Ключевые слова: alternative energy, at the bottom of, backgrounds, beech tree, biomass ecological concept, biomass renewable energy source, branch, brown, business finance and industry, closeup, construction material, cross section, deforestation, destruction, environment, environmental damage, fallen tree, firewood, forest, fuel and power generation, green color, hardwood, heap, industry, log, lumber industry, material, nature, no people, outdoors, pattern, pinaceae, pine tree, plant, plant bark, rural scene, sawing, social issues, stack, sustainable resources, timber, tree, tree area, tree trunk, vitality, wood material, woodland, woodpile, working,