Again, studies on land use and bee performance are useful but up to a point, as Johnson et al state clealy:

It is important to note that while model selection identified landscape composition
as the best predictor of colony food and wax accumulation, the amount of unexplained
variation in our models was high, indicating that factors other than the ones we measured
are also at play in the determination of colony success. 

We also suggest caution in generalizing our results beyond our study region. While the
landscape of Ohio is broadly similar to much of the American Midwest, it would be
premature to extend our findings to other ecoregions that may differ strongly both in
natural flora and in agricultural practices.

On the other hand:

[Results] indicate that food accumulation and wax
production increase with surrounding cropland and decrease with forest/grassland. This
finding seems to contradict the conventional wisdom that agricultural land conversion
threatens honey bee nutrition through the depauperation of floral resources relative to
semi-natural environments

Certainly in my area, honey production is relatively low due to the fact that land use is primarily forest, and there is almost no agriculture. Most of the best honey plants are "invasive" species.

PLB

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