Key Figures on Forest Genetic Resources
The range of species in forest in Germany is comparably limited. In the temperate zone of Europe there are only about 80 indigenous tree species. Other regions, exempli gratia the East of the USA, come up with about 250 species.
The decisive factor for this relative poverty of species were the ice ages. The barrier effect of the Alps as "dividing beam" led to a species impoverishment during the resettlement in the interglacial periods. Today's distribution of tree species in Germany, but also their genetic diversity were crucially determined by remigration, especially bypassing the Alps in the East.
However, forest vegetation in Germany is dominated by the tree species of Norway spruce, Scots pine, Common beech and oak (Sessile and English oak). These take up 78 % of the surface in forests.
The potential natural forest vegetation in Germany, i.e. without human influence, would come to a share of deciduous forest of about 90 %, characterized by beech and oak forests.
With the beginning of a controlled forestry 200 to 250 years ago, fast growing conifers were preferably chosen for the setting up of forests (spruce as the "Brotbaum" [high yield tree] of forestry"). This is today still testified by the significant portion of the two coniferous tree species of Norway spruce and Scots pine, which together account for over 50 %.
Alongside the indigenous forest tree species, numerous foreign tree species are successfully cultivated in Germany, and used in forestry. These are partly to be regarded as neophytes, especially if they are competitive and able to become naturally rejuvenated. Examples are Douglas fir, Red oak, Robinia and Chestnut.
*) Schmidt, M.; Ewald, J.; Fischer, A.; Oheimb, G. V.; Kriebitzsch, W.-U.; Ellenberg, H.; Schmidt, W. (2003): Liste der Waldgefäßpflanzen Deutschlands - In: Mitteilungen der Bundesforschungsanstalt für Forst- und Holzwirtschaft - v. 212, 35 p.