Nitrogen Use Efficiency, Nitrogen Fertilizers, NUE, Nitrogen and the EnvironmentField Scale Variable Rate Trials, 2002, 2003, 2004, 2005
Resolution Trials, 3-Point Trials, 2004, 2005
3-Point Wheat Trials 2005

Table 1. Grain yield and nitrogen fertilizer applied for 2005 Wheat 3pt trial in EFAW, Lake Carl Blackwell and Tipton, OK.

Trt

Preplant N

Topdress N*

Total N Applied, lb ac-1

Grain Yield, bu ac-1

 

    lb ac-1

 

EFAW

LCB

Tipton

EFAW

LCB

Tipton

1

0

0

0

0

0

28

42

14

2

120

0

120

120

120

35

58

45

3

0

NFOA

26

28

24

32

43

21

4

45

NFOA

53

61

64

34

54

32

5

0

SBNRC

40

58

40

33

49

27

6

45

SBNRC

60

80

85

35

57

40

7

45

45

101

87

-

36

56

-

8

90

0

90

90

-

35

59

-

 

 

 

 

 

 

 

 

 

* UAN 28% N

Table 2. N Fertilizer, grain yield and profit for Wheat 3 pt trial in EFAW, LCB and Tipton.

 

 

EFAW

LCB

Tipton

Trt

Preplant

Topdress

Yield

Profit

Topdress

Yield

Profit

Topdress

Yield

Profit

 

lb ac-1

lb ac-1

bu ac-1

$

lb ac-1

bu ac-1

$

lb ac-1

bu ac-1

$

1

0

0

28

96

0

42

147

0

14

48

2

120

0

35

87

0

58

165

0

45

123

3

0

26

32

102

28

43

142

24

21

65

4

45

8

34

103

16

54

171

19

32

90

5

0

40

33

102

58

49

153

40

27

82

6

45

15

35

104

35

57

175

40

40

113

7

45

56

36

93

42

56

167

-

-

-

8

90

0

35

94

0

59

180

-

-

-


preplant N price lb-1 : $ 0.30
topdress N price lb-1 : $ 0.35
price of wheat bu-1 : $ 3.50

 

2005 OFIT
Table 1. N fertilizer applied for Wheat OFIT 2005 across sites, OK.

Trt

Preplant N

Topdress

Topdress N Applied, lb ac-1

 

lb ac-1

lb ac-1

Altus

Covington

Hennessey

Lahoma

LCB

Perkins

Tipton

1

0

0

0

0

0

0

0

0

0

2

0

Flat

45

45

45

45

45

45

45

3

0

Flat

90

90

90

90

90

90

90

4

45

Flat

45

45

45

45

45

45

45

5

45

0

0

0

0

0

0

0

0

6

90

0

0

0

0

0

0

0

0

7

0

NFOA-CV

46

34

86

34

15

12

35

8

45

NFOA-CV

20

17

44

18

8

4

29

9

0

SBNRC

32

24

77

0

9

22

37

10

45

SBNRC

2

9

26

34

11

13

29

11

0

0

0

0

0

0

0

0

0

12

0

MY-NFOA

51

33

125

33

28

26

56

13

45

MY-NFOA

18

27

21

27

12

21

37

 

 

 

 

 

 

 

 

 

 

 

Table 2. Grain Yield for Wheat OFIT 2005 across sites, OK.

Trt

Preplant N

Topdress

Grain Yield, bu ac-1

 

lb ac-1

lb ac-1

Altus

Covington

Hennessey

Lahoma

LCB

Perkins

Tipton

1

0

0

30

13

43

23

40

28

15

2

0

Flat (45)

35

20

50

39

42

30

26

3

0

Flat (90)

31

24

53

49

48

35

38

4

45

Flat (45)

28

21

55

53

43

31

37

5

45

0

29

18

53

30

44

32

24

6

90

0

29

19

51

46

44

35

27

7

0

NFOA-CV

33

19

50

37

41

30

28

8

45

NFOA-CV

31

19

56

45

41

33

35

9

0

SBNRC

32

16

54

37

42

33

25

10

45

SBNRC

30

18

54

49

41

33

34

11

0

0

32

12

47

26

41

27

18

12

0

MY-NFOA

34

19

51

43

44

32

31

13

45

MY-NFOA

29

22

52

51

43

29

33

 

 

 

 

 

 

 

 

 

 

Average CV

5%

20%

13%

20%

11%

16%

17%

CV range

3-8%

15-28%

7-24%

14-26%

7-18%

10-22%

10-23%

 Average RINDVI

1.14

1.33

1.46

1.95

1.23

1.24

1.78

Table 3. Profit earned for Wheat OFIT 2005 across sites, OK.

