Research achievements and adoption of no-till, dryland cropping in the semi-arid U.S. Great Plains

The Great Plains region of the United States is an area of widespread dryland crop production, with wheat being the dominant crop. Precipitation in the region ranges from 300 to 500 mm annually, with the majority of precipitation falling during hot summer months. The prevailing cropping system is a two-year rotation of wheat and summer fallow. The adoption of no-till practices has resulted in greater precipitation storage and use efficiency, which has led to greater cropping intensity, higher productivity, more diverse crop rotations, and improvements in soil properties. In Colorado, for example, a no-till rotation of winter wheat–maize–fallow increased total annualized grain yield by 75% compared to winter wheat–summer fallow. Soil erosion was reduced to just 25% of that from a conventional tillage wheat–summer fallow system. The primary challenge with reducing fallow frequency is the increase in yield variability and risk of crop failure. Improved approaches for choosing crop or fallow are being developed based on soil water content and forecasted weather. Development of alternative crops, crop rotations, and integrated livestock systems that are sustainable from both economic and ecological perspectives is an on-going effort. Other research is addressing adaptation of cropping practices to climate change and the potential for dryland biomass crop production for the developing biofuel industry.

► No-till is a key management strategy to deal with the high level of temporal and spatial climate variability in the U.S. Great Plains.
► No-till in the Great Plains is associated with intensified rotations that reduce fallow, improve precipitation use and soil properties.
► Adoption of no-till has altered the pest complex for wheat in the Great Plains, including insects, diseases, and weeds.
► Sustaining crop production in the Great Plains is highly dependent on reducing soil erosion, maintaining soil organic matter, and economic profitability.