I used to get so embarrassed when my much older cousin teased me about getting kissed under the mistletoe during Christmas. Turns out that this romantic plant is parasitic, poisonous and has a not-so-romantic origin in its name.

The use of mistletoe to get a kiss, stems from England at least as early as the 1500’s. In 1520, William Irving wrote that a young man should pluck a berry each time he kisses a young girl beneath the mistletoe. When all the berries are plucked off the mistletoe, it no longer has romantic powers. A version of the tradition persists today in Christmas decorations, but we don’t worry about the berries. As a matter of fact it may be best to make sure the berries are not present because of their toxic qualities.

The name Mistletoe refers to any of more than 200 species of semi-parasitic shrubs found worldwide. Mistletoe is common throughout the southern United States, and on every continent except Antarctica.

Mistletoe has a curious story behind its name. Several hundred years ago, it was thought that the mistletoe plant was formed spontaneously from bird droppings. Of course no one thought to look inside the bird droppings for a concealed seed. However, due to this error, the plant was given the name mistletoe which translates literally in English to “dung-on-a-twig.” I think we should stick to the name mistletoe because “meet me under the dung-on-a-twig” doesn’t set the right mood for a kiss.

Mistletoe’s distinctive green leaves, stems, and white berries–each with a sticky seed inside–are easily recognizable. As a small seedling, it roots into the bark and wood of a tree and makes a connection with the growing ring of the host. Although mistletoe makes its own food, it steals water and nutrients from its host tree.

Rather than true roots, the plant has extensions called “holdfasts” that grip the host plant. With the holdfasts the plants take what they want from the host plant.

Normally the effort to obtain water and minerals, or even space itself, is intense and highly competitive among most plants, but mistletoe does not encounter such problems. Tree limbs, a ready source of water and minerals for this unusual little plant, are available on every tree branch.

Unlike poinsettias, mistletoe is poisonous. The U.S. poison control centers reports accidental poisoning of children or pets with mistletoe each year. Swallowing American mistletoe can cause symptoms such as gastrointestinal upset but is not likely to cause serious poisoning if small amounts are unintentionally swallowed. With that in mind, it would be wise to keep Mistletoe out of the reach of children and pets.

Because of its parasitic nature, mistletoe can weaken or kill the trees it infests, especially if the tree has been compromised by pests, storms, or old age. Removing mistletoe may help revive the tree.

Mistletoe can be cut out of the tree. Remove all the roots by pruning the infested branch at least six inches below the spot where the mistletoe is attached. Unfortunately, pruning can damage the tree’s structure, making the cure worse than the problem. Be sure to take safety precautions when cutting branches out of trees, including wearing head and eye protection. After handling mistletoe plants, wash your hands thoroughly hot, soapy water.