EMMETSBURG – Speaking to a full audience at the Iowa Lakes Community College, Dean Gronemeyer, District Conservationist laid out the benefits of reduced tillage farming.

“There are some pretty powerful reasons for converting to less tillage,” said Gronemeyer. These include;

• Reduce sheet and rill erosion by up to 90 percent.

• Reduce wind erosion.

• Improve soil organic matter.

• Reduce CO2 losses from the soil.

• Reduce soil particulate emissions.

• Increase plant-available moisture.

• Provide food and escape cover for wildlife.

While the best solution to prevent erosion is to plant grass, there are ways to minimize soil loss when growing crops. Using residue management systems, erosion doesn’t have to occur.

“With a no-till system, the soil and residue is undisturbed from harvest to planting except for nutrient injection,” said Gronemeyer. “Planting or drilling is done in a narrow seed bed, or slot.”

In a strip till operation the soil and residue is undisturbed from harvest to planting except for strips up to a third of the row width. The soil tillage intensity rate, or STIR, shall not exceed15, he stressed.

STIR, which ranges from zero to 200, takes into account speed, depth, surface disturbance percent and tillage-type parameters to calculate a tillage intensity rating for the system used in growing a crop or a rotation.

Besides halting soil erosion, soil benefits from less tillage with more organic matter. Organic matter is heavily dependent on residue and crop management. Cover crops can be another part of the equation.

Keeping soil in place is only the beginning of soil conservation, said Gronemeyer. Soil has to function well. It must hold nitrogen, phosphorus, and pesticides in place, while being kept out of surface water.

Soil must deliver nutrients and water to plants as they need them. Organic matter helps soil perform all these functions.

Energy savings that are realized from using less tillage are advantageous to producers, said Gronemeyer, even more so after we saw where fuel prices can go last summer. “In a minimum tillage situation, less machinery is needed and fewer trips across the field are required. That saves both time and energy.” He encouraged farmers to estimate their energy savings by going to the NRCS Web site and by visiting ecat.sc.egov.usda.gov.

Comparing systems

Criteria for no-till

• No burning of crop residue.

• Residue uniformly distributed over entire field.

• No full-width tillage regardless of tillage depth.

• Plant or drill directly into untilled residue slots.

• Row cleaning devices shall not exceed 30 percent of row width.

• STIR shall not exceed 10.

Criteria for strip-till

• No burning of crop residue

• Plant or drill directly into tilled seedbed prepared in narrow strips that was tilled prior to planting.

• Fertilizer placement, rotary tiller, sweeps, coulters or row cleaning devices shall not exceed 30 percent of row width

• STIR shall not exceed 15.

Contact Renae Vander Schaaf by e-mail at renaefarmnews@gmail.com.