Reviews our research results on controlling weeds with cover crop mulches rather than black plastic and discusses the details of incorporating them on the farm. (Farmers, market gardeners and ag professionals)

1. ©2010 Rodale Institute
Impacts of Plastic and Cover Crop
Mulches on Weeds, Soil Quality, Yields
and Season Length for Tomatoes

2. ©2010 Rodale Institute
Vegetable Research at Rodale
1980’s – Research on
amaranth, wild triga,
and many other
vegetable trials
1990’s-2000’s – Focus on
larger scale grain
production
2010’s – Renewed interest in
vegetable production
in balance with grain
crops

3. ©2010 Rodale Institute
Research Goals
• Maintain and improve yields
• Reduce or eliminate external inputs
• Manage weeds
• Reduce/redirect labor
• INCREASE SOIL HEALTH
Make farming more sustainable and profitable by
developing and improving organic practices that:
How?
• Cover crops
• Compost
• Rotation
• Reduce tillage

4. ©2010 Rodale Institute
What is Organic No-Till?
1.Grow a fall-planted winter annual
cover crop, such as rye or hairy
vetch
2.Let the cover crop grow in the
spring until it reaches at least
50% flowering (mid-late May for
rye, late-May or early-June for
vetch)
3.Kill the cover crop by rolling it
down with a front-mounted roller
and planting with a rear-mounted
no-till planter in one pass.
Three Basic Steps

5. ©2010 Rodale Institute
The No-Till Roller in Action
Rolling Rye Rolling Hairy Vetch

6. ©2010 Rodale Institute
A Brief History of Organic No-Till
1988 -1994 - First tried in the Low-Input Reduced Tillage
(LIRT) Trial
Late 1990s - Attempts to stalk-chop cover crops not very
successful
2002 - Roller designed and built by Jeff Moyer and
John Brubaker with NE SARE funding
Fall 2004 – Received NRCS Conservation Innovation
Grant for no-till received
Spring 2006 – Received SARE No-Till Grant
Fall 2008 – Received OREI IOP No-Till Grant, led by
Iowa State University
Spring 2011 – Received SARE No-Till Vegetable
Production Grant

7. ©2010 Rodale Institute
Benefits and Challenges of
Organic No-Till
• Reduces number of tractor passes over the field
(saves time, fuel, and money)
• Keeps the soil covered to reduce erosion and
weed growth at vulnerable times
• Retains moisture and cools soil in mid-summer
• Eliminates herbicide use
• Can keep soil too cool in the spring
• Can allow weed growth if the cover crop stand is
poor
• May provide habitat for plant-damaging pests
• Requires later planting, and well-timed rolling
Benefits
Challenges

8. ©2010 Rodale Institute
The importance of timing in
cover crop termination
Rye, rolled at the soft dough stage,
lays down well and dies quickly.
Vetch, when rolled before it reaches
at least 50% flowering, doesn’t die
and will continue to grow and
compete with the crop plants.

9. ©2010 Rodale Institute
Other cover crops that can be used…
Or any grain –
wheat, barley,
triticale, mature
oats, etc.
Fall-Planted Spring Oats
(die and lie down on
their own at frost)
Austrian Winter Peas
(flowers early)
Crimson Clover
(flowers early)

10. ©2010 Rodale Institute
Cast Iron Closing Wheels
Additional Weight
130 lb per row
Equipment modifications to make it work

11. ©2010 Rodale Institute
Ron Morse’s No-Till Vegetable Transplanter

12. ©2010 Rodale Institute
No-till pumpkins

13. ©2010 Rodale Institute
No-till peanuts

14. ©2010 Rodale Institute
No-till eggplant

15. ©2010 Rodale Institute
No-till tomatoes

16. ©2010 Rodale Institute
Cover Crop Mulches for Small-Scale Production?
Yes!!!
Cover crops can be
crimped by hand,
scythed or
mowed.
Timing is still key.
Kill is most successful
when the cover crop is at
bloom or anthesis, but
mowing can provide
greater flexibility.

