Oakes Irrigation Research Site

Carrington Research Extension Center * North Dakota State University

P.O. Box 531, Oakes, ND 58474-0531, Phone: (701) 742-2744, FAX: (701) 742-2700, E-mail:

Optimum Corn Stover Removal for Biofuels and the Environment

L. Besemann and H. Eslinger

The 2007 U.S. energy bill calls for 36 billion gallons of ethanol to be produced by 2020. In 2007 the U.S. produced 6.5 billion gallons of ethanol. If corn grain was able to supply 15 billion gallons of ethanol, 21 billion gallons of ethanol would have to come from cellulosic material (biomass) to meet the 2020 mandate. The production of 21 billion gallons of cellulosic ethanol will require 350 million tons of dry biomass. Presently, perennial grasses and corn stover are the most available. About 194 million tons of biomass is produced in U.S. production agriculture annually, with 75 million tons coming from corn stover. Therefore corn stover is being looked at to play a major role in cellulosic ethanol production.

Before we commit ourselves to using corn stover for fuel we need to study the environmental and economic consequences of this action. What effect will stover removal have on soil organic matter, soil erosion and ultimately sustainability of the land resource?

The objective of this study is to determine what rates of stover removal within different cropping systems are conducive to maintaining and possibly improving the productive capacity of the land while providing a renewable energy source.

MATERIALS AND METHODS

Rotations:

Block I: 2014 - field corn, 2013 – field corn, 2012 – field corn, 2011 - field corn, 2010 - field corn, 2009 ‑ field corn, 2008 – field corn, 2007 – field corn.

Block II: 2014 - soybean, 2013 – field corn, 2012 – soybean, 2011 - field corn, 2010 - soybean, 2009 ‑ field corn, 2008 – soybean, 2007 – field corn.

Block III: 2014 - field corn, 2013 – soybean, 2012 – field corn, 2011 - soybean, 2010 - field corn, 2009 – soybean, 2008 – field corn, 2007 - onion.

Soil:

Embden sandy loam, Hecla sandy loam and Maddock sandy loam.

Block I: pH=6.1; 2.1% organic matter; soil N 24 lbs/acre; soil-P and soil-K was very high; soil-S was very low.

Block II: pH=6.0; 2.1% organic matter; soil N 32 lbs/acre; soil-P and soil-K was very high; soil-S was low.

Block III: pH=6.7; 1.1% organic matter; soil N 27 lbs/acre; soil-P and soil-K was very high; soil-S was low.

Seedbed preparation:

Strip-till May 9 with an Orthman strip-till machine.

Hybrid:

Corn: Peterson 88A97SS RIB.

Variety:

Soybean: Peterson 14R11 RR2Y.

Planting:

Block I: Corn May 10 in 30-inch rows @ 33,000 seeds/acre.

Block II: Soybean May 27 in 30-inch rows @ 205,000 seeds/acre.

Block III: Corn May 10 in 30-inch rows @ 33,000 seeds/acre.

Fertilizer:

Block I: Twelve lbs N/acre and 40 lbs P2O5/acre as 10-34-0 via strip-till May 9. Stream bar 10 lbs N/acre and 23 lbs S/acre as 12 0-0-26 and 60 lbs N/acre as 28-0-0 May 22. Sidedress 135 lbs N/acre as 28-0-0 June 17.

Block II: Twelve lbs N/acre and 40 lbs P2O5/acre as via strip-till May 9.

Block III: Twelve lbs N/acre and 40 lbs P2O5/acre as via strip-till May 9. Stream-bar 10 lbs/N acre and 23 lbs S/acre as 12-0-0-26 and 60 lbs N/acre as 28-0-0 May 22. Sidedress 135 lbs N/acre as 28-0-0 June 17.

Irrigation:

Hand move sprinkler irrigation as needed.

