Wednesday, November 15, 2006

Bermudagrass Nitrogen Timing and In-Season Rate Determination.

Jeffrey Ball1, Jagadeesh Mosali2, Shawn Norton1, Frank Motal3, and Billy Cook3. (1) The Noble Foundation, PO Box 2180, Ardmore, OK 73402-2180, (2) TheNoble Foundation, 1208 Holly St, Ardmore, OK 73401, (3) Noble Foundation, 2510 Sam Noble Pkwy, Ardmore, OK 73401

As new fertilizer application technologies emerge, evaluation of new products and programs is necessary.  A new optical sensor based variable nitrogen (N) rate application system has been developed by Oklahoma State University and N-Tech Industries. Traditional N fertilizer management for bermudagrass production plans an early spring application and additional N after each cutting.  Rates are generally based on past production history and yield goals.  This approach does not take into account the status of the growing crop at the time of application.  The sensor-based approach will use the spectral signature of the growing crop to integrate stress and growing environment conditions into N fertilizer needs. The objectives of this research are to evaluate the response of bermudagrass to sensor based variable nitrogen rate applications, validate the current fertilization rate algorithm, and compare this program to traditional N fertilization strategies.