Tree of the Week: American Holly (Ilex opaca)

The American holly (Ilex opaca) is an evergreen tree long associated with the American experience of Christmas. Before the days of mass manufacture and petroleum-based fascimile of everything under the sun, fresh-cut branches of the American holly were used for Christmas decorations. The dark green foliage and bright red berries enlivened the home during the sometimes dreary days surrounding the winter solstice. The tradition was widely practiced, to such a degree that the wild American holly population suffered from hack-jobs and over-use. Today, vestiges of this tradition remain with us. We see the caricatures of holly leaves and berries printed on wrapping paper, greeting cards, and gift tags, and we also have plastic replications of holly leaves and berries wired to wreaths and plastic trees. Incidentally, Christmas time is an excellent time of the year to plant your very own American holly tree in your lawn or on someone else's property, with the permission of the landowner of course.

Our tree of the week is pictured center. This American holly (Ilex opaca) hails from Bienville Parish. It was collected by Professor Ed Leuck's botany class in 1987.

This tall, slender tree grows in the middle of a clay slope. Over the past 30 years, the presence of the sidewalk necessitated the removal of all lower branches: the limbs needed to be removed so as to allow easy passage for pedestrians and golf-carts.

The simple leaves are richly green with edges that curl under, making it difficult to see the overall shape of the leaf. Interestingly, the curling of the leaf makes the trees deceptively friendly: the prickly leaf edges are hidden!

Leaves are light-green, almost white, underneath. Note how they alternate along the twig.

Leaves have an elliptical shape with prickly edges. The curled leaf appears to measure less than 3 inches in length.

Flipping the leaf over and pressing flat reveals a length closer to 3 full inches. We count four prickly points on the edges plus a pointed leaf tip.

There are a few berries (drupes) hidden among the leaves.

This is a specimen collected from the wilds of northern Louisiana. We aren't seeing a great number of fruits. For your own planting project, you might desire more seasonal ornamentation that can be found on nursery stock specimen. American holly has long been under cultivation, so you can find nursery-grown trees that are positively covered in these bright red fruits.

Also, American hollies are dioecious, which means you will need two plants, a male and a female, to produce these pretty red fruits, which are only found on female plantings.

These drupes measure 3/8 of an inch in length. They are egg-shaped.

American holly fruits are larger than fruits of the yaupon holly (Ilex vomitoria).

These yaupon fruits are an eighth of an inch shorter in length. Yaupon fruits also have a spherical shape, compared with the egg-shaped American holly fruits.

LEFT: American holly (Ilex opaca); RIGHT: Yaupon holly (Ilex vomitoria)

You can find more information about the arboretum's American holly trees here and here.