Abstract
As the focus in forestry is moving from timber production to prioritized economic benefits and better integration of ecological-social functions, practical forest management is shifting towards promoting diverse stand structures. Promoting stand structural heterogeneity requires accurate and profound evaluations of spatial stand structure that are generally not provided during conventional forest inventories. In this paper, different indices describing the heterogeneity of the stand and the spatial arrangement of trees, including their size, condition and species were assessed. Indices were applied to the inventory data collected from the Estonian Network of Forest Research Plots. The results show that the studied structural indices are useful in assessment of Estonian forest stands. The practical importance of structural indices will increase in future as there will be a need for methods for characterizing forest stand structural diversity at a large scale, for example, derived from high-resolution remote sensing data.