Vegetation in Europe was completely formed after the quaternary glaciations. Throughout human history vegetation underwent major changes caused by human activity. In many areas crops largely replaced wild vegetation. Many crops originated in Europe. The islands in the Arctic Ocean belong to the Arctic Wasteland Zone and are devoid of trees and shrubs. Lichens and mosses predominate there. The Tundra zone covers the northernmost parts of the Russian plain, the Kola Peninsula and the Scandinavian Peninsula as well as coastal Iceland. There prevail shrubs, mosses, lichens and marsh vegetation. To the south lies the alpine tundra sub zone. In the temperate latitudes of Europe is the forest zone, which is divided into the following sub zones: taiga, mixed forests, broadleaf forests, forest-steppe, steppe, semi-deserts. The taiga belt stretches for example south of 57-60° latitude. There mostly grow European fir and pine, Siberian fir and larch, and in the mountainous regions grow tundra vegetation birches. The mixed forests sub zone includes the northern parts of the UK, Southern Scandinavia, Northern Germany and the Russian plain and extends south to 52-54° N. The vegetation typical for this sub zone are forests of oak, linden, maple, ash, beech, fir, pine. The sub zone of mixed forest is most prominent in Western and Central Europe, and in the northern parts of the Balkan Peninsula. It mainly consists of beech and oak forests with occasional linden, ash-tree, maple, hornbeam and chestnut stands. The forest-steppe sub zone is typical for the southern part of the Russian Plain and the central parts of the Danube lowlands. To the south the forest-steppe transforms into steppes, dominated by grassy areas. Steppes are most prominent in Ukraine and the Volga region, and a narrow steppe strip stretches along the northwestern coast of the Black sea down to Bulgaria. The semi-deserts sub zone occupies a small area in the southeast of the Volga region and is characterized by vegetation typical for dry lands and some steppe grasses. The Mediterranean sub zone has various types of forests for example oak and pine, as well as evergreen shrubs. The vegetation in the southern part of the Iberian Peninsula mostly consists of dwarf shrubs.