Quercus ilex is a large evergreen oak native to the Mediterranean region. The resemblance of the foliage to that of the common European holly, Ilex aquifolium, has led to its common and botanic names.
An evergreen tree of large size, attaining a height of 21–28m, and developing in open situations a huge head of densely leafy branches as much across, the terminal portions of the branches usually pendulous in old trees. The trunk is sometimes over 6 m in girth.
The young shoots are clothed with a close grey felt and the leaves are very variable in shape, most frequently narrowly oval or ovate-lanceolate, rounded or broadly tapered at the base. When quite young, both surfaces are clothed with whitish down, which soon falls away entirely from the upper surface leaving it a dark glossy green.
Fruits are produced one to three together on a short downy stalk, ripening the first season, the acorn cups with appressed, downy scales.