The cork oak forest is one of the major plant communities of the Mediterranean woodlands and forests ecoregion. In natural populations, the cork oak grows together with the holm oaks ("Quercus ilex", "Quercus rotundifolia"), the downy oak ("Quercus pubescens"), the maritime pine ("Pinus pinaster"), the stone pine ("Pinus pinea"), the strawberry tree ("Arbutus unedo") and the olive tree ("Olea europaea"), in cooler locations also with the sweet chestnut ("Castanea sativa"). In addition to these tree species, the shrub-forming species include the Kermes oak ("Quercus coccifera"), the holly buckthorn ("Rhamnus alaternus"), species of the genus "Phillyrea", the myrtle ("Myrtus communis"), the green heather ("Erica scoparia"), the common smilax ("Smilax aspera") and the Montpellier cistus ("Cistus monspeliensis") are often found together with the cork oak.