Once autumn leaves have fallen, mistletoe becomes highly visible on large trees throughout Kentucky. Phoradendron, the scientific name for this parasitic plant, means tree thief. These small, leafy plants are commonly found on twigs and branches of many hardwood species in the southern United States. Mistletoes extract water, mineral elements and food from tree hosts; hence the name, tree thief.

Mistletoe use in holiday traditions has roots in pagan times. The appearance of a live parasitic plant while the host tree appears dead led some to believe mistletoe mysteriously held the life of the tree during winter. Druids harvested mistletoe in a special rite, never allowing the plant touch the ground, and then hung it in their homes for good luck.

Our modern-day mistletoe holiday tradition likely originates with a mythological Norse goddess of love and beauty. Frigga, whose son was restored from possible death by mistletoe, was thought to bestow a kiss on anyone walking beneath one. Today, when two people meet under the mistletoe, tradition suggests they must exchange a kiss for good luck.

Phoradendron, the most common mistletoe growing in Kentucky, resembles another species that grows in Europe. It has simple, fleshy green leaves arranged oppositely on the stem. Stems are short and more branched than host trees, so mistletoe often appears as a spherical bunch of dense vegetation. These bunches may be a foot or two in diameter and are located high in the tree where sun exposure is highest. Mistletoe berries range from white to straw-colored to light red. Birds eat the fruits, reportedly toxic to humans and animals, then deposit the seeds onto branches where they germinate and penetrate the next host tree.

Mistletoe commonly appear in open-grown trees where birds tend to roost and thereby, less frequently in forest trees. Generally, they cause minimal damage, although they can be harmful to stressed trees. Mistletoe can be removed from landscape trees by pruning.

For more information about tree parasites and diseases, contact the Bell County Cooperative Extension Service.

Stacy White is the Bell County extension agent for agriculture and natural resources. Educational programs of the University of Kentucky Cooperative Extension Service serve all people regardless of race, color, age, sex, religion, disability or national origin. Source: Nicole Gauthier, extension plant pathologist