Remove surplus sugar frames
The Nordic brown bee’s winter food consumption is very low. There is, in fact, usually plenty of winter food left in ten-frame Langstroth hives used in Finland, as well as in eight-frame Norwegian hives or eight-frame LågNormal hives as used in Norway in spring after the cleansing flight.
Fall feeding with 12 to 18 kg of dry sugar easily leaves half of the winter feed untouched, depending on the surplus honey left over in the overwintering hive. That said, the queen might have difficulties finding empty cells for laying eggs, which is one of the first factors in increasing swarming behavior. In light of this, some beekeepers systematically remove extra food frames from colonies in spring and replace them with empty built combs.