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TRACKS AND TIRES: OHIO CASE STUDY’S
COMPACTIONSMART Program 2017 Waterloo, Ontario
A.A. Klopfenstein
Food, Agricultural and Biological Engineering
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
Introduction (Combine Traverse)
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
Introduction (Applied Downforce)
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
Introduction
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1. Develop an empirical model framework to predict the magnitude of compaction events and the resulting yield penalty;
2. Collect field data to extend the model to estimate yield penalties at higher axles loads, multiple passes, and tracks vs. tires; and
3. Revise model to estimate yield losses for multiple passes, tracks vs. tires, and higher axle loads.
Objectives
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Empirical Model Layout
𝑌𝑐𝑐 = 𝑇𝑑𝑐𝑠𝑡𝑐 0.2𝐷𝑡𝑐𝑇𝑡𝑡(5 − 𝑌𝑎𝑡𝑡) 𝑐1𝐿𝑎 + 𝑐2 + 0.1𝐷𝑠𝑐𝑇𝑠𝑡(10 − 𝑌𝑎𝑠𝑡) 𝑐1𝐿𝑎 + 𝑐2
• Ycf – yield compaction reduction factor (0.0 to 1.0)
• La – axle load (tons)
• Stf – soil type factor (0.0 to 1.0)
• c1 – compaction factor 1
• c2 – compaction factor 2
• Yatt – years after topsoil trafficking event (0 to 5)
• Yast – years after subsoil trafficking event (0 to 10)
• Dtc – topsoil depth compaction factor
• Dsc – subsoil depth compaction factor
• Ttt – topsoil tillage correction factor
• Tst – subsoil tillage correction factor
• Tdf – traction device factor (0.0 to 1.0)
Topsoil Subsoil
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
Empirical Model Layout – Soil Profile Factors
Topsoil Subsoil
𝑌𝑐𝑐 = 𝑇𝑑𝑐𝑠𝑡𝑐 0.2𝐷𝑡𝑐𝑇𝑡𝑡(5 − 𝑌𝑎𝑡𝑡) 𝑐1𝐿𝑎 + 𝑐2 + 0.1𝐷𝑠𝑐𝑇𝑠𝑡(10 − 𝑌𝑎𝑠𝑡) 𝑐1𝐿𝑎 + 𝑐2
• Ycf – yield compaction reduction factor (0.0 to 1.0)
• La – axle load (tons)
• Stf – soil type factor (0.0 to 1.0)
• c1 – compaction factor 1
• c2 – compaction factor 2
• Yatt – years after topsoil trafficking event (0 to 5)
• Yast – years after subsoil trafficking event (0 to 10)
• Dtc – topsoil depth compaction factor
• Dsc – subsoil depth compaction factor
• Ttt – topsoil tillage correction factor
• Tst – subsoil tillage correction factor
• Tdf – traction device factor (0.0 to 1.0)
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
Duiker, 2004
Empirical Model Layout – Soil Profile Factors
Topsoil • 0-12 in • Compaction due to
contact pressure Upper Part of Subsoil
• 12-20 in • Contact pressure and
axle load Lower Subsoil
• 20+ in • Axle load
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
Assumption: moist, arable soil
• 4.4 tons/axle compacts to 12 in
• 6.6 tons/axle compacts to 15.8 in
• 11 tons/axle compacts to 19.7 in
• 16.5 tons/axle compacts to 23.6 in and deeper
Hakaansson, and Reeder, 1994
y = 5.8862x0.5013 R² = 0.9884
0
5
10
15
20
25
30
0 5 10 15 20 25
Dpe
th (I
nche
s)
Axle Load (US Tons)
Axle Load vs Depth of Compaction
Empirical Model Layout – Soil Profile Factors
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
• Ds – depth of soil compaction (cm)
