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Scientific: Quercus ilex
Common: holly oak
Family: Fagaceae
Origin: Mediterranean region into central northern Europe. Here's an image of native stands of Quercus ilex on mountainous slopes in the very south of France.

Pronounciation: QUER-cus EYE-lex

Hardiness zones
Sunset
4-24
USDA 8-11

Landscape Use: Shade tree for large mesic and oasis landscape spaces, parks, green spaces, large residential yardscapes, lawn tree.

Form & Character: Upright and clean, bark of mature trees intensely striated, Mediterranean.

Growth Habit: Evergreen, woody, broadleaf perennial tree, moderately upright to 40- to 70-feet tall with slightly greater spread when fully mature.

Foliage/Texture: Elliptic-shaped leaves that are thick and leathery, persistant, with a pronounced midvein. Adaxial leaf surface is dark green, abaxial surface is tomentose and yellowish. Young developing leaves are pubescent. In local cultivation in southwest United States, leaf margins are smooth and entire tapering to a acuminate tip; medium texture.

Flowers & Fruits: Ornamentally inconspicuous.

Seasonal Color: None

Temperature: Tolerant

Light: Full sun

Soil: Tolerant

Watering: Infrequent deep summer irrigations to regular water is needed in Phoenix. Holly oak is tolerant of lawn conditions; also salt tolerant.

Pruning: In Phoenix, elevate canopy base (crown raise) very slowly and only as needed because the trunk is susceptible to sunscald.

Propagation: Seed, but seedling plants produce a deep taproot and need to be planted out into their permanent positions as soon as possible.

Disease and Pests: Spider mites when foliage becomes overly dusty.

Additional comments: Holly oak is an excellent selection for large mesic and oasis (greenery) landscaped spaces when a large tree with a regular, upright and spreading form is desired. In my opinion, holly oak should be planted more in mesic Phoenix landscapes. Other than trunk sunscald, this is a great, tough evergreen tree.