 |
| Broader
roller use
raises new questions
Having no-till roller research in seven places
under many situations helps to surface the challenges
to having it work effectively over a range of
conditions. Here are some of the emerging questions.
What should farmers do:
• When they can’t get
their cover crop sown in time in the fall?
• When the timely planted cover crop yields
a marginal stand?
• To figure out the critical decision dates
for switching to Plan B for each phase of the
system?
• When they realize they can’t get
their cover crop rolled in timely fashion?
• When they’ve rolled their cover,
but missed their late planting date for their
cash crop?
• When they are planting in a second pass
and can’t see where their planter has already
planted?
• When they’ve planted as they’ve
rolled, but the cover is not dying?
• When their planned herbicide backup is
not effective?
Also:
• Should growers new to this
system start with shorter-season varieties to
allow for replanting as a contingency?
• How can growers learn techniques to improve
planter function in heavy residue, and how can
they know when they need to go to extraordinary
measures to assure proper seed placement?
• Does this system work with a winter legume
to supply needed N in areas where summers are
typically dry?
We have next summer to start answering these
questions where the rollers are operating. It’s
likely that meaningful recommendations for a promising
tool so tied to the success of two crops in sequence
will require several years of experience to develop. |
|
Posted December 14, 2006: Any experimental
technology in farming takes time to refine and to be adapted
to specific applications. This is holding true in this year’s
trials for the no-till roller-crimper developed by The Rodale
Institute.
Researcher/farmer cooperating teams across the country outlined
some successes, some challenges and a continuing learning
process in the first phase of the USDA-NRCS No-Till Plus project.
Reports included data on cover crop establishment in the fall
of 2005 and this year’s cover crop termination, cash
crop establishment and weed management. Harvest and yield
data is speculative from most sites until the next reports
come in.
Timing is a critical issue when rolling down cover crops.
It’s likely that several cooperators had less-than adequate
kills due to rolling too early, before cover crops were fully
mature and most vulnerable to being killed by rolling. Seeder
setting and modification to cover crop mat thickness and soil
type is another important variable with a learning curve attached.
Drought became a major factor in several areas. And there’s
room to improve communication between farmers and researchers
to synchronize data collection with necessary field work.
Each collaborator received a roller/crimper and front-mounted
hitch for the tractor of their choice. Several rollers were
delivered late due to manufacturing problems, and some of
the front hitches were delivered too late to use for the season.
In spite of these challenges, every site managed to get their
plots established by rolling cover crops and planting no-till
into them.
While each site had varying degrees of success, we learned
a lot in this first cropping year about the no-till roller’s
application across a range of geographical settings and about
each of the cover-crop/main-crop interactions.
Here at The Rodale Institute’s field site, we experienced
our best season ever as we continue to refine our roller operations
in response to timing as well as planter setup. The combination
of reasonably good weather and our cumulative experience (with
using the roller and setting up its complementary no-till
planter to get solid seed placement) proved successful.
We know there’s no substitute for this kind of experience,
which means learning, observing and fixing what needs fixed.
Our direct interaction with the growers has enhanced their
ability to adopt this technology to their situations.
As a group, we learned as much about what doesn’t work
as about what does. Click the regions below for more detail
about how the No-Till Plus Project went for the collaborators
in 2006.
| SOUTHEAST
|
|
|
|
Georgia
Mark
Vickers, farmer
Lackluster results with roller/crimper
could have resulted from erratic irrigation.
Mark Vickers is a seasoned no till farmer who has been
utilizing cover crops since the early ’90s. He has
successfully modified his planting from conventional methods
to planting in heavy cover crop residue, an evolution that
took him almost a decade to perfect. Vickers has come to
realize that heavy residue, laid down flat in a uniform
direction, enhances this new production system in the Southeast
and make it easier for new growers to successfully transition
to a new way of doing things. For five years prior to entering
this project, Vickers has used a large pipe suspended approximately
2 inches off the ground under the belly of his tractor for
rolling down his cover crop (1-2 bushel/acre of rye).
