DEAD WOODY MATERIAL OF NORWAY SPRUCE CAUSE FOR STRAINED RELATIONS BETWEEN NATURE CONSERVATION AND FORESTRY

Over a period of two growing seasons, 36 samples of spruce dead woody material (bole parts, branchwood, stumps) were continuously exposed as traps, using tent photo-eclectors. Two spruce stands of a commercial forest area, containing different amounts of dead woody material, had been selected as experimental areas. The large number of identified species - 173 beetle and 181 dipterous species - speaks for the importance of spruce dead woody material also as a habitat for saproxylic insects; and this the more so as the pattern of the species/substrata curves makes one to expect an even higher species potential. Leaving spruce dead woody material in the stands principally will bear a forest protection risk; yet it seems possible to keep this risk within tolerable limits if the date of death is being considered. Smaller stands with only little dead woody material within areas with relatively large amounts of such obviously do not constitute an interruption in terms of species abundance.