World Dairy Expo

Options for Harvesting Corn Stover for Supplemental Feed

Kevin Shinners

University of Wisconsin

World Dairy Expo

• Why consider corn stover :

High feed costs

Abundant – 10 million tons in WI

Relatively low cost

High in effective fiber

Reduces residue

Introduction

World Dairy Expo

• Important issues with corn stover :

How to harvest, store and feed

Cost

Right feed additives

Introduction

World Dairy Expo

• How corn stover can be used :

Effective fiber source @ 2 – 5% of dietary DM

Feed for non-lactating and beef animals

Bedding

Biomass feedstock

Introduction

World Dairy Expo

• What are stover yields?

Rough rule of thumb:

1 : 1 ratio with grain weight

Every 35 bu ~ 1 ton stover

140 bu/ac ~ 4 ton/ac

Introduction

World Dairy Expo

Dry Bale Harvesting

World Dairy Expo

Dry Stack Harvesting

World Dairy Expo

• Issues with bale and stacker systems:

Slow field drying :

Low ambient temps, short day length

Short harvesting window

Frequent weather delays

Dry Stover Issues

World Dairy Expo

15%

30%

45%

60%

75%

90%

26-Aug 2-Sep 9-Sep 16-Sep 23-Sep 30-Sep 7-Oct 14-Oct

Moi

stur

e .

.. %

w.b

.

Grain

Stover

Stover Moisture

World Dairy Expo

Stover Drying

10%

20%

30%

40%

50%

2-Oct 4-Oct 6-Oct 8-Oct 10-Oct

Moi

stur

e .

.. %

w.b

.

0

2

4

6

8

10

12

Rainfall .. m

m

Untreated

Flat

Single Windrow

Double Windrow

World Dairy Expo

Stover Drying

10%

20%

30%

40%

50%

60%

10-Oct 12-Oct 14-Oct 16-Oct 18-Oct 20-Oct

Moi

stur

e .

.. %

w.b

.

0

2

4

6

8

10

12

Rainfall .. m

m

UntreatedFlatSingle WindrowDouble Windrow

World Dairy Expo

• Issues with bale and stacker systems:

Low productivity

Low density package

High ash content

Dry Stover Issues

World Dairy Expo

~6

~10

LRB

~3

~5

Stack

Density

~8lb. / ft3

LSB

~16tons / h

Productivity

Dry Stover Harvesting

World Dairy Expo

Dry Bale Harvesting

Ash .. % of DM

Baled

Standing

7.9

3.5

World Dairy Expo

• Issues with bale and stacker systems:

High storage losses

Non-uniform product

Dry Stover Issues

World Dairy Expo

Outdoor Storage of Bales

World Dairy Expo

14%20%Plastic Twine

Outdoors on Soil

37%

11%

2%

Wet Year

34%

29%

11%

5%

Dry Year

Stacks

Sisal Twine

Net Wrap

Indoors

Storage Losses

World Dairy Expo

Non-Uniformity of Bales

World Dairy Expo

Wet Stover Harvesting -Chopping

Chopped Wet Stover

World Dairy Expo

• Advantages of harvesting stover wet:

Eliminates field drying

Harvest right behind combine

Reduced soil contamination

Higher productivity

Easier to mix additives

Harvesting Wet Stover

World Dairy Expo

9 – 16

20 – 80

Typical WPCS

8 – 10Silo Density … lb. / ft3

Corn Stover

25 – 35Productivity … tons / h

Chopped Wet Stover

World Dairy Expo

Chopped Wet Stover

World Dairy Expo

0.6%0.9%1 – 3%Acetic

3.3%

4.1

3.8%

55%

Corn Stover

1.7%

4.5

1.4%

42%

5 – 10%

3.8 – 4.2

6 – 10%

60 – 65%

Typical WPCS

Lactic

DM Loss

pH

Acids

Moisture

Chopped Wet Stover

World Dairy Expo

Stover Particle Size

¾ – 1

8 – 10

Particle – Size .. in.

Round Bales and Stacks

Chopped

World Dairy Expo

Baled Wet Stover

World Dairy Expo

Baled Wet Stover

World Dairy Expo

2.3%0.5%Acetic

0.8%

4.4

2.9%

44%

Early

0.4%

5.1

1.2%

29%

Late

Lactic

DM Loss

pH

Acids

Moisture

Baled Wet Stover

World Dairy Expo

• Compared to dry systems, wet stover offers:

Less weather concerns

More uniform product

Easier mixing & feeding

Fewer storage losses

Potentially lower costs

Wet Stover Systems

World Dairy Expo

Stover Costs

$9Bales – Outdoors

$14

$14

$14

$28

Approximate cost per dry ton

Storage

Bales – Indoors

Round Bales

Chopped

Chopped – Bag

Harvest

World Dairy Expo

• How stover is fed :

Free-choice from bales or pasture

Sorting

Ground

TMR

Feeding Stover

World Dairy Expo

Stover Fractions

Stalk – 58% Leaf – 19%

Cob – 12%

Husk – 8%

After Grain Harvest / Before Stover Harvest

World Dairy Expo

Dry Bale Harvesting

Stalk – 49%Leaf – 36%

Cob – 3%Husk – 10%

After Stover Harvest

World Dairy Expo

76.3

46.7

4.0

7.7

Baled

3.8CP

41.9ADF

68.2

–

Chopped

NDF

Ash

After Storage Composition

World Dairy Expo

• To improve protein and digestible energy :

Wet and dry distillers grains

Grain

Whole-plant corn silage

Ammonia

Stover Feed Additives

World Dairy Expo

43.0

25.2

8.3

7.0

Stover + Corn*

70.2

45.0

8.3

12.3

Stover

14.4 CP

30.0ADF

57.5

8.4

Stover + DDG*

NDF

Ash

Feeding Stover

* - 50% of dietAfter Summer and Trenkle - 1998

World Dairy Expo

53.7

6.7

Stover + Corn*

39.1

5.7

Stover

59.4Digestibility .. %

6.4

Stover + DDG*

Intake .. lb. / day

Feeding Stover

* - 50% of dietAfter Summer and Trenkle - 1998

World Dairy Expo

Future of Stover Harvest

World Dairy Expo

Future of Stover Harvest

Cob, husk & leaf

Grain

Ear Snapper Head

World Dairy Expo

Future of Stover Harvest

All stover: Stalk, cob, husk & leaf

Grain

Whole-plant Head

World Dairy Expo

Future of Stover Harvest

World Dairy Expo

Options for Harvesting Corn Stover for Supplemental Feed

Kevin Shinners

University of Wisconsin