“…In 1955-56, after an inventory of the forest had been carried out (Carron 1955), fifty fifth-acre plots were established as a stratified random sample within 1,000 acres then over 12 years of age, this being about the first age when site index can be determined with any confidence and when thinning will provide a worthwhile volume. These plots have been remeasured twice and have provided data for a variable-density yield table the compilation of which is now described.…”