Development of reference materials for assessment of dynamics of biometric parameters of modal stands is an important component of research of forests’ productivity. In this research, on basis of a stand-level database of IA “Ukrderzhlisproekt” we have statistically justified allocation of pure and mixed stands for hardwood broadleaved tree species by means of cluster analysis and graphical comparison of dendrograms of cluster objects for the main biometric indices (mean height, mean diameter and growing stock per 1 ha). The results prove that for the majority of factors stands with 9 out of 10 units of a certain species in composition belong to the same cluster as those with 3 to 8 units. This has enabled us to allocate pure stands as those featuring 10 units of a certain species in composition. The next stage was to test the null hypothesis on the significance of the difference between the mean values of the main biometric indices of the stand groups allocated from the stand-level database. The groups included pure and mixed stands, stands of natural and artificial, seed and vegetative origin. The statistical toolbox applied includes the Student’s t-test and Fisher’s F-test. As a result, after an analysis of the calculated indices, considering the structure of the stands in question in terms of their species composition and origin, we have allocated 6 groups for oak, 2 – for beech, 3 – for hornbeam and 3 – for ash stands. Further research of growth and productivity of the hardwood broadleaves linked with the development of yield tables for modal stands should be based on the allocated groups and dynamic site index scales.
composition of a stand, origin of a stand, cluster analysis, biometric indices, Student’s t-test, Fisher’s F-test