San Lorenzo de El Escorial also has some allochthonous in its mountain areas, plant species as beech (American beech), cedars, larches, Lawson cypresses (Chamaecyparis lawsoniana), and sycamores (Acer pseudoplatanus).
There are also trees of historical significance, including giant sequoias (Sequoiadendron giganteum), planted in the 18th century in the parks and gardens of the Casita del Príncipe.