17. ©2010 Rodale Institute
Rodale Institute’s Current Vegetable
Work
• Identify four effective cover crops/combinations for
weed suppression and N contribution in vegetable
production;
• Measure efficiency of cover crop termination
techniques, economic returns, and soil health
impacts;
Project goals:
Project title:
Reducing Plastic Mulch Use by Expanding Adoption
of Cover Crop-Based No-Till Systems for Vegetable
Producers

18. ©2010 Rodale Institute
Block 1 Block 2 Block 3 Block 4
111 35' Buffer 232 35' Buffer 321 35' Buffer 422
V 112 RV 231 R 322 R 421
113 233 323 423
133 221 313 432
RV 131 R 223 V 311 RV 433
132 222 312 431
121 213 331 412
R 123 V 212 RV 333 V 411
122 211 332 413
First Digit Second Digit Third Digit
1) 1st Replicate 1) Vetch 1) Black plastic
2) 2nd Replicate 2) Rye 2) Roll
3) 3rd Replicate 3) Rye + Vetch 3) Mow
4) 4th Replicate
Field 6 - 2012 SARE No Till Veggie Tomatoes
50'
10Cover
10'
30' 90'
The Basic Experimental Design…
3 cover crop mixtures
X 3 cover crop kill methods
9 treatments
X 4 replications
36 plots

19. ©2010 Rodale Institute
RI’s 2010 trial
3 cover crop treatments:
1. Vetch
2. Rye
3. Rye-vetch mix
3 termination methods:
1. Black plastic
2. Mowed
3. Rolled
3 tomato varieties:
1. Black Prince
2. Bellstar
3. Glacier
1 pole bean variety (KY Wonder)

20. ©2010 Rodale Institute
Changes to the RI Field for 2011
• No beans
• Only one variety of tomato (Glacier)
• One row per plot for all treatments
• Separate weeds only into perennial and annual categories
(not by species)
SIMPLIFY!
111
112
113
40'buffer
131
133
132
40'buffer
122
121
123
40'buffer
222
223
221
40'buffer
233
232
231
40'buffer
212
213
211
40'buffer
331
333
332
40'buffer
323
322
321
40'buffer
312
311
313
40'buffer
432
433
431
40'buffer
422
421
423
40'buffer
412
413
411
Vetch R + VVetch R + V Rye VetchR + VRye
Field 9/10 2011 No Till Veggie SARE Tomatoes
Rye Vetch
Block 1 Block 2 Block 3 Block 4
R + V Rye
50'
covercrop
planting
width
30'
170'
800'

21. ©2010 Rodale Institute
The 2011 Tomato Field Throughout the Year

22. ©2010 Rodale Institute
Cover Crop Biomass and N Content
2010 Cover Crop Biomass
0
2000
4000
6000
8000
10000
12000
14000
VETCH RYE RYE/VETCH
lb/ac
plastic rolled/mowed plastic rolled/mowed plastic rolled/mowed
0
2000
4000
6000
8000
10000
12000
14000
black plastic roll mow black plastic roll mow black plastic roll mow
lb/acredrymatter
May 13th
May 13th
May 13th
May 27th
June 10th June 10th
June 10th
June 10th
June 10th
VETCH ALONE RYE ALONE RYE/VETCH MIX
Nitrogen Content of Cover Crops at Termination
0
50
100
150
200
250
Black Plastic Roll Mow Black Plastic Roll Mow Black Plastic Roll Mow
CoverCropNitrogen(lb/ac)
VETCH ALONE RYE ALONE RYE/VETCH
2010 Cover Crop Nitrogen Content
0
50
100
150
200
250
VETCH RYE RYE/VETCH
lb/ac
plastic rolled/mowed plastic rolled/mowed plastic rolled/mowed
2010 2011
CovercropbiomassCovercropNcontent
14,00014,000
lb/acDryWeight
lb/acDryWeight
lb/ac
lb/ac
250250

