Extending Greenseeker Technology to Bermudagrass Pasture Land.

The Greenseeker technology allows producers to estimate yield potential and obtain N fertilization rates recommendations from NDVI readings based on algorithms. Algorithms developed by Oklahoma State University are available as a free web-based tool: Sensor-Based Nitrogen Rate Calculator. The algorithms parameters for wheat, corn, and sorghum are considered very robust conferring accurate estimates for yield and N recommendations due to extensive multi-year/location data collection. Currently there is an algorithm developed for bermudagrass, however the data set is not robust enough for accurate N fertilization recommendations across a wide region.  Many agricultural extension educators showed a great interest in extending the reach of this technology.  Our objective was to collect extensive multi-year/location data in Oklahoma State for improving the existing bermudagrass algorithm. Bermudagrass plots with different nitrogen rates were set in five Oklahoma counties by their respective educator. Eastern half Oklahoma was represented in this study which includes most of the climate and soil variation within that part of the State. Nitrogen rates such as 0, 28, 56, 84, 112, 168 and 224 kg ha^-1 were applied late spring, NDVI reading collect every two weeks and biomass samples collect close to bermudagrass sward stage which agrees with hay harvesting period. Algorithm improvement based on the collected data will be presented.