Holm oak

It is a large evergreen tree, attaining in favourable places a height of 21–28 metres (69–92 feet), and developing in open situations a huge head of densely leafy branches as much across, the terminal portions of the branches often pendulous in old trees. The tallest recorded, a tree planted at Windsor Great Park, is 30.4 m tall. The trunk is sometimes over 6 m (20 ft) in girth. The young shoots are clothed with a close grey felt. The leaves are very variable in shape, most frequently narrowly oval or ovate-lanceolate, 4–8 centimetres (1+1⁄2–3 inches) long (rarely to 10 cm long), 2–5 cm wide (rarely to 8 cm wide), rounded or broadly tapered at the base, pointed, the margins usually entire on mature trees, or (especially on young trees) more or less spiny-toothed. 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; on the lower surface it turns grey or tawny, and persists until the fall of the leaf; the petiole is 3–16 millimetres (1⁄8–5⁄8 in) long. The acorns are produced one to three together on a short downy stalk, ripening the first season; they are usually 12–20 mm long in the UK, the cups with adpressed, downy scales, and an often wavy margin.

Holm oak grows in pure stands or mixed forest in the Mediterranean and often at low or moderate elevations, but also at higher altitudes in the Atlas Mountains. It is native from westernmost Turkey and through Greece west to parts of the Iberian Peninsula, where it mixes with Q. rotundifolia, along the northern Mediterranean coastal belt, and in the Atlas Mountains in Tunisia and Algeria.

The wood is hard and tough, and has been used since ancient times for general construction purposes as pillars, tools, wagons (as mentioned in Hesiod, Works and Days on page 429), vessels and wine casks. It is also used as firewood and in charcoal manufacture. The holm oak is one of the top three trees used in the establishment of truffle orchards, or truffières. Truffles grow in an ectomycorrhizal association with the tree's roots.

The first trees to be grown from acorns in England are still to be found within the stately grounds of Mamhead Park, Devon. From Britton & Brayley in The Beauties of England and Wales (1803):The woods and plantations of Mamhead are numerous and extensive. Many of them were introduced by Mr Thomas Balle (sic), the last of that family who, on returning from the continent, brought with him a quantity of cork, ilex, wainscot, oak; Spanish chestnut, acacia, and other species of exotic trees. Holm oak is not officially listed as an invasive species in the United Kingdom but is naturalised, able to naturally regenerate. Normally the tree is unable to withstand severe frost, which would prevent it from spreading north, but with climate change, it has successfully penetrated and established itself in areas north of its native range. The largest population of holm oak in Northern Europe is present on and around St. …

The resemblance of the foliage to that of the common European holly, Ilex aquifolium, has led to its common and botanic names. The species name ilex was originally the classical Latin name for the holm oak, but later adopted as a botanical genus name for the hollies. The common name 'holm oak' takes its name from holm, an ancient name for holly.