• La – axle load (lbs) • If Ds ≤12
Dsc=1 Ddc=0 • If Ds >12
𝐷𝑡𝑐 = 12𝐷𝑠
𝐷𝑠𝑐 = 𝐷𝑠−12𝐷𝑠
• Dtc=topsoil depth compaction factor
• Dsc= subsoil depth compaction factor
Assumptions • Topsoil 0-12 in • Subsoil 12 in and greater • Yield loss linear relationship
𝐷𝑠 = 5.8862𝐿𝑎0.5013
Empirical Model Layout – Soil Profile Factors
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
Empirical Model Layout – Time Factor
𝑌𝑐𝑐 = 𝑇𝑑𝑐𝑠𝑡𝑐 0.2𝐷𝑡𝑐𝑇𝑡𝑡(5 − 𝑌𝑎𝑡𝑡) 𝑐1𝐿𝑎 + 𝑐2 + 0.1𝐷𝑠𝑐𝑇𝑠𝑡(10 − 𝑌𝑎𝑠𝑡) 𝑐1𝐿𝑎 + 𝑐2
• Ycf – yield compaction reduction factor (0.0 to 1.0)
• La – axle load (tons)
• Stf – soil type factor (0.0 to 1.0)
• c1 – compaction factor 1
• c2 – compaction factor 2
• Yatt – years after topsoil trafficking event (0 to 5)
• Yast – years after subsoil trafficking event (0 to 10)
• Dtc – topsoil depth compaction factor
• Dsc – subsoil depth compaction factor
• Ttt – topsoil tillage correction factor
• Tst – subsoil tillage correction factor
• Tdf – traction device factor (0.0 to 1.0)
Topsoil Subsoil
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
Duiker, 2004
Empirical Model Layout – Time Factor
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Empirical Model Layout – Tillage Factor
𝑌𝑐𝑐 = 𝑇𝑑𝑐𝑠𝑡𝑐 0.2𝐷𝑡𝑐𝑇𝑡𝑡(5 − 𝑌𝑎𝑡𝑡) 𝑐1𝐿𝑎 + 𝑐2 + 0.1𝐷𝑠𝑐𝑇𝑠𝑡(10 − 𝑌𝑎𝑠𝑡) 𝑐1𝐿𝑎 + 𝑐2
• Ycf – yield compaction reduction factor (0.0 to 1.0)
• La – axle load (tons)
• Stf – soil type factor (0.0 to 1.0)
• c1 – compaction factor 1
• c2 – compaction factor 2
• Yatt – years after topsoil trafficking event (0 to 5)
• Yast – years after subsoil trafficking event (0 to 10)
• Dtc – topsoil depth compaction factor
• Dsc – subsoil depth compaction factor
• Ttt – topsoil tillage correction factor
• Tst – subsoil tillage correction factor
• Tdf – traction device factor (0.0 to 1.0)
Topsoil Subsoil
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Empirical Model Layout – Tillage Factor
• Td – tillage depth (in)
• Ds – depth of soil compaction (in) • If Td ≤12
𝑇𝑡𝑡 = 𝑇𝑑𝐷𝑠
𝑇𝑠𝑡 = 1
• If Td >12
𝑇𝑡𝑡 = 0 𝑇𝑠𝑡 = 𝑇𝑑−12𝐷𝑠−12
• Ttt – topsoil tillage correction factor
• Tst – subsoil tillage correction factor
Assumptions • Topsoil 0-12 in • Subsoil 12 in and greater • Tillage correction factor linear
relationship
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Empirical Model Layout – Undercarriage Factor
𝑌𝑐𝑐 = 𝑇𝑑𝑐𝑠𝑡𝑐 0.2𝐷𝑡𝑐𝑇𝑡𝑡(5 − 𝑌𝑎𝑡𝑡) 𝑐1𝐿𝑎 + 𝑐2 + 0.1𝐷𝑠𝑐𝑇𝑠𝑡(10 − 𝑌𝑎𝑠𝑡) 𝑐1𝐿𝑎 + 𝑐2
• Ycf – yield compaction reduction factor (0.0 to 1.0)
• La – axle load (tons)
• Stf – soil type factor (0.0 to 1.0)
• c1 – compaction factor 1
• c2 – compaction factor 2
• Yatt – years after topsoil trafficking event (0 to 5)
• Yast – years after subsoil trafficking event (0 to 10)
• Dtc – topsoil depth compaction factor
• Dsc – subsoil depth compaction factor
• Ttt – topsoil tillage correction factor
• Tst – subsoil tillage correction factor
• Tdf – traction device factor (0.0 to 1.0)
Topsoil Subsoil
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
Empirical Model Layout – Compaction and Moisture Factors
𝑌𝑐𝑐 = 𝑇𝑑𝑐𝑠𝑡𝑐 0.2𝐷𝑡𝑐𝑇𝑡𝑡(5 − 𝑌𝑎𝑡𝑡) 𝑐1𝐿𝑎 + 𝑐2 + 0.1𝐷𝑠𝑐𝑇𝑠𝑡(10 − 𝑌𝑎𝑠𝑡) 𝑐1𝐿𝑎 + 𝑐2
