## 4 Discussion
The losses in height increments of the damaged trees are far lower than in the case of the diameter at breast height and amount to 8.6% as compared with the undamaged trees (Table 2). A similar observation was made by [PERSON] et al. [70], who noticed that older pine stands (aged between 40 and 42 years) do not show significant differences in height between healthy and debarked trees. [PERSON] [72] concluded that a significant deceleration in height growth occurs in the first year following debarking, with the growth mostly returning to normal after the third year. [PERSON] [73] claims that the deceleration in height growth is noticed up to a maximum of 5 years after debarking. Finish studies show the height development of the European spruce axis trunk diminished by ca. 15% [74]. [PERSON]'s research [75], on the other hand, confirms debarking causes an average deceleration of the growth in pines by 12%. The 7-year-old pine sapling stand manifested height increments decelerated by 14% in relation to the undamaged trees [71]. The mean damage-induced growth reduction in \(G_{1.3}\) of the analysed tree stands was 39%. Ebis [76] reports \(G_{1.3}\) diminished by 20% through bark stripping in a 30-year-old pine stand. The forest economy suffered losses as a result of bark stripping, which are best reflected in the calculated volumes. As in the case of other productive parameters, the tree stand volumes assumed lower values in the debarked stands in comparison with the expected volumes for a given age and valuation class. The large timber volume recorded in Tables of Stands Volume and Increment [77] for 35-year-old pines is 287 m\({}^{3}\)-ha\({}^{-1}\) with the density of 1566 trees\(\cdot\)ha\({}^{-1}\). The aggregate volume of the tree stands obtained in the first approximation (Table 3) is comparable to the one reported in the resource tables [77]. What is worth noting, however, is that the obtained volume is composed of a much higher number of trees per hectare (1800-3400 trees-ha\({}^{-1}\)). Hence, it can be concluded that the trees under analysis have lower biometric parameters, especially DBH. The losses that forest economy can suffer through damage caused by deer also include technical shortcomings of the wood, manifestable only after logging. This is all the more important considering the fact that as many as 75% of the calculated volume can have such defects. According to a study by [PERSON] and [PERSON] [78], compared to biometric parameters, bark stripping may have a more significant impact on the quality of the wood, causing stain to spread around wounds and irregularities in the grain due to occlusion processes. The development of alternative methods to manage and control the deer population on this territory is necessary in light of the extensive bark stripping that was discovered in this study. [PERSON] [30] concluded that high levels of bark-stripping occurred in mono-specificstands and primarily in age class stands associated with poor food availability compared to multi-specific stands with different storeys. This stresses the need to consider both the density of deer, food resource availability and their interaction to reduce the intensity of bark stripping. Supplementary feeding of red deer, aimed at deflecting red deer damage, is widespread in the study area. The presented high levels of bark stripping, however, suggest that supplementary feeding did not prevent deer from stripping bark. A rational way to minimise damage in the forest economy is to perform intermediate cuts in the winter period. Leaving timber lying on the ground for a time will provide deer with coarse fibre fodder and minimise the stripping of trees intended for further cultivation.