2009-09-072009-09-071984https://hdl.handle.net/10365/5932The impact of technology on grain yield can be shown by plotting yield versus time. Regression models can be used to obtain equations that show how much yield has changed with time. Equations obtained in this manner may not properly account for variations in climate. This article attempts to avoid this problem in their analysis by evaluating spring wheat yield in terms of available water or evapotranspiration using historic and current information.North Dakota State UniversityCrop productionWheatArticle