Investigations on the Storage Behaviour of Roundwood from Healthy and Diseased Beeches

Abstract

Healthy and variously diseased beeches were felled in March 1985 and were stored, with bark, on supports during the summer months in order to study any effects of disease on storage behaviour. By repeatedly taking disks from stored logs, visible storage defects were registered, moisture content of the wood was determined, and the wood inhabiting microflora was studied by systematic isolation from the wood. Two to three months after felling insignificant brown stained zones appeared in the uppermost sapwood and some minute brown specks were distributed over the entire cross section, which tended to spread over large areas during the storage period. Finally, white rot fungi occasionally destroyed smaller or larger zones between the discoloured brown ones, in initially healthy beeches just as much as in damaged ones. W ood staining microorganisms can only partly be made responsible for these considerable discolorations. Although blue staining fungi had occupied an important position in all logs under study, fungal hyphae were only rareIy found in the dark brown zones even in advanced stages. Here only a profuse formation of tyloses and an increase as weil as oxydative dark staining of the parenchyma cell contents was noticed.