Following cotton harvest, a 1-acre test plot was planted
in rye (Wrens Abruzzi) in December 2005 at a rate of 1 bushel/acre
of farm-saved seed. Vickers sprayed 2,4-D (1 pint/acre)
at 15-20 gallons/acre (at a pressure of 20-25 psi) for scattered
winter weed population of less than 1.5 plants per square
foot. These weeds consisted of primrose, wild radish and
other minor winter weeds.
Rye matured on May 19 (not harvested) and was rolled-down
according to the grower’s standard practice and also
using the Rodale roller. The peanut crop was planted on
May 20 (110 pounds of seed/acre, 2-inch deep, soil temperature
of 65°F 68°F). Soil moisture was becoming limited.
No fertilizer or chicken litter was applied to the cover
crop (1,200-1,500 pounds [0.6 to 0.75 T/A] estimated dry
matter/acre).
No pre-plant insecticide or herbicide was used at planting.
On June 22, Vickers became concerned with a scattered population
of morning glory, pigweed and grasses (Texas millet, patch
of Common Bermuda grass escapes) and because peanut were
not lapping due to extended drought. A spray of Storm and
Select (post-emergent herbicides) at standard rate was applied
in 20-25 gallons water/acre at 30-40 psi.
The seeding rate—110 pounds of Georgia Green peanuts—was
constant across both plots. At planting, 1 quart of Prowl,
Strongarm (medium rate), Valor at 2 ounces and 5 pounds/acre
of Thimet were used in the standard plot only. Burn down
was accomplished on both plots on June 18 with1.5 pints
of Storm; 1 pint 2,4/D was also applied on this date.
As well, the standard and test plots both received same
following treatments: Five applications of the fungicicde
chlorothalonil at 1.5 pints were made starting approximately
on July 10 (at first bloom). Boron at 1 quart per application
was sprayed twice. On September 15, 2 ounces of Karate was
applied for velvet bean caterpillar control. Spot treatments
was made for grass control in the end of August.
During the peanut growing season, fields received 5.8 inches
of rainfall and eight applications of irrigation at 1 inch
per application. This was a historically dry season, with
yields better than we expected under challenging conditions.
The peanut field was scouted weekly for pests, with pictures
taken and field notes made weekly.
The yield in the standard plot was 4,311 pounds compared
to 3,003 in the test plot. The test plot received no Prowl,
Strongarm, Valor or Thimet. All other production practices
were same. Weed control and early insect control was similar
in the test field of rye rolled-down with Rodale roller
as compared to the farmer’s standard practice.
The test plot was located at the end of the pivot where
water distribution is characteristically uneven, particularly
with heavy summer winds. This could have contributed to
the lower yield in the test plot.
Virginia (southern)
Ron
Morse, collaborator
Variable kill on covers, planting
time issues, more biomass controls more weeds.
Cover crops were seeded in fall 2005 with biomass samples
taken in April 2006. With the exception of oats, growth
and final yield (biomass) of all cover crops tested were
less for late seeding (November 10).
The Rodale Institute roller-crimper arrived in April, but
the front mount didn’t arrive until after cover crops
were roll-crimped. In a work-around, cooperating farmer
Paul Davis constructed an up-front tractor mount, which
worked relatively well.
Full-season soybean was seeded May 6, and cover crops were
roll-crimped in one pass. Although the farmer-built roller-crimper
appeared to function properly, the percentage kill varied
considerably as follows: barley (80 percent), rye (70 percent),
oats (40 percent) and hairy vetch (20 percent).
Pumpkins were direct seeded June 19 into cover crop residues
that were roll-crimped on May 7. This two-pass system was
required because maturity of the cover crops occurred four
to six weeks before pumpkin seeding.
Weed growth was moderate to high in all no-herbicide-treated
plots. Weed pressures were worse with pumpkin than soybean
because of the delayed planting with pumpkins. Overall,
weed suppression was better with rye and rye/hairy vetch
than with barley, oats and crimson clover. Weed suppression
was highly correlated with cover crop biomass (Table 1).
