The native forest of pines and oaks Quercus canariensis, Quercus lusitanica and Quercus suber are becoming rare in the Portuguese landscape. They have been replaced by fast-growing, non-indigenous, blue gum Eucalyptus globulus introduced to Portugal in the mid-19th century and now used for the production of wood pulp. At present these plantations occupy over 750,000 hectares and the negative effect of such management is obvious even to the most casual observer. The soil beneath the trees is stifled under a dense blanket of fallen slow-rotting leaves. Even in the most popular tourist destinations the harvested areas leave ugly scars. The trees are thirsty and hungry, drying the soil and altering it to infertile dust. They compete with native species and are reducing the biodiversity at an alarming rate. In addition, their volatile oil contributes to forest fires, adding further to the degradation of the environment.