Influence of Crop Rotation and Tillage on Soil Physical Properties in Southwest Oklahoma.

Influence of crop rotation and tillage on soil physical properties in southwest Oklahoma Silvano L. Abreu1, Chad Godsey1, Jeff Edwards1, Gary Stricland2 1Department of Plant and Soil Sciences, Oklahoma State Univesity. Stillwater, OK;2Southwest Research and Extension Center. Altus, OK. abreu@okstate.edu No-till adoption in Oklahoma has been slow due to low biomass production, climatic conditions, and cultural barriers. The objective was to evaluate the effect of crop rotations and tillage practices on soil strength, bulk density, total porosity, root biomass and soil organic carbon (SOC) in a Fine, mixed, superactive, thermic Vertic Paleustolls, southwest Oklahoma. In 2002, a crop rotation and tillage study was started to evaluate crop rotation and tillage influence on soil fertility and crop yield, crop rotations consisted of continuous grain sorghum, continuous wheat, continuous cotton, wheat-double crop grain sorghum-cotton, cotton-wheat-grain sorghum, cotton-wheat, and cotton-grain sorghum and two tillage practices (1-conventional till and 2- no-till). Soil physical parameters measured included soil strength, bulk density, root biomass and organic carbon. Soil strength decreased as tillage decreased. Decreasing tillage and increasing crop diversity has positively influenced soil physical properties.