Every acre of Iowa soil must be considered strictly within the corn belt.
The extreme northern counties of the state are capable of producing yields of corn which compare very favorably with the yields of the southern counties or of districts in other states with even a longer growing period. It is merely necessary to find and use in northern Iowa varieties of corn which are adapted to a shorter growing season by their ability to produce and mature a good crop quickly.
Hughes, H. D.
"Silver King. A corn for northern Iowa.,"
Bulletin: Vol. 12
, Article 1.
Available at: https://lib.dr.iastate.edu/bulletin/vol12/iss138/1