The article presents the method of estimating the stand stability and the results of its practical application. The index of global stand stability is calculated by averaging the partial stability values belonging to the selected stand attributes. The selection of the attributes has been made separately for the following stand developmental stages: young stand, thicket, middle-aged stand and mature stand. The main attributes influencing the stability of the tree stand are forest sites, tree species composition, type of stand establishment and stand tending effects (stand density, diameter structure, H/D ratio). The method has been tested in the Lipce Forest (experimental forest of Warsaw Agricultural University in Rogów) including 245 stands covering 885.35 ha. The results of the test show that around 2/3 of stands (mainly young stands and mature stands) are stable (state 1) and satisfactorily stable (state 2). The rest of the stands (mainly thickets and middle-aged stands) are threatened by instability – 28% (state 3) or are already instable – 5% (state 4).

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