Trt

Preplant N

Topdress

Profit, $ ac-1

 

lb ac-1

lb ac-1

Altus

Covington

Hennessey

Lahoma

LCB

Perkins

Tipton

1

0

0

106

45

151

79

140

98

53

2

0

Flat

105

55

158

121

131

90

77

3

0

Flat

78

51

155

142

135

91

102

4

45

Flat

70

44

162

155

120

81

102

5

45

0

88

51

173

92

142

98

69

6

90

0

75

40

153

134

127

96

68

7

0

NFOA-CV

98

53

145

116

138

101

86

8

45

NFOA-CV

88

46

167

139

129

99

100

9

0

SBNRC

102

48

162

131

143

107

75

10

45

SBNRC

90

48

166

146

127

99

96

11

0

0

112

42

166

91

145

99

63

12

0

MY-NFOA

100

54

134

138

145

103

87

13

45

MY-NFOA

83

53

161

155

132

102

88

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 
3-Point Wheat Trials, 2004
Method of Application and Resolution Tipton, OK 2004
Treatment
PrePlant N
Topdress N
Grain Yield
N Use Efficiency
 
lb/ac
lb/ac
bu/ac
%
Check
0
0
50.5
---
Fixed Rate 1
90
0
69.8
30
Fixed Rate 2
0
90
70.3
31
Var. Rate 3 x3 ft
0
30
63.5
60
Var. Rate 6 x 12 ft
0
33
63.5
55
Var. Rate 12 x 24
0
31
60.9
47
Average check sensor CV = 17.2% with Average NDVI = 0.61 at Feekes 5
Method of Application and Resolution Chickasha, OK - 2004
Treatment
PrePlant N
Topdress N
Grain Yield
N Use Efficiency
 
lb/ac
lb/ac
bu/ac
%
Check
0
0
18.1
---
Fixed Rate 1
90
0
25.2
11
Fixed Rate 2
0
90
26.5
13
Var. Rate 3 x3 ft
0
30
24.2
24
Var. Rate 6 x 12 ft
0
33
25.4
23
Var. Rate 12 x 24
0
31
26.0
27
Average check sensor CV = 12.1% with Average NDVI = 0.28 at Feekes 5
GreenSeekerTM vs Conventional Treatments Lake Carl Blackwell, Stillwater, OK 2004
Treatment
Preplant N Rate
Topdress N Rate
Total N Applied
Wheat Yield
NUE
Gross Rev.
Add. Return
 
Lb/ac
Bu/ac
%
$/ac
Check
0
0
0
31.3
----
109.00
 
All N Pre
120
0
120
40.4
11
111.00
 
Var NFOA
0
22
22
40.8
60
137.00
24.00
Var. NFOA
45
8
53
40.1
23
127.00
 
Flat NFOA
0
30
30
38.5
34
127.00
 
Flat NFOA
45
14
59
40.5
22
127.00
 
NFOA OSU Nitrogen Fertilizer Optimization Alogrithm
Sensor CV at F5 = 16, NDVI = 0.4
Revenue computed with wheat priced at $3.50/bu
GreenSeekerTM vs Conventional Treatments Chickasha, OK 2004
Treatment
Preplant N Rate
Topdress N Rate
Total N Applied
Wheat Yield
NUE
Gross Rev.
Add. Return
 
Lb/ac
Bu/ac
%
$/ac
Check
0
0
0
22.5
----
79.00
 
All N Pre
120
0
120
34.7
20
107.00
 
Var NFOA
0
24
24
32.0
57
106.00
 
Var NFOA
45
11
55
35.4
32
110.00
 
Flat NFOA
0
26
26
27.6
28
90.00
 
Flat NFOA
45
12
57
39.4
42
123.00
16.00
NFOA OSU Nitrogen Fertilizer Optimization Alogrithm
Revenue computed with wheat priced at $3.50/bu
Sensor CV at F5 = 12  and NDVI = 0.3
GreenSeekerTM vs Conventional Treatments Orlando, OK 2004
Treatment
Preplant N Rate
Topdress N Rate
Total N Applied
Wheat Yield
NUE
Gross Rev.
Add. Return
 
