A study of the relative crop production costs for different machinery and land combinations illustrates the kinds of pressuures that are at work in the area as farm operators attempt to acheive the cost economies possible.
Mayer, Leo V.; Heady, Earl O.; and Ihnen, Loren
"Why the Rapid Farm Adjustments in Southern Iowa?,"
Iowa Farm Science: Vol. 18
, Article 8.
Available at: https://lib.dr.iastate.edu/farmscience/vol18/iss5/8