Ilex opaca Aiton

vernacular American holly — species · Aquifoliaceae

USDA: ILOP
GBIF: 5414248
Rank: species

American holly (Ilex opaca) — Platephotograph · dogtooth77CC BY-NC-SA source · iNaturalist ↗

§2Habit & range

Growth habit: Shrub, Tree
Duration: Perennial
Group: Dicot
Family: Aquifoliaceae Bercht. & J. Presl
Genus: Ilex

§2a

Native status, by region

L48 Lower 48 States Native

§2b

County-level range

· 4 counties across 1 state

Legend Native · 4 Introduced · 0 Both · 0 Hover a county for detail.

§3Cultivation specs · USDA

Recorded by the USDA Plant Materials Program.

§3a

Tolerances

Drought: Medium
Shade: Low
Moisture use: Medium
Fire: Low
Salinity: Medium
Anaerobic: Low
CaCO₃: Low
Hedging: Medium

§3b

Climate & soil

Cold tolerance: -20 °F minimum
Frost-free days: 140 min.
Precipitation: 40–80 in/yr
pH range: 4.5–7
Root depth: 30 in min.
Fertility need: Medium
Soil texture: coarse, medium

§3c

Form & growth

Growth form: Single Stem
Growth rate: Slow
Lifespan: Moderate
Mature height: 40 ft
Height @ 20 y: 20 ft
Foliage texture: Coarse
Foliage colour: Green
Porosity (summer): Dense
Porosity (winter): Dense
Flower colour: Yellow
Fruit colour: Red
Fire resistant: No
N fixation: None
Toxicity: None

§3d

Reproduction

Bloom period: Mid Spring
Seed abundance: Low
Seed begins: Summer
Seed ends: Fall
Spread rate: Slow
Stratify: Yes
Seeds / lb: 28,430
Propagation: seed, cuttings, bare root, container

§3e

Use & availability

Commercial availability: Routinely Available
Nursery stock: Yes
Browse palatability: Low
Graze palatability: Low
Palatable, human: No
Protein potential: Low
Lumber: No
Fuelwood: Medium
Christmas tree: Yes

§4Counties, by state

Recorded in 4 counties across 1 state.

Rhode Island view state ↗ 4 N ▾

§5Sources & provenance

USDA PLANTS

Symbol, taxonomy, distribution, cultivation specs, native status. Public domain.

plants.usda.gov/ILOP ↗

GBIF Backbone

Canonical taxonomic identity, synonym resolution, cross-refs. CC0.

gbif.org/species/5414248 ↗

Record version

Cached and built locally. Source version on this record:

usda-plants-mt-2026-05-25

fetched 2026-05-25T18:27:19Z