Ilex opaca Aiton
Family: Aquifoliaceae
American Holly
Ilex opaca image

Tree to 15 m tall, trunk to 0.6 m in diameter

Leaves: alternate, evergreen, dark to dull green above, yellowish green beneath, 5 - 10 cm long, oval to narrow elliptic, few spiny teeth, thick and leather-like.

Flowers: either male or female, found on separate plants (dioecious), borne near leaf axils, white, usually four-petaled, male flowers in clusters of three to twelve, female flowers solitary or in groups of two or three.

Fruit: fleshy with hard nutlets in the center (drupe), bright red, rarely orange or yellow, 7 - 10 mm in diameter, spherical to egg-shaped.

Bark: light gray, wart-like.

Twigs: covered with reddish brown hairs when young, becoming pale brown and smooth.

Buds: 3 - 8 mm long with a pointed or rounded tip.

Form: pyramidal, becoming irregular with age.

Similar species: Ilex opaca, Ilex verticillata, and Nemopanthus mucronatus have very similar fruit. However, other characteristics make them easy to distinguish from each other. Ilex verticillata is a shrub that has deciduous, elliptic to egg-shaped leaves with sharply toothed margins and a hairy lower surface. Nemopanthus mucronatus is a shrub with deciduous, narrow elliptic to narrow egg-shaped leaves that have few teeth or non-toothed margins.

Flowering: May to June

Habitat and ecology: Moist woods and bottomlands.

Occurence in the Chicago region: non-native

Notes: This is a common landscape plant in the southern and eastern United States, with over 1,000 cultivars available. The branches are commonly cut from trees for use during the holiday season, and many bird species eat the fruit during the winter.

Etymology: Ilex comes from the Latin name of the holm oak (Quercus ilex), which has leaves similar to those in the Ilex genus. Thus, the genus Ilex was named after this species of oak. Opaca comes from the Latin word meaning "darker or dull," referring to the dullness of its leaves in comparison to the Eurasian species.

Author: The Morton Arboretum

Bushy shrub or small tree to 15 m; lvs evergreen, coriaceous, elliptic to oblong or ovate, 5-10 cm, tipped with a stout spine, and usually with 2-several strongly salient, spine-tipped teeth on each side; fls mostly 4-merous, the staminate in peduncled clusters; fr 8-10 mm, bright red (yellow); nutlets grooved on the back; 2n=36. Sandy soil near the coast from Me. to Md.; widely distributed in the s. states from Va. to Ky. and s. Mo., s. to Fla. and Tex. May, June.

Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.

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