I put 3 hives on 25 hectar canola field. I hope that they get something. It is windy place. Too big field mere canola.
A friend had scales on a few hives that are in and amongst the canola field where the canola plants shelter the hives from the winds, he also had hives at the edge of the fields were they where not sheltered from the harsh winds that can blow in the open terrain.
The hives that were sheltered by the plants brought .5kg more necktar each day back to the hive.
When the bees have to work less at keeping a constant temperature in the hive the harvest increases