Fig. 2
From: Single-tree crown shape and crown volume models for Pinus nigra J. F. Arnold in central Italy
Estimated single-tree crown volumes for trees between 2 (top-left) and 16 (bottom-right) meters of crown length. The proportion of volume for lower (skyblue) and upper (green) portion of the crown is reported with different colour. The height of the green bar already represents the sum of them. Each bar of each single plot corresponds to a calculation performed with a fixed height but a variable average crown diameter between 0.25Â m (first bar, left) and 5 (last bar, right) meters assumed to be the maximum radius a Pinus nigra tree can achieve at maturity. Volumes on y-axis are reported in m3