Make Cover Crops & Manure Pay: coach farmers to success

Sarah CarlsonPractical Farmers of Iowa

Strategic Initiatives Directorsarah@practicalfarmers.org

515-232-5661

ALL TOO COMMON….

WHO IS

PRACTICAL FARMERS

OF IOWA?

Equipping farmers to build resilient farms and

communities.

Member-led, non-profit organization~3,400 members

Outputs•51 farmers conducted•71 projects

Farmer-Led Research

Equipping farmers to build resilient farms and communities.

Farmer-Led

Learning

Outputs•54 PFI farmer members and staff•99 learning opportunities •6980 attendance

Equipping farmers to build resilient farms and communities.

Barriers

to reaching

goals

WHY ARE

COVER CROPS A MUST?

Soil Nitrate Production vs. Crop Nitrate Uptake

In the shaded areas, the soil produces nitrate, but there is no crop to use it.

As a result, some nitrate is lost to waterways.

March February

Rate of soil nitrate production from native soil organic matter

Rate of corn or soybean nitrate uptakeThe majority of nitrate used by corn and soybean comes from soil nitrate production. Corn gets the difference from fertilizer while soybean gets the difference from legume fixation of atmospheric nitrogen.

Regional Research Projects (*SI)

488,626 A

591,880A

794,724ARecent Projects•Mapping Cover Crops ‘15 – ’16•Economics of Cover Crops•ASA Cover Crops for CCAs

Equipping farmers to build resilient farms and communities.

Land OwnershipCover Crop Adoption

Rye cover crop spring 2013(?)Van Horne

High disturbance vs.Low disturbance

COACH COVER CROP

RECOMMENDATIONS

TO SUCCESS

1.Control Seed Costs2.Control Herbicide Costs3.Avoid Cover Crop Establishment Failures4.Avoid Redundant Expenses5.Avoid Corn Yield Drag6.Realize Soybean Yield Gains7.Feed Cover Crops

Make Cover Crops Pay

Oats: $8/AMix: $32/A Mix: $14.25/A

Rye: $10/A

1. Control Seed Costs

• 49 cover crop entries• 10-16 locations• 5 years

GRASS:Cereal Rye

BRASSICAS:Rapeseed

LEGUMES:Hairy Vetch

Cover Crop Variety Trial

2. Control Herbicide Costs

Early~10 days prior to planting soybeans

Latewithin 1 day of planting soybeans

$30+$10+

Early termination $/ac Late termination $/ac

Glyphosate (40 oz/ac) 5.16 Glyphosate (32 oz/ac) 4.13

Class Act adjuvant 3.76 Class Act 3.76

Application 7.35 Application 7.35

Glyphosate (32 oz/ac) 4.13 Flexstar GT (3.5 pt/ac) 13.76

Class Act 3.76 AMS 0.60

Application 7.35 Destiny 0.80

Flexstar GT (3.5 pt/ac) 13.76 Application 7.35

AMS 0.60

Destiny adjuvant 0.80

Application 7.35

Mech. cultivation 13.50

TOTAL 67.52 TOTAL 37.75

Diff. = $29.77

Herbicide carryover into fall• Cereal rye only affected by 2x Dual II Magnum (Halex GT

anecdotally)

• Vetch, lentil, and radish affected by:

– Balance Flexx, Corvus, & Hornet

• Atrazine, Callisto, & Laudis caused no injury

3.Avoid Cover Crop Failure

Armstrong, et al., Illinois State University

4.Avoid Redundant Expenses

• Fall+cc -70% fall DAP & anhydrous + 30% sidedressanhydrous

• Fall-70% fall DAP & anhydrous + 30% sidedress anhydrous• Spring + cc-20% fall DAP + 80% anhydrous• Spring-20% fall DAP + 80% anhydrous• Zero control: no N & no cc

5.Avoid Corn Yield Drag

12 participating farmers from 2008 – 2017 (5 remaining)

Corn yields, Cover vs. No cover

-50

-40

-30

-20

-10

0

10

20

30

2009 2010 2011 2012 2013 2014 2015 2016 2017

bush

els

per a

cre

Yield advantage

Yield drag*

*+

*

*

*

* P ≤ 0.05+ P < 0.10

Camelina showed no increased Pythium incidence

Cover crop terminated

May 3

Cover crop terminated

Apr. 17

QUESTION: When should I terminate cereal rye cover crop before planting soybeans?

