Modelling numerical thinnings in forest management

This paper describes the construction of a simulation model for intensive management of even-aged stands of spruce (Picea abies Karst.) in Belgium. A computer program produces a thinning schedule or a guide to reduction in number of trees. Knowing the total production of which a site is capable, the forester may calcultate how many trees growing at a chosen rate are required to use the capacity of this site. The model starts from stand constraints issued from inventories (age, number of stems, top height, mean diameter) and silvicultural constraints (annual diameter increment, rotation age, thinning cycle and thinning type).