An interesting debate is currently running here, (at least I'm interested :-), but I wonder I we have the ground established anywhere? I don't think the argument is really about *exotic*, because, as David South pointed out, we are *exotic*, and unless you believe in the creation of a fully formed universe, with everything in its proper place, everything is *exotic* All species have migrated or evolved to an appropriate niche. The argument could be against those species that were brought by (selected races of?) mankind Vs those that arrived by other means...but I don't think that is useful. For example, the dingo is exotic to Australia if its ancestors were carried over by the aboriginals, or they are natural if their ancestors swam or were blown over on a log by a passing hurricane. What if they stowed away on a large canoe - are they exotic or not ... who cares! What about declaring exotics as species that haven't been in a locality for at least X years? How big do we make X? And does that mean that all species were exotics at one point, but given enough time, they will not be at some other point? Rabbits in Australia therefore were an exotic, but because we have never been successful in erradicating them, they will one day (depending on X) become native!? Again, does it really matter? The argument really is, if humans want to plant and manage tree species, what is the best planting and management possible. And if humans decide to do this, they do make the decision to "Mess with Mother Nature" as David Orr puts it. In fact, every time humans make a decision (including not to act), they will be messing with nature - the only choice is which mess! Having made that decision, the argument really appears to be one of monoculture or not, and intensity of management. Most of the arguments in the current thread seem to be arguing against monoculture and/or intensive management on the one hand, and the value of well managed plantations on the other hand. Ryde James pointed this out - you must evaluate the costs and benefits of each option and then judge what you are going to do. If you plant a plantation, of whatever species or mix of species, you have to ensure that you are being as efficient and as effective as possible in your management - ie don't waste time, land and resources that could be better managed. You have to include dealing with all the costs, including escape management - and *native* species (ie native to the country but not the plantation) would be more likely to escape than exotics. Monocultures have an undefined risk of catastrophic disease etc, the managers must consider that risk, etc. The speed and quality of growth, other incidental products (eg honey production), and the attractiveness of the *factory* (ie the plantation) will define your benefits - they too must all be considered. Leave simple arguments like "exotics are bad" to the xenophobes! Personally, I'd like to see a mixed species, low intensity management of an unevened-aged forest ... you know something like *native forest management* But that would only be economically possible IF there were no start-up costs, for example, we could manage native forests - and then there wouldn't be a problem of exotics! Alternatively, replace the current plantation of intensively managed monocultures (eg wheat, cities) with tree monocultures...that would result in less cost to "Mother Nature" Have fun! Cris. Cris Brack, Lecturer, Forestry Australian National University, 0200, A.C.T. Australia. Phone : +61 6 249 3535 (work) +61 6 258 7478 (home) FAX : +61 6 249 0746
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