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>> Welcome and thank you for standing by.
At this time, all participants are in a listen only mode.
After the presentation, there will be a question and answer session.
To ask a question at that time, you may press star 1 on your touch tone phone
and record your name at the prompt.
This conference is being recorded, if you have any objections, you may disconnect at this time.
I would now like to turn the meeting over to Mr. David Lamm, go ahead sir, you may begin.
>> Oh, again, thank you.
I appreciate everybody's patience with today's webinar.
We've done 60 or 70 of this at least or more and have yet to have any technical issues
such as we face today with a slow server.
But, we will endeavor to persevere I guess.
So, anyway, I want to welcome you to this afternoon's presentation on Nutrient Management
in No-till Cropping Systems which I think is very timely with the upcoming planting season
and I trust that you all get a lot from Gene Hardee, his presentation here in a second.
But before we go into that, I just want to go through a few housekeeping chores so to speak.
And you should hopefully all be seeing a list of upcoming webinars that you need
to hopefully mark your calendars and participate in, in future events.
The next one coming up is Common Bees and Best Bee Plants for the East on April 25th.
And then one-- actually, the next one that's coming up is the Organic on May--
April 10th is one on Organic Pasture Management which will feature Joe Klein with Organic Valley
and our own Steve Woodruff who's the agronomist and grazing specialist here at the Tech Center.
In order to advance our technical capabilities and get the word out, we're offering--
we're moving into the world of Twitter.
And if you're interested in participating, we're giving away a free copy of the Building Soils
for Better Crops for the first five folks who sign up today
on the East National Technology Support Center, Twitter site.
And you can see the link there.
You can do that while we're going through my information but this is a bound copy
of this excellent publication on how you can improve your soil
and every NRCS person should have a copy of this.
We already have one question on how to get CCA credits and this presentation is available
if you are a certified crop advisor, you need to download the form which if you go
up on the tool bar menu on the right side, you should see the second icon left
of the word feedback, you should see what appears to be a stack of papers.
If you click on that, you'll see two documents there.
You'll see this form.
You need to download it, print your name.
Make sure you put your CCA number and sign it and get that back to Holli Kuykendall
at the information provided below, and I will remind you
of this at the end of the presentation.
But we don't know your CCA numbers, so if you don't put it
in there, you aren't getting any credits.
You want to ask a question?
The operator said, we're going to-- everybody is in mute mode, but during the presentation,
if you want to ask a question with Gene, I'll be--
I'll serve as moderator, you can type it in.
Again, you go to the top, the question and answer button there at the top
and you can type in your question.
And when I get a break in the action so to speak,
I'll let Gene respond to that appropriately.
So, those taken care of, I want to introduce Gene Hardee
who has been the senior agronomist here at the Tech Center
for many years and got a wealth of information.
And I think Gene's going to do--
share his experience, his knowledge
in presentation entitled Nutrient Management in No-till Cropping Systems.
So with that Gene, let me bring up your presentation.
And before I turn it over to Gene, I apologize
if these slides are loading slow on your computer.
There's nothing we can do about that, but we can make sure
that we'll be patient and just plug on there, so.
Okay. All right Gene.
>> Good afternoon.
In today's webinar, we will examine nutrient management under continuous no-till.
We will look at a number of facets including nutrient availability and soil loss--
or loss pathways rather; soil sampling and nutrient application, and companion practices
and treatment to further mitigate potential for nutrient loss.
Thanks a lot.
[ Silence ]
Historically, crop yield has been the overwhelming consideration
in nutrient management recommendations, but we're now looking
at optimizing returns and environmental impacts.
The 4 "s is a concept developed through a long history of cooperation
between the fertilizer industry and the scientific community,
the International Plant Nutrition Institute endorses and advocates the 4 R Strategy
as an appropriate nutrient management strategy.
And the NRCS Conservation Practice Standard for Nutrient Management defines nutrient management
as managing the amounts, source, placement, and timing of plant nutrients and soil amendments.
So basically for NRCS, we are also endorsing the 4 R's as a strategy for nutrient management.
Conventional or historic cropping systems are providing an abundant supply of food and fiber
but at a cost to the soil resource and the ecosystem.
With today's knowledge of the soil ecosystem and the technology available,
we can provide for more sustainable cropping systems.
Many of the concerns that are
with the conventional cropping systems also relate directly or indirectly to nutrient loss
and the cost of nutrient additions.
As we look at this list here of the concerns with the conventional system,
we note that most of these have some impact as I just stated, either indirectly
or directly with nutrient management.
There are four basic nutrient loss pathways or pathways for which we can lose nutrients.
This includes surface runoff, volatilization, leaching, and denitrification.
Of course, there are other ways for nutrients to leave the field with a--
particularly with the harvest of crop, but these are actually the four primary loss pathways.
In the poem The Road Not Taken, Robert Frost laments the loss opportunity
with The Road Not Taken.
But in nutrient management pathways taken often represent nutrient loss
and greatest efficiency is typically gained by minimizing the movement
of nutrients along these pathways.
And the loss in the surface on runoff, of course, phosphorous maybe lost in solution
or attached to a particulate matter.
The loss with nitrogen may be through these means or maybe nitrogen maybe lost
by a surface runoff or may not be.
Certainly with organic forms of nitrogen that are on the surface,
this can be a primary loss pathway.
However, with soluble nitrogen, typically, the rainfall will infiltrate unless
if the soil allows sufficient infiltration.
Normally, the soluble nitrogen will go into the soil with water infiltrating into the soil
and not be a-- the loss pathways of our surface runoff is not real high soluble
nitrogen generally.
[ Silence ]
Of course, the greatest change in no-till fertilizer
in nutrient management should be in the nitrogen management.
As we look at this slide, we see that nutrient losses under annual crops may range between 10
and 40 pounds under high rainfall environments, losses by ammonium volatilization
from surface-applied urea my range from 20 to 40 percent, and nutrient losses of nitrogen
as nitrous oxide from denitrification may range from 2 to 8 pounds per acre in humid regions.
However, there are also impacts on loss pathways for phosphorous
and these must also be considered.
Let's look at the potential impact on no-tillage cropping systems on losses
through surface runoff and leaching.
