Iowa: ICM Practices Adopted by Iowa Farmers

For years extension educators have promoted various Integrated Crop Management (ICM) techniques. Integrated Crop Management is a sustainable approach to managing crop production, using a combination of biological, cultural, and chemical tactics that reduces pests to tolerable levels that minimize economic, health, and environmental risks. Many producers selectively use ICM practices, but few implement the total package.

In the fall of 1993, ISU Extension's IPM program initiated a two-year statewide ICM training program demonstrating that a complete ICM package is profitable and environmentally responsible.

For the program, ISU Extension provided digitized soil maps, soil sampling from a major soil mapping unit, scouting services, and appropriate crop management recommendations. Crop enterprise records were kept and summarized to provide accurate economic analysis.

IMPACT

• Heavier planting rates increased corn yields from 10 to 15 bushels per acre. Soybean yields were maintained while planting rates were reduced by 40,000 seeds per acre.
• Planting a recommended variety resulted in a 10-bushel advantage over the traditional variety.
• A $20 per acre reduction in potassium and phosphorus fertilizer costs resulted in fields with previous manure applications.
• Digitized soil maps determined productivity and established a successful cash rent bid f or 660 additional crop acres.
• Alternative herbicide programs were designed for atrazine management areas.
• One cooperator used banding, reduced herbicide rates, spot spraying, and mechanical control (rotary hoeing and cultivating) to reduce herbicide costs to $8.92 per acre for corn and $26 per acre for solid-seeded soybeans.
• With no yield reductions, one cooperator reduced his nitrogen fertilizer rate from 60 to 90 pounds per acre following alfalfa or manure applications.