Success with No-Till Organic Soybeans: Getting That Good Weed-Free Stand


[ background music ] Success with No-Till Organic Soybeans: Getting That Good Weed-Free Stand>>Narrator: Produced by
University of Georgia Extension, North Carolina Extension, and the United States
Agricultural Research Service in Tifton, GA and
Beltsville, MD. With funding by Southern Sustainable Agriculture
Research and Education program. Demand for organic
soybeans is increasing. Organic dairies and poultry
producers use soybeans as feed, and are looking for sources of
organic grain in the Southeast. That said, consistent good
yields are hard to achieve, as weeds are particularly
challenging to control in organic soybean
production. Organic soybeans are usually
planted into plowed fields and receive numerous cultivations
for weed control. In total, 12-15 field operations,
including plowing, disking, cultipacking, planting,
blind cultivation, and between-row cultivation
are necessary for crop and weed management. The high number of passes across
the field increases fossil fuel use and can deplete
soil organic matter. If conditions are wet and
the farmer cannot get into the field, all of these
operations are delayed and weeds can quickly get ahead
of the soybean crop.>>Chris Reberg-Horton:
We’re here to talk about the
organic no-till soybean system. Our growers have been very
interested in the system for a number of years now because of
the problems they have with conventional clean-till
organic soybeans. When we have wet springs, we
get behind in our cultivation routine and weeds can be a real
problem in clean-till soybeans. This system that we’re seeing
behind us right here, we have a rye cover crop. We grow it up until it’s about
the soft dough stage; we roll it down; we plant
soybeans straight into it. When we follow that system we
actually find the exact opposite; it’s the wet years in which
this system really thrives. We hope that this system is
going to provide more stability both in terms of yield and weed
management for the growers and it’s going to ease their
logistics in the spring. Another advantage to the system
is we’re able to reduce our tillage which is a big
problem in organics. We’re very tillage dependent so
we have concerns over soil quality. We’re doing a lot of other
things on organic farms to help with soil quality. We’re cover cropping;
we’re using manures. But when we’re constantly
tilling the system, we can still have
soil health concerns. What this system does is we’re
changing when that tillage occurs. Instead of doing intensive
tillage in the spring, we’re now doing nothing in
the spring and we’re doing our tillage in the fall. Now that adds several big
advantages from a soil health concern and from soil erosion. One is when we plant a
cover crop in the fall; we’re going to plant
that with a drill. And so if we plant with a drill,
we can obtain quick canopy coverage and protect the soil. Contrast that with what
we do when we’re doing wide-row soybeans or corn. There we’re going to start
tilling February, March to get ready to plant
in April or May. By the time we’re done with
our cultivations and we’re starting to close canopy,
we can be months out from when we began tillage to when
we actually have complete coverage of the soil. If we can shift all of that –put
all of that tillage in the fall– we have a big gain we can make
there in terms of soil erosion.>>Narrator: Continuous no-till
is not really an option for organic producers,
but we do need to be working to reduce
the amount of tillage. Cover crop-based no-till
soybeans is one approach to reducing tillage in
organic grain production. This approach can be successful
by using the following practices: 1. Start with high levels
of cereal rye mulch. 2. Use a planter and make sure
it is set up to work in high residue conditions to get
good seed-to-soil contact when planting
through the mulch. 3. Use high soybean seeding
rates to ensure a fast growing cash crop that
closes the canopy quickly to choke out weeds. 4. Use varieties with
good early vigor. Successful no-till soybeans
require high levels of mature cereal rye cover
crop that has been rolled down to
form a thick mulch. How much? Try to target 8,000 lbs. of
cereal rye biomass per acre. Although 8,000 pounds of cereal
rye biomass per acre may seem intimidating, this amount will
control the weeds for about six weeks, allowing the soybeans to
develop ahead of the weeds. If you’re lucky enough to have
low weed pressure and aggressive soybean growth rates, you can
be successful at rye residue amounts between 6,000-8,000
pounds-per-acre. Rye, why? High biomass levels of cereal
rye mulches work well for no-till soybeans because they
inhibit weeds from establishing while living, and when terminated with a roller-crimper, they suppress
weeds by lowering temperatures and minimizing light
at the soil surface. Many weeds, like pigweed,
are stimulated to germinate by short flashes of sunlight. A thick biomass residue on
the surface of the ground reduces the light reaching
the soil surface. This delays weed seeds from
germinating, which reduces weed pressure as the soybeans
are getting established. If you use cereal rye to
accumulate no-till biomass, you can enjoy an
added advantage. As the cereal rye dies
and begins to decompose, it releases chemicals that
inhibit weed seedling emergence. This effect is
called allelopathy. How much rye do you need? Research shows that the
amount of weeds decrease as the amount of
residue increases. You might be more comfortable
trying to plant into smaller amounts, but 8,000 lbs.
per acre is the standard measure for
good weed control. So, what does this look like, and how will you know if you
have enough rye residue? The first field only
has about 4,000 lbs. per acre of rye. It will not provide
good weed control. The second field is close;
it has about 6,000 lbs. per acre but we would like
to see even more rye. The third field has the
right amount of rye. It has about 8,000 lbs.
per acre. Cultivate and manage your
rye cover crops as you would cash crops. This includes carefully
planning your timing, using the best
planting method, and paying close attention
to your soil fertility. Planting your rye. Use two bushels of seed
with a good germination rate and no noxious
weed seeds. The two bushel rate will help
ensure a good thick stand. You’ll get the best results
if the rye seed is drilled rather than broadcast. Planting date is a critical
factor driving cereal rye biomass because the more tillers
formed in the fall will result in greater overall
biomass in the spring. Cereal rye needs to be
planted by mid-September in the mountains, by the end of
September in the Piedmont and by Halloween in
the Coastal Plain. It’s best if you can plant
to rotate this crop phase into fields with good soil
fertility or apply fertilizer to get a good stand. Some growers apply poultry
litter in the late winter to ensure good growth. Generally 20 to 30 lbs. nitrogen
per acre is enough to promote the kind of growth