The greater the quantity and persistence of the cover crop
mulch (e.g., rye), the better was the weed suppression in
the no-herbicide-treated plots.
| Cover
crop planted |
Early
seeding (9/30) |
|
Mid
seeding (10/20) |
|
Late
seeding (11/10) |
|
| Crimson clover |
1.46 |
|
1.63 |
|
NA |
| Barley |
2.08 |
|
1.35 |
|
1.23 |
| Oats |
2.09 |
|
1.45 |
|
1.85 |
| Rye |
4.21 |
|
3.59 |
|
1.34 |
| Hairy vetch |
2.84 |
|
2.04 |
|
1.64 |
| Rye & Hairy vetch |
3.31 |
|
3.70 |
|
2.42 |
Average |
2.67 |
|
2.29 |
|
1.70 |
Preliminary conclusions:
- The Rodale Institute roller-crimper appeared to function
well; however, the thicker and taller the cover crops,
the better was the percentage kill by the roller-crimper.
Thus, high-biomass, dense residues are highly recommended.
- In situations where herbicides are not used (e.g. organic
farming), using the roller-crimper on high-biomass cover
crops (e.g., rye and rye/hairy vetch) could be a valuable
tool to improve percentage kill, weed suppression and
effectiveness of direct seeding.
- One-pass systems appear to be ideal when seeding large-seeded
crops such as soybean in which seed germination and stand
establishment are not severely affected by allelochemicals,
pathogens and/or insect pests associated with the high-biomass,
green-residue (same-day killed) cover crops.
| MIDWEST |
|
|
|
Iowa
Kathleen
Delate, collaborator
Covers grew but did not die upon
being rolled; drought daunted beans.
At the Neely-Kinyon Research and Demonstration Farm in
Greenfield, Iowa, two treatments were planted, one consisting
of a mix of winter wheat and winter pea, the other consisting
of a mix of winter rye and hairy vetch. Both treatments
were planted on September 12, 2005; the wheat and pea mix
at 75 pounds/acre, and the rye and vetch mix at 96 pounds/acre
(64 pounds/acre of the rye and 32 pound/acre of the vetch).
As of October 13 (31 days after planting), the legumes in
each treatment had an average of three inches of growth
above ground. The cover crops were planted for three no-till
crops: corn, soybeans and tomatoes.
At the Rosmann Family Farm in Westphalia, Iowa (near Harlan
in Southwest Iowa), the same treatments were planted on
September 19, 2005, at 94 pounds/acre for the wheat and
pea mix and 100 pounds/acre for the rye and vetch mix (at
60 pounds/acre and 40 pounds/acre, respectively).
There was a good stand of cover crops at both sites. Rolling
and no-till drilling took place May 29 at the N-K Farm and
June 2-3 on the Rosmann Farm. The rolling was conducted
when small grains in the cover crops were in the dough stage—headed
out but not fully developed, per instructions. The cover
crop crushed down well enough but then proceeded to come
back up into place, thus negating a "crushed"
cover into which the corn and soybeans would be planted.
The most unfortunate event that followed, however, was the
lack of rain through June and July. The cover crop continued
to grow, but the corn and soybeans did not. (The crop is
not yet harvested, but the predicted yields are 15 bu/acre
for soybeans and 80 bu/acre for corn.)
In order to salvage this experiment, irrigation was purchased
for the no-till tomatoes and used when necessary. Roma tomato
seedlings were planted on June 15 and compared with a conventional
tilled plot. Harvests were heavy: five for each group. Data
has not yet been analyzed but predictions are for excellent
yields in all treatments. The hairy vetch continued to grow
extensively in that treatment and was thus weeded and removed
form the plots June 27.
An updated report will be filed when all crops are combined
and yields analyzed. A field day was held August 23, where
over 225 attendees viewed the organic no-till plots and
discussed the project with cooperator.
Michigan
Dale
Mutch, collaborator
“Excess biomass” leads
to replanting of soybeans, but results were good
Michigan State University Extension’s Covercrop/IPM
Program has been developing an organic no-till soybean system
for several years. Here are the results from 2006, utilizing
The Rodale Institute’s no-till roller/crimper.