This slide has a number of pictures from a study that was undertaken by Dr. Charles Raczkowski
who is an agronomist at North Carolina A&T University here in Greensboro, North Carolina.
This particular-- in this particular study, Dr. Raczkowski was looking at the impact of cover
and no-tillage on runoff and soil loss.
And this particular-- in this particular study, each of these plots was set up with a weir
and for a sampling mechanism to measure the runoff and the sediment.
But let's look at the focus on the pictures themselves.
And this was following a rainfall event of 1.8 inches on the morning of June the 12th, 2006.
This is a kind of the nature of a picture is worth a thousand words sometimes.
But in this particular case, the pictures on the left are those for situations with no cover.
The two on the right are for situations with cover.
Of course, the ones on the bottom are no-tillage and the ones on the top are ones--
are treatments which have tillage.
But notice-- look at these slides and you will note that the water expanding
which is making its way up the field and runoff and you'll note that--
the highest water that we see there is the top left where there was disk
but no cover followed by the no-tillage with no cover.
And by the no cover, that's meaning no cover crop rather
than meaning no surface cover on the field.
Then the-- actually, the disk cover probably has the less runoff than the no-tillage
with no cover, but that's probably a short term thing in terms
of the growth period-- growing season for the crops.
But look at the no-tillage with cover and you'll note that there's essentially no water
that you can see standing within the plots.
So basically, everything within those plots that had no-tillage
with cover is infiltrating into the ground.
So the point to make from this particular slide is that if there's no runoff,
then there's no loss on nutrients through this particular loss pathway or surface runoffs.
So-- but certainly this is-- keeping good cover on the land is very important in terms
of providing cover that is needed.
>> Yeah, Gene let me interrupt you here a second.
I'm getting several questions about the fact that it's--
you're not seeing the slides or they're not loading.
Again, I apologize for being-- the server problem we have.
This is being recorded, so the replay is-as are all of our webinars,
is available off of the Science Technology Training Library and generally is
up by the following Monday or off of the East National Technology Support Center website.
Either one of those will get you replays of this.
So I think I'm just going to have Gene continue to plug along here.
This is going to be recorded.
I would encourage you to stay with us and listen to as much as you can.
And again, I apologize for the poor quality that we're getting today, so, Gene.
>> Okay. In the next slide, this slide entitled Effect
of Tillage System on Annual Phosphorous Runoff.
This is from a study that was done at Kansas State University.
In this particular study, there was a comparison of phosphorous runoff
under chisel-disk tillage system and a no-till tillage system.
Also, there were treatments-- split treatments they head one
with broadcast phosphorous fertilizers and another
in which the phosphorous fertilizer was not down or injected into the surface.
The-- in this case, you will note that the sediment attach phosphorous
from the no-till was much less than that from the chisel-disk,
but total phosphorous was much less from the-- was less from the no-till.
But the soluble phosphorous on the no-till was somewhat higher
or was significantly higher than that from the chisel-disk.
Kansas went further though, one thing in this-- from this particular study,
they found that knifing in the phosphorous reduced the phosphorous losses by about 1/2.
There was also a study in Wisconsin by Bundy that showed similar results and also a research
at the University of Maryland on deficiency for surface-applied phosphorous under no-tillage
to be greater than conventional tillage.
And a study at Iowa's State University Tech, and this is a step further though,
they found that they got the same differences in which they got more loss of soluble phosphorous
by surface runoff but that loss pathway if it-- if the fertilizer was surface-applied,
then they did that with conventional tillage plots.
But, they found that that difference was primarily the first few rains
after the application that they found that that difference diminished throughout the season.
So finally, they were-- there's two--
the situation for no-till in terms of phosphorus loss, loss of soluble phosphorus
and for the conventional till plots were essentially the same.
In terms of leaching of nutrients, or looking at leaching for a moment as a loss pathway,
characterized primary nutrients in terms of their mobility.
All of you are aware that nitrite-- nitrogen is very mobile,
so it's subject to loss by leaching.
Phosphorus is relatively immobile.
However, it is- too is subject to leaching through coarse textured soils
and through preferential flow, particularly when soluble phosphorus levels in the soil are high.
Potassium is between nitrogen and phosphorus in terms of mobility.
And the potassium will leach through coarse textures but typically is deposited
at the top of the subsurface clay layer.
>> Gene, we had a question come in about the phosphorus.
Is the form and placement, how could you overcome
that with the no-till system would study such that they were just broadcast or was it's--
where it's put side by side with a planner, excuse me.
>> In this particular study, I cited earlier, there were treatments with both with phosphorus
that was broadcast, both for-- both tillage treatments and also for both tillage treatments,
there was treatments that in which the phosphorus was not in.
I'm not sure I understand the whole question David,
whether in terms of-- means of reducing the loss.
We're looking at this particular-- at that particular point in time in terms of losses
by surface flow and-- but, certainly the reduce and the losses--
the loss by surface flow injection or banding would certainly be a way to minimize that loss.
There are other ways to minimize the loss of phosphorus by polymer coating of the phosphorus,
some new technologies that are becoming available
that might also minimize some of the loss pathways.
But the primary loss of phosphorus, the primary way
of reducing the loss via surface runoff would be to actually put the phosphorus into the ground
through injection or some of the other things providing cover
which we'll get to a little later.
In terms of leaching occurring on in terms of contrasting between no-till and conventional
and there was a 1936 study, I know this goes back a long time, but still in some cases,
old research can still provide some valuable insights.
But there was a 1936 study by Dr. R.E. Horton in which he proposed that cracks, earthworms,
insects, and root hair perforations enhance infiltration.
And the reason going back to that particular study that was one of the first studies
that cited preferential flow as having a significant impact on movement of
or loss of nutrients from the soil.
Many scientists have concluded that there's greater potential for leaching
of soluble nutrients in no-till due to higher moisture
and also that it has a preferential flow.
If we look at the bullets here on the slide,
you'll note that several studies have found little difference in leaching of nitrate
between no-tillage and conventional.
But at the same time, other studies particularly
in more humid areas have shown greater leaching potential in no-till soils due
to preferential flow and increased soil moisture.
Studies at the National Erosion-- sediment--
Sedimentation Laboratory have found that no-till produces more macropore flow.
So where does the preferential flow in the profile and the soil profile end?
