but must be reapplied since regrowth of the plant occurs annually. In extreme cases, remove mistletoe and cover infested branches with black plastic; regrowth from embedded roots/haustoria will not occur where light is excluded since mistletoe, like every other green plant, experiences growth as the result of photosynthesis.
Mistletoe is mentioned in Druid, Gallic and Scandinavian mythology. During the Middle Ages, it was used as an aphrodisiac and also to combat infertility, nervous disorders, high blood pressure, and vertigo. Rudolf Steiner, the founder of biodynamic agriculture in the early 1900s, played a leading role in bringing mistletoe to the attention of the general public as a medicinal plant. Today, mistletoe is widely used in many European countries in alternative cancer therapies.
A compelling case can be made for careful investigation of mistletoe’s anti-diabetic properties. African mistletoe has long been used to treat diabetes in Nigeria. In rats with diabetes, mistletoe has been shown to reduce blood glucose levels. Another study demonstrated that mistletoe extract stimulated insulin secretion from clonal pancreatic cells.
TIP OF THE WEEK: According to Dr. Gianfranco Grazi (at usa.weleda.com) “it is easy to cultivate mistletoe. Take a fresh, ripe berry and press it on the branch where it is supposed to grow. The sticky seed sticks to the bark and one can throw the berry skin away. No incision or other treatment is necessary. Dry weather and sunny days in March/April dry the seed, and it begins to germinate. It takes at least five to six years for a bush to reach one foot in diameter.”
Photo credit: neilalderney123 / Foter.com / CC BY-NC