The new metrics we calculated is the stochastic dominance index (SDI) given by the squared ratio between the area under cumulative distribution function (CDF) of high-quality trees and the area under the CDF of low-quality trees. SDIs were calculated separately for trees volume and diameter for beech, durmast, and oak trees. The procedure was applied on a set of data collected from 2592 harvestable trees within 35 compartments. where all trees had been grouped in two quality classes: high quality and low quality respectively. We considered three combinations of SDIs that hint to three different decisions: 1) if both SDIs < 1 it is recommended to spare low quality trees as deadwood; 2) if both SDIs > 1 it is preferable to put off harvesting operations for one decade, in order to increase the volume accumulated on high quality trees, and 3) if the two SDIs convey confusing signals, the whole stand shall be harvested in due time, or even sooner, if needed. It was found that only 3 compartments, stretching over 57 hectares, could be entirely spared from harvesting in order to keep low quality trees as habitat for fungi, insects, birds, and small mammals.