1. Tim Reinbott, Kerry Clark, Leslie Touzeau
573-884-7945
Reinbottt@Missouri.edu

2. Jeff Moyer at Rodale

5. LONG TERM PASTURE NATIVE
WARM SEASON GRASSES
TILLED IN A
CORN/SOYBEAN/WHEAT
ROTATION

6. No-Till Grain Sorghum Into Hairy Vetch Residue
Tillage Has Destroyed Soil Structure

9.  Cash Crop All Three
Years?
 Weed Control
Strategies-Using
Cover Crops
 Tillage vs No-Tillage

10.  Always use a
polyculture cover crop-
legumes, grasses, and
brassicas
 Treatment 1: always
use a crop that is
mowed or incorporated
into the soil-no cash
crop-includes sorghum
x sudangrass (SXS)

11.  Treatment 2-cover
crops first year (SXS):
cash crops 2nd (grain
sorghum) and 3rd
years.
 Treatments 3 and 4:
no-till-soybean/grain
sorghum or
soybean/corn rotation
 Treatments 5 and 6-
same as treatments 3
and 4 except tilled
 Treatment 7: tilled
sorghum x sudan first
year followed by
wheat/soybean/corn

14. Cover Crops and Weed Control-Both Physical
and Natural Chemical Controls
Cowpea
Weedy plot with
no cover crop

15. 0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
buckwheat cowpeas fallow sesbania ss sunn hemp turnip winter
radish
WeedCoverAsPercentageOfTotalLandArea
Cover Crop
Weed Control In Summer
Cover Crops
Clark and Reinbott, 2012

16. Courtesy of Iowa State

18. On The Left Cover Crop, Right No Cover CropPlanting Into Standing Cover Crop

19. After Tillage Radish-No Annual WeedsLight Inhibition From The Cover Crop

20. >
>
<
Teasdale and Mohler, 2000

21. From Peachy, et al, 1999

22. Teasdale, 1996

23. Early May 1500 lbs Late May 7,000 lbs
Promotes a Bacteria
Dominant Soil Promotes a Fungi
Dominant System

25. Your text here
From Peachy, et al. 1999

26.  Weeks After Transplanting
 Treatment 2 4 6 8
 lbs/acre
 Bare Ground 109 2818 13,465 12,376
 Rye-2 WBP 5 120 572 2042
 Rye-1 WBP 3 28 320 1556
WBP=Weeks Before Planting-how many weeks prior to
Tomato Transplanting was cover crop terminated
Smeda and Weller, 1996

27.  As Rye Biomass
Changes From 2,000
lb/acre to 8-10,000
lb/acre Weed
Biomass Decreases
Linearly.
Nord, et al. 2011
WeedBiomass,lbs/acre
2008
2009
0
6,000
0
6,000

28.  Delay Cover Crop
Destruction
 Crops that Can Be
Planted Later-
Soybean, Sorghum, Sun
flowers
 Plant Higher Rate of
Cover Crops
 Earlier Maturing Corn
 -so we can plant later
 Plant cover crop in fall
earlier

29. Courtesy of Steve Groff

30. Lauer, 1996

31.  1x=100 lb/acre
Oat/legume
 2x=200 lb/acre
Oat/Legume
 3x=300 lb/acre
Oat/Legume
Brennan, et al., 2009
1x
2x
3x

32.  A Two-Year Rotation
(top) corn/soybean
large number of weeds
 Increasing Length of
Rotation Decreased
Weed Biomass-Middle
and Bottom
 Including Hay for two
years (bottom) In
Rotation Decreased
Weeds-Bottom open
symbols
Teasdale, et al, 2004
Two-Year Rotation
Three Year
Four-year

34. DAY OF DESICCATION
5 DAYS LATER
Flailed Rolled Rolled Flailed

35. 0
10
20
30
40
50
60
70
80
90
100
chop roll chop roll chop roll chop roll
before cc destroyed same day cc destroyed 1 week after cc
destroyed
2 weeks after cc
destroyed
Plantcountper10feet
Corn germination when planted into rye cover crop

37.  Crop Crop Stand Stand
 System 2012 2013 2012 2013
plants/acre
 Corn/soy tilled soybean corn 81,370 20,904
 Corn/GS/soy soybean GS 86,771 47,034
 Corn/soy no-till soybean corn 61,492 22,646
 GS/Soybean no-tillsoybean GS 66,196 29,614
 GS=Grain Sorghum

