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Advancing from a‘Person Who Grows Corn’
to a ‘Corn Grower’
Dave Franzen, PhDProfessor Soil Science
Extension Soil Specialist, NDSU
Growing corn‐
How hard could it be?
Throw some fertilizer onthrow some corn seed in the groundspray some glyphosate on itgo fishingharvest itsell it
Simple
If this is what you do, you are‐
A Person Who Grows Corn!
A corn grower does the following –
‐ Discriminating seed corn purchaser‐ Recognizes the corn planter as theirmost important piece of production equipment
‐ Applies herbicide pre and/or post in a very timely manner
‐ Applies adequate N, P, with attention to K, S and Zn
‐ Uses appropriate site‐specific nutrientmanagement tools and techniques
‐ Harvests to minimize compaction‐ Harvest logistics are appropriate for volume
Seed corn selection‐
‐ Maturity ‐needs to fit the growing degreeof the region Too early misses yieldToo late misses maturity‐ increasesdrying costs
What traits are necessary?
Is corn borer an issue?
Is corn rootworm an issue?
Herbicide selection?
Drought characteristics?Nitrogen efficiency?
Seed Spacing‐
Nafziger (Illinois) reported that‐
A 2.5 bushel per acre loss from each 1‐inchincrease in standard deviation of seedspacing.
Another study reported a 3.4 bushel per acreimprovement in yield with each 1‐inchdecrease in standard deviation of seed spacing.
Nafziger, 2002
Seed spacing in 30 inch rows?
36,000 plants per acre?
Length of 30 inch row per acre = 43,560 / 2.5 = 17,424
36,000 plants per acre / 17,424 feet row per acre =5.8 inches between seeds
Planter boxes should be calibrated. Don’t trustnew boxes to be correctly calibrated.
Fast planter speeds increase seed spacingvariability and decrease yield.
Timing of glyphosate application in corn
Pre yield EONRPreemerge control 222 bu/a 1004 inch weeds 12012 inch weeds 164None >200
Boerboom and Laboski‐ 2006
Current published N recommendation for corn‐
N Rate (pounds N per acre) =Yield Potential (bushels per acre) X 1.2
less soil test nitrate‐N to 2 foot depthless previous crop credit
Why I dislike the current N recommendationsfor corn‐
Yield Po
tential
N Rate
200
240
Began to accumulate modern corn N ratedata in 2010.
Sites‐ 2010‐ 16 eastern, 2 western‐ 2011‐ 14 eastern‐ western sites lost‐2012‐ 22 eastern – 4 western‐ 2013‐ 15 eastern‐ 4 western
Also‐ 9 sites from southern Manitoba‐ 21 sites from NW Minnesota‐ still accumulating sites from Northern SD
Total of over 100 sites within the past 12 years.
y = ‐0.001x2 + 0.3676x + 129.81R² = 0.0952
0
50
100
150
200
250
300
0 50 100 150 200 250
Corn Yield, b
ushe
ls per acre
N Rate Only, pounds N per acre
North Dakota, NW Minnesota and Southern Manitoba Corn N Rate Trials 2001‐2013N Rate Only vs Yield‐ ALL SITES
y = ‐0.0008x2 + 0.5026x + 89.834R² = 0.1857
0
50
100
150
200
250
300
0 50 100 150 200 250 300 350 400 450
Corn Yield, b
ushe
ls per acre
Total Known Available N, pounds N per acre
North Dakota, NW Minnesota and Southern Manitoba N Rate Trials, Total Known Available N vs Corn Yield,
All Sites 2001‐2013
y = ‐0.0007x2 + 0.4961x + 76.076R² = 0.4993
0
50
100
150
200
250
0 50 100 150 200 250 300 350 400 450
Yield, bushe
ls per acre
Total Known Available N, pounds per acre
Yield vs Total Known Available N, Long‐term No‐till Sites 2010‐2013
y = ‐0.0009x2 + 0.5301x + 91.271R² = 0.1226
0
50
100
150
200
250
300
0 50 100 150 200 250 300 350 400 450
