Douglas-fir – partial substitution for declining conifer timber supply – Review of Czech data

The decrease is supposed of the coniferous assortments supply due to running changes of tree species composition in the Czech forests as well as due to the environmental changes in the next decades. The Norway spruce (Picea abies /L./ Karst.) is the most endangered species. The year timber supply decrease of this species is supposed in an extent of 0.9 mil.m3 in the next two decades (2013 – 2032) and more than 1 mil. m3 for all conifers. Cultivation of Douglas-fir (Pseudotsuga menziesii /Mirb./ Franco) can substitute N. spruce on specific sites and so eliminate partially the timber supply decline in the future. The cultivation of Douglas-fir could lead to increase of the plantation area from 5,800 ha (today) to the extent of 49,616 – 163,713 ha respecting legislative restrictions and recommendations of general management plans. This can represent increased timber increment of 300,000 – 650,000 m3 per year and substantially mitigate the coniferous timber supply fall in the next decades.

Impact of silvicultural measures on the quality of Scots pine wood. Part I. effect of regeneration method

This study deals with the influence of the silvicultural measures on selected mechanical properties of Scots pine (Pinus sylvestris L.) wood in the Czech Republic. Sample trees were selected at two different localities that are characteristic of Scots pine growth, and they represent two different Scots pine regeneration methods, namely the clear-cutting and shelterwood regeneration method. We tested compressive strength and impact bending strength. The density of the wood was also evaluated as a factor influencing strength characteristics. The shelterwood regeneration method shows higher values in most of the investigated characteristics (49.3 MPa for the shelterwood method and 44.6 MPa for the clear-cutting method in the case of compressive strength); however, these differences are not significant for the processing industry. Another positive effect of the shelterwood regeneration method is the even distribution of the properties within the trunk in radial direction in contrast to clear-cutting method.