38. Rolled and Then PlantedPlanted Directly and Then Rolled

40.  Rolled Standing
 Treatment Pop. Pop
plants/acre
 Control 24,347 28,855
 Hairy Vetch 29,563 34,813
 Aust. Winter Pea 23,884 26,926
 Cereal Rye 25,774 24,315


42. 6,900 lb Cover CropLess Than 4000
lb Cover Crop

44.  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
Reinbott, 2013

45. 
 Weed Cover Crop SxS 2013
 System 2012 2013 Biomass Biomass Biomass Grain Yield
 Lbs/acre lbs/acre
 Cover Crop Only SxS SxS 83 4891 41,384
 Modified Cover Crop SXS GS 2279 4112 20
 Modified Conv. Till SXS wheat 209 28
 Corn/soy tilled soybean corn 2299 5490 77
 Corn/sorg/soy soybean GS 2788 7071 13
 Corn/soy no-til soybean corn 3143 8712 49
 Sorghum/Soybean soybean GS 3129 6268 4
Clark and Reinbott, 2013

54.  Natural Compounds
 Stems, leaves, roots
 Sorghum, Cereal
Rye, Walnut trees
 Can inhibit
germination and
growth of other plants

55. Weston et al., 2013

57. Kelton, et al.,

58. 
 Weed Cover Crop SxS 2013
 System 2012 2013 Biomass Biomass Biomass Grain Yield
 Lbs/acre lbs/acre lb/acre lb/acre lb/acre bu/acre
 Cover Crop Only SxS SxS 83 4891 41,384
 Modified Cover Crop SXS GS 2279 4112 20
 Modified Conv. Till SXS wheat 209 28
 Corn/soy tilled soybean corn 2299 5490 77
 Corn/sorg/soy soybean GS 2788 7071 13
 Corn/soy no-til soybean corn 3143 8712 49
 Sorghum/Soybean soybean GS 3129 6268 4
 SxS=Sorghum x Sudan
 GS=Grain Sorghum

63.  Weed Cover Crop SxS 2013
 System 2012 2013 Biomass Biomass Biomass Grain Yield
 Lbs/acre lbs/acre lb/acre lb/acre lb/acre bu/acre
 Cover Crop Only SxS SxS 83 4891 41,384
 Modified Cover Crop SXS GS 2279 4112 20
 Modified Conv. Till SXS wheat 209 28
 Corn/soy tilled soybean corn 2299 5490 77
 Corn/sorg/soy soybean GS 2788 7071 13
 Corn/soy no-til soybean corn 3143 8712 49
 Sorghum/Soybean soybean GS 3129 6268 4
 SxS=Sorghum x Sudan
 GS=Grain Sorghum

64.  Cover Crops Can Reduce Weed Competition:
 Light Inhibition
 Competition
 Releasing Natural Chemicals-Allelopathy
 Tillage Increases Weed Germination and
Competition
With Heavy Weed Pressure Year Around Cover Crops
May Need to Be Utilized. Forgoing a Cash Crop

65.  Planting Later and Using A Shorter Season
Cultivar Maybe Best to Help Reduce Weeds.
 Small Seeded Vegetables Have a Hard Time In
No-Till Cover Crops
 Incomplete Cover Crop Kill Can Inhibit
Vegetable Yield

67. 67
Kristen Veum and Robert Kremer

68.  SOM is derived from
 Plant residue (both
litter and roots)
 Animal remains and
excreta
 Living soil microbes
(microbial biomass)
 Over time fresh
organic material is
transformed into soil
organic matter
Crop
Residues
Bacteria
Fungi
Actinobacteria
SOM
68

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

71. 3000
3500
4000
4500
5000
5500
6000
6500
7000
7500
80001900
1910
1920
1930
1940
1950
1960
1970
1980
1990
Year
SoilC(gm-2)
Conventional
Tillage
Reduced
Tillage
53% of 1907
61% of 1907
71

72.  20 – 40% of SOM is lost on cultivation
 Management effects on SOM
 Tillage (disturbance) 
 Chemical Fertilization 
 Manure 
 Residue Retention 
 Crop 
 Crop Rotation 
 Cover Crop 
72
Decline in SOC from Sanborn
Field Plots showing increase
following the return of residues
beginning in 1950

73. 73

78. Slake Test
Fungi Hyphae

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

80. 0
500
1000
1500
2000
2500
3000
Biomass(mg/g)
Cropping Type
PLFA Analysis at Bradford Research Center
Bacteria
Actinomycetes
Fungi
Protozoa
No Protozoa in Corn/Soybean Rotations.
Micro Organism biomass highest in perennial cover
Bradford Research Center, 2012