CC herbicide terminated 21 & 3 days before planting 5/8/2017

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

Corn Soybean Soybean

Sloan Sieren

poun

ds p

er a

cre

Farm and Previous Crop

Cover crop biomass Apr. 17 termination

May 5 termination

6.Realize Soybean Yield Gain

7.Feed Cover Crops

Cover Crop Decision Tree

If we want to turn this….into this

1.Control Seed Costs2.Control Herbicide Costs3.Avoid Cover Crop Establishment Failures4.Avoid Redundant Expenses5.Avoid Corn Yield Drag6.Realize Soybean Yield Gains7.Feed Cover Crops

Make Cover Crops Pay

Sarah CarlsonPractical Farmers of Iowa

Strategic Initiatives Directorsarah@practicalfarmers.org 515-232-5661

Take home messages

WHO is Practical Farmers of Iowa?

WHY are cover crops a must?

IMPROVE Cover Crops Recommendations

Sarah CarlsonPractical Farmers of Iowa

Strategic Initiatives Director

sarah@practicalfarmers.org 515-232-5661

“$30-$35/A cover crop cost

protects a $5000-$10,000/A

asset”

Iowa farmer new to cover crops

QUESTION: How does a cereal rye cover crop

affect corn and soybean yields?

First strips established in Fall 2008 at six

commercial farms.

Corn yields, Cover vs. No Cover

*

*

-25-20-15-10-505

10152025

Holstein Jefferson Plainfield WestChester

NewMarket

CoonRapids

Jefferson

2015 2016 2017

bush

els

per a

cre

Yield advantage

Yield drag

* P ≤ 0.05

Cover crop terminated

May 3

Cover crop terminated

Apr. 17

QUESTION: When should I terminate cereal rye cover crop before planting soybeans?

Corn-on-Corn Corn following Soybean

Low High Low High

76#N FallManure

76#N FallManure

15#N Before Planting

15#N Before Planting

35#N @ planting

35#N @ planting

35#N @ planting

35#N @ planting

70#N @ side-dress

90#N @ side-dress

100#N @ side-dress

120#N @ side-dress

181#N Total 201#N Total 150#N Total 170#N Total

Early vs. Late Killed Cereal Rye & Nitrogen Rate Effect on Corn

CC herbicide terminated 21 & 3 days before planting 5/8/2017Cover Crop:15 W. Barley, 50 W. Wheat; 20 Oats; 5 Rapeseed

Cover Crop:20 W. Barley, 50 W. Wheat; 20 Cereal Rye

Corn-on-Corn Corn following Soybean

Low High Low High

76#N FallManure

76#N FallManure

15#N Before Planting

15#N Before Planting

35#N @ planting

35#N @ planting

35#N @ planting

35#N @ planting

70#N @ side-dress

90#N @ side-dress

100#N @ side-dress

120#N @ side-dress

181#N Total 201#N Total 150#N Total 170#N Total

Early vs. Late Killed Cereal Rye & Nitrogen Rate Effect on Corn

CC herbicide terminated 21 & 3 days before planting 5/8/2017Cover Crop:15 W. Barley, 50 W. Wheat; 20 Oats; 5 Rapeseed

Cover Crop:20 W. Barley, 50 W. Wheat; 20 Cereal Rye

Early Termination (19DBP) Late Termination (1DBP)

70#N as UAN @ planting

70#N as NH3 @ strip-till

35#N UAN as herbicide carrier

70#N as NH3 @ strip-till

70#N as UAN @ side-dress

70#N as UAN @ side-dress

105#N as UAN @ side-dress

35#N UAN as herbicide carrier

35#N UAN as side-dress

140#N Total 140#N Total 140#N Total 140#N Total

Cover Crop:97#/A Cereal Rye

0

1,000

2,000

3,000

4,000

5,000

6,000

7,000

Corn Soybean Soybean

Sloan Sieren

poun

ds p

er a

cre

Farm and Previous Crop

Cover crop biomass Apr. 17 termination

May 5 termination

1.CC 21 DBP = 1000 lbs/A CC 3 DBP = 3000 lbs/A2.CC 21 DBP = 1200 lbs/A CC 3 DBP = 5000 lbs/A3.CC 21 DBP = 2000 lbs/A CC 3 DBP = 4000 lbs/A

1.

2.3.

1.

2.

3.

2.

1.

“$30-$35/A cover crop cost

protects a $5000-$10,000/A

asset”

Iowa farmer new to cover crops