Even though the study had to be limited to one stand for each of the two forest management systems, our results provide useful guide lines for more comprehensive investigations.
1. Clear differences were found in the reproduction pattern of two P. avium (wild cherry) stands. Particularly in the CWS, individual cloning success via root suckering was observed to exist at distinctly higher degrees compared to our investigations in a present-day HFS (group selection shelterwood system) which is believed to represent (near-) natural forest reproduction patterns. Further, the local formation of more than one asexual generation may be characteristic for CWS as is suggested by the large spatial spread and intermingling of several genets. An interesting aspect for more detailed investigations is to be seen in the fact that a reduction in genet number in combination with the spatial distribution of genets may lower mating opportunities due to the species' GSI system. This is in accordance with our observations of a reduced seed set in the CWS. Since the latter aspect applies more generally to fertilization success of self-incompatible tree species, it can be expected to have a significant effect on the sustainability of different forest management systems. The results obtained justify further studies on these topics, particularly if rare and endangered tree species of the Rosaceae family with similar reproductive features are considered.
2. This study demonstrates the importance of considering gene associations in addition to genic variation at individual loci in studies of multilocus genotypic structures. The newly developed "Type one error" method allows quantifying the lower level of multilocus gene associations within populations. In fact, this method may turn out to provide new insights into reproductive characteristics of species that have so far not been considered reproducing asexually. The method is also open to optimization, concerning the estimation of multilocus gene associations with the perspective of allowing more comprehensive insights into the organization of larger parts of the genome.
3. The observation that the largest genet is the one with the second largest degree of heterozygosity gives rise to speculations about associations between cloning success and degree of heterozygosity for cloning success. The fact that we found ramets of the same clone or genet separated by comparatively large distances suggests that these ramets are subject to larger microenvironmental heterogeneity. This in turn has been frequently argued to promote heterozygosity. If this would turn out to be relevant, it would suggest that cloning ability has an effect on heterozygosity comparable or even stronger than the GSI mating system (for an estimation the effect of the mating system see [22]).
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