23. ©2010 Rodale Institute
Weed Biomass at 4 and 8 Weeks
Weed Biomass at 8- 10 weeks
0
1000
2000
3000
4000
5000
6000
7000
8000
Black
Plastic
Rolled Mowed Black
Plastic
Rolled Mowed Black
Plastic
Rolled Mowed
Lbs/acredryweight
VETCH RYE RYE/VETCH
Weed Biomass at 4- 6 weeks
0
1000
2000
3000
4000
5000
6000
7000
8000
Black
Plastic
Rolled Mowed Black
Plastic
Rolled Mowed Black
Plastic
Rolled Mowed
Lbs/acredryweight
VETCH RYE RYE/VETCH
2010 8-Week Weed Biomass
0
1000
2000
3000
4000
5000
6000
7000
8000
VETCH RYE RYE/VETCH
lbs/acredryweight
plastic roll mow plastic roll mow plastic roll mow
2010 4-Week Weed Biomass
0
1000
2000
3000
4000
5000
6000
7000
8000
VETCH RYE RYE/VETCH
lb/acredryweight
plastic roll mow plastic roll mow plastic roll mow
2010 2011
4-6weeksafterplanting8-10weeksafterplanting
80008000
80008000
lb/acDryWeightlb/acDryWeight
lb/acDryWeightlb/acDryWeight

24. ©2010 Rodale Institute
Soil Moisture and Temperature
2011 Soil Moisture Through The Season
0
5
10
15
20
25
30
35
June 14th July 18th Aug 17th Sept 14th
%moisture
black plastic
roll
mow
black plastic
roll
mow
black plastic
roll
mow
2010 Soil Moisture Through the Season
0
5
10
15
20
25
30
35
May 7th June 1st June 24th July 20th
%moisture
vetch plastic
vetch rolled
vetch mowed
rye plastic
rye rolled
rye mowed
rye/vetch plastic
rye/vetch rolled
rye/vetch mowed
2010 Average and Maximum Soil Temperature by Treatment
0
5
10
15
20
25
30
35
plastic roll mow plastic roll mow plastic roll mow
temperature(C)
vetch rye rye/vetch
2011 Average and Maximum Soil Temperature By Treatment
0
5
10
15
20
25
30
35
plastic roll mow plastic roll mow plastic roll mow
temperature(C)
vetch rye rye/vetch
2010 2011
SoilMoisturebyDateAvgandMaxTemperature
35
%moisture%moisture
%moisture
%moisture
35
3535
May June July August June July August September

25. ©2010 Rodale Institute
2011 Tomato Yields (total and marketable)
total yield = darker bar (left)
marketable yield = lighter bar (right)
0
20,000
40,000
60,000
80,000
100,000
120,000
Black Plastic Rolled Mowed Black Plastic Rolled Mowed Black Plastic Rolled Mowed
lbs/acrefreshweight
e
E
b
B
b
B
de
DE
ab
AB a
A
e
E
cd
CD
c
C
VETCH RYE RYE/VETCH
~ 6500 lbs of tomatoes harvested
from late August to mid October
2010 Tomato Yields
0
20,000
40,000
60,000
80,000
100,000
120,000
VETCH RYE RYE/VETCH
lb/acre
plastic roll mow plastic roll mow plastic roll mow
~ 4000 lbs of tomatoes harvested
from late July to early October
2010 2011
120,000120,000
lbs/acfreshweight
lbs/acfreshweight

26. ©2010 Rodale Institute
Comparison of Outcomes from 2010 to 2011
• Rolled Vetch was weediest
(replanted=not enough
biomass?).
• Mowed Rye/Vetch had the
fewest weeds, compared to
black plastic.
• Rye and Rye/Vetch kept weed
biomass under 1500 kg/ha.
• Rolled and Mowed Rye and
Rye/Vetch were comparable to
Black Plastic treatment in
yields.
• Most rolled and mowed cover
crops were equally weedy at
10 weeks
• Rolled Rye/Vetch had the
fewest weeds, compared to
black plastic.
• All non-plastic treatments had
weed biomass over 3000
lbs/ac (up to 6000 lb/ac).
• Black Plastic out-yielded all the
other treatments.
• Rolled and Mowed Rye/Vetch
out-yielded the Vetch and the
Rye, and both termination
techniques yielded equally.
2010 2011
This is why we do multi-year agricultural research projects!

