Shelterbelts (field windbreaks) are an important tool for farming in semi-arid areas but are not commonly used. An obstacle to the adoption of shelterbelts is the lack of site-specific information about the benefits and costs associated with establishing and maintaining them. A group of researchers has been developing a modeling system that will estimate site-specific effects, benefits, and costs for sheltered fields that produce maize or corn (Zea maize) and soybean (Glycine max) in the US Corn Belt region. A key component of the modeling system is the use of the CROPGRO-Soybean and CERES-Maize models to simulate yield response to microclimatic changes across a sheltered field. In this work, we tested the ability of both models to simulate yield in a sheltered field, evaluated the potential yield increase of shelterbelts based on long-term simulations, and compared the influence of shelter induced changes in temperature and wind-run on yield. Both models simulated yield increases due to shelter. The soybean model was more responsive to microclimatic differences than the maize model. Long-term simulations generally showed a field level increase in yield due to shelter for maize and soybeans with an average increase of 4.1 and 3.3, respectively. Change in wind-run due to shelter is more important in increasing yield than changes in temperature. The CERES-Maize model seems to be more sensitive to changes in wind-run than the CROPGRO-Soybean model.