Lb/ac
Bu/ac
%
$/ac
Check
0
0
0
49.1
----
172.00
 
All N Pre
120
0
120
60.5
13
181.00
 
Var NFOA
0
13
13
54.3
57
186.00
 
Var. NFOA
45
10
55
61.8
33
202.00
21.00
Flat NFOA
0
20
20
52.4
26
178.00
 
Flat NFOA
45
13
13
62.7
33
205.00
24.00
NFOA OSU Nitrogen Fertilizer Optimization Alogrithm
Sensor CV at F5 = 22% and Average NDVI = 0.5
Revenue computed with wheat priced at $3.50/bu
 
Field Winter Demonstrations of VRT Applicator
Covington, OK, Matt Steinert Farms (February 24, 2004)
Cherokee, OK, Kenneth Failes (February 26, 2004)
Redrock, OK, Martin Williams (March 3, 2004)

Table 1.  Grain yield response to N fertilizer applications using various different resolutions, Tipton, OK, 2004.

Treatment      Preplant N     Topdress N      Method              Yield          Grain          NUE, %
                     lb/ac              lb/ac                                            bu/ac          N uptake
________________________________________________________________________

1                   0                   0                      -                          50.5           71.2           -
2                   90                 0                      -                          69.8           98.4           30
3                   0                   90                    -                          70.3           99.1           31
4                   0                   30                    NFOA 3x3’        63.3           89.2           60
5                   0                   33                    NFOA 6x12’      63.5           89.5           55
6                   0                   31                    NFOA 12x24’    60.9           85.9           47
________________________________________________________________________
SED                                                                                      2.8 
CV from NDVI readings in the Check plots, Feekes 5: 17.2% (range: 13.6-24.2)
avg. NDVI at F5 sensing: 0.61
                    

 

Table 2.  Grain yield response to N fertilizer applications using various different resolutions, Chickasha, OK 2004.

Treatment      Preplant N     Topdress N      Method               Yield          Grain          NUE, %
                      lb/ac              lb/ac                                            bu/ac          N uptake
________________________________________________________________________
1                   0                   0                      -                          18.1           25.5           -
2                   90                 0                      -                          25.2           35.5           11
3                   0                   90                    -                          26.5           37.3           13
4                   0                   36                    NFOA 3x3’        24.2           34.1           24
5                   0                   45                    NFOA 6x12’      25.4           35.8           23
6                   0                   42                    NFOA 12x24’    26.0           36.7           27
________________________________________________________________________
SED                                                                                      2.3          
CV from NDVI readings in the Check plots, Feekes 5: 12.1% (range: 10.1-15.7)
avg. NDVI at F5 sensing: 0.28
                                
 

Assumptions, Based upon Clyde COOP Website Aug 5, 2003, Cash prices GS = GreenSeeker              
Price of wheat, $/bu PPN cost, $/lb N TDN cost, $/lb N              
3.15 0.19 0.25                
                   
                   
Cooperator Preplant N, lb/ac In-season N, lb/ac GS N, lb/ac Total applied N, lb/ac Yield, bu/ac Return, $/ac        
Apache Farmer 82 34 0 116 42 108.22        
Apache NRS 100 0 0 100 49 135.35        
Apache GS 0 0 37 37 46 135.65        
Claybaker Farmer 76 0 0 76 34 92.66        
Claybaker NRS 100 0 0 100 47 129.05        
Claybaker GS 0 0 37 37 48 141.95        
Ivan Peck Farmer 81 0 0 81 42 116.91   Check 48 151.2
Ivan Peck NRS 100 0 0 100 44 119.60        
Ivan Peck GS 0 0 38 38 52 154.30        
Scheiber 0 GS 0 0 35 35 32 92.05        
Scheiber 50 Farmer 109 0 0 109 44 117.89   Check 25 78.75
Scheiber 50 NRS 100 0 0 100 43 116.45        
Scheiber 50 GS 50 0 8 58 43 123.95        
Steve Clark Farmer 80 0 0 80 58 167.50   Check 49 154.35
Steve Clark NRS 160 0 0 160 64 171.20        
Steve Clark GS 20 0 38 58 58 169.40        
Steinert_C Farmer 74 0 0 74 54 156.04        
Steinert_C NRS 118 0 0 118 59 163.43        
Steinert_C GS 59 0 37 96 55 152.79        
Steinert_P Farmer 110 0 0 110 63 177.55   Check 58 182.7
Steinert_P NRS 183 0 0 183 63 163.68        
Steinert_P GS 60 0 23 83 63 181.30        
                   
