It wasn't quite like a pioneer turning sod, but close.

When University of Nebraska researchers began turning under a quarter-section of earth protected by a thick mat of smooth brome grass roots and residue in 1995, they knew they had a big job ahead.

Farmers needed an efficient way to kill the Conservation Reserve Program grass and handle the residue that accumulated for a decade. They also needed recommendations for the best crop choice and to know if they'd encounter unusual production problems converting CRP land back to crops.

The assumption was that since crops grew on most of Nebraska's 1.4 million CRP acres before they were enrolled in the federal program, most would revert to cropland when contracts expired. The question was: how to do it?

"The big problem was getting the grass killed so you could plant in a seedbed in good shape," said NU Soil Scientist Charles Shapiro, a team leader for a five-year Institute of Agriculture and Natural Resources CRP to Crops study in northeast Nebraska.

CRP, begun in 1985, allowed owners of highly erodible cropland to remove their land from production for 10 years. Participants received annual payments in exchange for planting this land to grasses and trees. Most Nebraska CRP contracts ended between 1996 and 1998. CRP sign up now is available for only the most environmentally sensitive land.

When CRP contracts were expiring, producers urgently needed information on how best to recrop the idle acres. Program restrictions banned disturbing CRP land until the winter before it was to revert to crops. For the IANR team, that meant a quick turn-around to get research findings to producers as they became available.

"Everything was needed at once," Shapiro said. "It wasn't anything (producers) could postpone for very long" when contracts expired.

Researchers studied different residue management, weed control, fertilizer and tillage strategies for corn, soybeans and grain sorghum. Producers could see first-hand what worked and what didn't during tours highlighting research on different management options.

Viewing field experiments gave producers "a good sense of the reality that was going on and not just the numbers," Shapiro said. Those numbers helped landlords and tenants renegotiating CRP leases.

To maintain residue on the soil surface, control weeds and reduce the need for additional fertilizer, the CRP to Crops team recommended mowing grass; allowing grass regrowth and then killing with a nonselective herbicide; and planting a rotation of no-till soybeans-corn-soybeans. That first year, remaining residue still protected the soil but kept it cooler and wetter in spring. Soybeans are planted late enough so those conditions weren't a problem, Shapiro noted. Corn was tougher to no-till plant properly into the CRP stubble.

Corn is planted in late April and early May, when grass residue is cold and wet. Plowing under residue helped warm and dry the soil, but left the land more erosion susceptible.

Scientists found grass residue contained up to 120 pounds of nitrogen per acre. However, it apparently wasn't released the first year following CRP, so corn planted the first year needed at least 50 pounds more nitrogen than corn grown in continuously cropped ground.

The project also helped develop a team with expertise to help transition CRP acres back to crops, Shapiro said. More than two dozen individuals representing a dozen entities provided expertise.

Landowner Charles Paulsen offered his quarter section adjacent to NU's Haskell Agricultural Laboratory near Concord for the project, in essence the largest outdoor CRP laboratory in the nation. Funding and in-kind donations came from diverse sources, including private companies, the Crop Production Trust Fund, Layman Foundation, Lower Elkhorn Natural Resources District and the Natural Resources Conservation Service.

– Cheryl Alberts

Agronomist Charles Shapiro was team leader for the CRP to Crops study that involved a dozen entities and more than two dozen people.

Giving producers a chance to see first-hand what worked and what didn't work when converting CRP land back to grain crops was an important part of IANR's CRP to Crops project, a five-year study that wrapped up in 1999. Above: A tour group views various cropping, fertilizer, tillage and weed management options on test plots that cover a hillside near NU's Haskell Agricultural Lab at Concord.

A plow turns under grass residue at one of the IANR team's test plots. Researchers also examined different tactics for managing grass residue in preparation for returning fields to grain crop production.

Farmers take a close look at weed control and other management practices in a soybean test plot during a tour of the CRP to Crops project. Weed control was part of the multi-faceted study.