A Critical Evaluation of Old-Growth Forest Definitions in Canada

Abstract

Old-growth forests are a precious resource. As critical areas of biodiversity, they provide habitat for many species at risk. They also provide a multitude of ecosystem services and have enormous intrinsic biological value and aesthetic appeal. In order to properly conserve these forests for future generations, it is important that they can be appropriately identified. Canada has substantial old-growth forest areas in multiple provinces, the regulation of which falls under provincial jurisdiction. A series of different old-growth forest definitions have therefore been developed. The purpose of this study was to perform a critical analysis of the existing operational definitions of old-growth forest, focused on the commonality and utility of their key characteristics. This study evaluated selected definition-characteristic frequency of use and utility across provincial jurisdictions with publicly available operational definitions of old-growth forest. This study aimed to address the knowledge gaps that exist surrounding the format and quality of different old-growth provincial and territorial old growth forest definitions to help inform the future development of old-growth forest definitions. The results of our study showed that half of Canada’s provinces had no official, publicly available definition of old-growth forest, or had only a conceptual definition. Only six provinces - Newfoundland and Labrador, Nova Scotia, New Brunswick, Ontario, Saskatchewan and British Columbia - were found to have an official operational definition of old-growth forest. Each of these provinces took a different approach, using different combinations of definition characteristics and format. Ontario’s old-growth definition included the greatest proportion of high-utility definition characteristics. We used the information obtained to develop a template definition for characteristics that might be included into new old-growth definitions. This incorporated high-utility definition characteristics from existing definitions and new old-growth assessment techniques such as the use of indicator lichens.