1 Advancing from a Person Who Grows Corn to a Corn Grower Dave Franzen, PhD Professor Soil Science Extension Soil Specialist, NDSU
2 Growing corn How hard could it be?
3 Throw some fertilizer on throw some corn seed in the ground spray some glyphosate on it go fishing harvest it sell it Simple If this is what you do, you are
4 A Person Who Grows Corn!
5 A corn grower does the following Discriminating seed corn purchaser Recognizes the corn planter as their most 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 nutrient management tools and techniques Harvests to minimize compaction Harvest logistics are appropriate for volume
6 Seed corn selection Maturity needs to fit the growing degree of the region Too early misses yield Too late misses maturity increases drying costs
7 What traits are necessary? Is corn borer an issue? Is corn rootworm an issue? Herbicide selection? Drought characteristics? Nitrogen efficiency?
8 Seed Spacing Nafziger (Illinois) reported that A 2.5 bushel per acre loss from each 1 inch increase in standard deviation of seed spacing. Another study reported a 3.4 bushel per acre improvement in yield with each 1 inch decrease in standard deviation of seed spacing.
10 Nafziger, 2002
11 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 trust new boxes to be correctly calibrated.
12 Fast planter speeds increase seed spacing variability and decrease yield.
13 Timing of glyphosate application in corn Pre yield EONR Preemerge control 222 bu/a inch weeds inch weeds 164 None >200 Boerboom and Laboski 2006
14 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 depth less previous crop credit
15 Why I dislike the current N recommendations for corn Yield Potential N Rate
16 Began to accumulate modern corn N rate data in Sites eastern, 2 western eastern western sites lost eastern 4 western 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.
17 300 North Dakota, NW Minnesota and Southern Manitoba Corn N Rate Trials N Rate Only vs Yield ALL SITES Corn Yield, bushels per acre y = 0.001x x R² = N Rate Only, pounds N per acre
18 300 North Dakota, NW Minnesota and Southern Manitoba N Rate Trials, Total Known Available N vs Corn Yield, All Sites Corn Yield, bushels per acre y = x x R² = Total Known Available N, pounds N per acre
19 Yield vs Total Known Available N, Long term No till Sites y = x x R² = Yield, bushels per acre Total Known Available N, pounds per acre
20 300 Total Available N vs Corn Yield, High Clay Soils, North Dakota, NW Minnesota and Southern Manitoba, Corn Yield, bushels per acre y = x x R² = Total Known Available N, pounds N per acre
21 300 High Clay Sites that Exceeded 160 bushels per acre, North Dakota, NW Minnesota and Southern Manitoba, Corn Yield, bushels per acre y = x x R² = Total Known Available N, pounds N per acre
22 180 High Clay Sites Yielding Under 160 bushels per acre, North Dakota, NW Minnesota, and Southern Manitoba, Corn Yield, bushels per acre y = x x R² = Total Known Available N, pounds per acre
23 300 North Dakota, NW Minnesota, and Southern Manitoba Medium Textured Conventional Tillage Sites Total Known Available N vs Corn Yield Corn Yield, bushels per acre y = x x R² = Total Known Available N, pounds N per acre
24 300 Eastern Medium Texture Sites Yielding Greater than 160 bushels per acre Corn, North Dakota, NW Minnesota, Southern Manitoba, Corn Yield, bushels per acre y = x x R² = Total Known Available N, pounds N per bushel
25 180 Medium Textured Sites, North Dakota, NW Minnesota and Southern Manitoba with High Yields Less than 160 Bushels Per Acre Corn Yield, bushels per acre y = x x R² = Total Known Available N, pounds N per acre
26 The Return to N model- Developed by John Sawyer, Iowa State and Emerson Nafziger, Illinois (2005, Proc. Ext-Ind Soil Fert. Conf.) This model is used in several corn-belt states, including Iowa, Illinois, Wisconsin, Minnesota, Ohio, and Michigan
27 1400 Medium Texture Sites- All Return to N $3-$8 corn 20 cent to $ N N3C 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
28 High Clay Yields Greater than 160 bushels per acre MERN $4 corn, 40 cent N = 260 lb N per acre N3C 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
29 High Clay with Yields Less than 160 bushels per Acre. MERN $4 corn and 40 cent N ~ N3C 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
30 900 Medium Texture Eastern Sites w/ NW MN and S MB Yields Greater than 160 Bushels per Acre MERN $4 corn and 40 cent N ~ 240 pounds N per acre Return to N, $ per acre N3C 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 Total Known Available N, pounds per acre 100N5C
31 High clay soils and at-risk medium texture soils have a special need for in-season (side-dress) N application. Rate is probably not the answer for these soils- The answer is likely timing. How do we figure rate at side-dress?
32 Cumulative N uptake for corn from Iowa State Ext. Spec. Rpt 48, 1986
33 Economics of preplant N vs split-applied N On high-clay soils, it took about 2 X the N rate to achieve similar (?) yields as medium 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 $4/bu = $200/acre.