That is a good question, but it depends on the soil moisture, the soil type and et cetera.
The leaching through the preferential flow has become a special concern
for fields with tile drainage.
And research at the USDA-ARS Sediment-- National Sedimentation Laboratory in Mississippi,
it's been demonstrated that matrix flow contributes the majority
of the water moving through tile drains.
The next point, that preferential flow contributes disproportionate amounts
of soluble nutrients to tile drains
and that no-till produced more macropore flow than tile drains.
The 1990's research project in Norway that demonstrated significant potential for soil loss
through the flow of macrospores to tile drains, this was the first study I found
that actually demonstrated significant soil loss,
actually of the actual soil particles themselves actually going
to into the tile drains and contributing to soil loss.
But that would certainly depend on the soil type.
But in this particular study, it was actually it was--
the slopes were relatively flat but there was actually more soil loss actually moving
to the tile lines than there was by overland flow.
In a study in Cornell University in comparison of soil columns from conventional
and no-till soils, they looked at the-- these columns and found that nearly the entire depth
of the no-till column are short circuited
by preferential flow before the till column solute had passed
through the mix unstructured plow layer and where basically in the no-till field,
the flow passed readily through the macropores in the study at Cornell.
Whereas in the conventional till, it was passed-- had to pass through the plowed layer--
slowly passes through the plowed layer as a whole unit, as a continuous,
as a uniform flow before it reached the macropores.
[ Silence ]
>> And a study in Hancock, Indiana, this was a study by US Geological Survey,
they found that 25 percent of the nitrogen and 1 percent
of the phosphorus loss was through tile drains.
They further found that no-tillage increased infiltration.
They found that macropores and no-till typically were continuous
to the surface or on the other surface.
Also, they found that preferential flow increased the loss
of soluble chemicals through tile drains.
And finally, they concluded that conservation practices to minimize surface runoff
and erosion may not reduce the transport of soluble nutrients through tile drains.
Basically, citing these particular studies to kind of lay the ground work for some
of the treatments that we will be looking at as we proceed on through the discussion and notice
that a lot of information that is kind of being thrown out that there is also additional factors
or the nutrient pool which may be impacted by no-tillage that we need
to spend a few minutes looking at also in addition to the loss pathways.
These are the nutrient placement, impacts on soil moisture and temperature,
stratification, and also nutrients availability.
First in looking at nutrient placement, nutrient loss particularly through volatilization
and with surface runoff is significantly reduced by placing the nutrients into the soil.
Continuous no-tillage may inherently restrict the opportunity for placement of nutrients
in the soil or mixing of the nutrients with the soil material thoroughly.
Maintenance of residue may limit opportunities for incorporation of nutrients and mixing
of nutrients through the surface layer.
Not-- special equipment may be needed for injection and banding of nutrients.
High residue cover can also contribute
to increased volatilization of surface applied nitrogen.
Surface broadcasting of fertilizers can increase the potential for loss with surface runoff.
And finally, the differences in rooting patterns
under continuous tillage-- continuous no-tillage.
Normally within conventional tillage system, you have a relatively few roots
or a smaller percentage of the root system in the uppermost part of the surface as compared
with no-tillage, with no-tillage with real good cover and bulk
of the rooting system tends to be close to the surface.
Of course, you must still get deep rooting depth but proportionate as close
to the surface differ typically between continuous no-till systems
with good cover and conventional till systems.
Just a few notes relating to soil moisture and temperature and impacts in no-tillage
and soil moisture and temperature, surface cover affects both soil temperature
and the moisture content which can affect plant growth and nutrient movement.
Lower soil temperatures under no-tillage can slow root growth and microbial activity
in the early spring due to cooler temperatures,
but no-tillage can actually moderate the soil temperatures during the warmer parts
of the summer providing better conditions for nutrient uptake and plant growth.
Also, increased infiltration and lower evaporation can add soil moisture
and increase the flow of nutrients through the soil.
This particular slide here is from a study conducted by Shanholtz
and Lillard at Virginia Tech University.
In this particular slide, it just demonstrates -or provides a comparison
of the available plant soil moisture under no-tillage conditions versus conventional till.
The difference is not huge, but if you look at this particular graph and note that for both--
the 0 to 6-inch layered and the 0 to 12 and when there's also increase to 0 to 18.
In each case, the available soil moisture--
accumulated plant available soil moisture is actually higher--
significantly higher for no-tillage than for the conventional tillage system
which basically points out the increased moisture and the value of no-tillage
in providing moisture for plant growth.
This particular data here was actually on, I believe,
the third year of the no-tillage system coming out of a sod crop pasture or hay land situation
that there-- or other years in the study which basically provided similar type results.
No-tillage also has, again, impact soil temperatures
in this particular slide, this was from a study.
It was actually done in Brazil.
And-- but you will note in this particular study the moderation of the soil temperature
by the no-tillage treatment-- I should say, the lowest--
the line with the lowest altitude curvature there is actually a no-till plot.
And when you compare this to the conventional till and the--
or the chisel plow, you'll note that there's significantly lower temperatures
through the daytime portion that is given in the graph there than there is for--
with the no-till-significantly lower temperatures
than it is for the other two treatments.
Next, we have a picture that is actually from Stanly County, North Carolina.
This-- in this particular picture, you will note-- this picture was taken by Nathan Lowder
or provided by Nathan Lowder the district conservationist in Stanly County,
and this was taken on July the 13th, 2011.
You will note in this slide two contrasting findings
of cotton belonging to two different farmers.
The one on the left was no-tilled into a cover-crop mixture
with a rye cover-crop along with a legume in the mixture.
The one on the right was conventional tillage situation
that was turbo-tilled twice before the planting of the cotton.
The cotton on the left was planted on May 18th of 2011 and the cotton
on the right was planted on April the 21st of 2011.
So the one on the left which nearly-- that was essentially three weeks later than--
or maybe low-- over three weeks later than the one on the right.
In this particular situation, Nathan took the soil temperature on July the 13th 2011
and he took it 1 inch below the soil surface at approximate 2 PM
and the temperature was taken from the row middles.
And he found that the soil temperature on the conventional till plots on--
field on the right was 104 degrees, the soil temperature
on the field on the left was 85 degrees.
That's nearly 20 degrees differs in soil temperature.
