Potential for Expanding Summertime Timber Harvesting on Drained Peatlands Under Operational Stand Conditions: A Site-Specific Case Study

The expansion of sustainable timber harvesting on peatland forests is important for forest owners, contractors, and the forest industry. This study investigated the effects of site-specific conditions on summertime harvesting operations and modeled the influence of a light nine-ton forwarder on rut formation. Three logistic mixed-effects models predicted peat surface disturbance (ROC = 0.60, 0.63, and 0.67), while a linear mixed model predicted rut depth when rutting occurred (R2 = 0.35). Rut formation was associated with the number of machine passes, cumulative load, groundwater table depth, peat layer thickness, and interactions between stand and harvesting variables. The results indicate that timber can be successfully forwarded from drained peatlands with limited bearing capacity when operations are adapted to local site conditions. The findings highlight the importance of road-network planning, load management, and operator decision-making in reducing rut formation. This modeling approach also supports operator training, thereby contributing to more sustainable timber harvesting on low-bearing-capacity sites.