>In answer to the recent inquiry about the European hornet - Vespa crabro
>- there is information about it in "The Yellowjackets of America North of
>Mexico", USDA Handbook 552.
 
Unfortunately, this publication is no longer available from the Gov't
Printing Office.   Its author, sadly, recently passed away.  If anyone can
get hold of a copy it would be worth keeping.  I believe the author was Dr.
Akre, but am not sure what lab or univ. he was associated with.  The book
has some photos of some extraordinary nests, many of Vespula germanica.  I
would be interested to know if anyone else in the US currently is
considered to be an authority on wasps, or if there have been any more
recent publications along these lines.