2012 Annual Report 1a.Objectives (from AD-416): 1) Develop best management practices (BMPs) for sustainable large-scale establishment and production of feedstocks. 2) Enhance diversity, productivity, and resiliency through development of mixed species bioenergy production systems. 1b.Approach (from AD-416): Field-scale research plots will be established at Woodward, OK, to evaluate best warm-season grass establishment method and nitrogen requirements. Monocultures as well as mixed-cultures of grasses will be studied with commercial and legume nitrogen management methods. 3.Progress Report: Ongoing experiments at the Woodward, Oklahoma, USDA-ARS location include: (Experiment. 1)response of dedicated bioenergy species to nitrogen, (Experiment. 2)effect of perennial grass species composition on biomass production, and (Experiment. 3)screening new switchgrass populations for biomass production. Each year a high-biomass sorghum is planted for annual crop biomass estimates. Some plots of switchgrass and mixed grasses were replanted or over-seeded to thicken stands. All plantings were carried out under no-till conditions. Soil samples were collected in Experiment 2 for spatio-temporal variability analysis. Different nitrogen treatments were established in all species and all plots. In season biomass samples were collected at monthly intervals. Spectral data using ASD spectroradiometer and Green Seeker were developed for switchgrass and sorghum to detect nitrogen concentration and biomass quantity. Dry material from the biomass samples was used to develop spectral signatures for biomass quality analysis. Final biomass was collected from plots using a swather and square/round baler. Data collected from multiple locations is being tabulated using an Excel database and analyzed. The experiments are expected to continue until fall 2014.