27. ©2010 Rodale Institute
Spring 2012 Cover Crop Biomass
0
2,000
4,000
6,000
8,000
10,000
12,000
14,000
plastic roll mow plastic roll mow plastic roll mow
Vetch Vetch Vetch Rye Rye Rye Rye/Vetch Rye/Vetch Rye/Vetch
kg/ha
14,000
kg/ha

28. ©2010 Rodale Institute
We also performed research at
four collaborating farms in 2011
The Farmer Team:
Mike Baki – Genesis Farm CSA, Blairstown, NJ
James Weaver – Meadow View Farm, Bowers, PA
John & Aimee Good – Quiet Creek Farm CSA, Kutztown,
PA
Elizabeth & Douglas Randolph – Swallow Hill Farm,
Cochranville, PA
Doug Randolph
planting his cover crops

29. ©2010 Rodale Institute
Plot Lay-Out at Each Collaborating Farm
roll std. roll std roll std
*
*
11 12 21 22 31 32
*
*
Row 1 Row 2 Row 3 Row 4 Row 5 Row 6 ^Corner of field
3 ft 5 ft 5 ft 3 ft 5 ft 5 ft 3ft 5 ft 5 ft
roll: rolled cover crop, rye 70#/A and vetch 25#/A.
std: standard practice - spaded cover crop with BioTelo biodegradable plastic mulch
1st Digit: Block
2nd Digit:Practice (1= roll, 2=std practice)
39 Feet wide
GrassBufferRoad
Grass Buffer Road
100ftlong
Block 3
3 Markers
installed
here at
~66 ft
3 Markers
installed
here at
~33 ft
Baki 2010 Tomatoes
Block 1 Block 2
std. roll roll std std. roll
12 11 21 22 32 31
Row 1 Row 2 Row 3 Row 4 Row 5 Row 6
roll: rolled cover crop, rye 70#/A and vetch 25#/A.
std: standard practice
1st Digit: Block
2nd Digit:Practice (1= roll, 2=std practice)
Goods 2010 Tomatoes (or squash?)
Block 1 Block 2 Block 3
Baki
Good
Weaver
Randolph
Tomatoes, Melons, and
Summer Squash
Tomatoes and Cabbage,
using a raised bed roller
Acorn Squash Acorn Squash
10 ft. {
R 1
roll
11
R 12
R 2
std Clover
12 Rye
R 11
R 3
roll
21
R 10
R 4
std Clover
22 Rye
R 9
R 5
std Clover
32 Rye
R 8
R 6
roll
31
R 7
} 10 ft.
roll: rolled cover crop, rye 100#/A and clover 25#/A.
std: standard practice - pre-emergence burn down
Orange flag
Yellow flag
Yellow flag
350
feet
55
feet
Orange flag
Orange flag
Road
32 feet
Yellow flag
std. roll std. roll 9' std. roll std. roll
63'
G # G # G # G # G # G # G # G #
South
100'
North
12 11 22 21 32 31 42 41
G # G # G # G # G # G # G # G #
Row 1 Row 2 Row 3 Row 4 Row 5 Row 6 Row 7 Row 8
10' 10' 10' 10' 7' 10' 10' 10' 10'
33'
Yellowflag
Yellowflag
Weaver 2012 Cabbage Weaver 2012 Tomatoes
Yellowflag
Yellowflag
Block 1 Block 2 Block 4
powerlinerow
Blueflag
Blueflag
Blueflag
Drivelane
Blueflag
Block 3

30. ©2010 Rodale Institute
The Raised Bed Roller

31. ©2010 Rodale Institute
What we’ve learned
from the farmers’ fields….

32. ©2010 Rodale Institute
Spring Cover Crop Biomass
Spring Cover Crop Biomass
0
2000
4000
6000
8000
10000
12000
14000
Plastic Rolled Plowed Rolled Rolled and
Herbicide
Rolled Black Plastic Rolled
biomass(lb/ac)
May 6
tb
June 2
nd
May 10
tb
May 26
tb
May 23
tb
May 23
tb
May 25
tb
June 1
tb
Baki WeaverRandolphGood
rye/clover
Nothing here

