Residues of the Insecticides Carbaryl and Monocrotophos in Honeybee Colonies

SummaryThree honeybee colonies were placed in each of 3 fields of alfalfa. One field was sprayed with carbaryl and one with monocrotophos; one was untreated. Both insecticide treatments killed bees; carbaryl residues were found in trapped and stored pollen and in honey, but monocrotophos only in trapped pollen. The foraging ability and size of the colonies were apparently not affected.