>It still seems strange that for many years we got tulip
>poplar honey and now the bees don't touch it.

I think the best answer to your questions is simply that bees (and even 
moreso the matrices of their interactions with plants, weather, land use, 
etc.) are so complicated that a lot of what they do can only appear strange 
to us.

There is a lot that blooms at the same time as tulip-poplars, though.  I'm 
amazed, especially at that time of year (I'm in the t-p region, too, 
western NC piedmont), how inconsistent (in terms of type) my crop is from 
year to year.  There are black locusts, blackberries, white Dutch clover, 
blackgums, hollies, wild cherries, privett, persimmons, and more... all 
claimed as possible major honey sources by beekeepers I would generally 
trust.  I would say my spring crops over the last four (not all 
consecutive) years in my most recent location and the last seven years 
altogether in NC t-p territory have all been dramatically different in 
character.

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