Sustainable forest management should take into account the principles and requirements of the conservation of forest genetic resources. In Germany, the focus is lain on in situ measures for the conservation of forest genetic resources. This is supplemented by the implementation of gene conservation units and ex situ measures (e.g. seed storage, seed plantations). Regarding the main tree species (spruce, pine, beech and oak), conservation is carried out primarily within the framework of sustainable forest management through/by preservation and natural regeneration as well as sowing and planting with site-adapted forest reproductive material.
Until 2013, more than 320 in situ measures had been carried out on an area of more than 32,600 ha for approx. 100 tree and shrub species. In addition, there were more than 100 ex situ measures, covering an area of 1,250 hectares for around 55 tree and shrub species.
In the case of rare tree and shrub species, the specific documentation and genetic characterisation of the populations are usually necessary in order to decide on conservation measures, e.g. conservation plantations. Tree species are considered rare if they have an area share of less than 1%. Often they are also threatened in their preservation, especially in the peripheral areas of their natural distribution.
Within the framework of surveys and genetic research, the following native and rare species have been studied throughout Germany: Common yew (Taxus baccata), wild service tree (Sorbus torminalis), field maple (Acer campestre), downy oak (Quercus pubescens), European bird cherry (Prunus padus), green alder (Alnus viridis), gray alder (Alnus incana), service tree (Sorbus domestica), wild apple (Malus sylvestris) and wild pear (Pyrus pyraster).
In general, special measures for the conservation and sustainable use of forest genetic resources are nessesary. The most important measures are:
- Identification and evaluation of existing forest genetic resources (inventories, phenological and genetic characterisation)
- In-situ measures (natural regeneration, conservation of stands and individual trees, sowing and planting in the forest)
- Ex-situ measures (seed orchards, clone collections, seed and pollen storage, generative and vegetative propagation)
- Conservation within forest management (regeneration, silvicultural treatment, harvesting)
- Joint research projects.
Within the framework of multifunctional forestry, the sustainable utilisation of forest genetic resources serves for the functions of production, protection and recreation of the forest. In addition to the location and silvicultural treatment, the highest possible biological diversity of the forests forms a crucial basis for their efficiency and performance. Above all, genetic adaptability and adaptability guarantees the stability of forests that is necessary for all uses. In particular, they ensure the forests' ability to react through resistance to damage from biotic and abiotic factors. The climate change that is taking place is resulting in increased requirements.