you’ll need. Timing is an important
consideration when terminating your cover crop;
the amount of biomass you’ll achieve
depends on it. Without the option of spraying
herbicide in organic production, killing a cereal rye cover
crop requires waiting until it is at the right
growth stage. Timing is critical. If you roll and crimp your
rye too soon, your cover crop will spring back upright,
or you’ll have regrowth as an added concern. You’ll know it’s the right time
to roll and crimp when the rye is well into flowering. At a minimum, make sure that
50% of the tillers in the field are well into flowering. Pay close attention to
whether most of the inflorescence is
covered in anthers. For added benefit, you can wait
until the milk or dough stage. Waiting until this stage can
increase your overall biomass production by an additional
1,000-2,000 pounds per acre. Here’s an example
of the milk stage. See how the beginning seed
seems to have a milky fluid when you break it
with your fingernail? Rye that is rolled-crimped
at the proper growth stage remains matted down on the soil
surface and forms a thick mulch; which is what you want! Crimp, don’t cut. A word of warning,
crimp, don’t cut! Crimping signals rye in the
reproductive stage to “cease and desist.” What’s more, crimped stalks
break down much slower than cut stalks, encouraging weed control
for a longer amount of time. Also, crimped rye laid
in one direction makes it easier to plant. There are a variety of commercial
roller-crimpers available. Many of these use a chevron
pattern to reduce vibration. Some farmers have even
made their own by welding angle iron to
old cultipackers. These have to be used a
low speeds since they tend to vibrate heavily. We’ve looked at rolling and
crimping, now let’s see how best to plant through
heavy residue mulch. The key to getting a good stand
is getting good seed-soil contact when you are
planting into the cover. There a number of approaches to
this and we’ll look at equipment specifically in a minute. Here are a couple of basics: You can either roll-crimp
and plant in one pass or roll-crimp and
then plant. Some growers also roll-crimp and
then roll-crimp and plant with a delay between the first rolling
and second rolling. If you use several operations,
be sure to plant the same direction you roll-crimp. This helps to prevent
hair-pinning and blowouts. For the rye to provide weed
control, try your best not to disturb or displace
the heavy mulch. Remember: the heavy, flat mat
of rolled and crimped rye is critical to maintaining
weed control. After you plant, it should
be difficult to see where the rows are. If you see wide strips of
soil, this is just creates an opportunity for
weeds to emerge. Let’s take a closer look at
some equipment that works. There are many variations
to this and you may set things up differently on your farm
depending on what kind of equipment you
already have. First, you’ll need a cutting
coulter out in front of the shank if you use
one, or in front of the double disc openers. You want this coulter to
be running on firm ground so it can cut
through the rye. In the Coastal Plain,
most farmers use a shank to break up the plow pan
that naturally forms in these sandy soils
over the winter. The cutting coulter should
be mounted at least a foot in front of the shank so
it runs on firm ground. In our research, smooth cutting
coulters have worked well. We’ve also liked using
these coulters with the plastic press
wheels on either side. These wheels help hold
the residue down so the coulter can
slice through. Yetter sharp-tooth row
cleaners can also be used to cut through the residue. These are best unit-mounted
in front of the coulter. Again, the idea is to cut
the residue so the double disc opener can get down to
the soil without leaving a lot of soil exposed. It can be helpful to wait until
the morning dew has dried before you plant, so the dry
residue can be cut more easily. You can use a fluted coulter
before the double disc opener if row cleaners are also used
to clear residue out of the way. This will help move residue
out of the way without opening a wide slit. Finally, you need think
about your closing wheels. Solid cast iron wheels work
well on some soils. Others require curved tine
closers or a combo of curved tine and solid steel
closing wheels. What you use will depend
on your soil and the moisture conditions. And remember, it’s always a
good idea to make a pass and then check for the right
planting depth and good soil contact. Then you can make any
adjustments needed. Soybean seeding rate is
important for obtaining good stands. Because organic soybeans do not
have synthetic fungicide or other seed treatments, you will
need to expect some losses. Most successful growers use higher
seeding rates to help compensate. The recommended seeding rates
are 200,000 seeds per acre or even as high as 225,000
per acre, if possible. Row spacing. Row spacing is an effective
strategy for increasing the competitiveness
of the cash crop. Use splitters and plant on
15” centers to decrease the time it takes to achieve
crop canopy closure. However, if you have high weed
seedbanks and a lot of perennial weed pressure, narrower row
spacings may provide more opportunities for
weeds to emerge. Unfortunately, this will
eliminate the option for high residue cultivation
as a rescue practice. For best results, select
seed varieties that germinate and grow quickly. Early vigor seed varieties
have the potential to grow faster than weeds, quickly
closing the canopy and discouraging weed
germination. Check with your local
Extension agent to find seed varieties that
grow quickly in your area. No-till organic soybeans can
be successful with good yields in addition to the benefits
for the soil of using a cover crop and
reducing tillage. Now that we’ve covered
the key aspects of developing a successful no-till
soybean production system, let’s review the
keys to success. Treat your rye cover crop
as a weed control program. This includes: Planting on time; Drill (don’t broadcast) two
bushels per acre of good seed; Fertilize with 30 pounds of
nitrogen per acre in late winter; Roll and crimp at the milk to
soft dough stage. Next, ensure good
seed-soil contact by: Using sharp cutting coulters; Using row cleaners,
if necessary; Testing planting depth; Using the right closing wheels. Select the right seeding
rate and varieties. Use a higher seeding rate
200,000 seeds per acre or even as high as
225,000 per acre; Use varieties proven for
your area with early vigor. Now that we’ve discussed how
to best grow no-till soybeans, be sure to visit the North Carolina Organic
Grain Project at the address listed
on the screen. For additional questions
specific to your area, contact your local
Extension office. Find your local Extension
office by using the address
listed on the screen. [ background music ] Captioning provided by:
2014 University of Georgia
College of Agricultural and
Environmental Sciences
UGA Extension
Crop & Soil Sciences Dept.

