Holm Oak (Quercus ilex)

/ / Trees and Shrubs


Species from the genus Quercus can be found within the Family Fagaceae.  There are as many 600 different species within the genus and they are mainly found in the Northern Hemisphere, yet can also be found in Polynesia (1).  Similar species to Q. ilex include; Q. coccifera and Q. rotundifolia, the latter it can interbreed with (2)Q. ilex can be found as a shrub or small tree, but can grow into a large tree 15 to 27 m (2).  Its leaves are dark green above and grey-green beneath.  They vary widely in size and shape, often on the same tree.  They are normally either entire or toothed.  The acorns are ovoid and sit in a cup of overlapping scales (3).

Life Cycle

It is a deciduous (3) slow growing tree (2).  However root growth is fast.  For example in one year the unbranched taproot of a seedling can reach 60 to 80 cm (2).  Growth occurs predominantly between May and June.  Maximum leaf fall occurs between the same time to coincide with the growth of new shoots.  Leaf lifespan ranges between one and four years (2).  Flowers appear mostly in May and last until late June, when acorn growth occurs.  Acorns fall between November and January, greatest fall occurs every two to four years (2).


It is a shade tolerant tree which can become dominant in late successional stages.  It is drought resistant (2).


Quercus ilex grows throughout Greece and the Mediterranean region (3).  It is rarely in altitudes lower than 350 m and can be found up to and beyond 1800 m.

Conservation status

Quercus ilex forests are protected under Annex I of the Habitats Directive, ref: 9340


Description written by Amy Trayler (2009)

(1)   About Oak Trees (2003) Introduction [online] Available:
http://www.about-oak-trees.com/index2.htm [date accessed: 07/05/2009]

(2)   Terradas. J. (1999) Holm Oak and Hold Oak Forests: An Introduction, In Ecology of Mediterranean Evergreen Oak Forests – Ecological Studies, Vol. 137, Analysis and Synthesis, (eds Roda, F., Retana, J., Gracia, C.A., Bellot) Ch 1, pp 3-14, Springer, Berlin

(3)   Sfikas. G. (2001) Trees and Shrubs of Greece, Efstathiadis Group S.A., Greece