So this demonstrates that the value-that no-tillage or in with a good cover can provide
and providing a better environment for plant growth in the soil biota.
Now, looking at the causes of nutrient stratification in soils and the causes
of that stratification under continuous no-till, there's basically four reasons
or four contributors to stratification under continuous no-till.
First is immobility of lime and some nutrients such as phosphorous, limited so mixing,
acidification from surface application of Urea and ammonium based nitrogen fertilizers,
and finally, delivery of nutrients to the surface to the natural cycling of the nutrients,
that is by plants with deep roots systems pulling up nutrients from lower levels
and depositing those nutrients in decaying residues on the surface of the soil.
Basically, roots tend to grow towards area--
the concentration of nutrients and this is probably the reason that most studies have found
that even-- where there was stratification of nutrients that it didn't seem to impact
because of the fact they're getting a higher concentration of roots in the layers
that actually have those higher concentration of nutrients.
[ Pause ]
>> Gene, we've got a question that come in here while you're pausing.
It says, wants to know two things what role does organic matter play
in a no-till cropping system related to nutrient management?
>> Well there are several things that-- organic matter provides a better environment
for plant growth and uptake of the nutrients, a better environment for the soil biota,
but it also provides nutrient cycling.
Basically, it provides a continuous release of nutrients for plant growth, the nitrogen
and phosphorous as well as other nutrients.
And we will be getting to some of those points
in a little more detail as we go on a little bit later.
>> One other question related back to your--
the study with the macropores and going to the tile line connection,
do you know if that study factored in roots.
Were those done with living roots growing in the soil?
>> The-- I don't think those particular--
those particular studies were not done with cover crops.
I do have some information later on in the presentation
for we will be bringing in, the impact of cover crops.
>> Okay, good.
>> This particular study, graph rather, chart on the--
that you see is from some information about Douglas Beegle at Penn State University.
And basically, this particular graph suggests are to demonstrates the studies and the fact
that we do get some-- can get stratification of nutrients within the surface layer.
And the particular graph that you see displayed, this is actually a contrast of the soil pH
within no-till treatments versus conventional till treatments.
And you noticed in the conventional tillage that the-- for each one of those split,
increments in the top 6-- top 8 inches rather, the pH levels are essentially the same
but if you look at the no-till, you will note that levels on this--
that the pH level on the surface to 0 to 2 inch layer is significantly below the rest
of the surface profile or the surface layer there.
So basically, we get stratification, in turn, we generally get lower pH in the surface layer due
to the acidification from surface-applied nitrogen and that's a major contributor
to the lower pH on the surface and where you get a no-till situation
if nitrogen is surface-supplied.
In the next graph also from Douglas Beegle, this focuses on the impact on soil test phosphorous
at the-- conventional till and no-till.
And in the conventional till situation, you will note there is a spike in the phosphorous level
under the conventional till and that is actually from the placement of starter fertilizer.
And if that should-- still showing up in the results later in the season,
but that's the only impact other
than that particular spike there due to the starter fertilizer.
Throughout the 6 inch depth, the phosphorous levels are essentially the same.
But if you noticed in the no-till plots, there is difference of the surface layer to 0
to 2 inch layer has much higher concentration of phosphorous.
Phosphorous is immobile as we noted earlier in the presentation or generally immobile,
so you don't get much movement down onto the profile with--
or the movement is very slow with the phosphorous.
So you get-- if the surface-applied, then it tends to remain into the surface.
Both phosphorous and potassium are relative immobile, so they will move but you have
to get high levels incrementally as you get movement
down of those particular nutrients generally.
The next slide here shows another study by-- it was conducted in Canada by Dr. Ivan O'Halloran.
And in this particular study, you will see again
that you have stratification of the nutrients in no-till.
You have a wide difference between levels of phosphorous in the upper part of the surface
versus the lower part of the surface.
We'll note here that this particular graph is actually in centimeters and I'm just making
that note to you to-- as an explanation.
Actually, the actual movement of phosphorous is--
the decline is much more rapid in terms of depth and we might get the impression
if you're thinking of that as being inches on your first glance there.
One more study is looking at stratification.
In this particular study, this was a study from Purdue University.
And in this study, it looked at both phosphorus and also potassium and looked
at three treatments, plow, chisel, and no-till treatments.
And you will notice again that this study also show stratification for the no-till.
But one thing to note here is that also showed nearly the--
close to the same stratification with chisel systems as it did
with no-till-- the no-till treatment.
to eliminate that stratification would take a fair amount of mixing
such you would have in a plow-- turn plow situation.
But certainly, that would open up the sole to a lot of other concerns.
>> Yeah Gene, we had a question come in related to the Beegle study and they had a question.
It was said that it wasn't showing stratification with the respect to depth
but it was showing changes in P content with respect to distance
from the crow-- row middle crop row.
And I could go back up to that, I just-- I don't know--
they were just wondering if you had a comment on that.
I think it's the bottom there.
>> Well, it does-- and actually, if you look at the depths there and look at the line,
these are the distances from the row middle.
But if you look the-- at the soil test level throughout the whole arrangement there
from the row mid, you'll note that the-- on the no-till, the concentration within the 0
to 2 inch depth is significantly higher than it is for the other increments.
And if you look at the convention till, the actual concentration
of phosphorous is essentially the same throughout other than this one spot there
that is caused I believe-- David, I believe you're on the on for the pH there rather
than the one for the phosphorous, thank you.
But despite there, in the top graph there for the convention no-till, that is due to the--
or Dr. Beagle attributed that to being due to the area there close to the row
where you had starter fertilizer.
Everything else in the conventional has essentially the same concentration
of phosphorous.
If you look again at the no-till, you will note the higher concentration in the 0
to 2 inch depth than any other 2 inch increments, so.
>> One more-- I hate to bug you here Gene.
Another question is why do all the studies assume surface application
and nutrients in no-till.
And I guess that's just the preferred method.
>> Well, that-- that was a main-- this was to look at these-- if--
one of the ways of overcoming that is not as to assume that that's--
there's going to be surface application.
But it's just looking at what the problem would be with surface application.
