This study provides an operational-scale assessment of internal decay caused by Porodaedalea pini in managed Scots pine stands based on data collected during harvesting operations. Unlike previous studies relying on indirect indicators such as fruiting bodies, this work quantifies the actual proportion of logs affected by decay under real-world production conditions. Although the mean decay share was relatively low (3.29%), substantial variability among stands was observed. A moderate relationship between stand age and decay occurrence was detected; however, statistical models showed limited explanatory power, highlighting the influence of additional stand-level factors. A potential threshold around 110 years may indicate an increased risk of decay in overmature stands. These findings underline the importance of incorporating decay risk into forest management decisions while acknowledging the uncertainty associated with predicting internal decay under operational conditions. These results may support forest management decisions regarding rotation age and timber quality risk assessment.
Szewczyk et al. (Wed,) studied this question.