Even in Oklahoma, Robinia pseudo-acacia is a hit and miss operation for 
the following reasons:

1) They take a breather at some years; they do not bloom every year 
(Flowering is costly investment for the trees, obviously).
2) When they do bloom, the weather is too cold for the bees to forage 
around here.
3) Typically they bloom around April 19th around Shawnee, OK, which often 
signals the start of nectar flow; however, they started to flower about a 
week earlier this year, possibly due to wet early-spring we had. 
4) Again, around here it is difficult to find large patches of them, 
making it cost-ineffective to relocate bees for a few stands, here and 
there.  
5) As a result, it is difficult to isolate pure black locust honey, as 
such, by the time I pull mine around mid-July.  My bees may have consumed 
all of it for early brood-building.

Nevertheless, when the above factors work favorably for the bees, I have 
no doubt, the honey should command a high price; even the aroma of its 
bloom is intoxicating.  Frankly I have been so far unable to gather black 
locust honey, singularly.

Yoon

******************************************************
* Full guidelines for BEE-L posting are at:          *
* http://www.honeybeeworld.com/bee-l/guidelines.htm  *
******************************************************