The initial conditions for taking measures aiming at the maintenance of forest genetic resources in Austria are characterized by a very differentiated environment and a relatively high share of nature-conforming forest stands. These diverse requirements to adaptability indicate a corresponding multiplicity of genetically controlled traits, in particular for the distribution along an altitudinal cline of tree species with a wide altitudinal coverage, where this has been proved with respect to phenological and morphological traits.
In the absence of suitable genetic markers with adaptational significance, the structure of natural forest communities - containing altitudinal zones, forest ecoregions, and potential natural vegetation - can be used for the selection and delimitation of gene reserves. It is assumed that the existing genetic structures are sufficiently covered through the dispersion over ecologically and plant sociologically defined units.
The network of forest gene reserves in commercial forests is to supplement the network of natural forest reserves, because in natural forest reserves possibilities for gene conservation may be limited as a result of active measures being prohibited.
Apart from the minimum size, the selection criteria for gene conservation units include the favourable distribution of the formation phases of a stand and its state of natural regeneration. Silvicultural planning is adjusted to the requirements of gene conservation.
Considerable research work needs to be done to check and improve the selected approach and, in particular, to assess the genetically adaptive capacities.