No-Tillage Increases Profit in a Limited Irrigation-Dryland System

Abstract

Furrow irrigation is used on about 50% of the 22 million irrigated acres in the Great Plains. Irrigation water is pumped from the Ogallala aquifer and is in limited supply in relation to available land. Research has greatly improved irrigation water use efficiency since the mid 50s. The most recent and efficient system of furrow irrigation is Limited Irrigation-Dryland (LID) in which tailwater and rainfall runoff are almost eliminated using a combination of furrow dikes and irrigating only the top two-thirds of a field. Our objective was to compare effectiveness of conventional tillage, furrow diking, and no-tillage in fallow periods and crops in a winter wheat (Triticum aestivum L)-sorghum [Sorghum bicolor (L.) Moench.]-fallow crop rotation using a LID system of irrigation. No-tillage increased soil water storage during fallow periods compared with conventional tillage and furrow diking. This in turn increased sorghum yield 400 lb/acre as well as irrigation water use efficiency for sorghum. Wheat yield was not improved with no-tillage because of poor stands. Short-term variable costs with no-tillage were less than for furrow diking or conventional tillage. Annual profits for conventional tillage, furrow diking, and no-tillage were $66, 63, and 75/acre. This research showed that using no-tillage is better than narrow diking in a winter wheat-sorghum-fallow rotation using a LID irrigation system.