ABSTRACT
The soil type at the native sod site is a Duroc loam, a fine silty, mixed, mesic Pachic Haplustoll. Soil texture within the native sod treatment is about 40% sand, 35% silt, and 25% clay at the 0- to 15-cm depth. Soil samples have been collected and numerous soil measurements made at irregular intervals and various incremental depths. Decreased soil stability with cultivation was found to be paralleled by a reduction of organic matter concentrations and an increase in microaggregate formation. The stratification of crop residues, organic matter, and soil organisms within the profile of no-till is suggested as a major mechanism for immobilization of N near the soil surface as compared to conventional tillage. J. W. Doran’s findings were reiterated by R. F. Follett and G. A. Peterson, who found no-till resulted in the maintenance of higher soil organic matter compared to plow tillage, especially in the surface 5 cm.
