Effects of direct application of selected pesticides upon honey bee colonies

The purpose of this investigation was to determine the effects of seven selected pesticides upon colonies of honey bees. Tests were conducted in a specially constructed building on The University of Tennessee Agriculture Campus. Healthy frames from strong hives were placed in glass observation hives. These frames were then treated by direct application with one of the seven pesticides to be tested: carbaryl, malathion, diazinon, carbofuran, Kelthane, alkanolamine salts of 2,4-D, and low-volatile ester formulation of 2,4-D. The results indicated that carbofuran, diazinon, and malathion are highly toxic to bees when the hive is contaminated by direct application. Carbaryl caused only light mortality. Kelthane is nontoxic, as were both formulations of the herbicide 2,4-D. An attempt was made to construct a "dead bee trap" which would be functional on an observation hive of the type used in this experiment. All attempts were unsuccessful. A laboratory experiments, with the greater wax moth Galleria mellonella (L.), was conducted during the winter months. Different media were tested and the number of larval instars studied.