Water Availability and Other Challenges Facing Cover Cropping in Irrigated Areas of the Southwest.

Regular availability of irrigation water is becoming increasingly challenging in the southwestern part of the United States, and this is affecting the acreage farmed in the region. Due to limited water, cultural practices like cover cropping capable of imparting significant benefits to the farming systems are becoming difficult to practice in the region. Southwest is considered the driest region in the United States with a population growth rate above the United States average, leading to intense competition for water resources. The projected increase in warming is expected to lead to more severe droughts, putting further pressure on water availability in the Southwest. Despite the setback of water availability in the irrigated systems of the southwest, cover crops can improve the soil quality through organic matter additions; increased nitrogen availability by nitrogen fixation of legumes; provide soil cover for erosion protection; suppress weed and diseases; and provide habitats for beneficial insects. Improving soil quality in the southwestern region will make the soil more resilient to drought and other extremes of weather. However, farmers are facing challenges on how to adapt cover crops into their cropping systems in the irrigated Southwest, especially with limited water availability. Inappropriate use of cover crops in this region can lead to economic losses on the farm. Successful and economically viable use of cover crops in the irrigated southwest will depend on the choice of cover crop, the cost of seeds, appropriate cover crop management, water availability and good timing of irrigation. Universally acceptable cover crop recommendations cannot be achieved within this region, but farm-specific recommendations based on the crop rotation, farm equipment available, and quantity and quality of water available can aid sustainable cover cropping in the Southwest.