Scots pine (Pinus sylvestris L.) demonstrates a high resistance against bark stripping damage

Abstract

Bark stripping damage reduces timber quality due to fungal infection and structural defects. Weakened stems may break and induce the death of trees, which strongly affects forest stability. Some tree species, such as Norway spruce (Picea abies [L.] Karst.), are highly susceptible to bark stripping, but Scots pine (Pinus sylvestris L.) has been studied to a lesser extent. The objective of this study was to predict the effect of the degree of bark stripping damage and rot on the production parameters of Scots pine and to determine the influence of climatic factors on various damaged trees. The research was conducted on 15 pine forest stands aged 40–42 years with a numerous sika deer (Cervusnippon nippon) population in the western part of the Czech Republic (425–492 m a.s.l.). The results showed significant differences in tree diameter and volume (but not height) between healthy and extensively damaged trees according to 417 pines measured. However, no differences were found between lightly damaged trees. Similarly, circumference damage did not significantly affect mean tree stem volume, in contrast to previously reported results for Norway spruce. The trees were first damaged by deer at the age of 18.5 years on average. According to the prediction model based on 40 felled and sampled trees, rot did not reach a distance > 50 cm from the site of the bark stripping on the stem, with a mean speed of vertical spreading of 0.9 cm yr−1. Concerning the effect of climatic factors on radial growth (60 core samples taken), the difference between healthy and minor to extensively damaged trees was negligible. However, healthy trees responded more to the effects of temperature, and damaged trees were more sensitive to the precipitation amounts. Scots pine appears to be a suitable tree species for afforestation in areas with high game pressure during continuing climate change.