Rob Bennett proposes establishing a number of eastern hardwoods in southern British Columbia, and enquires about seed sources. My primary response to this proposal and others like it is "Why?" There are so many examples of plantations of non-indigenous species having unforseen negative effects, that one really has to question their adviseability anywhere. I can think of the following possible reasons for exotics: Are they (here, sugar maple and white ash) expected to out-perform native species? (highly unlikely they would outgrow red alder and black cottonwood, but certainly worth testing; high productivity products might have a real niche on a limited portion of the land-base, preferably on land now in weeds or pasture) Do we hope to develop a new supply of furniture-quality hardwoods? (possible, but not likely to overcome the innate abilities of eastern forests and processors; have we really explored the potentials of native hardwoods in this regard? i've seen some magnificent wood form bigleaf maple... what about bitter cherry?) Sentimental value? If nostalgic about particular species, by all means plant them in yards, bulevards and fence-rows, but not as a substitute to natural forests. vs. the Dangers: Shouldn't we worry about the potential for escapes (e.g., tree of heaven), hybridizations, and unforseen pest-fodder/increasers? That such plantations might replace natural habitat for wildlife, some of which may have species-specific affinities? (Again, my primary concern is with the replacement of natural forests, not the practice of arboriculture on agricultural land) I find it interesting that foresters often advocate religious adherence to tree seed (provenance) transfer quidelines, but repeatedly call for the inter-continental and trans-continental movement of species. Let's suppose that Juglans nigra, Quercus rubra, Acer saccharum, and Fraxinus americana are a raging success on Vancouver Island; do we really want them adopted as preferred forest regeneration species in that biogeographic province? So, Mr. Bennett, i hope you can obtain some seed, and i'll be curious to see the growth results (i've heard warnings, from Dr. John Worall, I believe, that those species will not adequately fill their chilling requirements in coastal B.C.), but i hope your plantings are not too successful! I'd be curious to hear different perspectives about the costs and benefits of exotic introductions: Eucalyptus in southern Africa, Pinus radiata in New Zealand, P. contorta in Sweden, Sitka spruce in Scotland, and Douglas-fir throughout Europe....has it been worthwhile? Regards, Phil Burton ========================================================================= burton@unixg.ubc.ca /* "It's not that I just work here; */ Philip J. Burton, Assistant Professor /* here is just where I work." */ University of British Columbia Department of Forest Sciences tel. 604-822-6020 #270 - 2357 Main Mall fax. 604-822-5744 Vancouver, B.C. Canada V6T 1Z4 =========================================================================
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