• Ycf – yield compaction reduction factor (0.0 to 1.0)
• La – axle load (tons)
• Stf – soil type factor (0.0 to 1.0)
• c1 – compaction factor 1
• c2 – compaction factor 2
• Yatt – years after topsoil trafficking event (0 to 5)
• Yast – years after subsoil trafficking event (0 to 10)
• Dtc – topsoil depth compaction factor
• Dsc – subsoil depth compaction factor
• Ttt – topsoil tillage correction factor
• Tst – subsoil tillage correction factor
• Tdf – traction device factor (0.0 to 1.0)
Topsoil Subsoil
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Soil: Hoytville silty clay loam • Poorly drained lake-
bed soil Corn/soybean rotation Plots compacted autumn
• 20 t/axle; 10 t/axle; and control (none)
No-till trials
Materials and Methods
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
y = 0.0111x - 0.0113
y = 0.0046x - 0.1136
y = 0.0078x - 0.0624
-20%
-10%
0%
10%
20%
30%
40%
50%
0 5 10 15 20 25 30 35 40
Yiel
d Lo
ss (%
)
Axle Load (US Short Ton)
Axle Load vs Yield Loss Corn 2003-2010
WET
DRY
NORMAL
NO YIELD LOSS IN GRAY AREA!
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
Empirical Model Layout
𝑌𝑐𝑐 = 𝑇𝑑𝑐𝑠𝑡𝑐 0.2𝐷𝑡𝑐𝑇𝑡𝑡(5 − 𝑌𝑎𝑡𝑡) 𝑐1𝐿𝑎 + 𝑐2 + 0.1𝐷𝑠𝑐𝑇𝑠𝑡(10 − 𝑌𝑎𝑠𝑡) 𝑐1𝐿𝑎 + 𝑐2
• Ycf – yield compaction reduction factor (0.0 to 1.0)
• La – axle load (tons)
• Stf – soil type factor (0.0 to 1.0)
• c1 – compaction factor 1
• c2 – compaction factor 2
• Yatt – years after topsoil trafficking event (0 to 5)
• Yast – years after subsoil trafficking event (0 to 10)
• Dtc – topsoil depth compaction factor
• Dsc – subsoil depth compaction factor
• Ttt – topsoil tillage correction factor
• Tst – subsoil tillage correction factor
• Tdf – traction device factor (0.0 to 1.0)
Topsoil Subsoil
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Results and Discussion
• 36 rows, 22-inch spacing, center fill (3 locations) • 48 rows, 20-inch spacing, row-unit boxes (4 locations) • 36 rows, 20-inch spacing, center fill (5 locations) • Assume: Normal and wet soil moisture, year 0, soil factor of 1, axle load 22,000 lbs
Ahlers, 2012
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0
50
100
150
200
250
1 2 3 4 5 6 7 8 9 10 11 12
Cor
n Yi
eld
(bu/
acre
)
Location
Pioneer Yield Loss vs Projected Yield Loss Normal Wet Center Section
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
67,000 kg~74 t on 3 axles = 22,000 kg~24 t/axle
Food, Agricultural and Biological Engineering
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Corn Mass – 69,000 lbs Total Grain Cart Mass – 98,100 lbs
Corn Mass – 61,100 lbs Total Grain Cart Mass– 73,400 lbs
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
67,000 kg~74 t on 3 axles = 22,000 kg~24 t/axle
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
67,000 kg~74 t on 3 axles = 22,000 kg~24 t/axle
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2014 Corn Results
Corn Yield (bu/ac)
Machine
Predicted Yield Compaction Model
Average Yield (6 row pass)
Trafficked Yield (bu/ac)
Yield Loss (%)
Trafficked Yield (bu/ac)
Yield Loss (%)
Std. Dev.
