Reconsidering Red Clover

Bill Deen, Dave Hooker, Amelie Gaudin

Presented at 8th Annual MCCC Meeting

February 28, 2013

London, Ontario

Addition of winter wheat provides

”niche” for cover crop opportunity In a corn/soybean/winter wheat rotation winter wheat

rotation often perceived as contributing the least to

profitability…but perhaps it is equal or more

Longterm trials at Elora Research Station and

Ridgetown Campus demonstrate that addition of winter

wheat provides

Increase of yield and yield stability of corn and soybean

Reduction of corn N requirement

Net return from wheat straw

An opportunity for cover crop and associated benefits

Elora Research Station : 1625 acres, silt loam soil, 900mm annual rainfall, 2700-2800 CHU

Long-term rotation

trial, 2011

• Initiated in 1980

• Rotations – CCCC, AAAA, CCAA, CCSS, CCSW, CCSW(rc), CCOB, CCO(rc)B(rc)

• Conventional tillage and no-till

Corn

Soybean

Alfalfa

Barley

Wheat

NT CT

25

30

35

40

45

50

55

SSCC SWCC SW(rc)CC

So

yb

ean

yie

ld (

bu

/ac

) MP

NT

2000-2011

The “Rotation Effect” Wheat on Soybean Yields - Elora

100

110

120

130

140

150

160

170

180

2n

d y

ear

co

rn y

ield

(b

u/a

c

@1

5.5

%)

MP

NT

2000-2011

100

110

120

130

140

150

160

170

180

Irst

year

co

rn y

ield

(b

u/a

c

@1

5.5

%)

MP

NT

The “Rotation Effect” Wheat on Corn Yields - Elora

• Established 1995 (by Doug Young)

• 5 Crop Rotations

• C-C

• S-S

• C-S

• C-S-W

• S-W

• 4 N treatments in corn and wheat

• Red clover underseeded in wheat plots

Ridgetown Long-Term Tillage-Rotation

133c

150b 154

152b 150b

156b 159

156b

178a

186a

157

175a

100

110

120

130

140

150

160

170

180

190

200

Gra

in Y

ield

(b

u/a

c)

2009 2010 2011

1. The “Rotation Effect” Wheat on Corn Yields Ridgetown 2009-12

C-C

C-S

C-S

-W

2012

C-C

C-S

C-S

-W

C-C

C-S

C-S

-W

C-C

C-S

C-S

-W

Note: Mean separation within year (p=0.05)

50c

42b

60b

73c

55b

43b

62b

78b

60a

47a

69a

86a

30

40

50

60

70

80

90

Rotation

Seed

Yie

ld (

bu

/ac)

2009

Averaged Across Tillage and Corn N treatments at Ridgetown. Est. 1991; letters within year statistically different at p=0.05 Source: Hooker et al., 2011 (UofG Ridgetown)

2010 2011

C-S

C-S

-W

2012

Note: Mean separation within year (p=0.05)

S-S

C-S

C-S

-W

S-S

C-S

C-S

-W

S-S

C-S

C-S

-W

S-S

1. The “Rotation Effect” Wheat on Soybean Yields Ridgetown 2009-12

186

157

175 173b

198

162

184 181a

100

120

140

160

180

200

220

Gra

in Y

ield

(b

u/a

c)

2010 2011

Corn Yields after Wheat +/- Red Clover, Ridgetown 2010-12

C-S

-W

C-S

-W(r

c)

2012

C-S

-W

C-S

-W(r

c)

C-S

-W

C-S

-W(r

c)

C-S

-W

C-S

-W(r

c)

Ave

Seed

Yie

ld (

bu

/ac)

No-Till Conventional Till

61c

56b

63bc

59b

68a 66a

67ab 68a

30

35

40

45

50

55

60

65

70

75

C-S

-W(r

c)

S-S

C-S

C-S

-W

C-S

-W(r

c)

S-S

C-S

C-S

-W

Note: Mean separation within tillage system (p=0.05)

Soybean Yields with Wheat +/- Red Clover, Ridgetown 2010-12

Gaudin et al, 2013. Agron.

Operating expenses taken from 2012 OMAFRA Crop Budgets -

(http://www.omafra.gov.on.ca/english/busdev/facts/pub60.htm)

Nutrient price taken from October 2012 - Ridgetown Input Price Survey -

http://www.ridgetownc.uoguelph.ca/research/research_reports_topic.cfm?ref=FARM_INPUT_PRICES

Corn Soy

Yield (bu/ac) 175 50

$/bu 5.25 12.00

Gross Revenue ($/ac) 918.75 600.00

Operating Expenses ($/ac) 477.00 231.00

Gross Margin ($/ac) 441.75 369.00

Estimated gross margin of C/S rotation

Operating expenses taken from 2012 OMAFRA Crop Budgets -

(http://www.omafra.gov.on.ca/english/busdev/facts/pub60.htm)

Nutrient price taken from October 2012 - Ridgetown Input Price Survey -

http://www.ridgetownc.uoguelph.ca/research/research_reports_topic.cfm?ref=FARM_INPUT_PRICES

