Agricultural Engineering/Agronomy, Central Iowa, and BioCentury Research Farms

Examining the Impact of Corn Rootworm on Silage Corn

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Abstract

Western corn rootworm (Diabrotica virgifera virgifera; WCR) and northern corn rootworm (Diabrotica barberi; NCR) larvae are the most significant insect pests of corn across the Midwest region. In areas that must feed livestock, especially dairy cattle, continuous corn production is common and the incidence of corn rootworm larvae affecting yield is high. Additionally, corn severely impacted by weather events (hail, drought, etc.) is commonly harvested for silage as a rescue practice. The economic injury level and yield losses associated with root injury are well understood for grain corn. However, these relationships have not been investigated for silage corn production since the early 1990s. Since then, the evaluation criteria for corn rootworm larval injury have changed, corn hybrids with Bt proteins for corn rootworm management have become available, and corn rootworm populations have become resistant to these hybrids. Plus, market conditions and production costs have changed significantly. This research aims to understand the impact of corn rootworm on silage quality and quantity metrics and determine the economic injury level for silage corn.

How to Cite:

Hodgson, E. W. & Dean, A., (2025) “Examining the Impact of Corn Rootworm on Silage Corn”, Iowa State University Research and Demonstration Farms Progress Reports 2024(1), 14-16.