Wheeled 183.32 11.95 185.5a 10.90 16.3 Killbros 1950 Tracked - - 202.2b 2.88 38.1 Brent 1594
Control Yield (bu/ac) 208.2b - 14.3
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
2014 Soybean Results
Soybean Yield (bu/ac)
Machine
Predicted Yield Compaction Model Plot Yields and Stats
Trafficked Yield (bu/ac)
Yield Loss (%)
Trafficked Yield (bu/ac)
Yield Loss (%)
Std. Dev.
Wheeled 33.57 14.36 28.1a 28.32 20.4 Killbros 1950 Tracked - - 36.3b 7.40 17.5 Brent 1594
Control Yield (bu/ac) 39.2b - 9.1
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
2014 Summary • Corn Results
• Wheeled vs Control • 95% confidence level
• Tracked vs Control • Not able to show statistically significant results
• Wheeled vs Tracked • 80% confidence level
• Soybean Results • Wheeled vs Control
• 95% confidence level
• Tracked vs Control • Not able to show statistically significant results
• Wheeled vs Tracked • 75% confidence level
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2015 Compaction Plot
• Beck’s Hybrids PFR Facility • London, Ohio • 41 acres • Spring tillage operation for soil
profile reset • AB lines for passes 45 ft
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Traffic Event Treatments
• Grain Cart Configurations • Wheels – 96,000 lbs • Tracks – 103,100 lbs • Equalizer Tracks – 104,800
lbs • Number of Passes (Single,
Double and Triple) • 5 replications
• 3 hybrids • 4 replications
• Randomized block design • 540 total plots
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Loaded Grain Cart Weight (1,300 bu)
Wheeled - 96,000 lbs Equalizer - 104,800 lbs, Regular - 103,100 lbs
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As-applied Downforce Map
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Airscout Imagery
10-11-15 5-19-15 8-14-15
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Airscout – 05-20-2015 RGB Image
2015 Compaction Plots
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eBee – 06-24-2015 RGB/Thermal Image
eBee – 07-01-2015 RGB/Thermal Image
2015 Compaction Plots
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eBee UAV Imagery - NDVI
7-1-15
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Tracking Passes
Equalizer Tracks Regular Tracks
Wheels
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Soil Measurements • 90 soil zone locations selected
based off RGB image by soil color • Light • Medium • Dark
• Spectrum’s SC 900 penetrometer (to a depth of 18 in.)
• TDR 300 soil moisture sensor (at depths of 0-3 in. and 0-8 in.)
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
Soil Moisture
• Two soil moisture depths: • 3.0 inches • 8.0 inches
• Zone moisture was taken 2 times
• In the middle (control) • In the track (compaction
zone) • Averaged together for a single
reading in each location • Volumetric water content (VWC)
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
Soil Moisture (0-8 in. depth)
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Soil Moisture (0-3 in. depth)
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Soil Cone Penetrometer
• Five readings were taken in the compaction zone and five outside the compaction zone at each location
• A coin was flipped to use either the north or south compacted area from the grain cart
• Data were averaged for each location • Data were summarized for the
following depths: • 0, 5, 10, & 15 in. • 0-6 in. • 7-12 in. • 13-18 in.
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
Soil Cone Penetrometer Results (0-6 in.)
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Soil Cone Penetrometer Results (7-12 in)
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Soil Cone Penetrometer Results (13-18 in.)
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Harvesting
• Harvested 8 rows to allow for hand measurements of different pass types and soil zones
• Harvested rest of compaction plots in a 2-4-2 harvest pattern to increase yield map resolution and ease of data analysis for compaction zones
• For each pass field weights were collected to support post-harvest yield map correction.
