On May 12, 2009, at 12:00 AM, BEE-L automatic digest system wrote:

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The american elm

    Having done my graduate work on Dutch Elm Disease I've spent about  
8 years in elm tree canopies around the NE.  The monumental Mall in  
the capital was/is surrounded by American Elms.  I have not been there  
for 20 years.

    Elms flower early in the year, I have a siberian in my back yard  
that is raising seed now.  The Elms tend to seed prior to leaving so  
it is an early (upstate NY) source for pollen--I believe it to be low  
quality.  It is not a nectar source as the Ulmaceae does not have  
floral nectaries. The tree is normally a wind pollinated species and  
may be an emergency alternate source of pollen in the spring.

   CAUTION:   The Dutch Elm Disease has evolved a more virulent form  
that is capable of taking down some of the "resistant" cultivars.  The  
other major disease that assisted the depletion of the American Elm  
was a (introduced) pathogen that is vectored by a flugorid (flying  
leaf sucking insect) called Elm Yellows--a Phytoplasm!

   I love American Elm but not sure they will ever recover the majesty  
they once held in American cities!

Mike
Dutch Elm Disease was very very good to me--paid my graduate education!

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