Influence of Precipitation, Temperature, and 55 Years On Winter Wheat Yields In Western Kansas.

Historical winter wheat yield trends and yield response to environmental and climatic conditions may help estimate future yields and evaluate past yield improvement. Data was compiled across the four western Kansas experiment station locations (Colby, Garden City, Hays, and Garden City) from variety trials from 1955 and 2010. Across this time period, irrigation increased yields 1200 kg ha^-1, and reported freeze damage reduced yields 540 kg ha^-1. Warm fall (Oct-Nov), early spring (Apr), and Jun temperatures tended to reduce yield, while late spring (May) temperatures tended to increase yield. In dryland, precipitation in months prior to May (Oct-Apr) increased yield. Across all of western Kansas, yields increased about 34 kg ha^-1 per year. At Colby and Hays dryland yields increased 54 kg ha^-1 per year, and at Garden City and Tribune dryland yields increased 20 kg ha^-1 per year. October precipitation and Apr temperature affected yields more at Garden City and Tribune than year. Future wheat breeding and cropping systems research should work to improve stand establishment and minimize freeze injury.