Italy's Natural Vegetation
Man's intense exploitation over many thousands of years has greatly altered the original condition of the vegetation cover, this is true also for the high mountain zones of the Alps and Apennines, which were subject to systematic deforestation until the end of the last century. Despite massive attempts to protect the mountains from the beginning of this century, many of Italy's mountain regions still remain without tree cover and are therefore susceptible to hydrogeological disaster, especially in the zones with particularly unstable rock types. At the present time little more than a fifth (21.2%) of Italy is covered by trees, which altogether occupy an area of circa 64 sq km. In the strictly floral category, the region of Italy unites Mediterranean and central European species. When these are combined with morphological and altimetrical influences a varied floral landscape results that is more dependant on climatic conditions than soil types. Thus it is possible to identify at least four principal floral regions. 1) An Alpine region, divided into bands according to height, with oaks and other broad-leaved trees prevailing in the lower areas and valley bottoms, followed up to circa 1,000 m by chestnuts and then beeches followed still higher up, but not beyond 2,000 m., by a mixture of needle-leaved trees (firs, larches and Scotch pines); the summit areas are dominated by meadows and pastures together with shrub vegetation (rhododendrons and dwarf pines) or, on the margins of permanent snow (circa 2,400-2,800 m.), by Alpine tundra with mosses and lichens. 2) An Apennine region, similar in character and sequence to the Alpine but with the presence of temperate species in the valley bottoms and a lesser spread of conifers in the upper levels. 3) A Po region, dominated by broad-leaved trees (willows, alders, poplars and oaks), which still form small woods but only along the river banks, while on the upper plain survive extensive stretches of the original heath with American acacias, heathers and brooms. 4) A Mediterranean region, covering the Ligurian and Tyrrhenian coasts as well as those of the central and southern Adriatic and the islands, dominated by a mixture of maritime pine and evergreen macchie (with olives, cypresses, corks, etc.) derived from the spoiliation of the original ilex groves.