This document discusses the benefits of using cover crops in a corn/soybean/wheat rotation compared to tilling. Cover crops build organic matter, improve soil structure and nutrient cycling, increase water infiltration and holding capacity, and control weeds without tilling. They also support large populations of beneficial soil microbes and fungi. Legume cover crops such as hairy vetch and crimson clover fix nitrogen at rates of 50-200 pounds per acre. Cereal rye and radishes also provide weed suppression. Planting cover crop mixtures provides the greatest benefits for soil and following crop yields.

6. LONG TERM PASTURE
TILLED IN A
CORN/SOYBEAN/WHEAT
ROTATION

7. 
Loss of Organic
Matter


Soil structure
Soil microbial
biomass

Release of CO2

Soil Erosion

Why Till?

Weed Control

8. 

This is what separates us
(Missouri) from Central Iowa,
Illinois, Minnesota, Indiana,
etc
In these areas climatic
conditions favor the
accumulation of Organic
Matter
 Slower breakdown, long
history of deep rooted
native perennial plants

9. 
Nutrient Cycling




Water Dynamics



Nutrient Holding
Capacity
Pool of Nutrients
Food for soil organisms
Improves water
infiltration
Improves water holding
capacity
Structure


Reduces crusting,
compaction, erosion
Encourages root
development

11. 



Bacteria-100
million-1 Billion!
Fungal FilamentsSeveral Yards
Protoza-Several
Thousand
Nematodes-10-20

17. Courtesy Brady and Weil, 2012

20. Nodules-Symbiotic Relationship Between the Plant and the Bacteria.
Atmospheric Nitrogen is Fixed by the Bacteria For Use by the Plant.

22. 

Each Species of
Legume has a
Different Species of
Bacteria
You must match them
together.

23. 



A lot of biomass-2-3
tons/acre
Winter Hardy
High Nitrogen Fixation100 plus lbs/acre
Wide window of
planting
August-mid October
March
Hard Seed, late
maturing
 Problem When Wheat
is in the Rotation




24. 
Adapted from Gallagher, Penn State
2007
Time
Early (May 4)
Middle (May 15)
Late (May 31)
2008
Early (May 1)
Middle (May 14)
Late (May 29)
Hairy Vetch
lbs/acre %N
N lbs/acre
1,400
3.82
55
4,300
4.43
190
6,600
4.15
274
3,204
4,005
4,361
2.49
2.92
4.55
80
117
197
Corn Yield-0 N
113
132
140
92
121
79

25. Early May
Late May

26. 



Large Biomass
High N fixation-80120 lbs/acre
Plant fall or early
spring
Not as winter hardy

Seedling Disease
problems

28. 



Plant AugustSeptember
Early spring maturity
Not as much biomass
as Hairy Vetch or Peas
Can reseed
themselves

31. 



Inexpensive Seed
Rye is very winter
hardy
Rye tremendous dry
matter
Suppress weeds


Allelopathy or
Blocking Light
Good to mix with
legumes

32. 
Spring or Winter



Spring planted in the
fall will winter kill
Quick Growth in the
Fall
Great Companion
Crop

33. 



Cross between wheat
and cereal rye
Hardiness of cereal
rye
Good forage potential
Does not have the
allelopathic potential
as cereal rye

34. 





Plant in Fall
Overwinter-most of
the time
Deep Roots-5-6 ft
Scavenge Nitrogen
Dense matt controls
weeds
Can become a weed!

Herbicide resistance
problem

35. 
Late Summer Planted

Sequester Nitrogen

Loosen Soil

Weed Control?

36. Fall
Spring

39. 
Species
Crude Protein
ADF
NDF
%





Arrowleaf clvr
Field Pea
Cereal Rye
Ryegrass
Hairy Vetch
24.9 ab
23.2 b
19.1 c
19.1 c
26.4 a
21.5 bc
21.4 bc
25.1 a
24.7 ab
19.7 c
26.0 cd
30.2 c
46.4 a
41.8 b
25.1 d

40. 
Following Wheat

Summer Annual
Legumes
 Sunn Hemp
 Sesbania
 Cowpea
Cowpea

41. Sesbania
Sunn Hemp

42. Nutrient Scavenge, Loosen Soil, Weed
Control

43. Ohio State
University
Courtesy of
Steve Groff
Open
field
Tillage
Radish®
field
Soil compaction
decreased by >40%
Loosen SoilIncrease root
growth and
water
infiltration?

44. Gruver, et al, 2012

45. Williams and Weil, 2004

47. 100%
90%
80%
36 to 48
70%
29 to 36
60%
24 to 29
50%
18 to 24
40%
12 to 18
30%
9 to 12
3 to 9
20%
0 to 3
10%
0%
P
K
Clark and Reinbott, 2012

48. 140
120
lb K/acre
100
80
none
60
Crimson Clover
Rye
Hairy Vetch
40
20
0
0 to 3
3 to 6
6 to 12
Hargrove et al, 1986

49. 1.25 inch
2 inches
White and Weil, 2011

50. 150
Soybean
Soybean
130
Lbs/acre
110
90
Shoot
70
50
CornCorn
Root
30
10
-10
Dean and Weil, J Eniv. Quality 2009

54. 100
90
80
lbs/acre
70
60
50
Rye
40
Crimson Clover
30
Hairy Vetch
20
10
0
2
4
8
Weeks
12
16
From Wagger, 1989. Agronomy Journal

55. 
Weed Control



Smothering or
Allelopathy
Soil Health
-soil microbes
If no-till: soil and
water conservation

56. From Steve Groff
Cover Crop
No Cover Crop

63. 27,427
25,606

64. 
7 more Bushels/acre

Seed Cost-$45/acre


7 bushel/acre @
$13/bushel=$91/acre
Or about $46/acre
profit

65. 160
140
120
Hairy Vetch
187 lb N/acre
100
Crimson Clover
50 lb N/acre
80
Rye
36 lb N/acre
60
Control
40
20
0
0
50
100
From Ebelhar et al, 1986

66. 












Soybean Yield 2013
Cover Crops Overseeded into Corn Sept. 2012
Treatment
Yield
Bu/acre
Control
29
Hairy Vetch
24
Crimson Clover
28
Radish
27
Cereal Rye
36
Hairy Vetch+Rye
28
Crimson Clv. +Rye
33
Radish + Rye
29
Rye+Radish+HV+CC
27
Reinbott, 2013

67. 













Corn Yield 2013
Cover Crops Overseeded into Soybean September 2012
Corn
Treatment
Yield
Bu/acre
Control
175
Hairy Vetch
199
Crimson Clover
165
Radish
174
Cereal Rye
175
Hairy Vetch+Rye
187
Crimson Clv. +Rye
181
Radish + Rye
173
Rye+Radish+HV+CC
174
Reinbott, 2013

69. Brief

70. 







Hairy Vetch-$2.0/lb or $40-60/acre
Austrian Winter Pea-$0.73/lb or $29-44/acre
Crimson Clover-$1.2/lb or $24/acre
Radish-$4 lb or $32/acre
Cereal Rye-$0.23 or $14-21/acre
Annual Rye-$0.80 or $16/acre
Sunn Hemp-$2.5/lb or $50-75/acre
Sesbania-$2.4/lb or $48/acre

71. 




Hairy Vetch-$40@ 100 lb N/acre=$0.40/lb
Austrian Winter Pea-$29@80 lb
N/acre=$0.36/lb
Crimson Clover-$24@75 lb N/acre=$0.32/lb
Sunn Hemp-$50@80 lb N/acre=$0.62/lb
Sesbania-$48@80 N/acre=$0.60/lb