Reduced input, diversified systems were more profitable than the high input
monocrop continuous corn system in a Wisconsin study. The WI Integrated
Cropping Systems Trial (WICST) study involved a four-year economics
analysis of three cash grain cropping systems: continuous corn,
corn-soybeans, and corn-soybeans-wheat/red clover.
Gross margins per acre from 1991-1995 were $151 for continuous corn, $204
for corn-soybeans, and $195 for corn-soybeans-wheat/red clover. Gross
margins are gross returns (market value of the crops) minus variable or
direct costs (seed, fertilizer, pesticides, custom operations, leased
equipment, fuel, repairs, interest , and grain drying).
During the four-year study, the corn-soybean system had the greatest
average profitability of the three systems. It usually had the highest
corn yields and was always more profitable that continuous corn. The
soybeans were conventionally drilled in 1992 and 1993, and no-till drilled
in 1994 and 1995. Corn was no-till planted every year with a starter
fertilizer and a 40 # nitrogen credit from the soybeans. Pests were
controlled with standard agricultural chemicals.
Continuous corn was the least profitable option and had lower yields than
corn following soybeans. Direct costs per acre with this system were
always the highest of the three systems. The corn was planted in 30-inch
rows in chisel-plowed soil, fertilized with starter and anhydrous ammonia
(based on soil nutrient tests) and cultivated once. Pests were controlled
with standard agricultural chemicals.
The corn-soybean-wheat/red clover system used no commercial fertilizer, no
insecticides, and only spot spraying of Canada thistle and one emergency
rescue treatment of herbicides in the soybeans in 1992. Corn and soybeans
were rotary hoed and cultivated. Wheat was fall-seeded into the soybean
residue following a light tillage. Red clover was frost seeded into wheat
in early spring to spring to serve as the nitrogen source for the
subsequent corn crop.
For more information contact Kat Griffith, WICST communications coordinator
at 6008/265-8527 or Lee Cunningham, Walworth Co. Extension agent at
1575 Linden Drive
Home Office 608/255-1503
Home Fax 608/255-5885