Abstract
The study discusses two approaches to predict e effect the effect of neighboring trees on the 5‐year basal area growth of Scots pine. The first approach relies on empirical competition indices and the second on an ecological field theory. The growth models account for 82–84% of the within‐stand variation in basal area growth. The directional distribution of competitors has a slight influence on the tree growth, besides the number, size and distance of the neighbors. To demonstrate the use of spatial growth models, three simulation studies are presented. The first one examined the effect of the spatial pattern of trees on the volume increment of the stand, the second one the usability of variation in the stand basal area as a measure of grouping, and the third one the effects of harvest roads.