Selective forest health felling in protective Siberian stone pine stands of Khakassia: an experience of post-logging survey and silvicultural analysis

On the example of three areas of protective Siberian stone pine Pinus sibirica Du Tour stands of Khakassia, the expediency of selective forest health felling is considered. Forest growing conditions on the plots are favorable for dark coniferous Siberian stone pine-fir forests. A distinctive feature of precutting and postcutting stands is their sparseness. As a result, exceptional (often more than 1 m) stem diameters were formed. Over the four years that have passed after the felling, the tendencies of the forest-forming process have become quite distinctly outlined, which actually made it possible to assess their consequences. On the basis of the data of full-scale survey – a continuous count of stumps and data from strip test plots – the inventory indicators of pre-cut and post-cut forest stands, the volume and marketability of the wood removed and left on the root were revealed. The absolute completeness was restored according to the measurement data of the stump diameters. It is shown that the transition from stump diameters to DBH is accompanied by systematic errors. To determine DBH, the dependences DBH = f (d0) were formed on the basis of model Siberian stone pine and fir Abies Mill. trees. It has been established that an increase in core rot occurs synchronously with an increase in the diameter of the stem, therefore, trees of lower thickness steps are more likely to be classified as commercially valuable trees. During the allocation of cutting areas, the trees to be selected were not marked. Thus, the logger was given the opportunity to choose trees for felling. As a result, a targeted selection of commercially valuable stems was made; the half-timber and wood-logged sems partially remained intact, partially not removed from the plots or burned as felling remains. Such felling definitely does not correspond to the «forest health» category. It has been shown that the efficiency of performing soil-protective and water-protective functions by post-felling stands, even with a predicted conversion to meadows, remains comparable to the previous, pre-felling stands. At the same time, the Siberian stone pine stands are more valuable for forest animals. Hence, it follows that the undertaken action – forest health felling of the Siberian stone pine stands was inappropriate