Enhancing Sustainable Cropping Systems through the Use of Cover Crops.

            No-till increases the potential to crop more frequently in the Southern Great Plains compared to the conventional till crop-fallow system.  More frequent cropping requires nitrogen input to maintain economical yields.  Cover crops can be used at various parts of the year when a main crop is not being grown.

The objective of this experiment is to evaluate the effects of the use of cover crops as well as evaluating different nitrogen management strategies in a no till cropping system.

 Field studies were established near Lahoma, OK to evaluate the use of cover crops in a successful crop rotation.  The experimental design is a split plot with the main plots being crop rotation and the sub plots being nitrogen management.  Crop rotations include winter wheat, grain sorghum, corn, soybean, sunflower, cowpea, and Austrian winter pea.  Nitrogen management treatments include 1) N-rich (non-limiting), 2) typical farmer practice, 3) Green-seeker based, and 4) 0 lb N ha-1.

Including a legume cover crop has reduced nitrogen application rates.  In addition, by using Green Seeker ™ technology, nitrogen application rates were reduced 0 to 40% depending on the crop and the rotation. Including legume cover crops and utilizing optical sensor technology can greatly increase NUE.