The successfully mated queens fly to the ground and hibernate 2 to 5 inches deep in the soil. The production of reproductives signals the end of the colony's life. The overwintering queens emerge the next spring to complete their life cycle. They contribute immeasurably as pollinators of wild flowers and crops. Much of the pleasure and profit from natural bumble bee activities are difficult to measure in economic terms.
Bumble bees pollinate many wild flower species that birds and small mammals rely on for food.
Although bumble bees are normally harmless when foraging, a disturbed colony can be nasty. Guard bees stand ready to protect the nest against predators, including skunks and man. The worker bumble bee can sting repeatedly without sacrificing her life. Precautions should be taken when working or playing in areas that are likely to be inhabited by bumble bees. This is especially true when mowing fields or trimming weeds around trash or wood piles.