Steve,
 
You probably are referring to Common Purple Vetch.  It's used in forage
blends for hay and silage.  In my area (San Joaquin Valley CA) it is mostly
an "escaped" plant not cultivated much anymore.  Good news though, it
produces well here.
 
I just got back from a vacation in your area and with the temps the way they
are I wouldn't be surprised if it produced for you.  Here the flow doesn't
really get going until the plants blooming cycle in on the downward side
(begins to dry up if non-irrigated) and it lasts about 3 weeks.  I don't have
any experience with vetch in an irrigated setting.
 
How about the wild alfalfa that dots the roadways and range areas where you
live, does it produce?  I couldn't really smell the nectar so I figured it
didn't.  Here's another question for you and the others out there: Why is it
that the Alfalfa seed fields seemed to be only pollinated by Leaf Cutters and
very few Honey Bees.  In my area pollination of seed fields is mostly by
Honey Bees.  Hope this helps.
 
Brian Tassey
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