Fig. 5From: Degradation and restoration of Indigenous California black oak (Quercus kelloggii) stands in the northern Sierra NevadaViolin plots of regional historical (1924, left) and contemporary (2011–2018, right) distributions of relative stand density index (% of maximum SDI) including all trees ≥30.5 cm DBH. The gradient of gray shaded boxes indicates SDI benchmarks for free competition (in white; ≤25%), partial competition (25–35%), full site occupancy (35–60%), and imminent mortality (≥60%). The solid black line indicates 100% of the maximum SDI (902 trees ha−1; 365 trees ac−1)Back to article page