1. EVALUATION OF OPTICAL SENSOR BASED NITROGEN ALGORITHMS FOR CORN USING SIDEDRESS LIQUID APPLICATIONS Robert Mullen, Greg Schwab, Wade Thomason, William Raun, James Schepers, Newell Kitchen, John Shanahan, Dennis Francis, Steve Phillips, Kyle Freeman, Paul Hodgen, Brian Arnall, Roger Teal, Clayton Dygert, Gyles Randall, and Jeff Vetsch Fluid Fertilizer Foundation Forum February 14, 2006 Robert Mullen, Greg Schwab, Wade Thomason, William Raun, James Schepers, Newell Kitchen, John Shanahan, Dennis Francis, Steve Phillips, Kyle Freeman, Paul Hodgen, Brian Arnall, Roger Teal, Clayton Dygert, Gyles Randall, and Jeff Vetsch Fluid Fertilizer Foundation Forum February 14, 2006

2. Experimental Results – Western Ohio Treatment Starter N Sidedress N (avg) Total N (avg) YieldReturn -------------------------------lb/acre-----------------------------------bu/acre-------$/acre---- 1000102204 22000200168276 Sidedress Avg 40124164159269 7 (OSU) 04444141269 8 (OSU) 403575138254 9 (UNL) 0162162152255 10 (UNL) 40132172166280 11 (MU) 0180180175296 12 (MU) 40142182139223 13 (VPI) 06666120220 14 (VPI) 4073113151268 LSD 0.1 33

3. Experimental Results – Wooster, OH Treatment Starter N Sidedress N (avg) Total N (avg) YieldReturn -------------------------------lb/acre-----------------------------------bu/acre-------$/acre---- 1000129258 22000200174288 Sidedress Avg 4084124165293 7 (OSU) 099130257 8 (OSU) 401050153291 9 (UNL) 0160160170292 10 (UNL) 40178218140215 11 (MU) 0165165156263 12 (MU) 40125165160271 13 (VPI) 05959159300 14 (VPI) 4063103153275 LSD 0.1 24

4. Experimental Results - Oklahoma Treatment Starter N Sidedress N (avg) Total N (avg) YieldReturn -------------------------------lb/acre-----------------------------------bu/acre-------$/acre---- 1000149298 22000200226392 Sidedress Avg 40137177215377 7 (OSU) 02727174340 8 (OSU) 403272221420 9 (UNL) 0110110201369 10 (UNL) 4060100215400 11 (MU) 05050186357 12 (MU) 405090218409 13 (VPI) 05151176337 14 (VPI) 405191224421 LSD 0.1 42

5. Experimental Results - Nebraska Treatment Starter N Sidedress N (avg) Total N (avg) YieldReturn -------------------------------lb/acre-----------------------------------bu/acre------$/acre--- 1000151302 22000200253446 Sidedress Avg 40158198242425 7 (OSU) 09393204380 8 (OSU) 4080120213390 9 (UNL) 0150150221397 10 (UNL) 40120160237426 11 (MU) 0160160217386 12 (MU) 4077117232429 13 (VPI) 06161201384 14 (VPI) 4062102217403 LSD 0.1 26

6. Experimental Results - Virginia Treatment Starter N Sidedress N (avg) Total N (avg) YieldReturn -------------------------------lb/acre-----------------------------------bu/acre-------$/acre---- 1000142284 22000200135210 Sidedress Avg 404040145278 7 (OSU) 01111134265 8 (OSU) 402565153287 9 (UNL) 08383146267 10 (UNL) 402868131242 11 (MU) 05454123230 12 (MU) 403979151278 13 (VPI) 04040124236 14 (VPI) 403979143262 LSD 0.1 24

7. Concerns Timing – how early can we reliably identify N need –V10 is going to be difficult for producers in dryland production –Challenges of soil reflectance early in the growing season Establishment of reference strip –Communication with co-op/retailer Timing – how early can we reliably identify N need –V10 is going to be difficult for producers in dryland production –Challenges of soil reflectance early in the growing season Establishment of reference strip –Communication with co-op/retailer

8. Potential for Technology Increases as N cost increases Environmental concerns –Governmental support Field evidence shows we can show a benefit –More work needed to identify what the right approach is Increases as N cost increases Environmental concerns –Governmental support Field evidence shows we can show a benefit –More work needed to identify what the right approach is

9. Research Will Continue! Already have an experimental design established for the upcoming year

10. Thanks!!!! Thanks to the Fluid Fertilizer Foundation for support!!! Questions???? Robert Mullen – mullen.91@osu.edu Thanks to the Fluid Fertilizer Foundation for support!!! Questions???? Robert Mullen – mullen.91@osu.edu