14 thoughts on “Success with No-Till Organic Soybeans: Getting That Good Weed-Free Stand

  1. love the information you guys had to offer on this video. Only thing I wish was different was that you had a secondary one for the Midwest region of the country. I love how you guys covered all the different areas from Quitman to the way you plan to what type of crops to put in for a cover crop. a lot of people don't discuss seeding rates or anything of that nature either! thanks again

  2. Sorghum Sudangrass is a little better than rye. Basically tills the soil itself. Mixing it with rye would help maybe.

  3. ummm just watching the planter you guys are using to plant soybeans and you got a dualed up 7000 series john deere tractor with the planter having to plant in to your tractors tire tracks you dip shits

  4. I may not agree with these production methods but I guess someone has to supply the market. I'm not against organic farming. It's just a shame the stigma it creates that gives regular "non organic" farmers a bad name, when in fact there is no scientific evidence to prove farming with modern herbicides can be harmful to consumer's health. I lived in the city for a few years while I was studying and was amazed how uneducated the majority of these "organic only" consumers were. They've never set foot on a farm, yet have a grounded opinion. Each to their own I guess.

  5. the problem I see is all these cover crop programs are using just rye for a cover crop. Try using a wide variety of cover crops like beets, vetch, peas and beans, etc. Each variety adds something different to the soil. With this type of cover cropping you can eliminate the fall tillage all together. If the goal is to do no-till soybeans why not no-till the cover crop too.

Leave a Reply

Your email address will not be published. Required fields are marked *