Researchers have found that urban and suburban bees have a greater variety of diet than Farmland bees.
Hives from Kensington Palace showed evidence of eucalyptus and elderberry, while suburban sites (e.g. around the University of Worcester) showed a rich mix including lily, blackberry, rowan trees, and oilseed rape.
At more rural National Trust sites near farmland in Yorkshire and Somerset the hives were overwhelmingly dominated by oilseed rape pollen.
According to Matthew Oates adviser on nature conservation to the National Trust
What is clear is that there is a far greater range of plants in urban and particularly suburban settings than in many of our contemporary agricultural landscapes.
The difficult area for bees is modern mainstream farmland: intensive arable land for wheat, barley, oilseed rape, and also dairy beef and sheep grasslands.
There really is so little forage for bees in those modern internsive farming systems.