Kissing under the mistletoe, a popular American holiday tradition, is held by some to increase the possibility of marriage in the coming year. In North America this tradition became established in the 1880s. One of the most mystical and sacred plants of European folklore, mistletoe has long been a symbol of love, peace, and goodwill. Traditions involving this plant date back to ancient times. Mistletoe was widely used centuries before Christ in pagan rituals. The ancient Druids of Britain used mistletoe to celebrate the coming of winter. The plant was so sacred to the Druids that if two enemies met beneath a tree on which mistletoe was growing, they would stop their battle and call a temporary truce. Most of us know mistletoe as a sprig of small, leathery green leaves and white berries tied with a red ribbon. American mistletoe, Phoradendron leucarpum, is an evergreen shrub native to the United States. It’s generally found growing in the tops of hardwood trees in the eastern United States, from New Jersey to Florida and west to Texas and Illinois. Hardy to zone 6, it is found in Illinois’ southernmost counties. Other species of mistletoe, found in western North America, are parasitic on conifers. Most mistletoe sold during the holiday season is harvested in Oklahoma and Texas. Mistletoe’s scientific name, Phoradendron, means “thief of the tree” in Greek, and the name is apt: All mistletoe species grow as semiparasitic plants, living off the trees they attach themselves to. Mistletoe has specialized tissue (hasutorium) that grows into and combines with the tissue of the host plant. Although mistletoe’s green leaves supply some energy, the plant relies on its host for water and mineral. Dense evergreen mistletoe clusters are often found growing on such trees as oak, elm, and poplar. The bushy clumps are easily to spot in the fall and winter, when the host tree has shed its leaves. Mistletoe seeds are spread mainly by birds, which feed on the berries, digest their pulp, and excrete the living seeds. Even though mistletoe has only inconspicuous yellow or white flowers, so small as to be barely visible, it was adopted in 1893 as the official state floral emblem of Oklahoma — 14 years before Oklahoma became a state. Mistletoe appropriately represented the Oklahoma landscape and population: It is reported that mistletoe served to decorate settlers’ graves when no other flowers were available, and the evergreen plant was said to symbolize the perseverance of the state’s early settlers. Mistletoe is toxic and should not be ingested. The severity of toxicity varies, but it’s still wise to keep mistletoe out of reach of children and pets. For safety reasons, some companies have replaced the berries with artificial plastic ones.