Southern coniferous forest zone, also known as the boreo-nemoral region, the southern coniferous forest zone is delimited by the oak's northern natural limit (''limes norrlandicus'') and the Spruce's southern natural limit, between the southern deciduous zone and the Taiga farther north. In the southern parts of this zone the coniferous species are found, mainly spruce and pine, mixed with various deciduous trees. Birch grows largely everywhere. The beech's northern boundary crosses this zone. This is however not the case with oak and ash. Although in its natural area, also ''planted'' Spruce are common, and such woods are very dense, as the spruces can grow very tight, especially in this vegetation zone's southern areas.