American Holly (Ilex opaca)

The American holly is easy to identify since it is the only native U.S. holly that has spiny green leaves and bright red berries. Its leathery dark green leaves are also popularly used for home decoration during the wintertime. The tree's bright red berries ripen in October and remain on the tree throughout the winter. These berries are loved by birds. This tree also attracts insect pollinators and both small and large mammals.

Family: Aquifoliaceae (Holly)

Characteristics: The 1 ½-inch to 3 ½-inch-long leaves are leathery, dark green, and have widely spaced spiny teeth. In October, the tree's red berries begin to ripen and will remain on the tree throughout the winter. In May-June, green-white flowers begin to bloom. Male flowers occur in clusters of 3-12 flowers. Female flowers are solitary. Male and female flowers appear on separate trees. Bark is smooth and gray. This tree is dense and has a pyramidal shape. It grows 40-50 feet high and 18-40 feet wide.

Foliage: Evergreen (foliage present year round)

Geographic Origin: Eastern and Central United States (native)

Cultivation Notes: Requires low maintenance. Does best in full sun to part shade. This tree will lose foliage if exposed to too much shade. Prefers acidic, consistently moist, and well-drained soils. Poorly drained soils should be avoided. This is a slow growing tree.

Number on Campus: 1

Sources: Dirr, Morton Arboretum, Missouri Botanical Garden