1. EVOLUTION OF NITROGEN REFERENCE STRIPS

2. HISTORY
1563
Huganote Bernard Palissy advocates the use of fertilizers in agriculture to stimulate plant growth
Did so after noticing that crops tended to have better production where manure had been applied

3. HISTORY 1772 1790 Daniel Rutherford discovers nitrogen
French chemist Jean-Antoine-Claude Chaptal coins the name ‘nitrogen’ using a combination of Greek and French words meaning “to engender, bring forth”

4. HISTORY 1827 Justus Liebig’s famous Mineral Theory.
The Mineral Theory states that plant growth is limited by the most limited available mineral in the soil. The application of this theory led to the development of mineral fertilizer.

5. HISTORY
1913
The process that would become known as the Haber-Bosch process was developed by Fritz Haber and Carl Bosch.
The process was the first industrial chemical process to use high pressure for a chemical reaction.
This process is the most economical for the fixation of nitrogen and continues to this day
This process would help usher in the Green Revolution

6. FERTILIZER APPLICATIONS
Since the introduction of synthetic fertilizers, inaccurate fertilizer rates (either too much or too little) have been applied.
This is the result of failing to recognize temporal variability.

9. Crop production directly related to availability of N
RESULT
Nitrogen Use Efficiency (NUE) in the world for cereal grain production ~ 33%
Crop production directly related to availability of N
Need methodologies that consider:
Crop production practices
Every Farmer is different
Aesthetic qualities
The crop has to look good
Economical analysis
The bottom line is what counts
Environmental stewardship
Pollution costs everyone

10. EXAMPLE Fueling a Tractor 90 gal 30 gal 60 gal John Deere 7810
90 gal. Fuel Tank
~ $270
90 gal
30 gal
60 gal

11. EXAMPLE Only Needed 45 gal Fueling a Tractor 90 30 60
Over-filled 45 gal (lost)
Cost ~ $270
Money lost ~ $135
Fueling a Tractor
John Deere 7810
90 gal. Fuel Tank
~ $270 90
gal 30
gal 60
gal

12. EXAMPLE Needed 0 gal Fueling a Tractor
Over-filled 90 gal (lost)
Cost ~ $270
Money lost ~ $270
Fueling a Tractor
John Deere 7810
90 gal. Fuel Tank
~ $270
60 gal
30 gal
90 gal
The Fuel Gauge is our reference to how much fuel is in the tank. We can add accordingly.

13. GAUGE FOR NITROGEN IN OUR FIELDS?
Can there be such a thing?
If so, how?
THE ANSWER……..
Nitrogen Reference Strips
N-Stamp, N-Rich Strip, N-Ramp

14. NITROGEN REFERENCE STRIP
An indicator that orients the producer to the nitrogen levels within the field to aid in making a better mid-season nitrogen rate recommendation.
Superimposed on existing farmer pre-plant practices
Provides a measure of how much additional N is needed, if any
Minimizes risk

15. NITROGEN RICH STRIP – 2002 – Present
1 N rate – In excess of what is required by the plant for the entire growing season.
Answers the question – Do I need to apply any additional N fertilizer?
YES or NO
With GreenSeeker sensor and SBNRC can obtain RI, predict yield potential, and determine optimum N rate for maximum yield

16. NITROGEN CALIBRATION STAMP – 2004-2005

17. NITROGEN RAMP CALIBRATION STRIP – 2006 – Present

18. Ramp Calibration Strip Fertilization Strategy – 2006 – Present
Concept of visually evaluating plots with incremental rates of pre-plant N
Identify minimum N rate required for maximum production

20. March 2007, The Furrow, Larry Reichenberger

21. N-Reference Strip methodologies consider:
Crop production practices
Every Farmer is different
Aesthetic qualities
The crop has to look good
Economical analysis
The bottom line is what counts
Environmental stewardship
Pollution costs everyone

22. The N-Reference Strip Approach:
CONCLUSIONS
Current practices for making mid-season fertilizer N recommendations in most crops are not consistent from one region to the next
The N-Reference Strip Approach:
Uses 1 rate or a gradient of pre-plant N fertilizer to determine mid-season N rates based on plant response
Applied methodology integrating farmer input and insight in the decision making process
Provides visual mid-season alternative approach for N fertilization

23. EXAMPLE When Empty: 90 gal Fueling a Tractor
Over-filled 0 gal ( 0 gal lost)
Cost ~ $270
Money lost ~ $0
ONLY PUT IN WHAT IS NEEDED!
Fueling a Tractor
John Deere 7810
90 gal. Fuel Tank
~ $270
90 gal
30 gal
60 gal

24. EXAMPLE When Half-Full: 45 gal Fueling a Tractor
Over-filled 0 gal ( 0 gal lost)
Cost ~ $135
Money lost ~ $0
ONLY PUT IN WHAT IS NEEDED!
Fueling a Tractor
John Deere 7810
90 gal. Fuel Tank
~ $270 30
gal 45
gal

25. EXAMPLE When Full: 0 gal Fueling a Tractor ONLY PUT IN WHAT IS NEEDED!
Over-filled 0 gal (0 gal lost)
Cost ~ $0
Money lost ~ $0
ONLY PUT IN WHAT IS NEEDED!
Fueling a Tractor
John Deere 7810
90 gal. Fuel Tank
~ $270
0 gal
The Fuel Gauge is our reference to how much fuel is in the tank. We can add accordingly.

26. LIKEWISE… N-REFERENCE STRIPS
OUR GAUGE TO THE NITROGEN LEVEL IN THE FIELD
OUR GAUGE TO IDENTIFY HOW MUCH ADDITIONAL NITROGEN, IF ANY, IS NEEDED BY THE CROP TO PRODUCE MAXIMUM YIELDS.

