Fig. 4From: Effect of oil impregnation on water repellency, dimensional stability and mold susceptibility of thermally modified European aspen and downy birch woodMold grades of the thermally modified (TM) and non-TM samples impregnated with three different oils after an incubation period of 21 days in a climate chamber at 27 °C and 92% relative humidity (RH). Unimpregnated samples from non-TM material of aspen and birch are regarded as control. Vertical bars represent the standard deviations. Different letters indicate a significant difference by Duncan’s homogeneity groups (P ≤ 0.05)Back to article page