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Abstract. This study suggests a method of valuation for wood coming from dead trees which was applied for pricing of such wood found in Polish forests. This study shows that in Polish forest there are approx. 52 million m 3 biocenotic wood coming from dead or dying trees with an estimated value of 1.5 billion PLN/10 years.

Pine stands at fertile sites need conversion into broadleaved or mixed forests. Yet, according to the age of stand, conversion may have different economic results. Therefore, in order to reduce costs of the process, the analysis on the basis of the potential income from wood sale has been done. The aim of the analysis has been to find an optimal date of conversion beginning. The date of conversion beginning has been fixed on the basis of the relation of the value of wood increment from the stands which need conversion to the value of average wood increment from stands conformable to the sites. By this means, three age intervals have been appointed.

The article presents some selected management problems in municipal forests occurring as a result of the increasing pressure on recreation and urbanization. The object of investigation was municipal forests of the city of Poznań. A thesis was formed that the consequences of the recreational pressure can be reduced through reasonable equipment of forest areas in appropriate recreational infrastructure. The second thesis put forward an assumption that an uncontrolled urban pressure posed a threat to the stability of ecosystems of municipal forests.

ABSTRACT:The author analyzes the changes in the tree species composition of Dentario glandulosae-Fagetum Klika 1927 em. Mat. 1964 in the mountain stands of Bieszczady National Park in 1993-2003. The analysis takes into account the changes over a ten-year period in the number and volume structure of each tree species in each stand layer: young natural regeneration, undergrowth, and mature stand. Additionally, after comparing the results with the natural Carpathian forests' structure, the adaptation level of the present tree species composition to the current climate and soil conditions, as well as probable directions of future changes have been assessed. A ten-year period is too short to find significant changes in stand species structure but it is possible to see some trends: beech share in stands is increasing and fir is decreasing.