The mean volume of stands with fir and beech in their species composition in the study plots Święty Krzyż 1 and Święty Krzyż 2 was 521 m3/ha and 203 m3/ha respectively. These stands were many-storeyed and of many generations with the structure of the distribution of trees by d.b.h. close to Liocourt-Meyer curve. In volume of standing dead trees and dead wood laying on the ground, amounting together to 41.1% of stand volume of living trees in the plot Święty Krzyż 1 and 171.6% in the plot Święty Krzyż 2, predominated fir 99.4% and 100% in total volume of standing dead trees, and 46,2% and 82% in total volume of laying dead wood in respective plots. Fir was most abundant in the new growth layer (78.3% in the plot Święty Krzyż 1, and 39% in the plot Święty Krzyż 2), while beech decidedly dominated in the upgrowth layer (54.2% and 50.8% in respective plots). The stand in the plot Święty Krzyż 1 was considered to be in the growing up stage with the phase of storeyed form, while the one in the plot Święty Krzyż 2 in a transitional stage between the break up stage and the growing up stage with an intermediate phase between the regeneration phase and the phase of storeyed form.
Investigations were carried out in series of 6 permanent study areas (5 in forests of primeval character, and 1 in a managed stand) with the growing stock ranging from 226 m3ha-1 to 593 m3ha-1. These stands were characterized by a considerable differentiation of the tree d.b.h. and a complex storeyed structure, resembling a selection forest. Only two stands reached the growing stock close to the one accepted as the optimum for the beech selection forests. When carrying out a selection cutting in such forests one should take the lowering of the growing stock to about 220/250-300 m3ha-1 into consideration. It would be more correct, therefore, to carry out in managed beech forests a Swiss irregular shelterwood system, rather than a selection cutting system. The latter one may be used in the beech stands of differentiated structure in protection forests or in forests of a special purpose.