Of course, one-- the best way to overcome the problem of stratification is
to place the nutrients actually into the soil and not only to overcome the problem
from stratification but also overcome potential for loss of nutrients with surface runoff,
the best way to handle that is to actually place the nutrients into the soil by injecting
or banding the nutrients in sub-surface bands.
>> One quick thing Gene and I hate-- Gene has been a real trooper, let me interrupt here.
So folks, I've got a couple more comments.
Some person-- one of the folks in here suggest that if you're having trouble,
you can print these-- Gene's slides out just down on the right hand corner,
there's a printer, you can print the PDF.
Actually, print them out or you can save them to your hard drive and review them that way.
So you may try to do that if you're still having trouble.
Again, just to remind folks, we're having issues with servers that are beyond the control
of the two or three of us here in the little room we sit in, in Greensboro, North Carolina.
So Gene, I'm going to let you keep going there.
>> Okay, continuing on in terms of the-- these special factors or special influences--
additional influences related to impacts in no-tillage.
Nutrient availability would be the next one.
And just a few things we need to consider in terms of nutrient availability and the impacts
in no-tillage cropping systems is the cation exchange capacity or influence
in cation exchange capacity, the nutrient tie-up and organic matter including the tie-up
and soil biota, nutrient cycling and not just nutrient cycling but also the continuity
of the release of nutrients, availability of micronutrients
and also the increased mycorrhizae population.
As we look at these of course in regards to nutrient tie-up, this is particularly
about organisms decomposing organic material with a wide carbon-nitrogen ratio.
And microorganisms can free up nitrogen from the soil as an energy source
for decomposition of high carbon organic material.
Stubble decomposition tends to tie up nitrogen particularly in the early years of no-till
and after the early years build up as organic matter application
and that should likely be reduced.
One thing I like to note there in terms of availability of micronutrients is
that organic matter provides a natural tillage that maintain micronutrients such as zinc,
copper, and manganese and in forms that the plant can use in this.
One thing we don't hear too often in terms of no-tillage and its benefit in terms
of the soil organic-- its impact and so organic matter buildup
of soil organic matter is its impact on nutrients other than those primary nutrients.
Continuing on and looking a moment at the cation exchange capacity
and the impact on cation exchange capacity.
This is a table or-- I'm sure all of you have probably seen similar tables
from a basic soils 101 course or some lower level soils course.
But basically, this table shows the cation exchange capacity
of various types of clays and also humus.
And you will note- that humus has the highest cation exchange capacity potential
of anything listed there.
So it does have a lot of value in adding to the nutrient holding capacity of soil.
Of course, the cation exchange capacity of those humus as well as kaolinitic clays
as you know is pH dependent meaning that to realize that cation exchange capacity,
you'd only have to have a pH of about 6 or somewhat close to 6.5.
This particular slide here is related to nutrient type
and nutrient cycling and the continuity of release.
A lot of the soil analysis reports that you see now will have a factor--
a parameter listed as the ENR or the Estimated Nitrogen Release.
This is a credit for nitrogen release from the mineralization of soil organic matter.
Basically, the estimated, as I said this stands for Estimated Nitrogen Release
and it's the natural release by mineralization of nitrogen during the crop season
which is available for plant uptake and the ENR should be taken into account
as a nitrogen credit for the nutrient budget.
For those of you in northern part of the US, you probably have seen this output
on a good bit on soil analysis reports.
For those in the southern US, you may not see this because the soil organic matter is so low
in the southeastern US or the southern US that most of the times, the labs don't really worry
about this in their reports or the recommendations.
They don't worry about that particular nitrogen credit.
In this particular slide here, this is a slide that was from an article,
going back in time somewhat, this was an article for 1938.
Year Book of Agriculture is a study
by Dr. William Albrecht, but still some good information.
This particular study shows a nitrate release on soils with continuous cropping of- corn.
And you'll note that this is a long term study from 1920 through 1932
and note the declining release of nitrogen and also the timing of the release of the nitrogen
as the years of conventional tillage went on.
So basically, what Dr. Albrecht was showing in this particular study was that with the passage
of time, the soil organic matter and potential to release nitrates was being eliminated
and we have seen this impact basically with the declining organic matter in many soils
in the country and the corn belt and other areas and also with the subsidies and a lot
of organic soil such as the Everglades, there is lower potential for those soils
to release nutrients and because of a lot of declining--
decline in organic matter basically to-- even though the organic matter--
so organic matter has a potential to release nutrients to provide for plant growth.
the organic must be maintained, the cropping system also must be able to maintain that
or that credit, that nitrogen and other nutrients that are being released
through that decomposition or mineralization of that organic matter is going to cease.
As for the estimated nitrogen release, basically, that normally amounts
to about 20 pounds of nitrogen for each percent of soil organic matter.
Actually, most of the labs use somewhere in the range of 15
to 25 percent depending on the region.
And as for, what goes into that particular computation, if you look and follow
on the slide, you'll notice as an example,
a soil with 2.5 percent organic matter has an estimated nitrogen release of 50 pounds,
that is the 20 pounds per percent, organic matter times 2.5 would give to 50.
And as what really goes into that, if you look at acre furrow slice,
constant is about 2 million pounds and 1 percent organic matter.
So organic matter would be about 20,000 pounds if you assume an annual mineralization rate
of soil organic matter is between 1 to 3 percent adjusted for geographical regions
in crops the estimated nitrogen release based on the rule of thumb.
So organic matter contains around 5 percent nitrogen then you would have about 10 pounds
to 30 pounds for nitrogen for each percentage in the organic matter.
So basically, the midpoint of that was the 20 which was used in the study
and for the credit that is given by labs.
Actually, in terms of the annual mineralization of soil organic matter,
it's listed here as being around 1 to 3 percent.
That is for the areas that normally get this credit.
As you move farther south, the mineralization due
to warmer soil temperature would be even higher than that,
probably in the southern US closer to 5 percent.
Well how do we build and maintain soil humus
that has the potential for cycling these nutrients?
Just a few comments here in related--
in relation to that, as Albrecht demonstrated earlier continuous cropping without additions
of organic matter soon depletes the organic matter.
So it's important that we have crop systems with the potential to maintain--
certainly maintain but hopefully even build with the current status of soil organic matter
to build on the soil organic matter.
Of course, organic matter is relatively stable in the soil as we saw in the previous slide,
in most areas of the US, about 1 percent is mineralized annually
but it can be even more than that.
