Ailanthus altissima
A few Old-growth forests (known locally as "fragas") remain, particularly in the lower parts dominated by the English oak ("Quercus robur" L.), mixed with other trees like: alders, birches, ashes, hazels, blackthorns, maples, willows, wild cherry trees, wild pear trees, etc. Hills are covered mainly by maritime pine trees ("Pinus pinaster"). As exotic species are blue gum ("Eucalyptus globulus"), black locust or false acacia ("Robinia pseudacacia") and recently the invasive heaven tree ("Ailanthus altissima"). It is also frequent the American northern red oak ("Quercus rubra") in new forest plantations. Shrubs (holly, hawthorn, blackberry, ivy, dog rose, elder, laurel bay, Scotch broom, gum rockrose or gorse) and herbaceous are also important. Lira also has a good range of heathers, ferns and mosses species.