Table 1. Structural indicators of old growth Stand density (e.g., number of trees, basal area, or stand density index) Spatial distribution of old trees (clumped or random) Species composition Live crown ratio Diameter class distribution Age class distribution Age of oldest trees Number of canopy layers Canopy cover Snag density (number of dead trees) Dead and downed logs (number or volume of downed logs) Amount of dead or broken tops/boles