Mixed forest is a mostly colloquial term that describes forests in which several tree species z. B. deciduous and coniferous trees occur together. From an ecological point of view, the prerequisite is that each tree species is sufficiently available to assume a species-specific role in the ecosystem. The timber device speaks of mixing stocks , once the admixture is at least 5% of the area. Smaller admixtures are regarded as ecologically insignificant and are therefore not taken into account.
Mixed forests can be divided into mixed deciduous forests , in which predominantly or exclusively different deciduous tree species occur, and in coniferous mixed forests , in which predominantly or exclusively different conifer species occur.
In forest science and vegetation science , the term mixed forest is only used very rarely without further additions. Instead, more precise terms such as pedunculate oak-hornbeam-forest or alder-ash-alluvial forest are used. However, the expression mountain mixed forest, for mixed forests of spruce, fir and red beech, often with the participation of other species, is common in the montane altitude range of the southern German low mountain range and the Alps.
The German National Forest Inventory defines mixed forests as follows: There are trees from at least two botanical genera , each with at least 10 percent surface area. According to the Third National Forest Inventory (2012), 76 percent of German forests are mixed forests. In the period between 2002 and 2012, the proportion of mixed forests in Germany increased by 5 percent.
The term mixing was used as a contrast to the pure stand. No distinction is made here between deciduous and coniferous trees.
- Federal Ministry of Food and Agriculture (BMEL) (ed.): The forest in Germany - selected results of the third national forest inventory , p. 19.