December 20, 2022
Front page of my local newspaper this morning described a venerated symbol of Christmas as a tree killer. Sprigs of this vine hang from lentils, swing from lights and chandeliers, and hang above door passages. The first written reference comes from a 1820’s story by Washington Irving as the “kissmas-time” berries were “hung up to the imminent peril of all the pretty housemaids.” Mistletoe can grow year-round but it tends to bloom in the late fall and winter. The sprigs become more pronounced as the tree drops its leaves and the bright green leaves of the vine are visible. The article stated while this may brighten the yard, it is a warning sign for the tree and a “certified arborist” should be called for an assessment. If the tree can be saved, it will require removal of the mistletoe.
When I looked online, I found Mistletoe is the common name for obligate hemiparasitic plants in the order Santalales. All species in the order are attached to their host tree or shrub by a structure called the haustorium, which they use to extract water and nutrients from the host plant. While a parasite, the green leaves can use photosynthesis to produce their own food if necessary. Mistletoe originally referred to European mistletoe (Viscum album) which is the only species native to the British Isles and much of Europe. A related species (Viscum cruciatum) with red rather than white fruits, occurs in Southwest Spain and Southern Portugal, as well as in Morocco in North Africa and in southern Africa. The genus Viscum is not native to North America, but Viscum album was introduced to Northern California in 1900. The mistletoe of eastern North America (Phoradendron leucarpum) belongs to a distinct genus of the family Santalaceae. European mistletoe has smooth-edged, oval, evergreen leaves borne in pairs along the woody stem, and waxy, white berries that it bears in clusters of two to six. The eastern mistletoe of North America is similar, but has shorter, broader leaves and longer clusters of 10 or more berries. The term has been broadened over the centuries to include many other species of parasitic plants found in other parts of the world with similar habits that are classified in different genera and families.
Another warning about mistletoe is while it is a favorite food for many birds, it can be poisonous to humans. The 1500 species of mistletoe vary widely in human toxicity. European mistletoe is more toxic than American mistletoe yet concerns regarding toxicity are more prevalent in the US. The effects are not usually fatal and in parts of South Asia, mistletoe is frequently used as an external medicine. The active substances are Phoratoxin (in Phoradendron) and Tyramine (in Viscum) and their effects include blurred vision, diarrhea, nausea, and vomiting, and less commonly cause cardiac problems such as seizures, hypertension, and even cardiac arrest. The toxins are more concentrated in the leaves and berries of the plant, with teas prepared from the plant being particularly dangerous. While adults may suffer little effect, these symptoms are more pronounced in small children and in animals. Despite its toxicity, mistletoe has been used historically in medicine for its supposed value in treating arthritis, high blood pressure, epilepsy, and infertility. While mistletoe may illicit a kiss, eating or drinking the sprig is not advised.
THOUGHTS: I was introduced to mistletoe as a young child as a sprig was always hung over the arched divider between our living and dining rooms. I was too young to consider using the sprig, but since the mistletoe was hung over the large furnace floor grate I was often “under the mistletoe” to keep warm. The custom of kissing under the mistletoe was popular among servants in late 18th-century England, and one of the earliest references to mistletoe traditions in popular music is “I Saw Mommy Kissing Santa Claus” released by Jimmy Boyd in 1952. Sneaking a kiss with a loved one is not a bad tradition to keep. Act for all. Change is coming and it starts with you.