From Wikipedia:
The plant is evergreen, from 1 to 5 m high, with a strong smell of resin, growing in dry and rocky areas in Mediterranean Europe. It resists mild to heavy frosts but prefers milder winters and grows on all types of soils, and can grow well in limestone areas and even in salty or saline environments, making it more abundant near the sea. It is also found in woodlands, dehesas (almost deforested pasture areas), Kermes oak woods, wooded areas dominated by other oaks, garrigues, maquis shrublands, hills, gorges, canyons, and rocky hillsides of the entire Mediterranean area. It is a typical species of Mediterranean mixed communities which include myrtle, Kermes oak, Mediterranean dwarf palm, buckthorn and sarsaparilla, and serves as protection and food for birds and other fauna in this ecosystem. It is a very hardy pioneer species dispersed by birds. When older, it develops some large trunks and numerous thicker and longer branches. In appropriate areas, when allowed to grow freely and age, it often becomes a tree of up to 7 m. However, logging, grazing, and fires often prevent its development.