Utilizing Combine Yield Monitor Data to Verify a Variable Rate Corn Planting Recommendation.

Combines equipped with yield monitors are being used to collect on farm data. The accuracy of this information is in question. The objective of this research was to develop protocols for using yield monitor data to validate a variable rate seeding recommendation. Yield monitor protocols were determined by comparing corn (Zea mays) hand-harvested and yield monitor data collected from 237 areas in an eastern South Dakota field. Analysis of variance (ANOVA) determined the yield monitor and hand-harvested yields were similar when the data was aggregated into plots 70 m long. This protocol was used to validate a variable rate corn seeding recommendation in experiments conducted in Webster, Winner, and Beresford, SD. Five seeding rates were planted in strips. Each population rate was replicated twice. A variable rate seeding recommendation ((Population)=12700+1.5261(Yield)) was tested by using three years of previous corn yield monitor data (kg/ha) to determine yield. Tukey’s test was used to determine statistical similarities between the recommendation and the optimum plant populations developed with 70 m of yield monitor data. Due to abnormal weather conditions at Beresford and Winner in 2012, the recommendation was statistically different from the optimum plant populations. However, at Webster the weather was normal, and there was no statistical difference between the recommended seeding rate and optimum plant populations. Based on information obtained in 2012, this method proves effective when weather patterns and growing conditions are normal. This process can be used for any type of variable-rate agronomy input, and provides a method for researchers, consultants, and producers to check the validity of their variable rate recommendations using combine yield monitor data.