Winter Cover Crops In A Corn-Forage Sorghum Crop Rotation System.

Cover Crops have proven to be beneficial to the production of field crops.  In the Central Plains, cover crops can contribute by increasing nitrogen and soil organic matter, and the establishment of soil cover.  This study focuses on using cover crops (winter wheat and austrian winter pea) in different rotations of corn and forage sorghum in Kansas (Manhattan, Tribune) to establish a ground cover, and to potentially work as a ‘catch’ crop to help reduce nitrogen loss through leaching and to potentially add nitrogen to the soil for use by corn and sorghum in the rotation(s).  Corn and forage sorghum were planted into plots, each with a randomly assigned 101 kg ha^-1 and 0 kg ha^-1 nitrogen treatment, and harvested for total biomass (grain and stover) at the end of the growing season.  Cover crops were then planted in the fall along with a fallow treatment into each of the plots, and then harvested for dry matter and terminated at corn and forage sorghum planting time(s) of the following year. Results indicated that the most significant effect came from the nitrogen treatment under all rotations for each crop.  In 2010, in Manhattan, the 101 kg ha^-1 nitrogen treatment produced as much as 42687 kg ha^-1 total forage sorghum biomass while the 0 kg ha^-1 nitrogen treatment produced as much as 36764 kg ha^-1.  In 2011, in Manhattan, forage sorghum total biomass peaked at 47976 kg ha^-1 with the 101 kg ha^-1 treatment.  With the 0 kg ha^-1 treatment, yields reached up to 38039 kg ha^-1.  Corn yields for the 101 kg ha^-1 treatment were up to 50742 kg ha^-1.  Under the 0 kg ha^-1 treatment, yields reached 39846 kg ha^-1.  In Tribune, with the 101 kg ha^-1 treatment, yields got up to 70259 kg ha^-1 for forage sorghum, while the 0 kg ha^-1 treatment yields made it up to 66938 kg ha^-1.  With Corn, yields reached 51027 kg ha^-1 under the 101 kg ha^-1 treatment. Where the 0 kg ha^-1 treatment was applied, yields were up to 42802 kg ha^-1.