college of agricultural

"If it's excessively warm before application -- and water is not limiting -- weed growth speeds up, resulting in larger plants that may have a better chance of surviving the herbicide," said co-author Marty Williams, an ecologist with USDA-ARS and affiliate professor in the Department of Crop Sciences, part of the College of Agricultural, Consumer and Environmental Sciences at Illinois.

"Honey bees pollinate various crops across North America, so it's important to understand how they're influenced by beekeeping strategies and their environment, particularly under increasing weather variability," said Gray, who did her graduate research in the lab of Christina Grozinger, Publius Vergilius Maro Professor of Entomology in the College of Agricultural Sciences.

That no longer appears to be a viable option, said Kelly Wrighton, associate professor in the College of Agricultural Sciences' Department of Soil and Crop Sciences, whose lab led the work.

"Although both sexes showed a positive correlation between heat tolerance and size, male squash bees had a greater change in their critical thermal maximum per unit body mass than females, suggesting that there may be another biological trait influencing the impact of body mass on heat tolerance that differs between the sexes," said study co-author Margarita López-Uribe, associate professor of entomology and Lorenzo L. Langstroth Early Career Professor in Penn State's College of Agricultural Sciences.

"Many bee species can actively control their body temperature independently from ambient temperature conditions and thus potentially mitigate effects of temperature extremes," said co-author Rudolf Schilder, associate professor of entomology and biology in the College of Agricultural Sciences and the Eberly College of Science.