The American Holly (Ilex opaca) is one of six species of holly tree native to North America, but the only one found naturally on the Cumberland Plateau. The American Holly pictured with this article can be found on the west side of Webb Avenue next to the Flynn Sign Company. It is an excellent example of how this native tree can flourish in an urban environment.
American Holly is a distinctive tree and can be identified several ways. The American Holly has leathery, evergreen leaves, two to four inches long and one to two inches wide, with a sharply pointed tip and spiny-toothed margins. The leaves are alternate on the branches, rather than appearing opposite of each other. The fruit is a bright red berry, and the bark is thin, gray and often warty. An American Holly tree may grow up to 50 feet tall, with short branches forming a narrow, pyramidal crown.
American Holly trees are either male or female. The female trees will have the bright red berries, and the presence of these berries is a positive way to identify a female tree. Male trees lack berries, but a lack of berries does not positively mean the tree is male. The best way to identify a male American Holly is to look at the flowers in the spring. Males have staminate flowers and females have pistillate flowers. You should consult a botany book or website for pictures of these flowers. If you wish to have an American Holly that displays the bright red berries you must be able to make this gender identification, because you must plant both female trees and at least one male tree, no more than 100 feet away, to ensure pollination and fruit production.
American Holly makes a great addition to your landscape. Being evergreen, it adds color throughout the year. American Hollies grow best in well-drained, moist soil that is acidic, and in full or mostly full sun. They are cold-hardy and have few insect or disease problems.
Trees of Distinction are selected quarterly by the Crossville Tree Board, and articles about them are published in the Crossville Chronicle. This endeavor is to promote awareness of the importance of trees in our local environment.