27. EXTENSION AND ANALYSIS OF THE RAMP CALIBRATION STRIP FERTILIZATION STRATEGY

28. Crop production directly related to availability of N
INTRODUCTION
Nitrogen Use Efficiency (NUE) in the world for cereal grain production ~ 33%
Crop production directly related to availability of N
Need methodologies that consider:
Crop production practices
Aesthetic qualities
Economical analysis
Environmental stewardship

29. Ramp Calibration Strip Fertilization Strategy
Concept of visually evaluating plots with incremental rates of pre-plant N
Identify minimum N rate required for maximum production

32. RAMP Calibration Strip
N Rate, kg/ha
224 34 17
224

33. March 2007, The Furrow, Larry Reichenberger

34. PURPOSE OF STUDY 2007 Intentions
Implement & Evaluate the RCS strategy in the following crops:
Alfalfa
Bermudagrass
Corn
Cotton
Grain Sorghum
Extend the RCS strategy in the following crop:
Wheat

35. MATERIALS & METHODS Alfalfa, Grain Sorghum Alfalfa Grain Sorghum
Experiment site – R.L. Westerman Irrigation Research Center located west of Stillwater, OK.
Alfalfa, Grain Sorghum
4 replications of 5 treatments + 1 or 2 N-Ramp(s)
Complete Randomized Block Design
Alfalfa
Trt.
N applied after each cutting (kg ha-1) 1.
(0 lb N/Ac) 2.
(20 lb N/Ac) 3.
(40 lb N/Ac) 4.
RCS Visual 5.
RCS Sensor
Grain Sorghum
Trt.
Pre-Plant N (kg ha-1)
Mid-Season N (kg ha-1) 1.
56 (50 lb N/Ac)
(0 lb N/Ac) 2.
84 (75 lb N/Ac) 3.
168 (150 lb N/Ac) 4.
RCS Visual 5.
RCS Sensor

36. (N applied mid-season)
Treatments
(N applied mid-season) 1.
0 kg N/ ha 2.
84 kg N/ ha 3.
168 kg N/ ha 4.
RCS Visual 5.
RCS Sensor
Grain Sorghum Application of N-Ramp Strategy R.L. Westerman Irrigation Research Center at Lake Carl Blackwell
15.25 m
3 m
6 m
1.5 m
52 m
4.25 m
Rep. 1
Rep. 2
Rep. 3
Rep. 4 6
7.5
13.5 15 21
22.5
28.5 3 9 12
29 m N - R A M P 4 1 3 5 2 N E S W 4 5 2 3 1 4 1 3 5 2
Plot size: 3 m x 6 m
Alley: 1.5 m
4 replications
Ramp: 4.25 m x 52 m 2 4 5 3 1

37. ALFALFA – RESULTS Alfalfa Inconclusive for 2007 Average Yields
Limited number of cuttings
Average Yields
1st Cutting
5607 kg ha-1 (5000 lb Ac-1)
2nd Cutting
3734 kg ha-1 (3330 lb Ac-1)
Alfalfa
Trt.
N applied after each cutting (kg ha-1) 1. 2.
22.4 3.
44.8 4.
0 - RCS Visual 5.
0 - RCS Sensor

38. GRAIN SORGHUM – RESULTS
Average Yields
Grain Sorghum
Trt.
Pre-Plant N
(kg ha-1)
Mid-Season N (kg ha-1)
Total N
Yield
Gross Return
($ ha-1) 1.
56 (50 lb N/Ac)
(0 lb N/Ac)
56 (50)
2776 (2475)
($118 / Ac) 2.
56 (50 lb N/Ac)
(75 lb N/Ac)
140 (125)
5033 (4488)
($198 / Ac) 3.
168 (150 lb N/Ac)
224 (200)
6166 (5499)
($222 / Ac) 4.
(65 lb N/Ac)
RCS Visual
129 (115)
4783 (4265)
($190 / Ac) 5.
56 (50 lb N/Ac)
RCS Sensor
112 (100)
5370 (4789)
($227 / Ac)
Gross Return: N cost = $1.01 / kg, Sorghum = $0.125 / kg
$0.46 / lb $0.057 / lb

39. WHEAT – EXTENSION OF N-RCS APPROACH Recap
Fall 2006
N-Ramps placed in 586 farmer fields throughout Oklahoma covering a service area of 81,000 hectares (200,000 Acres)

40. Garfield County Ramp Strips
March 22, 2007

41. February/March 2007 County Extension Agents Sensed N-Ramps
Provided top-dress N recommendations to producers
Collected data for submission to N-Ramp extension team

42. EXTENSION OF N-RCS APPROACH IN WHEAT – RESULTS
Average Typical Top-Dress N Rate
125 kg N / ha (110 lb N/Ac)
Average RCS N-Recommendation
60 kg N / ha (53 lb N/Ac)
Average Actual Top-Dress N Applied
90 kg N / ha (80 lb N/Ac)
50 % more than the RCS recommendation
73 % of typical top-dress N rate
Represents savings of $ ha ($13.80 Ac-1)
Represents total savings of $ 2,760,000

43. WHEAT – EXTENSION OF N-RCS APPROACH
Fall 2007
N-Ramps or N-Rich Strips placed in 224 farmer fields throughout Oklahoma

44. CONCLUSIONS
Current practices for making mid-season fertilizer N recommendations in most crops are not consistent from one region to the next
The N-Ramp Approach:
Using automated gradients of pre-plant N fertilizer to determine mid-season N rates based on plant response
Applied methodology integrating farmer input and insight in the decision making process
Provides visual mid-season alternative approach for N fertilization