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The study compared basic density, compressive strength along the grain, static bending strength and modulus of elasticity of juvenile wood in pines from different Kraft’s classes. Analyses were conducted in 8 mature pine monocultures in north-western Poland. In each experimental site a total of 9 trees were selected, thus the analyses were conducted on 72 model trees (with 24 for each social class of tree position in the stand). The highest values of analysed technical parameters were recorded for wood of co-dominant trees, the lowest were found for predominant trees, while intermediate values were recorded for wood of dominant trees. All the reported differences were statistically significant. Similar dependencies were observed when comparing wood from different sections of stems, with the greatest disproportions, frequently statistically significant, found in their lower sections.
The studies covered the population of 87 Polish cold-blooded stallions subjected to performance tests during the years 1999-2005 in northeastern Poland. The analyzed group of breeding stallions was divided into two groups considering the ownership sector. The detailed analysis covered the influence of biometric parameters and bonitation of stallions on the results of performance tests (initial and main part). During the covered years an increase in values of basic biometric parameters of stallions subjected to field draught tests was found and the average withers height of private stallions was statistically much lower than in case of State-owned breeding stallions. The results of initial performance tests indicate good preparation of stallions from both ownership sectors for them while the results of main tests are more diversified and indicate better preparation of stallions from Stallion Depot in Kętrzyn. Dependence between the values of basic zoometric parameters of breeding stallions and the results of performance tests was shown in both analyzed ownership sectors. This indicates a link between horse built and its utility predispositions. The qualitative distribution of studied material in both ownership sectors was significant for results of performance tests. A significant dependence between the bonitation points; score and the results of both the initial and the main test has been shown.
In the course of the performed investigations, an attempt was made to analyse the radial shrinkage variability of Scots pine (Pinus sylvestris L.) wood in relation to the biosocial position of trees occupied in the stand. The performed experiments employed the wood of pine trees grown in conditions of the fresh coniferous (Bśw) forest site type and mixed fresh coniferous (BMśw) forest site type, which represented the main stand, i.e. the first three classes of the Kraft classification. The maximum shrinkage value changed depending on the forest site type and tree biosocial position. The strongest differences in the maximal values of wood shrinkage between trees derived from conditions of the Bśw and BMśw for all the analysed Kraft classes were observed for the radial shrinkage.
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