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Oak (Quercus robur L.) forest stands are among the most common forest formations in the forest-steppe zone of Ukraine. Investigations of the patterns of distribution of trees by diameter and the dynamics of the commodity structure of mature oak stands of coppice origin were carried out based on the forest survey data from 28 temporary sample plots, on the sites designated for the final felling in the Left-Bank Forest Steppe of Ukraine (Sumy, Kharkiv, and Poltava Regions). We distributed trees by diameter classes and technical suitability categories. To establish the commodity structure of the stand, we selected model trees that corresponded to the average size of trees in terms of diameter classes and their qualitative characteristics. Then, we constructed a model tree stem profile using Institute of Forest Ecosystems Research (IFER)’s method of “6 points”. Based on stands’ structure and quality condition as well as on the growth tables, the commodity structure dynamics table for the changes in the commodity structure for the coppice oak stands in the Left-Bank Forest Steppe of Ukraine has been developed. The results of the analysis of wood stock dynamics showed that the maximum average increment of class A and B wood is 90–100 years. Therefore, the age of technical maturity and the associated age for the final felling in commercial oak forests of second site class and above should be assigned to 91–100 years.

In the last decades different methods have been developed for measuring piled wood, i.e. wood stacks. There are two main groups of measurements: the first one is manual methods and the second one is automatic measurements. Taking into consideration the amount and market value of stacked wood, the accuracy of applied measurement is of high importance, as the price is calculated according to the measured amount of wood. Manual measurements are mostly time consuming and dependent on individual performance. On the other hand, the automatic methods are fast and their accuracy has increased in the last years. They allow to obtain relevant results when calculating prices at different locations, independent of the measurement time. These methods range from simple manual measurements using a tape to photo-optical measurement systems. Also, other measurement methods (e. g. water immersion) are currently used in practice. The paper describes the individual manual and automatic measurement methods for industrial timber and their working principles. Furthermore, the advantages and disadvantages related with the requirements and accuracy of the individual procedures have been explained and their practical use discussed.

Concerning industrial timber, the measure of stacked logs with equal wood length is cubic meter with bark (FVA 1997). It is consequently a volumetric measure including the non wood-containing spaces. The following work determines by extensive tests the solid measure of several stacks of wood by the means of an electronically measuring system, and calculates the resulting conversion factor. It was possible to make a statement about how the mid-diameter of logs from a stack and particularly log-parameters influences the conversion factor. The measurements in 3D, the mid-diameter, the crook, the taper and the ovality are considered and their influence on the factor were analysed. The results are illustrated and evaluated by using a correlation and regression analysis. The greater influence had the mid-diameter and the crook, which show strong correlations on the factor.

In forestry, alien tree species are planted to maximize yield from a stand by increasing productivity and decreasing environmental risks. In Eastern Europe, lodgepole pine (Pinus contorta var. latifolia) might be used as a source of biomass and industrial wood; however, before any recommendations are given, possible gains of the novel species should be scrupulously evaluated. In this study, we compared volume and proportion of knotty stemwood (VKN) of native Scots pine (Pinus sylvestris) from first generation seed orchards and provenances of alien lodgepole pine [Fort Nelson (58°38' N, 122°41' W) and Summit Lake (54°24› N, 122°37› W)] at the age of 27 years growing in central Latvia. We also assessed the relationships between VKN and several morphometric parameters. Stem diameter of both species was similar; however, Summit Lake provenance of lodgepole pine exceeded Scots pine in height, while Fort Nelson provenance was lower than Scots pine. Although Scots pine produced nearly two times less whorls than lodgepole pine, volume of knotless stemwood did not differ significantly between the species; though it was higher for Summit Lake provenance of lodgepole pine compared to Scots pine. In contrast, the proportion of VKN differed significantly between both the species and the provenances. Scots pine showed the lowest proportion of VKN (~ 9%) and Fort Nelson provenances of lodgepole pine showed the highest proportion of VKN (~ 14%). Thus, Summit Lake appears more suitable for the production of industrial wood amongst the provenances of lodgepole pine; nevertheless, higher quantity of leftover material is expected. Some morphometric parameters correlated with VKN and the proportion of VKN, but these relationships differed between species and provenances. The total cross-section of branches was the best predictors of VKN for Scots pine and Fort Nelson provenance of lodgepole pine, while stem diameter showed the strongest correlation for Summit Lake provenance. Number of whorls and mean diameter of living branches were the best predictors of the proportion of VKN for lodgepole pine and Scots pine, respectively. Accordingly, morphometric parameters might be useful for the selection of the best trees of lodgepole pine. [ABSTRACT FROM AUTHOR]

Concerning industrial timber, the measure of stacked logs with equal wood length is cubic meter with bark (FVA 1997). It is consequently a volumetric measure including the non wood-containing spaces. The following work determines by extensive tests the solid measure of several stacks of wood by the means of an electronically measuring system, and calculates the resulting conversion factor. It was possible to make a statement about how the mid-diameter of logs from a stack and particularly log-parameters influences the conversion factor. The measurements in 3D, the mid-diameter, the crook, the taper and the ovality are considered and their influence on the factor were analysed. The results are illustrated and evaluated by using a correlation and regression analysis. The greater influence had the mid-diameter and the crook, which show strong correlations on the factor. [ABSTRACT FROM AUTHOR]