Greenpeace Germany made claims in a report that it believes that the western bean cutworm is a “new plant pest” that was “caused by genetically engineered corn.” Refuting the claim is an article from the Journal of Integrated Pest Management. Authors of the JIPM article say Greenpeace Germany’s results showed a “surprisingly simplistic conclusion” about the spread of the WBC over the past decade.

In "Genetically Engineered Bt Corn and Range Expansion of the Western Bean Cutworm (Lepidoptera: Noctuidae) in the United States: A Response to Greenpeace Germany," corresponding author William Hutchison, professor and chair of the University of Minnesota Department of Entomology, and his co-authors maintain that the Greenpeace report fails to consider broader ecological and agronomic factors which explain why the WBC's range has expanded. These additional factors include insect biology, synchrony of insect and corn phenology, reduced insecticide use, increases in conservation tillage, soil type, glyphosate-resistant crops, insect genetics, insect pathogens, pre-existing insect population densities, and climate change.

In addition, Greenpeace’s claim that WBC is a new pest is just wrong. According to the authors, “the WBC was documented throughout the western Great Plains from Mexico to Alberta where it was found in the mid 1950s.”

The WBC was originally collected in Arizona in the 1880s.

The authors explain some of the reasons for the spread of WBC include:

  • Increasing use of conservation tillage favors larvae survival in the soil
  • Reduced or eliminated use of insecticide applications as a result of increased use of Bt hybrids.
  • Climate change.