Average Data PPN, lb/ac TDN, lb/ac GSN, lb/ac Total applied N, lb/ac Yield, bu/ac Return, $/ac        
Average Farmer 87.43 4.86 0.00 92.29 48.14 133.82        
Average NRS 123.00 0.00 0.00 123.00 52.71 142.68        
Average GS 19.86 0.00 35.00 54.86 50.57 146.78        
                   
N Tech Industries
Field Scale Variable Rate Trials, 2002
Average over 10 Locations
Average over 10 sites            
      RIHARVEST = 1.31      
    Preplant Early Late Total N Yield Net Revenue
n= Treatment N rate, lb/ac Topdress N Topdress N rate, lb/ac bu/ac $/ac
             
33 2XS 62 32 0 94 44.6 116
81 VRT 41 15 23 79 39.8 104
24 VS3 35 21 35 91 37.3 93
25 VS2 49 9 24 82 35.4 91
17 Farmer Check 52 21 20 92 34.6 86
SED           3.1 9.5
             
             
***10 loc's              
81 VRT 41 15 23 79 39.8 104
17 Farmer Check 52 21 20 92 34.6 86
             
***5 loc's              
52 VRT 55 13 17 85 39.8 104
25 VS2 49 9 24 82 35.4 91
             
***5 loc's              
48 VRT 43 24 24 91 39.2 99
23 VS3 35 21 35 91 37.9 95
             
***8 loc's              
33 VRT 42 18 23 84 41.2 107
71 2XS 62 32 0 94 44.7 117
             
Net revenue = (grain yield * $3.00/bu) - (preplant N applied * $0.15/lb N)-(topdress N applied * $0.25/lb N)
SED = standard error of the difference between two equally replicated means
*** Means for only those sites where both treatments were evaluated (not all treatments were evaluated at each site)
By - Site Grain Yields
Cherokee, OK, Kenneth Failes RI NDVI = 1.1 Harvest Date, June 4, 2002
CV = 16     RI Harvest = 1.24
Treatment Description Preplant N Topdress N Total N Rate Yield
  lb/ac lb/ac lb/ac bu/ac
 
1 Flat NFOA 30 25 55 34
2 2X Strip 60 0 60 51
3 Flat NFOA 30 23 53 37
4 VRT 30 20 50 44
5 Check 30 0 30 41
6 2X Strip 60 0 60 42
7 75 Flat 30 75 105 43
8 VRT 30 20 50 30

 

Amorita, OK, Steve Clark   RI NDVI = 1.46 Harvest Date: June 12, 2002
CV = 18
RI Harvest = 1.36
  Preplant Topdress Total N Yield
Reps Treatment N rate, lb/ac N rate, lb/ac rate, lb/ac bu/ac
 
2 2X Strip 92 0 92 57.4
1 Check 46 0 46 42.2
2 Flat NFOA-45 46 45 91 44.7
3 VRT 46 41 87 49.2
1 Flat NFOA-75 46 75 121 50.2
1 Farmer 46 30 76 40.3
 
Earl Marshall, Hennessey RISV = 1.55 Harvest Date: June 18, 2002
CV = 20    Preplant Topdress Total N Yield
Reps Treatment N rate, lb/ac N rate, lb/ac rate, lb/ac bu/ac
           
4 VRT 75 31 106 29.9
4 FLAT NFOA 75 25 100 26.3
4 VRT 75 35 110 28.2
4 FLAT NFOA 75 28 103 23.1
 
      RINDVI = 1.57    
Matt Steinert - Emerson RIHARVEST=1.1 Harvest Date: June 19, 2002
CV = 26
Preplant Topdress Topdress Total N Yield
Reps Treatment N rate, lb/ac N rate, lb/ac N rate lb/ac rate, lb/ac bu/ac
Jan 12 April 3
4 2X Strip 10 100 0 110 29
4 Check 10 0 0 10 26
4 Flat NFOA 10 50 37 97 37
4 75 Flat 10 50 62 122 38
4 VRT 10 50 38 98 38
4 Flat NFOA 10 50 34 94 36
4 VRT 10 50 45 105 42
Average of Flat NFOA 36.5        
Average of VRT 40.0
 