Vetch and rye-vetch were drilled August 24, 2005. Due to
drought in 2005, we irrigated about two inches of water
on these treatments to stimulate germination. Rye was drilled
Sept. 15 at a rate of 2.5 bushels/acre. Vetch was drilled
at a rate of 30 pounds/acre. The rye-vetch was drilled at
2 bushels/acre and 25 pounds/acre, respectively. Weed-free
controls were drilled to rye at 2 bushels/acre (Table 2).
The first crimping treatment was on vetch alone on May
25, 2006. Treatments 2, 4, 5, 8 and 9 were all crimped on
June 2 (Table 2). Treatments 1 and 7 were crimped on June
5. Treatments 2, 4, 5, 8 and 9 were crimped a second time
and soybeans drilled at 150,000 seeds/acre on June 5. Treatment
3 had soybeans drilled into standing rye and then crimped/rolled
on June 5. Treatments 10 and 11 were controls where the
rye was flail mowed on May 25, the stubble rotor-tilled
on June 2 and soybeans drilled at 180,000 seeds/acre (Table
2). Soybeans were drilled rather than row planted because
there were very few, if any, weed seedlings in these plots.
Due to heavy mulch and poor seed-to-soil contact, Treatments
2, 3, 5, 6, 8 and 9 were replanted on June 15, 2006.
Biomass was sampled from these treatments. When rye was
drilled, yields averaged 5,262 pounds/acre and vetch averaged
4,573 pounds/acre. Rye-vetch averaged 6,345 pounds/acre
(Table 3).
The 2006 growing season has been excellent here at the
Kellogg Biological Station. We are extremely pleased with
the weed control and soybean growth in our no-till organic
soybeans. Replanting soybeans into the existing soybean
stand increased soybean populations. Additionally, replanting
reduced weed populations in the vetch cover crops. Cereal
rye appears to be the cover crop of choice. We have better
weed control and soybean stands drilling into rye. Vetch
is harder to kill with the crimper/roller system than rye.
The combination of rye-vetch resulted in too much mulch/residue
and made it difficult to drill soybeans into it.
Plans: Next season we are planning to
evaluate two rye varieties and barley. We will not be rolling/crimping
vetch.
| SOUTH |
|
|
|
Mississippi
Seth
Dabney, collaborator
Hurricane, poor cover crop stands,
planting issues, drought make it a tough year.
Cover crops of balansa clover and rye were broadcast near
the beginning of October 2005, after the soil had dried
sufficiently following Hurricane Rita (September 24, 2005).
No appreciable rain fell again until mid-November. This
resulted in thin cover crop stands, particularly of balansa
clover.
The decision was made to treat the four clover plots as
if they were fallow plots that differed from conventional
no-till in that they were flat rather than having hipped
rows. Plots are about 1000 feet long and about 25 feet wide,
a little more than 1/2-acre each.
Fertilizer (150 pounds 0-0-60) was broadcast applied in
March over the entire area based on soil test results. The
conventional no-till plots (no cover crop, hipped rows)
were chemically burned down on April 13. The balansa clover
plots were sprayed the same day. Cover crop biomass and
weed ratings were made on May 5.
When the roller and hitch finally arrived and were mounted,
the cover crop was rolled twice in the same direction on
May 15. Cotton (DP&L 445B BTRR cotton at 42,000 seeds/acre
in 38-inch rows) was planted the same day in a separate
pass with an 8-row planter traveling in the same direction
as the roller.
Herbicide treatments were applied to all plots May 16,
including the rye plots.
Fertilizer N was applied to all plots at 120 pounds N/acre
on May 25, 2006. Insecticide and herbicides were applied,
and the cotton was furrow irrigated according to the farmer’s
judgment during the balance of the season.
Cotton stand and weed data were collected May 26, June
11, June 26, July 21 and September 22. Pitted morning glory
in the rye plots had already flowered by May and was the
reason the farmer chose to spray the cover crop plots. Spiny
amaranth was the worst weed late in the season (only in
the rye) and was enough of a problem that it is expected
to increase weed pressure in the rye plots next year.
