A surprise, mischievous smooch under the mistletoe is a December tradition steeped in folklore. Many historians believe that pre-Christian Europeans believed the plant possessed powers as an aphrodisiac, fertility stimulant, and poison eradicator, to name just a few. Our contemporary adaptation of this yuletide custom is far more innocent but still retains the spirit of romance.
Ironically, while mistletoe is synonymous with affection, it is far less hospitable to many tree species.
Mistletoe is the common name for several families of parasitic plant species that grow on the branches of trees by root-like structures which bore under the plant’s bark. These “roots” extract nutrients and moisture from the host plant; over time, the host plant will develop deformed or discolored growth, called witches’ brooms.
Infected trees decline from the top down and may die prematurely. Damage can, in some cases, be reversed with proper pruning maintenance. Details can be found in this Colorado State University fact sheet.
In Colorado, five western North American species of dwarf mistletoes (Arceuthobium species) infect conifers. Common host trees include lodgepole, limber, pinyon, and ponderosa pines.
Unlike the decorative European mistletoe (Viscum album), that has woody stems, white berries, and smooth leaves, dwarf mistletoes are small, leafless, yellow-ish plants with inconspicuous berries.
Mistletoes in Colorado Conifers. Colorado State University Extension, Fact Sheet 2.925
Dwarf Mistletoe: Parasitic Plants. Colorado State Forestry Service
Linda McDonnell, Denver County Master Gardener