RUNOFF, EROSION, AND SOIL QUALITY CHARACTERISTICS OF A FORMER CONSERVATION RESERVE PROGRAM SITE

No-till and moldboard plow tillage systems were established on a forme r Conservation Reserve Program (CRP) site in southwest Iowa. Runoff ra tes from simulated rainfall events were significantly greater on sites returned to crop production than from adjoining undisturbed CRP areas . Substantial soil loss was measured from the moldboard plow treatment s, hut no significant differences in erosion rates were found between the undisturbed CRP and no-till management systems. No-till management maintained levels of soil quality similar to those of CRP by preservi ng soil structural integrity and reducing losses of soil organic matte r (SOM) associated with tillage. Conservation tillage systems which ma intain residue materials on the soil surface may be well suited for fo rmer CRP areas which are used as cropland.