Balansa clover and rye were broadcast again for next year’s
trials, and the cotton was defoliated September 27.
Generally, the rye cover crop plots were much poorer than
the non-cover crop areas. The stands were sparser, the plants
were smaller and grew more slowly, the weed control was
worse, and the yields will no doubt be less than 50 percent
of the conventional no-till plots. This is due to several
factors, some of which were due to less-than-optimal management.
These include:
- The delay in obtaining the roller’s front-mount
hitch meant that the rye had nearly matured by the time
the cover crop was rolled. The soil was dried out, and
all available soil N was tied up in the rye.
- The planter settings resulted in the cotton seed being
too shallow in the rye plots. The lack of hipped rows
and the presence of cover crop mulch required that the
planter be adjusted for deeper planting, and perhaps that
the coulter be used, but this was not done.
- The moderate rather than dense cover crop stand did
not completely shade out the weeds, however the mulch
did prevent the applied herbicides (cotoran and staple
LX in a band, Sequence and Class Act in the middles) from
reaching the soil surface and so decreased their effectiveness.
- The farmer commented that he would not have been able
to tell where he had planted into the rye since there
were no beds to guide and his row marker didn’t
make a visible mark. This would limit the adoption of
the technology on a larger scale unless the planter was
equipped with a GPS guidance system.
- The flat-planted balansa clover areas did not have the
problems that the flat rye areas did and are expected
to yield similarly to the hipped row areas.
In summary, this was a difficult year for the cover crop
roller project in Mississippi.
| NORTHERN
PLAINS |
|
|
|
North Dakota
Steve
Zwinger, collaborator
Dought, extreme heat, poor cover
crop stands: plots abandoned.
Activities during this reporting period were mainly related
to the field work of establishing the cover crops, cover
crop termination and sowing the cash crop.
One of the cover crop treatments—dormant-seeded (sown
in late fall to germinate in spring) oats was not completed
since the window in North Dakota to dormant seed is short
and the weather conditions did not allow adequate time in
the spring to complete with the conditions changing from
frozen soils to tillable soils quickly. The cover crop treatments
then were fall sown rye, spring sown oats and barley, and
a bare check.
The 10-foot roller arrived at the Blaine Schmaltz farm
sometime in April; the three-point hitch to hook the roller
in front of the tractor did not come in the shipment. With
the lack of the proper parts to prepare the implement for
later use and spring fast approaching, the focus went into
spring planting.
The winter rye, despite the lack of snow cover, came through
the winter fine with no winter kill. As the cover crop came
out of dormancy it was met with very warm, dry conditions.
The droughty conditions lead to a reduced amount of plant
tillers which caused an overall reduction in plant biomass.
Based off of biomass data from the North Dakota State University
Research Extension Center, winter rye biomass (forage yields)
in 2006 was reduced by as much as 60 percent from previous
years.
The cover crop plot site was soil sampled May 10 to a depth
of 24 inches. A complete soil analysis will be run on the
soil gathered. Subsoil moisture was estimated to be below
normal, especially for this time of the year. Soil moisture
levels were at or below 50 percent of field capacity.
The spring cover crops were then sown May 10. The growth
stage of the winter rye at this time was the 4-5 leaf stage.
‘Ebeltoft’ spring oats was sown at a rate of
2 bushels/acre, while ‘Lacey’ spring barley
was sown at a rate of 2-1/4 bushels/acre in narrow (7-inch)
rows. Both spring-sown treatments and the bare check were
harrowed prior to planting. No herbicides were used for
weed control in the rye as Blaine is a certified organic
farmer.
Fall cover crop termination was completed on May 26 with
the use of the cover crop roller/crimper. The roller was
attached to the rear three-point hitch with the tractor
driven in reverse to have the roller operate in the proper
direction. In dealing with relatively small plots this worked
satisfactory to establish the plots for sowing. The front-mounted
three-point hitch had still not arrived to hook the roller
on the front of the tractor. Biomass samples were not taken
due to miscommunication between the researcher and the farmer.
The cover crop had been terminated before biomass data could
be collected.