Pest control:

Block I: Harness (2 pt/acre) May 22, Laudis (3 oz/acre) + AAtrex 9-O (0.5 lb ai/acre) + Destiny (0.05%v/v) + AMS (1½ lbs/acre) June 3.

Block II: Roundup Power Max (30 oz/acre) + AMS (10 lbs/100 gal) June 7. Roundup Power Max (20 oz/acre) + AMS (1 lbs/10 gal) June 25.

Block III: Harness (2 pt/acre) May 22; Laudis (3 oz/acre) + AAtrex 9-0 (0.5 lb ai/acre) + Destiny (0.05% v/v) + AMS (1½ lbs/acre) June 3.

Remote sensing:

Remote sensing was achieved with an Opti-Sciences CCM 200 Plus chlorophyll meter and a Holland Crop Circle ACS active canopy sensor (normalized difference red edge ‑ NDRE).

Harvest:

Block I: : Hand harvested the entire length (27 feet) of rows 6 and 7 from each plot on October 17.

Block II: October 8 with a 4400 JD combine (48 rows 108 feet long, recorded with a weigh wagon).

Block III: Hand harvested the entire length (27 feet) of rows 6 and 7 from each plot on October 17.

RESULTS BLOCK I (Corn/Corn) - 2014

Corn stover was removed at the 33, 67 and 100 percent removal rates in block I (corn/corn rotation). Stover removal had no significant effect on grain yield, moisture and test weight at the 95% confidence level. Stover removal had no effect on chlorophyll readings (Opti-Science CCM 200), Normalized Difference Red Edge (NDRE) indice (Holland Crop Circle ACS 430) and stalk nitrate-N (Table 1) at the 95% confidence level. Longer term data from 2009 to 2014 is presented in Table 2. The effect on revenue for the higher yield of the 100 percent removal rate compared to the 0 percent removal rate when the cost of N, P and K are accounted for is shown in Figure 1.

RESULTS BLOCK II (Soybean/Corn) - 2014

All soybean plots were combine harvested and bulked. The soybeans yielded 51.0 bu/acre at 11.1% moisture (51.2 bu/acre @ 13 %) and had a test weight of 58.5 lbs/bu.

RESULTS BLOCK III (Corn/Soybean) - 2014

Stover removal rates of 33, 67, and 100 had no effect on grain yield, moisture or test weight (Table 3).

Figure 1. The net return when the fertility cost leaving the field is subtracted from the yield advantage in 100 percent removal plots compared to 0 percent removal plots for corn on corn from 2008 to 2013 (Mean) at the Oakes Irrigation Research Site.

Table 1. The affect of corn stover removal from 0 to 100% on grain yield and other agronomic parameters for corn on corn plots in 2014.

Grain

Stalk DM

Chlorophyll

Stover

Grain

Yield

Harvest

Test

Stalk DM

Removal

Meter

Stalk

Fall soil

Seed

Emerge

Silk

Mature

Nutrients in stover²

Nutrient Value

Removal

Yield¹

2009-14

Moisture

Weight

Removal²

2008-13

Reading³

NDRE⁴

Population

Nitrate-N

Oil

Protein

Starch

Date

20142

2008-2014

bu/ac

lb/bu

------ ton/ac ------

4-Aug

plants/ac

ppm

lbs

---------%------------

---- lb/acre ----

------ $/ac ------

191.9

216.1

16.5

51.9

0.0

51.5

0.3346

32831

1606

1.8

9.4

74.2

26-May

26-Jul

25-Sep

208.0

221.7

15.7

52.0

2.1

2.3

51.8

0.3462

34364

1896

1.7

9.1

74.5

25-May

24-Jul

24-Sep

204.3

223.3

16.2

52.2

2.8

3.5

53.2

0.3476

34284

1850

1.8

9.1

74.4

25-May

24-Jul

24-Sep

100

208.3

223.8

15.9

52.4

4.4

5.3

53.1

0.3461

33558

1603

1.7

9.2

74.6

25-May

23-Jul

24-Sep

Mean

203.1

16.1

52.1

2.3

52.4

0.3436

33759

1738

1.8

9.2

74.4

25-May

24-Jul

24-Sep

C.V. (%)

