[Time studies of two delivery methods of chips to heating plants: Chips and roundwood of young spruce]

abattage d'arbres aclareo astillas bois de chauffage bois rond corta danemark denmark dinamarca estudio del trabajo felling forest litter forestry operations fuelwood gestion des ressources handling handling machinery hojarasca forestal horas laborables madera en rollo manutention operaciones forestales particule de bois production costs production forests resource management road transport roundwood temps de travail thinning transport routier transporte por carretera wood chips woodworking equipment work study working hours