81. 0
50
100
150
200
250
300
350
400
450
500
Soybean Switchgrass NT Corn Hedgerow/fescue Fescue field
Biomass(mg/g)
Cropping System
PLFA Sub-categories at Bradford
Rhizobia
Arbuscular
Mycorrhizal
Saprophytes
Soybean-Conventional-had no Mycorrihizae or Rhizobia

82. Scientists describe 3 pools of soil organic matter
**really is a continuum of decomposition
Passive SOM
500 – 5000 yrs
C/N ratio 7 – 10
Active SOM
1 – 2 yrs
C/N ratio 15 – 30
Slow SOM
15 – 100 yrs
C/N ratio 10 – 25
•Recently deposited organic material
•Rapid decomposition
•10 – 20% of SOM
•Intermediate age organic material
•Slow decomposition
•10 – 20% of SOM
•Very stable organic
material
•Extremely slow
decomposition
•60 – 80% of SOM
82

83. Results are read in a spectrometer in lab or
field or from a color card
Potassium
Permanganate Test
KMnO4 oxidizes active carbon. The
purple color of the chemical
changes to pink the more active
carbon there is in a soil sample.

87. Table 3. PLFA concentrations
Treatment Total Gram+ Gram− Actino Fungi AM Fungi Protozoa
Bare 15.07 DE 4.45 CD 3.94 DE 2.17 BC 0.42 BC 0.58 DE 0.07 B
Black Poly 13.27 E 4.10 D 3.28 E 1.87 C 0.36 C 0.48 E 0.04 B
White Poly 15.49 CDE 4.61 BCD 4.04 DE 2.20 BC 0.45 BC 0.59 CDE 0.08 AB
Rye 19.33 AB 5.48 AB 5.58 AB 2.69 A 0.61 AB 0.85 A 0.18 AB
Rye Roots 18.39 ABC 5.26 ABC 5.16 ABC 2.53 AB 0.60 AB 0.73 ABC 0.14 AB
Rye Shoots 16.72 BCD 4.90 BCD 4.51 CD 2.41 AB 0.44 BC 0.66 BCD 0.11 AB
Vetch 20.38 A 5.82 A 5.76 A 2.71 A 0.73 A 0.81 AB 0.20 AB
Vetch Roots 19.04 AB 5.47 AB 5.36 ABC 2.59 AB 0.54 BC 0.72 ABCD 0.27 A
Vetch Shoots 17.39 BCD 5.05 BC 4.77 BCD 2.46 AB 0.55 ABC 0.71 ABCD 0.13 AB
 Plastic Has Much Less Than Cover Crops!!
Buyer, et al, 2010

89. Doug Peterson

90. 140°
F
130°
F
100°
F
70° F
Soil bacteria die
100% moisture lost through
evaporation & transpiration
15% moisture is used for growth
85% moisture lost through
evaporation & transpiration
100% moisture is used for growth
J.J. McEntre, USDA
SCS, Kerrville, TX, 1956

92. Surface crust impedes infiltration.
Open, granular surface structure
enhances infiltration.
Biopores (earthworm channel)
enhance infiltration.
Conventionally
tilled field
No-till field
92

93. From Steve Groff
Cover Crop No Cover Crop

94. No-Till With Cover Crop Took Several Hours For
Water To Run-Off

98.  Biggest challenge in No-Till Organic is
producing enough biomass to control weeds
 9,000 lbs is needed
 Sorghum X Sudan can reduce weeds
 harvest
 During transition three years of continuous
cover crops is desired.
 Can be harvested-for livestock and kill emerged
weeds

99.  Continuous cover
crops during can
increase soil active
carbon and soil health
leading to better
water infiltration

100.  Huge Kill-Off
 Often highest yield
following
 Take Advantage Of This
 Small Grain-Mow
afterward and plant
cover crops
 Suppress Volunteer
pasture grasses
 Cover Crop
 Summer

101.  Coming from a tilled
conventional grain field
 Were Weeds
Controlled?-cover crops
and no-till cash crops
 If not: Three year cover
crops
 -winter/summer
 Graze or hay?
 Need Cash?-plant small
grain and follow with
summer cover crop

102.  Cover Crops
 Use for weed
smothering with
transplants
 Direct Seeding-lightly
till
 Smother Crops
During Times of Non
Cash Crop
 Avoid Using Plastic
Mulch

103.  Lengthen Rotation-
including hay crops
 Early Maturing Cultivars
 Planting Later-Take
Advantage of Cover Crop
Biomass Production
 Grow Cover Crops Year
Around Including Those
That You Can Harvest For
Sale

104. Reinbottt@Missouri.edu
573-884-7945