Attrition is referred to trees, which died as a result of natural density decrease. The article is devoted to studying dynamics of number and stock attrition in spruce stands in Moscow Region. This work used the results of the research that has been carried out by Forest Inventory and Protection Department, MSFU, on 6 permanent plots starting from 1954. Distribution character of number and stock attrition on natural diameter classes, change of attrition intensity and dependence of percentage of the annual tree number attrition and stock attrition on the age of stands were revealed in the given forest stands. Variation of the tree number and stock attrition on natural diameter classes and age statistically was similar. Models were developed for predicting number and stock attrition.