Corn Yield, b
ushe
ls per acre
Total Known Available N, pounds N per acre
Total Available N vs Corn Yield, High Clay Soils, North Dakota, NW Minnesota and Southern Manitoba,
2001‐2013
y = ‐0.0009x2 + 0.5354x + 114.01R² = 0.2199
0
50
100
150
200
250
300
0 50 100 150 200 250 300 350 400
Corn Yield, b
ushe
ls per acre
Total Known Available N, pounds N per acre
High Clay Sites that Exceeded 160 bushels per acre, North Dakota, NW Minnesota and Southern Manitoba,
2001‐2013
y = ‐0.0005x2 + 0.3666x + 64.644R² = 0.2991
0
20
40
60
80
100
120
140
160
180
0 50 100 150 200 250 300 350 400 450
Corn Yield, b
ushe
ls per acre
Total Known Available N, pounds per acre
High Clay Sites Yielding Under 160 bushels per acre, North Dakota, NW Minnesota, and Southern Manitoba,
2001‐2013
y = ‐0.0008x2 + 0.5023x + 100.76R² = 0.2478
0
50
100
150
200
250
300
0 50 100 150 200 250 300 350 400 450
Corn Yield, b
ushe
ls per acre
Total Known Available N, pounds N per acre
North Dakota, NW Minnesota, and Southern Manitoba Medium Textured Conventional Tillage Sites Total Known
Available N vs Corn Yield
y = ‐0.0009x2 + 0.5029x + 114.43R² = 0.267
0
50
100
150
200
250
300
0 50 100 150 200 250 300 350 400 450
Corn Yield, b
ushe
ls per acre
Total Known Available N, pounds N per bushel
Eastern Medium Texture Sites Yielding Greater than 160 bushels per acre Corn, North Dakota, NW Minnesota,
Southern Manitoba, 2001‐2013
y = ‐0.0002x2 + 0.2498x + 83.064R² = 0.3468
0
20
40
60
80
100
120
140
160
180
0 50 100 150 200 250 300 350 400
Corn Yield, b
ushe
ls per acre
Total Known Available N, pounds N per acre
Medium Textured Sites, North Dakota, NW Minnesota and Southern Manitoba with High Yields Less than 160
Bushels Per Acre
The “Return to N” model-
Developed by John Sawyer, Iowa Stateand Emerson Nafziger, Illinois(2005, Proc. Ext-Ind Soil Fert. Conf.)
This model is used in several corn-beltstates, including Iowa, Illinois, Wisconsin, Minnesota,Ohio, and Michigan
0
200
400
600
800
1000
1200
1400
0 50 100 150 200 250 300 350 400
20N3C
30N3C
40N3C
50N3C
60N3C
70N3C
80N3C
90N3C
100N3C
20N4C
30N4C
40N4C
40N4C
50N4C
60N4C
70N4C
80N4C
90N4C
100N4C
20N5C
30N5C
40N5C
50N5C
60N5C
70N5C
80N5C
90N5C
Medium TextureSites- AllReturn to N$3-$8 corn20 cent to $ N
200
300
400
500
600
700
800
900
1000
0 100 200 300 400
20N3C
30N3C
40N3C
50N3C
60N3C
70N3C
80N3C
90N3C
100N3C
20N4C
30N4C
40N4C
40N4C
50N4C
60N4C
70N4C
80N4C
90N4C
100N4C
20N5C
30N5C
40N5C
50N5C
60N5C
70N5C
80N5C
90N5C
High Clay YieldsGreater than 160 bushels per acreMERN $4 corn,40 cent N= 260 lb N per acre
0
100
200
300
400
500
600
700
0 100 200 300 400
20N3C
30N3C
40N3C
50N3C
60N3C
70N3C
80N3C
90N3C
100N3C
20N4C
30N4C
40N4C
40N4C
50N4C
60N4C
70N4C
80N4C
90N4C
100N4C
20N5C
30N5C
40N5C
50N5C
60N5C
70N5C
80N5C
90N5C
High Clay with YieldsLess than 160 bushelsper Acre.MERN $4 cornand 40 cent N~ 260
100
200
300
400
500
600
700
800
900
0 100 200 300 400
Return to
N, $
per acre
Total Known Available N, pounds per acre
20N3C
30N3C
40N3C
50N3C
60N3C
70N3C
80N3C
90N3C
100N3C
20N4C
30N4C
40N4C
40N4C
50N4C
60N4C
70N4C
80N4C
90N4C
100N4C
20N5C
30N5C
40N5C
50N5C
60N5C
70N5C
80N5C
90N5C
100N5C
Medium TextureEastern Sites w/NW MN and S MBYields Greater than160 Bushels per AcreMERN $4 corn and40 cent N~ 240 pounds N peracre
High clay soils and at-risk mediumtexture soils have a special need for in-season (side-dress) N application.
