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Harvested timber has many various wood defects. Analyses were carried out on material collected in Zaporowo Forest District (northern Poland). Results show that various defects were found in 35% of harvested timber on average. The share of timber with defects varied among individual species (pine – 44%, spruce – 22%, oak – 14%, birch – 9%, beech – 5%, lime and larch – 2% each, hornbeam and alder – 1% each). The individual wood defects appeared in harvested timber with following frequency: knots – 55%, knobs – 22%, foreign bodies – 7%, curvature – 5%, inner rot – 5%, galls – 2%, blue stain – 1%, insect holes – 1%, false heartwood – 1%, and cracks – 1%. Timber defects resulted in reduction of income from the sales. A decrease in income caused by various defects amounted from 0.07 PLN/m³ for brown sap stain to 68.83 PLN/m³ for knots. The greatest effect of wood defects on the reduction of income from sales was recorded for oak timber (518.30 PLN/m³), while the smallest for aspen (4.63 PLN/m³). Due to the fact that in almost all analysed tree species the dominant effect on the reduction of income from timber sales was caused by knots (open knots and knobs) systematic solutions need to be found in order to reduce the effect of this defect. It is particularly important in the case of oak timber, where a decrease in income from timber sales connected with this defect was the greatest.
The qualitative and dimensional variability of wood material affects its possible uses for industrial purposes. Attempts to order the rules of raw material classification contributed to the introduction of qualitative and dimensional standards approved by the Polish Committee for Standardization. Large−size softwood is the main raw timber material in Poland. The adjustment of requirements and rules of raw material sorting to changing market needs was caused by the necessity of prompt reaction to technological changes. Although standards were adjusted to the EU requirements, the State Forests National Forest Holding creates the rules of large−size wood classification through the corporation legal acts – the ordinances of the General Director. The article presents the beginning of the process of large−size softwood trade standardization in Poland. It indicates the rationality of meeting the requirements of qualitative, dimensional and purpose−related classification in the era of rapid changes in the demand of the industry. After the rebirth of the Polish state, there were attempts to improve rational use of wood. This goal was achieved by introduction of the rules of assortment classification for available forms of material. Verification of wood structure defects and properties in selection of large−size assortments resulted in consecutive amendments facilitating the procedures of selection of adequate quality and thickness classes in large−size wood. This enabled gradual adjustment of assortment classification to the needs of the wood industry, which is the recipient of wood material. Due to the increasing dynamics of changes it was necessary to develop new forms of wood division and classification. The role of product standards was gradually taken over by technical conditions developed by the State Forests, which is in charge of major material resources in Poland. This form of verification of the principles of wood division and classification guarantees prompt adjustment to the needs of clients on the wood market, which are changing at an increasing rate.
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The paper analyses the amount of cut, the assortment and species structure of the current domestic market for timber of the highest quality classes (wood veneer, plywood, telecommunication poles) in Poland in years 2005−2009. Oak and beech are the main source of material for the production of veneer in Poland. Sales of oak veneer in 2005−2009 amounted to 17,502.9 m3 (35.8% of the total sales of assortment WA1). Sales of beech veneer in 2005−2009 amounted to 11,233.5 m3 (23.0% of total sales). Among the plywood assortments harvested in Poland in 2005−2009, birch was harvested and sold in the largest quantities – 503,870.0 m3 (39.1% of total harvest) and 590,822.4 m3 (43.8% of total sales). Of all the regional directorates of the State Forests, the Krosno RDSF showed in 2005−2009 the largest harvest of WA1 assortments – 9734.0 m3 (21.4% of the total harvest), and sale – 9611.0 m3 (19.7% of total sales). Because of the large beech and sycamore timber resources, forests in the Krosno RDSF are a main current and potential source of veneer assortments. Because of the large amounts of harvested and sold oak, beech, pine, birch and alder veneer the Białystok, Olsztyn, Szczecinek and Szczecin RDSFs play the dominant role on the Polish timber market. The leading role in terms of plywood sales in the period under review was taken by RDSFs Olsztyn – 24.9%, Białystok – 26.2%, Szczecinek – 13.1% and Szczecin – 11.6%. These RDSFs taken together supplied to the market 75.8% of plywood, being the main material base for the plywood industry. The dominant role of these RDSFs derives from the fact that forests under their administration are rich in birch, alder and pine. Spruce as a plywood material is insufficiently used by the plywood industry (harvest – 33,269.9 m3, sale – 579.5 m3).
Scots pine wood is widely used in many branches of the wood industry. The possibility to select the raw material quality according to the specific processing needs corresponding to different uses is related with the issues of the standardisation, which comprises classification based both on the dimensions of processed assortments as well as their defects and traits of anatomical construction. In the last two decades of economic transformations in Poland, there has been increasing importance of the standardisation process because of the trade between the European Union (EU) member−states. EU−membership involved gradual adjustment to the rules of round wood trade, which are applicable in the old EU member−states. Many international certification institutions as well as the Polish Committee for Standardisation were involved in the process of standardisation. The experience of northern and western European countries generated a very complex classification system, which partly matched the national standards. There are differences in the description of Scots pine wood characteristics and defects in the domestic standards and technical conditions concerning this timber trade, which is of key importance to the Polish wood industry.
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Analiza efektywności wywozu drewna

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Analizie podano podstawowe wskaźniki techniczno-ekonomiczne dwóch samochodów do wywozu drewna. Określono wydajność oraz bezpośrednie jednostkowe koszty wywozu.
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