Another thing is soil disturbance significantly increases mineralization or humus,
so under conventional tillage with a lot of soil disturbance,
that mineralization could go quite high.
Continuing on, it takes about 10 pounds of organic materials to produce one pound of humus,
a large quantity so a large quantity of biomasses needed to build soil organic matter.
But approximately 65 percent of the carbon in organic matter is given off
in carbon dioxide due to microbial respiration.
The carbon-nitrogen ratio of humus is around 10 to 1.
So it takes not only carbon but also it takes nitrogen in order to build soil organic matter.
If there is not adequate nitrogen available, then--
even more beyond that 65 percent of the carbon will be released to the atmosphere.
Note that the bodies of bacteria have a carbon-nitrogen ratio
of around 4 to 1 to 10 to 1.
So that it does take a good bit nitrogen for the soil biota to carry on the functions
of decomposition of the organic matter to fix--
organic material rather to fix out soil organic matter.
This particular slide shows the-- is function work by Dr. Ray Weil at University of Maryland
and it shows the influence of predatory nematodes on nutrient cycling.
One of the reason I included this just to show the nutrient release in a healthy soil
so we do get a lot of influence by the soil biota.
And the predatory nematodes are good indicator of a healthy soil in contrast
to parasitic nematodes of course.
But a healthy soil does release a lot of nutrients, but it also has ability to capture
and cycle a lot of nutrients also.
And in terms of the soil biota, we might mention here
that there's this particular soil condition has a lot of influence on the particular soil biota.
A soil with high pH for instance favors the bacteria and a soil with low pH favors fungi.
And one reason I mentioned that is that fungi or particularly mycorrhizae fungi is very important
to the crops in terms of helping assist the crops basically as an exchange
in the root system and helping the crops to glean immobile nutrients such as phosphorus
which their new root system might not be able reach
without that assistance from the mycorrhizae.
Basically, the mycorrhizae get sugars from the plant and in turn, they provide nutrients
that are difficult for the plant to reach.
With considerations on some these impacts on nutrient losses and nutrient availability
by conservations, by no-tillage systems,
let's look at some basic nutrient management guidelines in terms of what we would do
or recommend for production of crops in no-till systems.
First of all, we should-- as a starting point, we should sample the soils and make adjustments
for those immobile nutrients that is-- make adjustments in the soil pH and the levels
of less mobile nutrients prior to implementation.
The second thing we should follow-- university recommendations on sampling of continuous
in no-till soils a couple of points there, normally, the recommendation is to split
of sampling depth on soils that are continuously no-tilled at least periodically.
And the university guidelines on how that should be split differ from university to university.
Some recommend a 0 to 2 and then the rest of the top soil area in other increment.
Some recommend to even split between the-- of the surface.
So basically, they do differ but all the universities recommend some sort of split
up periodically in terms of the sampling to assess stratification
and to refine nutrient management strategies.
also, a number of universities also make a point to recommend that the sampling be adjusted
to account for spatial variability.
Because if the nutrients are being injected in bands, then you still have the potential
for spatial variability and in order to compensate from that,
most universities recommend that there be more subsamples--
more sub-sampling in collecting soil samples or that there'd be a separate sample taken
for the row area where the nutrients would likely be injected versus the row middles.
And finally, in terms of this particular slide and the recommendations, the last thing there is
to develop a nutrient budget that credits all nutrient sources
and that should include the estimated nitrogen release, nitrogen from nitrogen fixation,
manures, compost, and also fertilizers.
In terms of nutrient adjustments, we also might note that we solve the stratification in pH
in association with no-tillage, we note that lime applications could be more frequent
under no-till, but generally, we would have lower applications than you would
under a conventional till situations.
Continuing on with the basic recommendations, basically, standard recommendation is
to adjust nitrogen application rate and timing as needed to account for building
of soil organic matter on top of nitrogen by soil microorganisms.
As we discuss briefly earlier, you might need more nitrogen as you go into a no-till system
but later on as the soil health improves and you get more release of nitrogen
from organic matter, you should be able to lower that nitrogen application.
Also, you might have to apply more nitrogen upfront in terms
of as before the crop is planted versus a lay by or side dress application as compared
to a conventional till situation.
The next thing is to use starter fertilizers for early climate crops and for crops
with inherently slow root development.
Basically, the research has shown pretty consistent that the results from application
of starter fertilizers are even greater with no- tillage than it is with conventional tillage.
And just a couple comments, remember that nitrogen and potassium are salt,
so you have to be careful about how close and how much of nitrogen
or potassium fertilizers are placed in proximity
to the germinating seedlings or the plant's root system.
Normally, a 2 by 2 application is recommended for starter fertilizers that is 2 inches away
from the safe placement and 2 inches below.
But that is not necessarily true for all crops.
The next thing there is to use banding or injection for application of nutrients
to minimize the potential loss and to improve nutrient use efficiency.
In terms of injection, I pointed out in the-- throughout the presentation,
the concerns with leaching and particularly in terms of leaching on tiled fields
because leaching to the level of the tiles through macropore or preferential flow
and having a direct outlet out of the fields into water waste is important.
Some scientist make the point that it is important to avoid injection direct
over the tile lines were possible.
And also maybe adding some sort of wings to injectors to disrupt the macropores to help
to seal off somewhat the direct flow into, to tile lines
[ Pause ]
Asking. Okay.
There's also a number of companions practices or treatments that I will list here.
These are not just limited to no-tillage but there are some things that could be used
to reduce the loss of nutrients under no-tillage.
The first one the list it is fertilizer additives, this would include urease inhibitors
and also nitrogen stabilizers and also, there's some new technologies
for phosphorus stabilization to stabilize soluble phosphorus fertilizers and that
which involve polymer coating that slow down the release.
Other companion practices that we have listed here is drainage water management
which you basically includes in line water control structures.
Irrigation and water management, the next one is bioreactors
which is basically a new technology involving inline treatments consisting of wood chips
or other organic materials in the trench basically to create an area for denitrification.
There is one concern with that is that the denitrification can also release nitrous oxide
which is a greenhouse gas, so that we might be reducing the movement
on nutrients into water bodies.
We might also be increasing the release of greenhouse gas with the bioreactors.