Estimated biomass yields were 2,000 pounds dry matter for
the winter rye and less then 300 pounds dry matter for oats
and barley. With the hard, dry soil conditions a number
of trips across the rye were required to terminate the crop.
The short plants of oats and barley terminated easily, although
with the low amount of biomass there was very little cover
remaining. It seemed the roller firmed the ground after
its use, particularly in the no-till plots.
The plots were sown to “Maverick” pinto beans
June 5 at a rate of 90,000 PLS/acre. A John Deere no-till
drill (15-inch rows) was rented to complete this part of
the project. Plant stands were best (thickest) in the bare
plots while the rye plots had the lowest plant densities.
Pinto bean stands in the oat and barley plots were intermediate
to the bare and rye plots.
Growth of the pinto beans was very slow with the drought
conditions the area was faced. Temperatures during the later
part of June through August were among the highest ever
recorded in North Dakota. The only year that was comparable
in terms of above-normal temperatures was the summer of
1936, which was during the “dust bowl” years
of the “dirty Thirties.” Precipitation data
from the Rugby area for 2006 shows that rainfall for the
months of April through July was only 40 percent of long-term
normal.
Poor pinto beans growth made them uncompetitive with weeds.
Weeds were growing at a faster rate then the pinto beans,
requiring the farmer to clip the plots a number of times
to prevent the weeds from going to seed. Since Blaine is
a seed grower, he is very concerned about his weed-seed
bank and it is very important for him to keep his land free
from weeds. In terms of cover crop effect on weed growth,
the rye plots were the cleanest followed by the bare plots,
with oats and barley being the weediest.
Due to the drought and weeds, it was decided to abandon
the trial on August 15. Competition from weeds and the lack
of rain left the dry bean plants with essentially no pods
and no yield. The plot area was then worked up on August
16.
| WEST
COAST |
|
|
|
California
Jeff
Mitchell, researcher
Good cover crops, poor cash crops
in very dry conditions.
Our participation in the Rodale Institute’s No-Till
Plus Project in 2006 consisted of evaluations of the 15-foot
cover crop roller in conjunction with no-till cotton planting
and no-till transplanted eggplant and tomatoes.
Trial locations:
- The eggplant evaluation was conducted at the organic
farm of Tom and Denesse Willey in Madera, California.
- The tomato demonstration was implemented at Full Belly
Farm, an organic farm in Capay, California, with Paul
Muller and Andrew Brait.
- The no-till cotton study was conducted with Anil Shrestha,
PhD, University of California Integrated Pest Management
Program weed ecologist at the University of California
West Side Research and Extension Center in Five Points,
California.
While a variety of difficulties were encountered during
this first year at each of these sites, this project provided
considerable learning opportunities for all participants,
and we will use the experiences we have gained in 2006 to
better plan and conduct work in 2007.
In this first year, we evaluated various mixtures of Merced
rye, Trios triticale, Abruzzi rye, Austrian winter pea and
balansa clover at each site. These cover crop mixes were
planted in flat strips ahead of cotton in Five Points and
eggplant in Madera, but onto raised 60-inch beds preceding
tomatoes in Capay. Good cover crop stands and winter growth
were observed at all sites.
After taking cover crop biomass and height samples, we
rolled each cover crop at what we estimated to be an optimal
time in early April in Five Points and Madera, and in May
at the Capay field. These rolling times corresponded to
crop growth stages after flowering, but before viable seed
had been set. Rolling of the cover crops was done using
a front-mounted hitch in Five Points and Madera, and by
pulling the roller behind a tractor in Capay.
We rolled and planted in separate steps. The cover crops
did not die immediately at any of the sites and took roughly
three weeks to become completely dry and dead. Eggplant
and tomatoes were hand-transplanted in the surface cover
crop mulch three weeks after rolling, and cotton was no-till
seeded following the front-mounted roller with a John Deere
1730 six-row planter.
None of the 2006 summer crops grew well in the rolled cover
crops. In Five Points, the cotton stand was less than 10
percent of the traditional tillage crop stand in adjacent
plots due to the fact that the cover crop used surface soil
water and dried out the surface zone for the cotton seedlings.
