Improving NUE Using Crop Sensing:Improving NUE Using Crop Sensing:
“It Takes a Village”“It Takes a Village”
Handheld Sensing: Does User Have An Effect?
Handheld Sensing: Does User Have An Effect?
A Simple Test• Two 30-ft row segments were measured
by 4 different users
• Orientation: 1. E-W 2. N-S
• Both GreenSeeker (red) and Crop Circle ACS-210 sensors evaluated
• Replicated 5 times
• Corn was at ~ V-9 growth stage
• All users were given the same user instructions:– Hold sensor between 20 and 24 inches above
the crop canopy– Keep the sensor centered over the row as
much as possible– Keep the sensor level as possible (by eye)– Walk about 1 to 2 miles/hr– Collect data between the flags
A Simple Test
NDVI
0.60.620.640.660.68
0.70.720.740.760.78
0.80.82
GreenSeeker Crop Circle
User 1 User 2 User 3 User 4
b
d
a
c
c
a ab
NDVI sd
00.01
0.020.03
0.040.05
0.060.07
0.080.09
0.1
GreenSeeker Crop Circle
User 1 User 2 User 3 User 4
a
b bb
b
a
ba
Number of Measurements
0
50
100
150
200
250
300
GreenSeeker Crop Circle
User 1 User 2 User 3 User 4
a
c
ab
c
ba
b
NDVI
0.60.620.640.660.680.7
0.720.740.760.780.8
0.82
GreenSeeker Crop Circle
User 1 User 2 User 3 User 4
b
d
a
c
c
a ab
0.60.620.640.660.680.7
0.720.740.760.780.8
0.82
GreenSeeker Crop Circle
User 1 User 2 User 3 User 4
b
d
a
c
c
a ab
Number of Measurements
0
50
100
150
200
250
300
GreenSeeker Crop Circle
User 1 User 2 User 3 User 4
a
c
ab
c
ba
b
0
50
100
150
200
250
300
GreenSeeker Crop Circle
User 1 User 2 User 3 User 4
a
c
ab
c
ba
b
• One user repeated the sensor measurements (Crop Circle only) walking in the opposite direction as the initial test.
A Simplier Test
NDVI
0.65
0.660.66
0.670.67
0.680.68
0.690.69
0.700.70
Crop Circle
Direction 1 Direction 2
a
a
Number of Measurements
210
215
220
225
230
235
240
Crop Circle
Direction 1 Direction 2
a
b
Handheld Sensing: Does User Have An Effect?
Handheld Sensing: Does User Have An Effect?
Newell R. Kitchen, Kenneth A. Sudduth, Scott Newell R. Kitchen, Kenneth A. Sudduth, Scott DrummondDrummond USDA-ARS, Columbia, MOUSDA-ARS, Columbia, MO
Peter Scharf, Harlan Palm, and Kent ShannonPeter Scharf, Harlan Palm, and Kent ShannonUniv. of MO, Columbia, MOUniv. of MO, Columbia, MO