And last of the companion practices or treatments is filter strips or buffers.
There have been a number of studies that have shown that those filter strips
and riparian buffers can also provide some value
in reducing both total phosphorus and also soluble phosphorus.
One thing to note on this, note most of these are actually impact, the loss on the field
but don't really directly influence the nitrogen or rather the nutrient utilization efficiency.
Now, let's move to some management that goes beyond just no-till.
And look at these strategies, these management practices that have a lot of potential
and actually reducing the nutrients loss from the field.
These include adaptive nutrient management, on-farm trials, injection of animal manures,
application of gypsum and diversity in cropping systems.
Going back to adaptive nutrient management, the potential impact of organic matter--
of nitrogen availability is well documented.
But there are limitations of the presence of soil test methods for phosphorus and sulfur
in that they only measure soluble forms and do not properly account for the contribution
from mineralization of the organic forms and management histories.
There was some research done at Maryland a few years back that showed
that approximately 40 pounds per acre of phosphorus on no-till corn is often equivalent
to 80 to 120 pounds of phosphorus on conventional corn.
Based on this particular study in Maryland,
they have significantly reduced soil test based recommendations for no-till corn.
Every university does not have this supporting data to adjust the recommendations,
so this is one area that on-farm trials could support adjustment on individual farms.
adaptive nutrient management is not for every farmer to take home
but certainly it is something that could be very helpful
in increasing the utilization efficiency on the farms.
The next thing is injection of animal manures.
Of course, injection of animal manures can provide for better crop response,
reduce volatilization, reduce loss of phosphorus, nitrogen and fecal bacteria
and surface runoff, and also reduce odor.
Of course, this technology for injection of liquid manures
and slurries has been available for a number of years.
However, injection has potential to significantly reduce the loss of nutrients
through surface runoff and volatilization.
Thus, it is important practice for management of nutrients in no-till cropping systems.
There are some considerations with injection of animal manures though
and these include surface residues or standing crops can be an obstacle.
Next, we may create significant soil disturbance such as that--
the unit that we see in this slide here is creating significant soil disturbance
and may lead to surface rough, contaminants from inject of manure are closure
to till drains and also equipment availability.
Equipment, it is available commonly is limited to injections of liquids and slurries.
But that's hopefully not just the case in the future.
There is equipment being developed
that facilitates the injections of poultry and other dry litter.
There'd been two parallel efforts by ARS.
One at the Soil Dynamics Laboratory at Auburn University and another
at ARS Dale Bumpers Small Farms Research Center in Booneville, Arkansas,
and you will the two prototypes at the top there that came out of this research effort.
Agricultural Research Service applying for patents on these and one company has applied
for a license to commercialize it.
There's a coalition of Agricultural Research Service and agricultural scientists working
to promote this unit across five Chesapeake Bay states.
And the coalition is led by ARS scientist, Peter Kleinman,
and research partners at Penn State and Virginia Tech.
Also the Sassafras River Association in Maryland has a custom prototype unit
that they are making available for demonstrations in 2012.
And I think there was also a custom prototype unit that was used for demonstrations
and made available to producers within a CIG project in Pennsylvania.
In addition to this, there's also been a unit developed in Canada which you see at the bottom
but I don't have a lot of information in this particular one but it appears
that it does create a fair amount of soil disturbance.
The next technology that I would like to look at is briefly is the application of gypsum
and I'll mention this because it is promoted by number of scientists as a treatment
that can have some impact on reducing the loss of nutrients under no-till situations.
Gypsum has is primarily used as a source of calcium and sulfur,
but there are other potential benefits that's coming out of the research,
particularly ARS research and you'll see these listed here.
There's a number of different benefits, I guess the degree of those benefits would be
where a lot of people will say, "Well, maybe the benefit aren't all that great."
But there are also some incremental benefits that are provided including reduction
of aluminum toxicity, tie-up of soluble phosphorous, improved soil aggregation,
increased infiltration, and reduced run off and soil erosion.
As for the availability, gypsum is a naturally occurring mineral.
But most of the gypsum and the reason is really being pushed by a certain people at this point
in time is because there is an increased availability of gypsum at this point in time
as part of the treatment process to reduce some emissions of sulfur into the atmosphere.
A number of power plants have a large supply of gypsum as a byproduct and also in some areas
with a lot of construction; they have a lot of wall board maybe called by some of you
as sheetrock which basically is gypsum is the primary material within that.
And that is also being used as a byproduct for land application of gypsum.
So that is a treatment that I did want bring in.
It does have some values that are being proposed as the basis for recommending it for inclusion
in nutrient management under no-till situations.
And finally, when you look at actually managing the cropping system itself,
building organic matter and sustainability in the cropping system.
And you see that the things listed here there is eight different components
that I have listed here within a single cropping system, you may not include all of this
but this eight things, diversifying the crop rotation, minimizing soil disturbance
and maintaining the surface cover, maintaining live vegetative cover
when growing conditions allow, plant cover crops at times when feasible in the rotation,
use perennials as a base for a strong rotation, include a deep rooted species at least
in alternating years, include grazing animals to add vigor to the rotation, and applying manures,
compost, and other organic materials to supplement nutrients and stimulate soil biota..
These are things that can be used to build soil organic matter
and the sustainability in the cropping system.
If we look at the first graph, this is from some information
from the Morrow Plots at the University of Illinois.
Basically, you will see that the lowest soil organic matter
or the one that's depleting the soil organic--
the system depleting the soil organic matter the most is the continuous corn.
Those with-rotations are having less of an impact on soil organic matter.
There's a term, the rotation effect that is being used to describe of--
an observation that yields are usually 5 to 15 percent higher
in crop rotations than for continuous monoculture.
And this has been demonstrated in the same study at the Morrow Plots that the yields are higher--
significantly higher in crop-- when you have crop rotations
than you do when you have monocultures.
It's also been demonstrated at a number of-- a dozen or so other plot-- area--
research studies that that was able to locate from the Eastern United States.
But basically, if we have higher yields, then we'll return in biomass
and increase in the soil organic matter.
Also, a very important component of that diverse cropping systems to enhance organic matter
and stability in the cropping system is cover crops.
