December 2011
Featured Articles

Mistletoe

Plant with a Thieving Nature

Mistletoe is an interesting group of plants with an interesting history. On a worldwide basis, mistletoe may generically refer to any of more than 200 species of semi-parasitic shrubs. However, according to Curtis J. Hansen, Curator Freeman Herbarium at Auburn University, there is primarily only one species of mistletoe dominating the eastern United States and that is the "Oak Mistletoe," or, scientifically speaking, Phoradendron leucarpum. It sounds very romantic in Greek, but literally means "tree thief."

 

All mistletoes are parasitic, meaning they grow into a host tree and "steal" nutrients for growth. However, they are also green, so they can produce some of their own nutrients through photosynthesis. While most mistletoe don’t directly kill their tree-hosts, they can weaken the trees over time and the end result is still death. As the name indicates, Oak Mistletoe is mostly found in oak trees, but may also be found in other hardwoods. This particular species isn’t known to grow in pines or other conifers in our area. Mistletoes are particularly easy to spot at this time of year when the leaves of the hardwood trees have fallen. In fact, you may find many plants in full fruit with little white berries since female and male plants are in full flower. There are separate female and male mistletoe plants within this species.

The thieving nature of mistletoe is often duplicated by the men I see hovering around the sprigs at Christmas parties who are always ready to steal a kiss. 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 (again not unlike the aforementioned men).

In the South, tiny yellow flowers bloom on the evergreen mistletoe from fall into winter. The familiar white berries begin to form soon after pollination and resemble little packets of glue around tiny indigestible seeds. Although eating mistletoe berries may potentially be lethal for humans, birds seem to be immune to any toxicity.

The immunity of birds to mistletoe’s poisonous qualities is essential to the welfare of the plant. The dispersal and propagation of mistletoe is largely dependent on birds eating the berries, but not digesting the seeds. Studies suggest seeds are most likely to survive and grow if a bird deposits them on the same species of tree on which the parent plant lived.

The use of mistletoe as a romantic lure stems from England at least as early as the 1500s. A version of the tradition persists today in secular Christmas decorations.

Mistletoe has an interesting story behind its name. Several hundred years ago, it was thought 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 with the name mistletoe because "meet me under the dung-on-a-twig" just doesn’t set the right festive mood.

Tony A. Glover is a County Extension Coordinator in Cullman County.