ENHANCED TERMITE RESISTANCE OF SCOTS PINE (PIN US SYLVESTRIS L.) SOLID WOOD BY PHENOLFORMALDEHYDE TREATMENT

In order to assess the resistance of phenol-formaldehyde (PF) modified wood to subterranean termites (Reticulitermes flavipes), laboratory no-choice tests following the standard EN 117 (2013) were performed for 8 weeks. Scots pine (Pinus sylvestris L.) sapwood specimens were modified with low molecular weight PF-resin in two concentrations. After vacuum-pressure impregnation and curing, the wood specimens were subjected to an accelerated aging test according to the standard EN 84 (1997). Five replicates per each concentration group were exposed to termites as well as unmodified wood. Following exposure, the specimens were evaluated for termite damage using a visual rating system and mass losses were also recorded. All treated samples showed higher resistance to termites than the controls. After testing period, 100 % termite mortality was found for modified wood. PF-resin treatment significantly reduced the feeding activity of termites and the mass losses caused.