 |
| 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.
 |
