Crop Diversity in Winter Wheat Cropping Systems.

The production capacity and sustainability of existing dryland winter wheat cropping systems have been limited due to lack of proper resource use management strategies and diversity. Managing limited precipitation water and other important soil nutrient resources are the key elements of success of dryland farming in the Western US. Efforts in introducing diverse rotation crops in winter wheat cropping systems have been challenging due to limited water. Therefore, a fallow rotation of 11 to 16 months has been practiced with an objective of saving some moisture to fulfil the water requirements of following cash crop and to avoid crop failures. Although this practice is widely accepted and practiced in many dryland wheat systems, evaporation during peak precipitation months and water use of volunteer weeds during fallow can present new challenges for improving water use efficiency. In addition, the cultivation of fallow during summer causes significant wind and water erosion that may result in loss of nutrients from top soil. Keeping the concerns of resource use efficiency and long-term sustainability of current dryland winter wheat cropping systems in view, an innovative plan of considering 16 crops as fallow replacement rotation crops will be evaluated for water dynamics and nutrient recycling, production capability, and sustainability in this project. Diversity in the dryland cropping systems will not only reduce the risk of long-term sustainability but also increase the resource use efficiency and farm-level income security through diverse crop commodities and robust marketing options.