In 9 Norway spruce stands from different growth regions in Southern Germany, which were provided for clear cutting and where considerable damage by red rot was supposed, on experimental plots all trees before felling were surveyed respecting species, diameter, tree-class and soundness. After felling, the stems were tested for fungus attack, the types of rot (root rot or wound rot) were registered, the degree of the damage was determined and the responsible wood-destroying fungi were identified. In all localities almost the same species of fungi were found, but their quote differed considerably according to the predominating type of rot. At some of the investigated stands spruce was not very resistant to root rot, at others—in spite of good nitrogen nutrition—the diseases only resulted from wounds; rots starting from the roots were seldom found. These differences observed in several stands are discussed. Statistical calculations have shown, that the correlation between the degree of decay on the stump and the height of the rot depends on the site. Therefore an estimate of the amount of rotten wood on account of the extent of decay on the stump, certainly is possible for individual stands, but not in universal view.