The students learn about the physical, mechanical and chemical properties of wood, the variability and differences among different species. They can recognize wood defects on standing trees and harvested stems and grade wood assortments. Finally, they can choose the correct species for further usage according to its properties.
Course Content (Syllabus)
Natural, macroscopic characteristics and identification of basic wood species. Transverse, radial, and tangential surface. Physical characteristics of wood: Color, gloss, odor, taste, texture, design, weight, hardness.
Microscopic structure: Wood tissues, cell walls and cavities, intercellular layer, pits. Description of cell types of coniferous and deciduous species. Intercellular spaces and ducts.
Chemical composition and infrastructure of wood: inorganic components, organic components and extractives. Microfiber structure and basic theories related to wood infrastructure. Cell wall structure, pits, warty layer. Distribution of chemical components in the cell walls of wood and effects on its properties and uses.
Wood production mechanism: Production of new wood cells. Importance and action of the cambium. Evolution stages of wood cells. Variability and structural defects. Horizontal and vertical variability. Heartwood formation. Immature, mature and overripe wood. Growing rings. Variability between trees. Structural defects. Deviations a) the formal external form b) the responsibility. irregular structure of growth rings. Compressed and tensile wood. Tissue discontinuations, color abnormalities, knots and pith.
Density: Factors affecting it, density variability, determination and importance. Hygroscopicity: Ways of retaining moisture in the wood, adsorption - desorption. Equilibrium moisture-content. Fiber saturation point. Determination and importance of the hygroscopicity of wood. Wood shrinkage and swelling. Identification and their importance. Mechanical, thermal, electrical and acoustic properties. Factors that affect them and their identification.
Degradation of natural wood.