It’s Dec. 1 and many people’s thoughts are turning to holiday traditions. Christmas trees and other decorations are going up in homes, businesses, and cities across the state. Sprigs of mistletoe are scattered among those decorations, often above doorways in the hope of inspiring a holiday kiss.
American mistletoe (Phoradendron leucarpum) is the only species of mistletoe native to Kentucky. It is an evergreen shrub that grows in the tops of trees. It is considered hemi-parasitic which means it is partially parasitic. The mistletoe uses its evergreen leaves for photosynthesis and to produce its own food. However, it steals all of its water and minerals from the tree in which it is growing. Most non-parasitic plants use their roots to gather water and minerals from the soil.
When a mistletoe seed lands on a tree branch, it germinates and sends out shoots that penetrate the tree’s bark. Those shoots produce a chemical that tricks the tree into thinking that the mistletoe is a tree branch. The tree sends water and minerals to the mistletoe just like it would any other branch. The mistletoe can also cause the tree to send extra water and minerals to it, even at the expense of the rest of the tree.
According to the Plant Life of Kentucky (Jones 2005), American mistletoe blooms from Oct. to Dec. in this state. Mistletoe has male and female plants which means that some plants only have female flowers and some plants only have male flowers. The flowers are small and non-descript but are attractive to many species of wasps, bees, and ants. Honey bees as well as native bees will collect nectar and pollen from mistletoe flowers. The fertilized female flowers will produce white berries in the late fall and winter. The ripe berries are quickly eaten by a wide variety of birds.
Although mistletoe is poisonous to humans and some mammals, its leaves are the sole food for the caterpillar of the great purple hairstreak butterfly (Atlides halesus). The great purple hairstreak is common over much of its range, but relatively rare in Kentucky. Despite its name, the great purple hairstreak is more blue than purple. The adults will feed on a variety of flowers, but the green caterpillars only eat mistletoe vegetation.
Mistletoe has been documented on at least 30 species of trees in Kentucky. In addition to the variety of food sources mistletoe provides, its dense, shrubby growth pattern also provides cover and protection for nesting birds and treetop dwelling mammals. Mistletoe plays an important role in our Kentucky forest ecosystems as well as in our holiday traditions.
This article was part of Shannon’s original Kentucky Pollinators and Backyard Wildlife blog which evolved into the blog for Backyard Ecology. All of Shannon’s Kentucky Pollinators and Backyard Wildlife blogs can be found at https://shannontrimboli.com/posts/blog/.
Backyard Ecology: Creating Space for Pollinators and Wildlife
Nature isn’t just “out there.” It’s all around us, including right outside our doors. Hi, my name is Shannon Trimboli, and I am the host of Backyard Ecology. I live in southcentral Kentucky and am a wildlife biologist, educator, author, and owner of a nursery specializing in plants for pollinators and wildlife conservation. I started Backyard Ecology as a way to share my love of exploring nature and learning about different plants and animals. I invite you to join me as we ignite our curiosity and natural wonder, explore our yards and communities, and improve our local pollinator and wildlife habitat. Learn more or subscribe to my email list at www.backyardecology.net.