Resistance of acetylated wood to basidiomycetes, soft rot and blue stain

Poplar (Populus spp.), beech (Fagus sylvatica) and pine sapwood (Pinus sylvestris) samples were acetylated in a semi-industrial acetylation plant and tested for durability according to European standards. Resistance to Gloeophyllum trabeum, Coniophora puteana and Coriolus versicolor could be reached at a weight percent gain (WPG) of 12%. Susceptibility of acetylated pine to Poria placenta was higher and a WPG of 20% could deminish attack but not prevent degradation by this funguns. Soft rot resistance of wood could already be reached when acetylated to 10% weight gain. An outdoor exposure with acetylated poplar, pine and spruce showed no resistance to blue stain. A residual amount of acetic acid, formed during the reaction, could retard the discolouring by stain but not prevent it.