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
Yield Data Statistics
Statistical Summary for Yield
Equalizer Tracks Regular Tracks Wheels
Compacted Control Compacted Control Compacted Control Min 55.1 86.7 19.9 58.1 27.5 56.7 Max 184.0 205.1 192.9 217.2 194.0 213.3 SD 34.7 27.0 39.6 36.1 36.0 31.1
Mean 127.0ab 157.0a 123.0c 153.0c 114.0bd 149.0d
• Data were summarized for the following:
• 1, 2, & 3 passes • Hybrid • Undercarriage
• Statistics on following configurations:
• Equalizer vs regular • Equalizer vs wheels • Regular vs wheels • Each undercarriage vs hybrid • Each undercarriage and
number of passes vs hybrid
Hybrid Passes Test Description Equalizer Tracks Regular Tracks Wheels
Compacted Control Compacted Control Compacted Control All All Compacted zone vs control 127 157 123 153 114 149 All 1 Compacted zone vs control 129 165 130 158 117 152 All 2 Compacted zone vs control 128 152 126 152 116 150 All 3 Compacted zone vs control 125 156 108 145 111 146
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Yield Results (Number of Passes)
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Yield Results (Tires vs. Tracks)
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-15%
-10%
-5%
0%
5%
10%
15%
20%
25%
30%
35%
40%
0 5 10 15 20 25 30 35 40 45 50
Yie
ld L
oss (
%)
Axles Load (US Short Ton)
WET
NORMAL
DRY
NO YIELD LOSS IN GRAY AREA!
Table of New Compaction Correction Factors
Soil Moisture Factor 1 Factor 2
Old New Old New Wet 0.0110725 0.0067504 -0.0112554 -0.0047539
Normal 0.0078363 0.0056458 -0.0624250 -0.0312272 Dry 0.0046000 0.0045411 -0.1135946 0.0067504
Model Correction Factors
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Model Predictions
Modeled Compaction Yield Reduction Without Track Correction Factor (%)
Soil Moisture Equalizer Tracks Regular Tracks Wheels
Wet 28.1% 27.7% 21.2%
Normal 21.3% 21.0% 15.0%
Dry 19.7% 19.4% 13.5%
Yield Reduction for Field Results
Equalizer Tracks Regular Tracks Wheels 19.1% 19.6% 23.5%
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
2016 Compaction Plot
• Beck’s Hybrids PFR Facility • London, Ohio • 40 acres • Spring tillage operation for soil
profile reset • AB lines for passes 45 ft
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
Traffic Event Treatments
• Grain Cart Configurations • Wheels 1 – 96,000 lbs
• Flotation 1250/45R32 • Wheels 2 – 96,000 lbs
• IF 1250/50R32 • Equalizer Tracks – 104,800 lbs
• 42 inch belt • Full and Half Load • Number of Passes (Single and
Triple) • 2 hybrids • Randomized block design • 96 total plots
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
2016 Soybean Compaction Plots – Manned Flight (0.5 m)
Visible 7-12-16 ADVI 7-12-16
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
2016 Soybean Compaction Plots – UAV eBee Flight with Sequoia (4 in)
Visible 7-21-16 NDVI 7-21-16 Visible 9-7-16 NDVI 9-7-16
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2016 Soybean Compaction Plots (Initial Results)
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Conclusions
Develop an empirical model framework to predict the magnitude of compaction events and the resulting yield penalty. 1. A relatively simple and robust empirical model was developed for predicting
yield reduction for corn (Note: Original model did a good job of predicting yield losses for grain carts up to 20 T within 2.0% of 2014 study.).
Collect field data to extend the model to estimate yield penalties at higher axles loads, multiple passes, and tracks vs. tires. 2. Data were collected for grain cart loads of 48 T, tracks vs. wheels, and multiple
passes. Grain carts caused up to a 23.5% yield reduction across all hybrids and configurations evaluated.
Revise model to estimate yield losses for multiple passes, tracks vs. tires, and higher axle loads. 3. Number of passes vs. mean yield reduction were not significant for the grain
cart configurations evaluated. 4. Yield reduction for Equalizer Tracks averaged 19.1 % across all treatments
compared to 19.6% for the regular tracks. 5. Yield reductions for Equalizer Tracks vs. Wheels were significant so a
correction factor of 0.8065 was added to the model.
FOOD, AGRICULTURAL AND BIOLOGICAL ENGINEERING
1. Modify compaction prediction model to include multiple crops (i.e., soybeans, wheat, and canola);
2. Conduct field research and verification for soil type correction factors;
3. Conduct field research to determine and verify tillage correction factor, pass multiplier, multiple axles, and soil moisture content to yield loss model;
4. Conduct field research for the creation of tire construction correction factors (i.e., bias ply, radial and IF); and
5. Merge remote sensed imagery, machine data and model results for refinement of yield maps resolution.
Future Work