Jenny, Under natural conditions many of the meadows and prairies would not turn into forest for thousands of years. Now the natural systems of flooding, fire, etc have been so disrupted the processes that maintained the grasslands in many cases no longer operate. In places like Jennings they use annual mowing to keep down the woody shrubs and trees that might take over in the absence of frequent fires. Other areas the ground was under cultivation or developed and the structure of the soil itself, the natural drainage systems, and related factors have all been irrevocably changed. I am not sure about restoring natural grasslands. In the Allegheny River System there are grasslands on some of the islands, but with the annual floods of the river controlled by Kinzua Dam, the natural flood mediated grasslands have been replaced by masses of invasive Reed Canary Grass and the areas are being encroached upon by hawthorn bushes and trees. They seem to one of the few native species able to compete well with the canary grass. With a return to serious flooding they might return to more native flood tolerant (and dependant) grasses, but short of that I can't think of how they might be artificially restored or maintained. There likely are people who know about restoration of grasslands, just not me.
Should we create meadows by cutting down trees? What should be the priorities for management - should ecosystems most threatened by species extinction take precedence? I believe we should be trying to maintain or expand areas of certain ecosystems in order preserve species threatened by extinction. But this is a special case that applies only with threatened or endangered species. On a more general scale we should be preserving uncommon ecosystems and relatively intact ecosystems to create diversity on a broad landscape scale whether they contain threatened or endangered species or not. The uncommon ecosystems or partial ecosystems are important. Old Growth forests are an example In them the diversity of large charismatic bird and mammals species may be lower than in a forest edge/meadow community. But they need to be preserved because the birds, mammals, and other species found there, are often found only in these old growth areas. You might increase some aspects of species diversity on a smaller scale by cutting these old growth forests, but on a broader scale you would be losing those species that require the old growth. In cutting them you would be losing diversity overall. Broad scale versus local scale considerations need to be made, much like there needs to be long term planning to maintain a resource rather than just going for short term gain. I guess if the question is should we be cutting down trees to make meadows - I would favor it only if it was returning it to a natural system that had existed there previously could be maintained as such over a long term. You might also try to reclaim heavily impacted land and turn it into a meadow or prairie if it were appropriate to the area. But I am not sure if it could even be done, because under normal conditions the land in the east will typically revert back to forest. Prairies only form under special circumstances. people have tried to make artificial wetlands with mixed success. Perhaps.... Ed --~--~---------~--~----~------------~-------~--~----~ 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] -~----------~----~----~----~------~----~------~--~---
