With increasing planting densities,dry matter content of the residual by-products after harvesting of the fresh ear decreases first and then increases considerably.Contents and productions of crude fat,nitrogen free extract,crude fiber and production of total digestible nutrients increase remarkably;content and production of CP are the highest when it's medium planting density;densities do not affect the content of crude ash conspicuously.With increasing level of applied nitrogen,productions of dry matter,n...