Rate is probably not the answer forthese soils- The answer is likely timing.
How do we figure rate at side-dress?
Cumulative N uptake for corn‐ from Iowa State Ext. Spec. Rpt 48, 1986
Economics of preplant N vs split-applied N
On high-clay soils, it took about 2 Xthe N rate to achieve similar (?) yields asmedium textured soils with better drainage
120 lb N X $0.40/lb N = $ 48/acre.
Cost in yield and return if you ignore a wet spring-50 bu/acre @ $4/bu = $200/acre.
Cost of a 12-row coulter unit for 28% side-dress = $50,000.
Cost of 2nd application $8/acre.
Extra cost of 80 lb N as 28% vs urea- $4
Total cost per acre of side-dress over 1,500acres corn- paying for coulter unit in year 1-$68,000
1,500 acres X 120 lb N X $0.40 = $72,0001,500 acres X $200 lost revenue = $300,000Total cost of not side-dressing = $372,000
Return for side-dressing =
$372,000 - $68,000 = $304,000
Active optical sensors have been identifiedas a tool to increase nitrogen‐use efficiency
Greenseeker (Trimble)
Holland Crop Circle Sensor (Holland Scientific)
Active optical sensors shine their ownlight onto foliage-
Red/Near Infrared ratio (NDVI)is related to two-dimensional foliageground cover.
Red Edge/Near Infrared ration (RE-NDVI)is related to tints of relative greenness
Algorithms will not use sensorreadings by themselves.
We will use a normalization conceptdeveloped by Oklahoma State Univ.during their development of the GreenSeeker
INSEY-In Season Estimate of Yield
INSEY-
Sensor reading / growing degree daysfrom planting date
y = 84.013e650.61xR² = 0.2666
0
50
100
150
200
250
300
0 0.0005 0.001 0.0015 0.002
Corn Yield, b
u/acre
Greenseeker 5‐6 Leaf INSEY
2011‐2012 All Eastern Conventional Till Sites Greenseeker 5‐6 Leaf INSEY vs Corn Yield
y = 66.433e890.67xR² = 0.2316
0
50
100
150
200
250
300
0 0.0002 0.0004 0.0006 0.0008 0.001 0.0012 0.0014
Corn Yield, bu/acre
Greenseeker INSEY
2011‐2012 All Eastern Conventional Till Sites Greenseeker 10‐12 Leaf INSEY vs Corn Yield
Use zone sampling to direct the initial N‐rate to field
Example field- 160 acres
Apply about 200 lbN to a small referencearea
When applicator enters the field to apply side‐dress application, thereference area serves as the INSEYthat is the maximum supported byan application, less an INSEY of 5%.
Example field- 160 acres
Reference areapreviously highlyfertilized with N
INSEY
Yiel
d
ReferenceINSEY
Reference Yield
INSEY
Yiel
d
ReferenceINSEY
Reference Yield
INSEY in field
Field Yield estimate
INSEY
Yiel
d
ReferenceINSEY
Reference Yield
INSEY in field
Field Yield estimate
INSEY
Yiel
d
ReferenceINSEY
Reference Yield
INSEY in field
Field Yield estimate
Corn yield difference in pounds peracre.X 1.25 % N in corn graindivided by efficiency factor 0.6= N rate
Example-
Reference yield predicted- 220 bushels
In-field yield estimated- 160 bushels
difference = 60 bushels X 56 lb N/bushel= 3360 poundsX 0.0125 = 42 lb N42 /0.6 efficiency factor = 70 lb Nat that location.
