A boreal forest is a forest dominated by conifers, with a few deciduous trees. In Europe, the boreal forest is composed of deciduous trees (birch) and/or conifers and stretches from the Baltic to the Urals. Spruce is the most common conifer forming a dark, dense forest. Beyond the Urals, larch replaces spruce and the forest thins out as it moves eastward, until it becomes a very spare formation, a sort of wooded steppe in the mountains of the Far East. On the Chinese border, along the Amour river, the taiga becomes denser and more varied.