Crown Position and Light Exposure Classification-An Alternative to Field-Assigned Crown Class

Crown class, an ordinal tree-level mensuration attribute used extensively by foresters, is di#icult to ass ign in thefield because def ini t ions of individual classes are confounded by ambiguous references to the position the tree in the canopy and amount of light received by its crown. When crown class is decomposed into its two elements-crown position and crown light exposure--field assignments are more repeatable, and crown class can be assigned by algorithm with the same degree of accuracy that it can be est imated in thef ie ld . Replacing tradi t ional crown class wi th the twoproposedal ternat ive variables y ie lds more speci f ic in format ion about each tree . Crown posi t ion and crown l ight exposure add in format ion potent ia l ly useful for modeling and other applicat ions. North. J . Appl . For. 20(4):154-160.