Iowa farmers adopt ICM practices

Extension educators have been promoting various Integrated Crop Management (ICM) techniques for years. Many producers, farm managers, professional agronomists, and crop consultants have used ICM practices selectively, but few are implementing the total ICM package.

In the fall of 1993, a two-year statewide ICM training program was initiated by ISU extension's program for Integrated Pesticide Management (IPM). One of the sites was located in north central Iowa where three growers who farmed a total of 1,947 acres participated in an ICM demonstration. The goal was to show that a complete ICM program could be profitable and environmentally responsible.

The three cooperators received digitized soil maps of the land in the demonstration program. Soils were sampled by major soil mapping unit and appropriate fertilizer recommendations were developed. Cooperators also received recommendations on variety selection, seeding rates, tillage and machinery selection, and timing of field operations. Scouting services were provided throughout both growing seasons in the project.

All three cooperators maintained enterprise records, which were summarized to provide an accurate economic analysis. In addition, extension staff conducted on-farm demonstrations related to manure application rates, use of nitrogen testing, date-of-planting, and special weed control techniques. These on-farm demonstration sites were used as teaching stops during county crop tours.

Results of the two-year ICM project included:

  1. Potassium and phosphorus costs were reduced $20 per acre in fields with previous manure applications. One cooperator purchased a new manure spreader with fertilizer dollar savings.
  2. One cooperator used the digitized soil maps to determine productivity and establish a successful cash rent bid for 660 additional crop acres.
  3. Planting a recommended variety resulted in a 10-bushel per acre per year yield increase over a traditional variety.
  4. One cooperator reduced his nitrogen fertilizer rate 60 to 90 pounds per acre following alfalfa or manure applications with no reduction in yield.
  5. Atrazine management areas were identified and alternative herbicide programs were designed for these areas.
  6. One cooperator used banding, reduced herbicide rates, spot spraying, and mechanical control (rotary hoeing and cultivating) to reduce chemical costs to $8.92 per acre for corn and $26 per acre for solid-seeded soybeans.
  7. Corn yields were increased 10 to 15 bushels per acre with heavier planting rates. Soybean yields were maintained when soybean planting rates were reduced by 40,000 seeds per acre.
  8. One cooperator replaced his 36-inch planter with a 30-inch planter based on ISU Extension's recommendation.
  9. Cooperators indicated that they were pleased with the services provided by ISU Extension, and that they became aware of and used extension services that they had not used before.
  10. One cooperator successfully used Poast-tolerant corn varieties to control a severe wirestem muhly problem in continuous corn plantings.

As a result of their participation, cooperators were more confident in making their own decisions and more selective in accepting the advice given by agricultural professionals with a product or service to sell. Cooperators said the planning segment of the ICM program required that they formally identify short- and long-term goals and that this offered an "excuse" to raise and discuss these issues with other family members. The participants indicated they enjoyed the recognition they had received as being an ISU Extension cooperator, and that they wished to continue the relationship even if they had to pay for the service.

This article originally appeared on pages 184-185 of the IC-476(25) -- November 11, 1996 issue.

Updated 05/23/2005 - 5:24am