SAMPLINGGRID SAMPLING
Grid sampling uses sufficientlydense sampling to reveal fertilitypatterns.
SAMPLINGZone sampling
Zone sampling assumes that fertilitypatterns exist because of some logical,predicable reason.
Patterns of mobile nutrientstend to be stable between years.
0 40 80 120Nitrate-N lb/A 2 ft.
20 50 80 110
Nitrate-N lb/A 2 ft.
N
1994 1995
Relativeelevation, ft.
20 50 80 110 140
Nitrate-N lb/A 2 ft.
0 -16
-32
Valley City N over topography
Mobile Nutrients Move, But They Tend To Move To The Same Places.
Electrical conductivity
Electrical conductivity, EM-38
Remote imagery
Yield
Corn is a sensitive crop to P. Enjoysmedium or higher soil test P.
2 X 2 was designed for corn
P Placement Corn Yield, bu/a
None 102Starter* 153Deep Band 146Broadcast 166
*Starter and Deep Band, 50 lb P2O5- Brcst 100 lb P2O5
P Placement on initially low testing (3 ppm) soilMinnesota- from Randall, 2006
Corn yield with in-furrow 10-34-0, Carrington, 2007.
Rate Yield
Gal/ac Bu/ac
0 1012 121
4 125
6 150
8 156
10 153
*Conventional tillage*Soil : 124 lb N/acre prior to planting;
5 ppm (L) P (Olsen)
P. Hendrickson
No difference in plant stand among fertilizer rates
From Gelderman, 2009
150
200
250
300
350
400
K, ppm
Valley City, ND soil test K draped over topography
Site/texture S applied, lb/acre0 6
Yield, bu/acreloamy fine sand 166 174*
silty clay loam 184 184loamy fine sand 99 108*Loam 150 161*sandy loam 140 154*silt loam 149 160*
Response of corn at six locations in Minnesota to sulfur (Rehm, 2005).* Response is significant at P > 0.05
Before 2005, S deficiency in Iowa was virtually unknown. A series of experiments in 2005‐2006 showed a consistent response to S in some soils.
In 2007 17 of 20 sites showed a significant response to SIn 2008, 11 of 25 sites showed a significant response to SAverage response to S was 13 bu/acre
When grouped by texture within responsive sites, heavier soil increase was 15 bu/acre
Sandier soil increase was 28 bu/acre
(Sawyer, 2009)
Site/Texture Yield w/o S Yield w/S
1 / loamy fine sand 123 151
2 / loamy fine sand 154 198
3 / loamy fine sand 88 108
4 / loam 196 204 (NS)
5 / silt loam 118 171
6 / silt loam 129 167
Across all sites 129 167
Iowa S rescue on corn. 40 lb S/acre as gypsum broadcast side‐dress early season after on‐set of deficiency symptoms. Sawyer, 2009.
ANY crop is susceptible to S deficiency if soiland water conditions are favorable‐
Most at risk‐Sandy soils
Low organic matterSignificant rainfall in fall or springHigher landscape positions
Least at riskClay soils
High organic matterDry conditions in fall/springDepressions
Zinc deficiency
99.9% water soluble ZnSO4 on left/ 7& water soluble ZnOS04 on rightFrom Amrani et al., 1997. CSU
Rate of Zn,lb/acre Yield, bu/a
0 820.1 1190.3 1271.0 1353.0 132
9% EDTA is 1 lb Zn per gallon.
Zinc in a low-testing soil in Nebraska (from Rehmand Schmitt, 1997.
Grain harvest logistics‐
Combine‐
Grain cart‐
Trucking‐
On‐farm drying and storage
If you address all of these
issues, you will be a
Corn Grower !