On Monoculture and the Structure of Crop Rotations
2006
Hennessy, David A.
An issue when seeking to identify rotation choice is persistence in yield‐enhancement and input‐saving carry‐over effects. Focusing on carry‐over length and the monoculture decision, we use quasi‐convexity of choice functions to develop price‐independent and price‐dependent principles concerning rotation structure. Iowa corn‐soybean rotation data suggest corn has one‐year memory. For corn, soybeans in the prior year is yield increasing (16.5 bu./ac.) and nitrogen saving (51 lb./ac.). The hypothesis that soybean has two‐year memory cannot be rejected. Corn in the prior year (two years) increases yield by 7 bu./ac. (11.6 bu./ac.). We simulate to find price and practice subsidy levels that support different rotations.
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