Malinen, J., Piira, T., Kilpeläinen, H., Wall,T. and Verkasalo, E. 2010. Timber Assortment Recovery Models for Southern Finland.  Baltic Forestry 16 (1): 102-112

Along with the total volume harvested, the recovery of timber assortments defines the suitability of the marked stands for different uses of wood. The recovery of the different assortments impacts, to a great extent, the sale value of the stand for the forest owner as well as on the processing value for the wood buyers. In this paper, models to predict the timber assortment recoveries of Scots pine and Norway spruce in clear-cutting stands in southern Finland are presented concerning the application of different bucking instructions for the targeted timber assortments, and for the allowed log dimensions. The material consisted of empirical data from 124 stands in southern Finland collected from circular sample plots. The timber recoveries, when using different timber assortment combinations, were modelled as separate model chains. The potential predictor variables were required to be easily measurable within the limits of capabilities by the forest owner or by the wood buyer. Stand characteristics used as potential predictor variables included variables depicting site fertility, tree species composition, stand volume, and stem size distribution. Furthermore, concerning the options to cut each assortment, the minimum log lengths and top diameters were used as potential predictor variables describing the bucking instructions applied.

Key words: assortment recovery, modelling, bucking simulation