Abstract
An ecological understanding of old-growth requires a multiscale perspective, ranging from individual trees to regions. A consensus on a single general ecological definition of old-growth will never be reached, but that should not preclude the development of specific definitions needed by managers. Old-growth forests share many attributes, such as spatial heterogeneity, but they also differ in many ways. Given the complexity and dynamics of forests, efforts to conserve biodiversity must be sensitive to the diversity of old-growth forests and must consider forests of all developmental stages, not just old-growth. One implication is that forest policies and management practices may need to be as diverse as the old-growth forests they address.