33. ©2010 Rodale Institute
Nitrogen Inputs from the Cover Crops
Nitrogen Inputs from Cover Crops
0
50
100
150
200
250
Black plastic Rolled Plowed Rolled Rolled and
herbicided
Rolled Black plastic Rolled
lbs/ac
May 6th
June 2nd
May 10th
May 26th
May 23rd
May 23rd
May 25th
June 1st
Baki Good Randolph Weaver
nothing
Spring Cover Crop Biomass
0
2000
4000
6000
8000
10000
12000
14000
Plastic Rolled Plowed Rolled Rolled and
Herbicide
Rolled Black Plastic Rolled
biomass(lb/ac)
May 6
tb
June 2
nd
May 10
tb
May 26
tb
May 23
tb
May 23
tb
May 25
tb
June 1
tb
Baki WeaverRandolphGood
rye/clover

34. ©2010 Rodale Institute
Carbon Inputs from the Cover Crops
Cover Crop Carbon Inputs
0
1000
2000
3000
4000
5000
6000
Black plastic Rolled Plowed Rolled Rolled and
herbicided
Rolled Black plastic Rolled
lbs/ac
Baki Good Randolph Weaver
May 6th
June 2nd
May 10th
May 26th May 23rd
May 23rd
May 25th
June 1st
nothing
Spring Cover Crop Biomass
0
2000
4000
6000
8000
10000
12000
14000
Plastic Rolled Plowed Rolled Rolled and
Herbicide
Rolled Black Plastic Rolled
biomass(lb/ac)
May 6
tb
June 2
nd
May 10
tb
May 26tb
May 23
tb
May 23
tb
May 25
tb
June 1
tb
Baki WeaverRandolphGood
rye/clover

35. ©2010 Rodale Institute
Weed Biomass at 4 and 8 Weeks
SARE Veggie collaborating farmers 4- 6 week weed biomass
0
1000
2000
3000
4000
5000
6000
7000
Plastic Rolled Plowed Rolled Rolled and
Herbicide
Rolled Black Plastic Rolled
biomass(kg/ha)
Baki
July 20
th
July 19
th
July 28
th
July 28
th
WeaverRandolphGood
On-Farm 8- 10 Week Weed Biomass
0
1000
2000
3000
4000
5000
6000
7000
Plastic Rolled Plowed Rolled Rolled and
Herbicide
Rolled Black Plastic Rolled
biomass(kg/ha)
Baki
Aug 17
th
Aug 16
th
Aug 29
th
Aug 29
th
(tom) Sept
14
th
(cab)
WeaverRandolphGood
Weeds at 4-6 Weeks
Weeds at 8-10 Weeks
Spring Cover Crop Biomass
0
2000
4000
6000
8000
10000
12000
14000
Plastic Rolled Plowed Rolled Rolled and
Herbicide
Rolled Black Plastic Rolled
biomass(lb/ac)
May 6
tb
June 2
nd
May 10
tb
May 26
tb
May 23
tb
May 23
tb
May 25
tb
June 1
tb
Baki WeaverRandolphGood
rye/clover

36. ©2010 Rodale Institute
Yields
0
5,000
10,000
15,000
20,000
25,000
30,000
35,000
40,000
45,000
Plastic Rolled Plowed Rolled Rolled and
Herbicide
Rolled Black Plastic Rolled
yieldlb/ac
RandolphGoodBaki Weaver
tomatoes
squash squash
tomatoes

37. ©2010 Rodale Institute
How do we explain these results?
• Wet spring led to low vetch
biomass and N input?
• Gaps in cover rolled with the
raised bed roller?
• Thistle in one rolled plot at
the Randolph’s?
• NO WEEDING?
Stay tuned for answers in
the 2012 growing season!

38. ©2010 Rodale Institute
Changes for 2012
LET THEM WEED!!!
• Collaborating farmers will be
allowed to weed after the 4-
6 week weed biomass cut
• The farmers will track the
equipment and amount of
time spent weeding, to
include in the economic
analysis
• RI-site plots will also be
weeded after the 4-week
biomass cut, tracking labor

39. ©2010 Rodale Institute
Stay tuned for project updates…
Christine Ziegler
christine.ziegler@rodaleinstitute.org
(610) 683-1415
www.rodaleinstitute.org
Thank you!