Changed susceptibility of the chemically and thermally degraded spruce wood to its attack by the dry rot fungus Serpula lacrymans
IRG/WP 99-10322
L Reinprecht
In buildings, some intentional or unintended situations can occur at which some wood products are exposed to aggressive chemicals and also to higher temperatures. Occasional activity of fungi on such pre-attacked wood products can be either higher or lower. This paper deals with changes in the susceptibility of spruce wood (Picea abies L. Karst.) to attack by the dry rot fungus Serpula lacrymans, in such situations, when the wood samples 8.5x8.5x120 mm3 (RxTxL) were first pre-treated with 1% water solutions of selected acids (H2SO4, CH3COOH), bases (NaOH, NH4OH) or oxidizing agent (H2O2), or they were also exposed to a higher temperature (190°C/3h). The activity of S. lacrymans was totally restricted only in one situation, if the wood was pre-treated with sulphuric acid and then exposed to 190°C. On the other hand, specimens pre-treated with ammonium hydroxide were more susceptible to bio-attack (in both situations: without or with high temperature pre-treatment effect) than sound ones.
Keywords: NORWAY SPRUCE; AGGRESSIVE CHEMICALS; HIGH TEMPERATURE; ROT; SERPULA LACRYMANS