Estimated gross margin of C/S/W rotation – No red clover Corn Soy Wheat

Yield (bu/ac) 175 50 80 Straw yield 2500 lbs

$/bu 5.25 12.00 7.00 Straw value in winrow 0.04 $/lb

Gross Revenue ($/ac) 918.75 600.00 560.00 Nutrient removal 0.007 $/lb

Operating Expenses ($/ac) 477.00 231.00 274.00 Net straw value 0.033 $/lb

Gross Margin ($/ac) 441.75 369.00 286.00

Adj Gross Margin ($/ac) 487.69 417.00 368.50

GM Diff ($/ac) 45.94 48.00 82.50 Ncorn N rate reduction 75 lbs/ac

True Gross Margin ($/ac) 441.75 369.00 462.44 Nitrogen cost 0.5 $/lb

Red clover success rate 0.00

Adjustments

Rotation Adjustment (%) 5 8 0

Straw Revenue ($/ac) 82.50

Red Clover (adj for stand success) (%) 0 0 0

Red clover N Adj (adj for stand success) ($/ac) 0.00

Double crop revenue - oat/pea Bonus

Straw Value

Red cover N credit

Operating expenses taken from 2012 OMAFRA Crop Budgets -

(http://www.omafra.gov.on.ca/english/busdev/facts/pub60.htm)

Nutrient price taken from October 2012 - Ridgetown Input Price Survey -

http://www.ridgetownc.uoguelph.ca/research/research_reports_topic.cfm?ref=FARM_INPUT_PRICES

Estimated gross margin of C/S/W rotation – Red clover Corn Soy Wheat

Yield (bu/ac) 175 50 80 Straw yield 2500 lbs

$/bu 5.25 12.00 7.00 Straw value in winrow 0.04 $/lb

Gross Revenue ($/ac) 918.75 600.00 560.00 Nutrient removal 0.007 $/lb

Operating Expenses ($/ac) 477.00 231.00 274.00 Net straw value 0.033 $/lb

Gross Margin ($/ac) 441.75 369.00 286.00

Adj Gross Margin ($/ac) 571.13 447.00 368.50

GM Diff ($/ac) 129.38 78.00 82.50 Ncorn N rate reduction 75 lbs/ac

True Gross Margin ($/ac) 441.75 369.00 575.88 Nitrogen cost 0.5 $/lb

Red clover success rate 1.00

Adjustments

Rotation Adjustment (%) 5 8 0

Straw Revenue ($/ac) 82.50

Red Clover (adj for stand success) (%) 5 5 0

Red clover N Adj (adj for stand success) ($/ac) 37.50

Straw Value

Red cover N credit

Overcoming red clover non-uniformity

Red clover broadcast timing

Drilling versus broadcasting

Wheat row spacing

Wheat tillage system

Wheat N rate

Drought tolerance

CCSW(rc) – no-till CCSW(rc) – Conv till

0 kg N ha-1

0

1000

2000

3000

4000

5000

6000

7000

8000

0 20 40 60 80 100 120 140

Wh

ea

t yie

ld (

kg

ha

-1)

N rates

CNR CTB

CWR DHG

DHY DNR2

DSH INR2

PJF SNR1

SNR2

Wheat biomass N response curves

R² = 0.3745

0

1000

2000

3000

4000

5000

6000

1000 3000 5000 7000 9000

Fin

al re

d c

love

r b

iom

ass

(kg

ha

-1)

Wheat yield (kg ha-1)

0 N

40 N

80 N

120 N

Effect of wheat yield on red clover biomass

0

1000

2000

3000

4000

5000

6000

7000

0 20 40 60 80 100 120 140 160 180 200

Wh

ea

t yie

ld o

r re

d c

love

r b

iom

ass (k

g h

a-1

)

Wheat yield Final red clover biomass

Yield at MERN = 5910 kg ha-1

RC biomass at MERN = 2119

kg ha-1

MERN = 104 kg N ha-1

0

100

200

300

400

500

0 20 40 60 80 100 120 140 160 180 200

Re

turn

to

N (

$ h

a-1

)

N rates

Effect of N on RC biomass and stand count distribution

0

5

10

15

Fre

qu

en

cy

(n=

35

)

0N

0

5

10

15

Fre

qu

en

cy

(n=

35

)

40 N

0

5

10

15

Fre

qu

en

cy

(n=

35

)

80 N

0

5

10

15

0-500 1000 2000 3000 4000 5000 6000

Fre

qu

en

cy

(n

=3

5)

Red clover biomass class (kg ha-1)

120 N

0

2

4

6

8

Fre

qu

en

cy

(n=

30

)

0

5

10

Fre

qu

en

cy

(n=

30

)

0

2

4

6

8

10

Fre

qu

en

cy

(n=

30

)

0

5

10

15

0-5000 50000 100000 200000 300000 400000 500000 600000

Fre

qu

en

cy

(n=

30

)

Red clover stand count class (plt ha-1)

Poor red clover stands – variable N application? Key questions:

• Can ground-based or UAV image systems map variable stands?

• What is the relationship between image and RC biomass?

• What is the relationship between RC biomass and nitrogen credit?

• Does N application equipment match spatial scale of RC variability?

• Is it economical?

0

50

100

150

200

250

300

0 20 40 60 80 100 120 140 160 180 200 220

Nitrogen Rate (kg-N ha-1

)

Re

turn

to

Nit

rog

en

($

ha

-1)

Corn following red clover (MERN = 99 kg N/ha)

Corn (MERN = 150 kg N/ha)

$0 to -$25 ha-1

of MERN

$0 to -$25 ha-1

of MERN

Effect of nitrogen rate on returns for corn, average of

19 pair-wise comparisons between 1990-99. (N @ 1.00

$Cdn kg-1, corn @ 100 $Cdn t-1)