Ключевые слова: action, calendar, chain, chainsaw, chip, cortex, cross section, damage, danger, dead, destruction, ecological, ecological problem, ecology, energy, environmental, forester, forestry, green, hardwood, horizontal, industry, job, lumber, machine, material, natural, nature concept, old tree, pile, pine, power, protection, protective, raw material, ring, rough, saw, sustainability, texture, timber, tool, tree, trees, trunk, wood, woodland, work, worker,