View article

Projection of stand development over time relies on accurate height–diameter functions. In complex forests where trees of various ages, species, sizes, vigor and crown classes, and shade tolerance levels co-exist, tree height predictions are more difficult than in uniform conditions. In such complex situations, individual tree height–diameter relationships and predictions are often further complicated by structure (e.g., relative position of trees) and stand density which sometime are exacerbated by selective harvesting and other disturbances, and changing stand dynamics. Height–diameter (H–D) relationships are significantly modulated by microsite (elevation, aspect and slope), climate, and competition. Traditionally, tree height–diameter relationships are modeled or examined using linear or nonlinear regression models, in which the microsite influences or species–habitat relationships are largely ignored. Studies …