BEETLES INHABITING DEAD WOODY MATERIAL IN THE COMMERCIAL FOREST SPRUCE AND OAK COMPARED

With just 5-10 m3 of dead woody material per hectare, nature-oriented forestry practices may already provide an adequate environment for many beetles including faunistically important ones which inhabit dead woody material. For a considerable number of xylo-biont coleoptera, environmental conditions (degree of decomposition, and moisture) obviously play a more important role than the tree species does. From this may be concluded that also in the commercial forest stands which are diversely structured and uneven-aged will provide favourable conditions for preserving the beetle fauna which inhabits dead woody material. Results of these investigations indicate that the importance of stumps from cut trees for this particular beetle fauna has been underestimated thus far. This applies especially to large stumps, because they offer very diverse environmental conditions existing side by side over extended periods of time. The effect of such stumps can be increased by leaving higher ones (up to approximately 3 m) which regularly occur through wind and snow breakage.