American holly (Ilex opaca) is an evergreen shrub or small tree with a fairly dense narrow crown and short trunk. Leaves are oval, stiff, and curled. Old leaves can turn yellow and fall with flowers in the spring. Bark is smooth and gray. Flowers are tiny, greenish, and form on new growth between May and June. Fruits are red berries in small clusters. They are occasionally yellow. From the eastern and southern United States, mostly along the coast. The heyday of American holly culture was between the 1940s and 1960s. The name opaca means opaque or dull, referring to the leaf surface as contrasted to that of the English holly. This species is easily identified because it is the only native U.S. holly with spiny green leaves and bright red berries. The genus name comes from the Latin name Quercus ilex for “Holm Oak” in reference to the foliage similarity (leaves of holm oak are also leathery and evergreen). The specific epithet, opaca, meaning “opaque” or “dull” in reference to the non-lustrous leaf surfaces.
Common name: American Holly
Scientific Name (family and order): Ilex opaca Ait. (Aquifoliaceae, Aquifoliales)
Species Origin: Eastern United States.
New Jersey Status: USDA Native
Habit: 15’ -30’ high x 10 – 20’ wide; upright pyramidal to broadly conical.
Habitat: Zones 5 – 9. Sandy soil near the coasts and moist woods. Common in understory of open woods but plant loses foliage in excessive shade. Tolerates a broad range of soils but not moisture-saturated soil.
Trunk/Stem: Bark gray and smooth
Leaves: Evergreen, Simple, Alternate. Elliptical to oval; curled usually with several sharp spines; 4 “ long 2” wide; spiny at tip and margins (at most 7 – 8 per leaf side). Leaf spines less marked on those leaves higher up on the tree. Leaf blade is matte dark green above and pale-green below. Old leaves turn yellow and drop off.
Flowers: Dioecious; male staminate flowers in cymes in groups of 3 – 12; female flowers in clusters of 1 – 3 on a peduncle. The small dull-white flowers occur in leaf axils; flowers bloom in May – June (latest evergreen to flower). Four white sepals; four petals, four alternosepalous stamens; stamens sterile in female flower. Four carpels.
Fruits and seeds: Red berry-like with 4 pyrenes, borne singly on 1/4“ long pedicel, maturing in October. Fruit remains on plant during winter though it is a popular fruit for birds.