The frigid temperatures that gripped Iowa dur­ing the past winter knocked out some yield-robbing insects but had little impact on others, university experts said as they look ahead to the 2014 growing season.

Predicted mortality rates of bean leaf beetle in Iowa are the highest in 25 years, ranging from 89 to 99 percent, said Iowa State University (ISU) entomologist Erin Hodgson. The bitter cold also likely contributed to an increase in mortality of corn...