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Quoting Dusan Soudek <soudekd@ns.sympatico.ca>:
> During a recent canoe trip down the West River St. Mary's (in
> Guysborough Co.) I noted only a single mature live elm tree, and
> three or four standing dead ones, along maybe 80 km of the river.
> (Elm trees, dead or alive, stand out from their neighbours due to
> their unmistakeable shape of their crowns.)
* the Elms died in eastern Ontario around 1970, so we've had 40 years
of selection for resistance, and we've got plenty of Elms, though not
many big ones yet, and each summer some die. We're having a discussion
of this on our NatureList, and there's been disagreement on how much
progress selection for resistance has gone (partway down this thread -
http://groups.google.com/group/naturelist/browse_thread/thread/0b711a1567cc434a/451d287668f93cdb?hl=en%C7%83d287668f93cdb ). I've gone out on a limb to suggest that the first generation including fully resistant trees has already germinated, though, of course, they're still a small fraction of the whole
population.
I guess Nova Scotia was hit a bit later than eastern Ontario, so the
selection for resistance wouldn't be expected to be as advanced as it
is here. The critical thing is the presence of young trees that
reproduce by seed before they're taken out by DED.
fred.
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Frederick W. Schueler & Aleta Karstad
Bishops Mills Natural History Centre - http://pinicola.ca/bmnhc.htm
Mudpuppy Night in Oxford Mills - http://pinicola.ca/mudpup1.htm
Daily Paintings - http://karstaddailypaintings.blogspot.com/
South Nation Basin Art & Science Book
http://pinicola.ca/books/SNR_book.htm
RR#2 Bishops Mills, Ontario, Canada K0G 1T0
on the Smiths Falls Limestone Plain 44* 52'N 75* 42'W
(613)258-3107 <bckcdb at istar.ca> http://pinicola.ca/
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