Cover Crops Impact on Soil Water Storage in Dual Purpose Wheat Systems.

Abstract

Partson Mubvumba¹, Paul DeLaune² and Bill Coufal². ¹Texas A&M University, Soil & Crop Sciences, College Station, TX and  ²Texas A&M AgriLife Research, Texas A&M University, Vernon, TX.

Cover crops impact on soil water storage in dual purpose wheat systems

Continuous wheat production for grain and grazing is a common practice in the southern Great Plains. Monoculture practices are detrimental to soil quality and depletion of nutrients. Adoption of conservation systems has been hampered by perceived soil compaction in no-till under dual purpose production systems. Cover crops and conservation tillage practices can improve soil health. However, cover crops and soil moisture use is a top concern in semi-arid environments. This study was established to evaluate and quantify the impact of cover crops in dual-purpose no-till wheat on soil chemical, physical, soil moisture and crop growth in Texas Rolling Plains. Specifically this presentation evaluates the impact of cover crops on soil water dynamics in dual purpose wheat systems. The study was randomized complete block design with four treatments replicated four times. The treatments were conventional tillage, No-tillage, No tillage with Cover crops and Grazing and No tillage with Cover crops and No Grazing. A neutron probe was used to measure soil water storage once every two weeks at 20cm depth increments to 140 cm. Currently cover crops are showing significantly less soil water storage at time of termination each year.  Summer 2014 cover crops showed soil moisture replenishment. Subsurface (30-140cm) soil moisture storage for May, June and July 2014 months recorded lowest for no cover (conventional tillage) and highest for no till cover no graze treatment. No tillage with Cover crops and Grazing recorded least soil moisture storage. Cover crops and no tillage practices are showing potential benefits in the long term.