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Oak, Holly Quercus ilex

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Zones 7 - 11 Zones 7 - 11
Hardiness Zones 7 - 11
The Holly Oak can be expected to grow in the zones shown in color in the arborday.org zone map. View Map
Evergreen Evergreen
Type of tree
Evergreens
40' - 70' High 40' - 70' High
Mature Height
The Holly Oak grows to be 40' - 70' feet in height.
50' - 60' Spread 50' - 60' Spread
Mature Spread
The Holly Oak has a spread of about 50' - 60' at full maturity.
Slow to Medium Growth Slow to Medium Growth
Growth Rate
This tree grows at a slow to medium growth rate. More about this.
Full Sun Full Sun
Sun
This oak does well in full sun.
Various Soils Various Soils
Soil

The holly oak tolerates a wide range of soil textures from acidic to slightly alkaline, salt, and drought.

Rounded Shape Rounded Shape
Shape
This oak has rounded shape.
Attributes

The Holly Oak is a long lived, durable tree that will thrive in almost any location once established and stands up well to strong winds. It provides shade for large areas of the landscape.

Description

The holly oak is a tough evergreen tree as wide as it is tall with a dense rounded crown. It has smooth gray bark. The leaves are a leathery, glossy, dark green and vary in size and shape. The margins may or may not be irregularly toothed. Acorns are produced in the firat year falling in autumn. Holly oak tolerates a wide variety of soil textures, salt, and drought, but is sensitive to cold. It requires regular watering until it is established and then should not be overwatered as this invites powdery mildew. Be sure to keep irrigation away from the base of the trunk as root rot can set in. It may require pruning when young to develop a strong branch structure. If left unpruned it can develop multiple leaders and take on a large shrub form. When given adequate soil space, it does well along streets and parking lots, and in parks and gardens in the western United States.

Wildlife Value

Birds and squirrels are attracted to the holly oak for food and shelter.

History/Lore/Use

Holly oak is native to the Mediterranean region. The range is from Spain along the Mediterranean fringe east towards western Pakistan. Other common names are Holm oak and Evergreen oak. In the foothills of the Spanish Pyrenees, black truffles are grown on the roots of these trees.

Moisture

The Holly Oak thrives in moist, well-drained soil, but can tolerate drought when established.

Leaves

The leaves are alternate, simple, 1"-3" long, spine-tipped teeth or untoothed along the margin, leathery, glossy dark green above, gray-green and downy below. They have a stiff, holly-like texture.

Flower Color

Male flowers are drooping catkins, female are inconspicious.

Bloom Time

In spring.with the new leaves

Fruit Description

The Holly Oak produces elongated acorns 1" long, green-yellow and brown. Acorns mature in the first year.