Jenny, If you use a too restrictive definition of old growth, there will no forests in eastern United States. Virtually all of them have been disturbed to some degree or another. People making definitions tend to define the term in a way that best serves their own interests. Timber industries, and people who want to cut an area use a really restrictive definition so that they can say whatever they want to cut is not old growth. I think environmentalists do the same, but overall use definitions that are more fair than those in favor of "utilization." Any definition has to be made in the context of other forest in the area. There can be no one size fits all, as each forest, and each region is different. Any definition that uses specific age criteria will almost assuredly exclude forests that should be considered old growth.
There has been extensive discussion of the definition of old growth on the ENTS list. http://www.nativetreesociety.org/oldgrowth/index_oldgrowth.htm I wrote the introduction and it gives an overview of the question. There is a nice pamphlet on the characteristics of old growth here: http://www.lrconline.com/Extension_Notes_English/pdf/oldgwth.pdf In Sept 2006 I posted the following old growth definition as a starting point for debate: The primary characteristic of an Old-Growth forest is that it contains a substantial percentage of old trees in a setting that exhibits only limited human impact. These forests are generally characterized as late-successional or climax forests for a particular regional or environmental regime. Canopy openings formed by natural processes, such as wind throw and fire, and populated by younger trees are often found contained within the larger old-growth forest. Another forest classification system defines Primary or Natural Heritage forests as "forest with a continuous heritage of natural disturbance and regeneration." (Frelich and Reich, 2003). The sets of trees and forests encompassed by each definition overlap in part, but are not completely congruous. It certainly was not overwhelmingly approved without reservation, but think it is a workable definition to start with when looking at a particular forest or forest segment. The key in my mind is that an old growth forest needs to be defined in the context of other forests in the area and regions, so in a sense the best old growth forest in an area is the one that has suffered the least major human disturbance - logging, clear cutting, and farming. It may not be perfect but... Ed Frank --~--~---------~--~----~------------~-------~--~----~ Eastern Native Tree Society http://www.nativetreesociety.org Send email to [email protected] Visit this group at http://groups.google.com/group/entstrees?hl=en To unsubscribe send email to [email protected] -~----------~----~----~----~------~----~------~--~---
