Is height of dominant trees at a reference diameter an adequate measure of site quality?

Abstract

Based on ecological and stem analysis data obtained from white spruce-dominated stands in the Sub-boreal Spruce of British Columbia, the validity of using height of dominant trees at a specific breast height diameter (20 cm) as an index of site quality was tested. The results indicated that (1) height of dominant trees at 20-cm breast height diameter was related neither to site index (height of dominant trees at 50-year breast height age) nor to ecological measure of site quality (i.e. soil moisture nutrient regimes); (2) taper (diameter : height ratio) did not decrease with increasing site quality; and (3) stand density might have influence height–diameter relationships of dominant trees. Therefore, we conclude that height of dominant trees at a specific diameter is not an adequate measure of site quality.