Weather, and especially rainfall, is the most important factor affecting crop yields in Iowa. The moisture used by crops comes from two sources- crop-season rainfall and soil reserves. How do we stand for 1959?
Duncan, E. R. and Shaw, R. H.
"Crop Yield Outlook for 1959,"
Iowa Farm Science: Vol. 13
, Article 7.
Available at: https://lib.dr.iastate.edu/farmscience/vol13/iss7/7