Tuesday, November 14, 2006

Impact of Stubble Height on Soil Moisture Dynamics.

Scott Staggenborg and Lucas Haag. Kansas State Univ., 3709 Throckmorton Hall, 3709 Throckmorton Hall, Manhattan, KS 66506, United States of America

Previous work has shown the impact of surface residue on soil moisture content.  The impacts of residue are most important in the High Plains where evaporative demand is high and fallow periods are used to replenish soil water supplies.  Recent advances in harvesting of small grains utilizing a stripper header have created new residue properties following harvest.  A field in Decatur County, Kansas was selected to host three replicated winter wheat stubble height treatments.  The treatments consisted of near bare soil, conventional harvest, and stripper header harvest.  An automated soil moisture monitoring system was installed to obtain volumetric readings every minute and record an hourly average.  Sensors were placed at a depth of 2.5 cm and 20 cm below the soil surface.  Soil temperature was also obtained using thermocouples.  Analysis of data will aid in determining the impact of stubble height on soil moisture retention, evaporation, and grain yields of the following crop.  Improvements in soil water storage will enhance overall system productivity and improves opportunities for intensifying High Plains crop rotations.