Predicting Winter Wheat Yield Loss from Soil Compaction in the Central Great Plains of the United States

Adoption of methods to minimize the effects of soil compaction on crop production by farmers has been slow. Often farmers do not equate degradation of soil physical properties with reduction in crop yield. The objective of this study was to determine the potential yield loss caused by degradation of soil physical quality due to compaction. Soil conditions and winter wheat (Triticum aestivum L.) yields were observed on the Alternative Crops Rotation study at Akron, Colorado in 1996 and 1997. Changes in soil physical properties were determined by observing changes in the soil Least Limiting Water Range (LLWR), which includes limitations of water holding capacity, soil strength and soil aeration, on crop production. Grain yield decreased approximately 1,000 kg ha(-1) per 0.1 unit decrease in LLWR, showing that soil compaction can cause serious yield reductions if not managed properly. Soil compression curves were developed to help predict the amount of soil compaction, and subsequent yield loss, to be expected with wheel traffic at various tire pressures and soil moisture conditions. Methods such as controlled wheel traffic or the use of low-pressure tires should be used to reduce soil compaction and maintain soil productivity.