It’s OK to smooch under the mistletoe. Just don’t eat it.

Kissing under the mistletoe may be a holiday tradition – its seasonal significance goes back centuries and spans several continents – but University of Georgia tree experts warn that the plant can make you dangerously sick.

The green plant with white berries is particularly tempting to pets and small children, said Kim Coder, a professor of tree health care with UGA’s Warnell School of Forestry and Natural Resources. Ingesting it, he said, can result in “great digestive problems.”

“It’s not something you should nibble,” Coder explained. “It doesn’t even taste good.”

The physical ramifications of eating the pretty but sickening plant depend on the person. Coder said some fortunate mistletoe eaters feel no ill effects at all from ingesting the bitter, waxy plant, but it’s far more common to suffer from “tremendous tummy ache.” Some are even unluckier: They can suffer seizures, and if they’re allergic to the plant, it can even prove to be fatal.

The holiday staple harms not just humans and pets. Mistletoe is incredibly damaging to trees, Coder said. Unlike Spanish moss, which grows on tree surfaces without damaging it, mistletoe “is a true parasite,” Coder said. “It works its way in, and the tree grows around it, causing structural and biological problems.”

It takes water from the tree, which can be quite damaging during a drought, Coder said. “You’d remove a parasitic tick from your pet, so you should remove mistletoe from your trees,” he added. “This is the time of year to say ‘no’ to helping mistletoe and ‘yes’ to helping your trees.”

If left unchecked, this parasitic plant “will cause stress and death to your tree,” Coder said.

There are hundreds of varieties of mistletoe that grow over a wide range of trees all over the Western Hemisphere. Just one species is found in Georgia, unlike the myriad varieties found as you head west into Texas and beyond.

American mistletoe has big leaves about the size of your thumb and small white berries. Coder said that when pressed between your fingers, mistletoe berries have a sticky, glue-like substance inside with little strings attached to its seeds.

That glue-like substance allows seeds to stick to other surfaces, spreading the plant. Birds often transport mistletoe to other, uninfected trees, Coder said.

Do your tree a favor and clean off the mistletoe before it’s too late. Seek the help of a certified arborist.

(Sandi Martin is a public relations coordinator for the University of Georgia Warnell School of Forestry and Natural Resources.)