

Regional Trial Data Will Be Public VIA the NUE
Web Site Questions Concerning the Regional Trial Can be Addressed To:
Newell R. Kitchen
Robert Mullen
Bill Raun Data to be Collected at ALL Sites, and from all Plots
NDVI, V6, V8, V10, V12 P and K applied preplant to local
sufficiency levels 

Regional Trial 2006  
At the end of the season, algorithms will be evaluated to determine which ones predicted the optimum N rate, and the deviation from the optimum rate. A. At the time topdress N is applied (between V8 and V10), each collaborating entity (e.g., OSU, UNL, USDAARSMissouri, etc.) will have the opportunity to submit the N rate they deem to be the optimum (using either the NDVI, Chlorophyll, or soil test data). Predicted N rates from each institution will be posted on the web site. Actual rates to be applied by each collaborating institution will not be necessary using the treatment structure above, since a response curve will be determined at each site, that will establish apriori the optimum N rates (both max yield and economic). B. Once grain yield data has been compiled, data will be forwarded to Robert Mullen who has agreed to tabulate the entire data base for combined analysis. However, everyone who wants access to the raw data can do so. C. It is imperative that all data be collected at each site (noted above) so that this group can establish what algorithms are working where, and why.  Method of Application: 1. Nitrogen SufficiencyUSDAARS, UNL a. Minolta SPAD meter readings collected
from treatment 2 (t2) and treatments 7 (t7) and 8 (t8) Comments: note the Response Index will be different for treatment 9 and 10, because the N Rich Strip is divided by the NDVI value in these respective treatments. In general, you should expect less topdress N to be applied topdress in treatment 10 versus treatment 9. Details on how the N rate is calculated (step h) are available at http://www.nue.okstate.edu/RI_CV_Discussion.htm An excel file that can be used in the field with your PDA (does everything the SBNRC does) .... follow this link (EXCEL file) 3. Missouri Instructions for VR N Using ActiveLight Sensors: Missouri 2004 version For this algorithm, you’ll be using the ratio of the visible to NIR (i.e., VIS/NIR). IN each case where VIS/NIR is included below, this is the simple ratio (last output value on the GreenSeeker sensor). SR = (VIS/NIR) Collect sensor reflectance readings on treatments 2, 11, and 12 (t2, t11, and t12) sometime between V8 and V10 (preferably closer to V10) at approximately 53 cm above the height of the corn canopy. Treatments t11 and t12 are designated as the “target”, and treatment t2 is designated as the “reference.” Calculate the N rate for t11 and t12 as follows: N rate (lbs/acre) = 200 + 250 x [ VIS/NIR(target) / VIS/NIR(reference). Using this equation, corn that looks exactly like the reference will still receive 50 lbs N/acre. Apply N as close in time to when senor readings are taken as possible. N source and placement methods should follow the same procedure as the listed for the other treatments being tested 4. Virginia Follow guidelines in the online spreadsheet.
 