There were not enough plants to conduct a useful machine
harvest in the cover crop plots for cotton yield determinations.
Yield data and observations are currently being discussed
for the eggplant and tomato fields, but they were also severely
reduced relative to the farmers’ expectations for
standard till crops in these fields.
We also determined weed densities and species at the Five
Points and Madera sites. In Five Points, there appeared
to be more fleabane and mare’s tail in the no-till
rolled cover crop plots relative to the standard-till plots,
but there also were fewer weeds such as lambsquarter and
pigweed, which are common in traditional till systems in
this region.
The following findings or lessons emerge from our
2006 experiences:
- Better timing of the cover crop rolling is needed to
achieve quicker kill.
- No-till planting worked in the rolled cover crops.
- Assuring adequate soil moisture for no-till cotton germination
and emergence is critical.
- Early season crop growth and vigor need to be improved
in the rolled cover crop systems.
- Possible differences and problems in fertility and soil
compaction need to be addressed in the no-till rolled
cover crop systems.
We’re having talks with each project participant
during the coming month to determine ways to improve our
approaches in 2007.
| MID-ATLANTIC |
|
|
|
Pennsylvania
(north-central)
Bill
Curran, advisor
Roller complements herbicide for
best results.
Over the past two seasons, most of the efforts at Pennsylvania
State University have focused on cereal rye (Secale
cereale) control as influenced by planting date in
the fall and termination date in the spring. The experiment
was repeated in 2006 and although the analysis is not yet
complete, it appears that our results are very similar for
the two years.
In 2005, cereal rye was successfully controlled with the
roller/crimper at about 50-percent flowering or growth stage
55 on the Zadoks scale. Rolling prior to this growth stage
was less effective at killing the cover crop. In 2006, additional
trials examined reduced rates of herbicide in combination
with the roller/crimper for control of both cereal rye and
hairy vetch (Vicia villosa). Glyphosate was examined
in cereal rye and 2,4-D was used in the hairy vetch trial.
A third experiment in 2006 examined the effectiveness of
the roller/crimper for control of winter rape (Brassica
napus) alone and in combination with glyphosate. In
the rape experiment, two application timings based on cover
crop growth stage were examined. In all experiments, either
Roundup Ready corn or soybean were no-till planted shortly
after rolling the cover crops, and glyphosate was used for
in-season weed control.
The results of the cereal rye experiment showed that the
roller treatment alone only provided about 50 percent control
of the cover crop. The rye was just beginning to head and
not yet susceptible to control with rolling alone. The combination
of glyphosate applied at either.093 pounds ae(acid equivalent)/acre
(1/8X) or 0.1875 pounds/acre (1/4X) with rolling provided
85 percent and 94 percent rye control, respectively, 14
days after application. The reduced rates of glyphosate
alone provided 67-percent and 89-percent control.
In the hairy vetch trial, rolling alone provided about
75-percent control of the hairy vetch and the addition of
2,4-D LVE increased control to over 90 percent. Again, the
hairy vetch was just beginning to flower and not completely
susceptible to control from rolling alone. Hairy vetch is
very susceptible to 2,4-D and application of 0.25 pounds
ae/acre provided effective control regardless of the roller
treatment.
Finally, rolling winter rape alone at either the early
or mid flowering stages of growth was not very effective
for control and a full rate of glyphosate (0.75 pounds/acre)
was necessary to achieve greater than 85 percent control.
Gylphosate applied half-rate at 0.375 pounds/acre provided
about 80-percent winter rape control.
The results of this research show that reduced rate herbicide
programs combined with roller/crimper technology can be
more effective for control of certain cover crops such as
cereal rye than either tactic alone. For other cover crops
such as hairy vetch and winter rape, the roller/crimper
is less effective for control and will require alternative,
complementary tactics or strategies for effective control
prior to establishing a cash crop.
Pennsvlvania
(southeast)
Dave
Wilson, collaborator
Dave Wilson, research agronomist
at The Rodale Institute, continued to conduct trails with
the Institute’s ongoing organic no-till research initiative.