34 Cost of a 12-row coulter unit for 28% sidedress = $50,000. Cost of 2 nd application $8/acre. Extra cost of 80 lb N as 28% vs urea- $4 Total cost per acre of side-dress over 1,500 acres corn- paying for coulter unit in year 1- $68,000
35 1,500 acres X 120 lb N X $0.40 = $72,000 1,500 acres X $200 lost revenue = $300,000 Total cost of not side-dressing = $372,000 Return for side-dressing = $372,000 - $68,000 = $304,000
36 Active optical sensors have been identified as a tool to increase nitrogen use efficiency Greenseeker (Trimble) Holland Crop Circle Sensor (Holland Scientific)
37 Active optical sensors shine their own light onto foliage- Red/Near Infrared ratio (NDVI) is related to two-dimensional foliage ground cover. Red Edge/Near Infrared ration (RE-NDVI) is related to tints of relative greenness
38 Algorithms will not use sensor readings by themselves. We will use a normalization concept developed by Oklahoma State Univ. during their development of the GreenSeeker INSEY- In Season Estimate of Yield
39 INSEY- Sensor reading / growing degree days from planting date
40 All Eastern Conventional Till Sites Greenseeker 5 6 Leaf INSEY vs Corn Yield Corn Yield, bu/acre y = e x R² = Greenseeker 5 6 Leaf INSEY All Eastern Conventional Till Sites Greenseeker Leaf INSEY vs Corn Yield Corn Yield, bu/acre y = e x R² = Greenseeker INSEY
41 Example field- 160 acres Use zone sampling to direct the initial N rate to field Apply about 200 lb N to a small reference area
42 Example field- 160 acres When applicator enters the field to apply side dress application, the reference area serves as the INSEY that is the maximum supported by an application, less an INSEY of 5%. Reference area previously highly fertilized with N
43 Yield Reference Yield Reference INSEY INSEY
44 Yield Reference Yield Field Yield estimate INSEY in field Reference INSEY INSEY
45 Yield Reference Yield Field Yield estimate INSEY in field Reference INSEY INSEY
46 Corn yield difference in pounds per acre. X 1.25 % N in corn grain divided by efficiency factor 0.6 = N rate Yield Reference Yield Field Yield estimate INSEY in field Reference INSEY INSEY
47 Example- Reference yield predicted- 220 bushels In-field yield estimated- 160 bushels difference = 60 bushels X 56 lb N/bushel = 3360 pounds X = 42 lb N 42 /0.6 efficiency factor = 70 lb N at that location.
48 SAMPLING GRID SAMPLING Grid sampling uses sufficiently dense sampling to reveal fertility patterns.
49 SAMPLING Zone sampling Zone sampling assumes that fertility patterns exist because of some logical, predicable reason.
50 Patterns of mobile nutrients tend to be stable between years N Nitrate-N lb/a 2 ft Nitrate-N lb/a 2 ft.
51 Valley City N over topography Relative elevation, ft Nitrate-N lb/a 2 ft.
52 Mobile Nutrients Move, But They Tend To Move To The Same Places.
53 Electrical conductivity
54 Electrical conductivity, EM-38
55 Remote imagery
57 Corn is a sensitive crop to P. Enjoys medium or higher soil test P.
58 2 X 2 was designed for corn
59 P Placement Corn Yield, bu/a None 102 Starter* 153 Deep Band 146 Broadcast 166 *Starter and Deep Band, 50 lb P 2 O 5 - Brcst 100 lb P 2 O 5 P Placement on initially low testing (3 ppm) soil Minnesota- from Randall, 2006
60 Corn yield with in-furrow , *Conventional tillage *Soil : 124 lb N/acre prior to planting; 5 ppm (L) P (Olsen) Carrington, Rate Gal/ac Yield Bu/ac No difference in plant stand among fertilizer rates P. Hendrickson
63 From Gelderman, 2009
65 Valley City, ND soil test K draped over topography K, ppm
66 Response of corn at six locations in Minnesota to sulfur (Rehm, 2005). * Response is significant at P > 0.05 Site/texture S applied, lb/acre 0 6 Yield, bu/acre loamy fine sand * silty clay loam loamy fine sand * Loam * sandy loam * silt loam *
67 Before 2005, S deficiency in Iowa was virtually unknown. A series of experiments in showed a consistent response to S in some soils. In of 20 sites showed a significant response to S In 2008, 11 of 25 sites showed a significant response to S Average 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)
68 Iowa S rescue on corn. 40 lb S/acre as gypsum broadcast side dress early season after on set of deficiency symptoms. Sawyer, Site/Texture Yield w/o S Yield w/s 1 / loamy fine sand / loamy fine sand / loamy fine sand / loam (NS) 5 / silt loam / silt loam Across all sites
69 ANY crop is susceptible to S deficiency if soil and water conditions are favorable Most at risk Sandy soils Low organic matter Significant rainfall in fall or spring Higher landscape positions Least at risk Clay soils High organic matter Dry conditions in fall/spring Depressions
70 Zinc deficiency
71 99.9% water soluble ZnSO 4 on left/ 7& water soluble ZnOS0 4 on right From Amrani et al., CSU
72 Zinc in a low-testing soil in Nebraska (from Rehm and Schmitt, Rate of Zn, lb/acre Yield, bu/a % EDTA is 1 lb Zn per gallon.
73 Grain harvest logistics Combine Grain cart Trucking On farm drying and storage
74 If you address all of these issues, you will be a
75 Corn Grower!