The development of Picea abies in Denmark illustrated with 60-year trajectories from stands thinned to four prescriptions (A, B, D, L). The A treatment (lowest line) had 3 thinnings progressively reducing density from 5428 to 2017 stems· ha− 1. The L treatment (uppermost line) reduced density from 733 to 126 stems· ha− 1 gradually in 14 thinnings. Grey-filled points indicate stocking < 150 stems· ha− 1. Data courtesy of Prof J.P. Skovsgaard, Danish Centre for Forest, Landscape and Planning.