      RINDVI = 1.27    
Matt Steinert - Peters   RIHARVEST=1.34 Harvest Date: June 19, 2002
CV=18            
    Preplant Topdress Topdress Total N Yield
Reps Treatment N rate, lb/ac N rate, lb/ac N rate lb/ac rate, lb/ac bu/ac
    Jan 12 April 3    
4 2X Strip 10 100 0 110 44.8
4 Check 10 0 0 10 33.3
4 Check 10 50   60 34.2
4 Flat NFOA 10 0 21 31 34.6
4 Flat NFOA 10 50 57 117 44
4 VRT 10 50 14 74 42.8
           

 

      RINDVI = 1.43    
Matt Steinert - Beopple RIHARVEST=1.24 Harvest Date: June 20, 2002
CV = 21
  Preplant Topdress Topdress Total N Yield
Reps Treatment N rate, lb/ac N rate, lb/ac N rate lb/ac rate, lb/ac bu/ac
  Jan 12 March 28
4 2X Strip + VRT 10 60 39 109 47.8
4 2X Strip 10 60 0 70 53.5
4 4X Strip + VRT 10 120 0 130 46.8
4 4X Strip + VRT 10 120 43 173 47.6
4 Check 10 0 0 10 43.2
4 Check + VRT 10 0 31 41 49.4
4 Flat NFOA 63 10 30 23 63 48.1
4 Flat NFOA 91 10 30 51 91 48.7
4 VRT 72 10 30 32 72 46.9

 

Stan Claybaker   RINDVI = 1.1 Harvest Date: June 24, 2002
    RIHARVEST = 1.1    
CV = 15          
    Preplant Topdress Total N Yield
  Treatment N rate, lb/ac N rate, lb/ac rate, lb/ac bu/ac
    11-Apr-02    
4 VRT 56 10 66 43.3
4 VRT 56 10 66 42.3
4 VS1 56 9 65 40.7
4 VRT 56 11 67 41.9
4 VS2 56 23 79 40.5
4 VS5 56 54 110 42
4 2XStrip 106 0 106 44.2
4 2XStrip+VS5 106 55 161 44.2

 

Tom Cannon     RINDVI = 1.33 Harvest Date: June 24, 2002
      RIHARVEST = 1.1  
CV = 13          
    Preplant Topdress Total N Yield
  Treatment N rate, lb/ac N rate, lb/ac rate, lb/ac bu/ac
    11-Apr-02    
4 OPTICROP 15 60, 40 115 39.1
4 Check 45 0 45 36.8
4 VRT 45 43 88 37.5
4 VS3 45 31 76 37.5
4 VRT 45 35 80 38.9
4 VS3 45 30 75 38.8
4 2XS VRT 85 40 125 38.8
4 2XS 85 0 85 38.3

 

Otto Matusek     RINDVI = 1.1 Harvest Date: June 25, 2002
        RIHARVEST = 1.3  
CV=47            
    Preplant Topdress Topdress Total N Yield
  Treatment N rate, lb/ac N rate, lb/ac N rate, lb/ac rate, lb/ac bu/ac
    10-Dec-02 3-Apr-02    
4 2XS 150 28 0 178 48.64
4 VS3 75 28 36 139 39.8
4 VRT RI 1.5 75 28 13 116 44.5
4 VS1 75 28 11 114 37.2
4 VRT RI 1.1 75 28 3 106 39.1
4 VS2 75 28 25 128 40.2
4 VRT RI 1.3 75 28 11 114 40.7
4 VRT RI 1.1 75 28 4 107 38.8
4 VRT RI 1.3 75 28 8 111 40.7
4 VS1 75 28 12 115 36.7
4 check 75 28 0 103 37.1

 

Efaw Exp. Station   RINDVI = 1.65 Harvest Date: June 26, 2002
      RIHARVEST = 1.27  
CV = 35          
    Preplant Topdress Total N Yield
  Treatment N rate, lb/ac N rate, lb/ac rate, lb/ac bu/ac
    27-Mar-02    
6 VRT 0 21 21 31.7
2 VS3 0 44 44 31.7
4 VS5 0 62 62 31.1
4 check 0 0 0 24.5
Comprehensive information on Nitrogen Use Efficiency for cereal crop production
N Tech Industries