The aim of the study is to generate yield tables that enables calculating the stumpage values of the forests in different ages. The article investigates the diameter distribution of a stand at the breast height and their changes with the age of the stand. In an even-aged stand the calculating of the stumpage value is based on height and breast height diameter. Hence the diameter distribution of a stand determines the stand volume, the stem frequency distribution series can be used as the basis of compiling the yield tables, in which the volume is the main factor.
The study is based on spruce and pine mensuration data from Finland, pine stands from Prussia, and spruce stands from mountainous area of Switzerland. The article presents the characteristics of stem frequency distribution series based on the data. The studied characteristics are arithmetic middle, dispersion, asymmetry (skewness) and excess.
It can be recommended to create tables that show the different developments for age classes. Based on such tables the expected value of the stand can be calculated in practical forest management. Determining a general value of a stand in different forest site types would be important for forest valuation and forest statistics.