Scots pine Pinus sylvestris is the most economically important tree species in Poland and most of Europe. Pine wood is valued for its quality and durability, and its properties have been well described for fresh wood from various locations with differing habitats and climatic growing conditions. However, there is a lack of data in the literature on the changes of physical and mechanical properties of pine wood following long−term storage. This is an important issue, as current climate change is leading to habitat changes and an increased frequency of insect pests, resulting in the gradual decomposition of tree stands and a potential need for optimal wood storage in forest depots. This study aimed to determine the density, modulus of rupture, and compressive strength along the fibres of pine wood stored for 60 months in two collection depots. The wood was processed from withered trees that had been separated in the stands of the Spała and Garwolin forest districts. In both storage depots, the wood was stored as 2.5 m−long roundwood stacked in piles 120 m wide and approximately 3 m high. The piles were divided into three layers: bottom, middle, and top. After 60 months, roundwood selected for analysis were tested, and the results indicated that the selected mechanical properties were only slightly – by a few percent – lower than those reported in the literature for fresh wood. Interestingly, 44% of the tested wood exhibited no visible defects, indicating a low rate of raw material depreciation. No clear influence of the geographical locations on the tested properties was observed, while wood from the bottom layer of the stack exhibited better property values. Wood from the central part of the bolt’s radius had superior properties compared to wood from the peripheral and core parts. Additionally, the identified wood defects (blue stain or rot) had no significant impact on mechanical properties. The research showed that, despite long−term storage without protection from weather conditions, the wood still constitutes a fully valuable raw material.

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