When using bending stiffness as a measure of wood decay it is advantageous to repeatedly test individual samples after they are exposed to decay fungi for varying periods of time. In order to obtain reliable results, variation in modulus of elasticity (MOE) values of the test samples that are repeatable bent to a given deflection must be considered. In this study it was shown that sound 3mm thick southern pine sticks could be deflected 2mm without exceeding the proportional limit. However, the MOE decreased slightly—approximately 3%--after three bending cycles. Sterilizing the samples by autoclaving resulted in a decrease in the MOE of approximately 10%, but no additional change in elasticity was observed when these sticks were repeatable deflected for six cycles. For decayed sticks, there was only a slight decrease in MOE when they were repeatedly bent for six cycles after the decay was arrested. The proportional limit of the decayed sticks subjected to 2mm deflection was not exceeded until the decay advanced to an MOE loss in the range of 40-50%.

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