A New Stocking Guide Formulation Applied to Eastern White Pine

A procedure is described for incorporating stand age, or stage in development, into the widely used stocking guides based on the crown competition factor (CCF). A simple model that predicts dbh of individual trees from crown projection area and total height is derived from a three-dimensional relationship between cumulative foliage production (crown volume) and total volume of the main stem. Procedures employed by previous researchers to prepare CCF-based stocking guides are then used to convert this individual-tree model to stand basal areas and numbers of trees per unit area at successive stages in development denoted by stand heights. An equation relating crown width to crown length and height is derived and used to predict growth under conventional and low-density thinning schedules for eastern white pine. An example shows that complete crown closure can occur well below the CCF-based B level if early thinnings are heavy enough to permit development of large crowns. Because CCF-based stocking guides assume that the crown width-dbh relationship is independent of height, they may, in some cases, overestimate the number of trees required for full crown closure. FOR. ScI. 33(2):469-484. ADDITIONAL