Numerous trials were conducted at The Rodale Institute research
farm, and on-farm research was conducted with collaborating
farmers at other locations in Pennsylvania.
Trials included evaluations of small grain cover crops
(winter cereal rye and winter wheat) which were rolled down
for no-till soybeans. Ongoing evaluations included measuring
the representative biomass of these cover crops and the
corresponding weed biomass in these rolled covers to evaluate
weed suppression of the rolled mat. Soybean yields were
taken the last week of October 2006, and currently the yield
data, weed biomass and cover crop biomass data is being
analyzed and compared.
Several ongoing trails include evaluating the cover crop
hairy vetch for adaptation, winter survivability and early
rolling in a no-till system. In collaboration with Thomas
Devine, USDA ARS, 14 hairy vetch accessions received from
USDA as well as six other commercially available hairy populations
from various seed tag origins were planted and established
in the fall 2005.
These replications of small plots were evaluated and screened
for winter survivability, biomass and flowering date and
percent nitrogen tissue analyses. As a result of collaborative
research conducted at The Rodale Institute, USDA/ARS–Beltsville
and Penn State, Devine developed “Purple Bounty,”
which has favorable winter survivability, biomass production
and flowering date for utilization in the rolling/no-till
planting system. He will release it as a public variety
for development by seed breeders.
Other trials evaluating the cover crop hairy vetch for
the organic no-till corn system include:
- Evaluation of hairy vetch populations from different
seed tag origins.
- Evaluation of effect of planting date of the cover
crop.
- Evaluation for winter survival, biomass, and stage
of flowering and tissue analysis for percent nitrogen.
These populations were established in larger plots and
were rolled and no-till planted in 2006 with organic no-till
corn. These plots were harvested and currently the yield
data, weed biomass and cover crop biomass data is being
analyzed and compared.
Thick mat poses problems
We identified establishing a consistent plant population
in the heavy mat of the hairy vetch as a significant issue.
Some of our no-till roller corn-planting trials compared
seed-furrow closing attachments in this thick bio-mat.
Population counts were monitored across the plots to compare
the corn stand in these no-till plots. The adaptation of
cast-iron closing wheels on the rear of the no-till planter
was more successful in closing the seed furrow under the
heavy hairy vetch mat. These closing wheels provided better
seed-to-soil contact and led to higher corn populations,
which gave higher yields in these systems. This system also
prevented stand loss due to birds eating the germinated
seed out of the un-closed seed furrow.
Planter changes made a huge difference in our stands. The
average corn population in the field plots in 2005 was 17,
578 plants per acre; the 2006 average corn population was
26,511 plants per acre. This is a 51-percent increase over
the previous year’s average. Yield data, weed biomass
and cover crop biomass data are being analyzed.
Vetch seeding rate
One of the economic factors of the organic no-till system
is the input cost of the hairy vetch seed. Wilson has been
conducting multi-year evaluations comparing reduced seeding
rates of hairy vetch to full seeding rates. The reduced
hairy vetch seeding rate was accomplished by planting every
other row with hairy vetch-oats.
Additional trials were established which will evaluate
the suitability of various small-seeded legumes frost seeded
into winter wheat for rotational sequencing into no-till.
The winter wheat was over-seeded (frost seeded) with various
biennial small-seeded legumes in the early spring of 2006.
These will be evaluated as cover crops for rolling in year
2007.
Demonstrating early results
We held a successful field walk/farmer extension program
in June, conducted at Kirby Reichert’s farm located
in Lebanon County, near Hershey. Penn State Lebanon County
Cooperative Extension and The Rodale Institute coordinated
this event.
The field visit gave producers a chance to see the result
of cover crops that were rolled and the summer crop of corn
and soybeans no-till planted. Management practices were
discussed concerning planting rates for the cover crops.
The no-till roller design and utilization was discussed
and test strips let go to roll for the event were rolled
that day to demonstrate how the roller and no-till planter
combination worked in the field. Improved planter adaptations
should help soybean establishment at Reichert’s in
2007 after an unsatisfactory crop stand in the beans in
2006.
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