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Colonies need a huge store pollen in the fall.
First, pollen shortage in nature tells that bees summer is over.
Still bees rear winterbees, and they use existing pollen stores to do that.
When new bees emerbge, they need pollen to end the growing process. Druring first 3-4 days they eate much pollen.
Wintering bees must have a good pollen stode to be good winterers. They accumulate proteinto their fat bodies.
Main reason to nosema is poor pollen storages before winter.
In spring bees cannot start brooding if they have lack of pollen. They must wait first flowers.
If you put one frame of pollen after cleansing flight, the colony gets a good kick up for brood rearing.
Best way to give pollen is to let them store pollen into frames and then take for spring some pollen frames.
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