University extension service hybrid maize yield trials, 1934 - 2014

Data from hybrid maize yeild trails conducted by the University of Illinois at Urbana-Champaign, Iowa State University, Kansas State University, and the University of Nebraska-Lincoln between 1934 and 2014. This digitized data was orginally published in Agricultural Experiment Station and Cooperative Extension Service reports and bulletins distributed in paper and, in later years, as Excel files. The data set includes brand and hybrid names, trial location, and yield (bushels per acre) for all trials and years. Additional data on agronomic phenotypes, soil type, and average weather is included when reported in the orginal publications. Details about the orginal publications, data processing, etc. can be found in the included readme file. A GitHub repositiry containing the R code used to munge the data is also publically available and linked as a reference.