4.2

5.0

2.7

6.1

2.7

1.8

3.6

15.4

48.6

19.7

2.9

0.7

13.8

26.9

28.0

19.0

LSD 0.10

11.1

0.18

0.0078

21.6

0.65

1.5

5.7

0.6

7.6

LSD 0.05

0.23

26.6

0.80

1.9

7.0

0.8

9.4

Planting Date = May 10; Harvest Date = October 17 ; Previous Crop = Corn.

Fertilizer Rate lbs/acre = 242 N, 40 P₂O₅, 23 S; Irrigation = 8.0 inches.

¹Yield adjusted to 15.5% moisture.

² Corn stover removed spring of 2014 from 2013 corn crop.

³Opti-Science CCM 200.

⁴Holland Crop Circle ACS active canopy sensor (normalized difference red edge) - NDRE.

Table 2. Corn on Corn Stover Removal - NDSU Oakes Irrigation Research site 2009-2014.

Stover

Grain

Harvest

Test

Chlorophyll

Reading

Stalk

Grain

Silk

Mature

Removal

Yield

Moisture

Weight

Reading

NDRE

Nitrate-N

Protein

Date

bu/ac

lb/bu

ppm

216.1

21.7

54.0

0.3605

2434

8.6

7/24

9/29

221.7

20.9

54.6

55.1

0.3624

2931

8.5

7/23

9/28

223.3

20.9

54.6

56.1

0.3636

2920

8.5

7/22

9/27

100

223.8

20.3

54.9

56.1

0.3594

3143

8.6

7/21

9/27

Mean

221.2

Table 3. The affect of corn stover removal from 0 to 100% on grain yield and other agronomic parameters for corn on soybean plots in 2014.

Year

Grain

Stover

Grain

Yield

Harvest

Test

Nitrate-N

Seed

Emerge

Silk

Mature

Removal

Yield¹

2009-14

Moisture

Weight

Chlorophyll²

NDRE³

Stalk test

Fall Soil

Population

Oil

Protein

Starch

Date

bu/ac

lb/bu

4-Aug

ppm

lbs

plants/ac

------------%-------------

220.5

227.2

15.7

53.2

52.7

0.3535

1800

32670

2.2

9.3

73.7

25-May

23-Jul

24-Sep

221.3

222.4

15.6

53.4

52.1

0.3532

1428

33315

2.0

9.2

74.1

25-May

22-Jul

24-Sep

205.4

222.2

15.1

53.1

48.8

0.3481

1156

33073

2.1

9.2

73.9

25-May

22-Jul

24-Sep

100

222.4

225.7

15.4

53.5

54.3

0.3536

1628

33719

1.9

9.3

74.2

25-May

22-Jul

24-Sep

Mean

217.4

15.5

53.3

51.9

0.4

1503

33194

2.1

9.2

74.0

25-May

22-Jul

24-Sep

C.V. (%)

5.2

5.3

1.2

5.9

1.8

45.5

56.6

2.5

11.0

2.7

0.6

LSD 0.10

LSD 0.05

Planting Date = May 10; Harvest Date = October 17 ; Previous Crop = Soybean

Fertilizer Rate lbs/acre = 242 N, 40 P₂O₅, 23 S; Irrigation = 8.0 inches.

¹Yield adjusted to 15.5% moisture.

²Opti-Science CCM 200.

³Holland Crop Circle ACS active canopy sensor (normalized difference red edge) - NDRE.

Oakes Irrigation Research Site

Other corn Studies 2014

Corn hybrid performance trial - dryland

Corn hybrid performance trial - irrigated

Strip-till continuous corn N-rate

Strip-till corn/soybean rotation corn N-rate