The cover crops alone, we can spend multiple webinars delving into cover crops
but I just want to point out those benefits that deal
with nutrient availability and/or the utilization of those nutrients
and reduction with loss pathways.
There are other benefits that are not included in this list that you see here,
but this list that you see here, fixation in nitrogen, increase in soil organic matter,
cycle nutrients, enhance nutrient availability, stimulating soil biota activity,
increase infiltration and reducing runoff, and also reducing soil compaction and rooting depth.
Certainly, these influence can help to minimize the loss of nutrients
and increase efficiency in nutrient utilization.
And this particular graph that you see.
This is from research from Dr. Ray Weil at the University of Maryland.
And basically, it shows the accumulation of nitrogen in various cover crops.
And note that the cover crops with the rye particularly have a significant capture
of nitrogen but not as high as the Brassicas that you see on the left and the big point
on that is the Brassicas have a lot of ability to capture nitrogen stored,
not only in the above ground plant material but also in the root system.
[ Pause ]
Cover crops do have a significant ability to take up soil nitrate and cycle nitrate
and reduce the movement of nitrate by leaching from the fields.
And this study from Ohio State University you'll note here that where there was a cover crop
of oilseed radishes that the soil nitrate levels was only about a third
of that where there was no cover.
In this particular graph you note on that cover crops also have an influence
on the solubility of nutrients within the soil.
And in this particular thing, this is also information from Dr. Ray Weil and he noted
that Brassicas appear to be particular adept at solubilizing phosphorus.
It's important to note that those Brassicas do not host mycorrhizae.
So this may explain the development of these particular species to exude this compound
that is organic acid exudates from the root that help to solubilize phosphorus
through the development of those species since they do not have a relationship or ability
to host mycorrhizae which would ask they bringing phosphorus to the root system,
this was another way that these species evolve in order for them to compensate
for inadequate phosphorus was actually by releasing those chemicals
to help release-- solubilize phosphorus.
In this particular study going back to nitrogen for just a moment,
this is a study by Dr. Tom Kaspar at the National Soil Tilth Lab.
And you note here the comparison for a number of years between situations
with the rye cover crops and the control.
And you'll note the dramatic reduction in nitrate levels and drainage water
for those fields where or those treatments where there was a rye cover crop as compared
with those where there was no cover crops.
That is also supported in a research project that was done
by Dr. Ray Weil at the University of Maryland.
In this particular study, he was looking at the ability
of radishes to capture nitrogen in the fall.
And you'll note that the treatments with the radishes, basically, you don't see the bulge
in the nitrate level as you-- we look down in soil profile for year 2003 or year 2002,
whereas in the control without the cover crop, you see this bulges,
these elevated levels of nitrates in the soil.
And finally, from Dr. Ray Weil, you see this on particular slide here which was from a chamber
that they actually were grow in canola in and then follow this up with soybeans later.
And you note the root the slide on the right-- left rather shows the canola root,
there was growing on May of 3rd or the void left are the canola root and then you'll see
on July the 7th, the soybean root and that same void.
So basically, a lot of these Brassicas and rye cover crops,
some of these species have fixed extensive root--
fairly extensive root systems for annuals at least.
And they have the potential to put in some macropores or some large void
within the soil there which allows the subsequent crop to develop a root system in.
There has been some studies that have been demonstrated
that cover crop has significant potential for reducing the movement of nitrates
and other nutrients by macropore or preferential flow.
Some scientists say that the water can still go down the side of the roots.
But still, the distance from the root
or that void is much smaller if it's plugged with the root.
So, there is a strong probability that the ability of roots
from the cover crop looking kind of inverse of this year,
if their cover crop roots are actually plugged in those pores that are left
by the previous crop roots, then those roots have significant potential to take
up those nutrients and also kind of plug those and slow down the loss of nutrients from a field
in which they which cover crops are present.
Roots tend to take the path of least resistance.
So plant roots and existing macropores may also partially contribute to reduce leach
and continuous no-till situations where cover crops are used.
And cover crops can also cycle nutrients in solution and take up soil water
that would otherwise transport nutrients.
This is from a study that was done by Dr. David Wright at University of Florida.
And in this particular study, he had two years of Bahia grass.
The first year which was harvested for hay, the second year was grazed,
the third year he planted peanuts, and the fourth year was in cotton.
This a system that Dr. Wright along with his colleagues have been promoting for use
in the Southeast There've been a few takers and farmers they've worked with in Florida, Georgia,
and South Carolina, and maybe Alabama, I'm not sure, but look at the benefits of this rotation,
you see it had a 50 to 100 percent increase in peanut yield, a 40-fold increase in crop roots
to 5 foot depths, an increase in cotton yields, reduction in pesticide nematodes,
reduced used of fungicides, nematicides and herbicides, increase in soil organic matter,
increase in water infiltration, and as an economic model based on this project.
They figured that the increase net profit for 200 acre farm from less
than 10,000 dollars per year to more than 40,000 with this particular system.
Now two components I would like to focus on for just a moment from this particular study
and the first date is the Bahia grass and the second one is the cattle.
Dr. Wright and his colleagues estimated or based on their measurement or the root mass
and from the Bahia grass in this particular study,
they estimated that the Bahia grass produced around 20 tons of roots.
So that's producing a lot of organic matter, adding a lot of organic matters to the system
where that is particularly important, particularly with the mineralization rates
down South, it could be important in adding-- building soil organic matter in any area
but certainly down South with the rates of mineralization.
That is very important to add that high rate of biomass to the cropping system.
And the second thing is the cattle.
Dr. Wright found that when they included cattle, they got a significant increases
in peanut yields versus where they hayed for both year's course.
If they hayed for both years, then they were taken out more biomass and more nutrients,
but one thing they figured out that was adding to it was that they increased the amount
of available nutrients within the surface layer.
But also, the cattle do trample in some organic matter
and also increased buildup of the soil organic matter too.
So a component of this has been found not only in this study but also by works done
in North Dakota and some other areas.
And finally, in closing, we open for any additional questions and comments,
but I would like to say as a final word here in terms of the presentation,
I encourage when looking at nutrient management in a no-till cropping situation
to manage the cropping system, not just the nutrients, think beyond just nutrients
and manage the whole cropping system.
In that way, we can really get increased nutrient neutralization in providing
for nutrient neutralization efficiency.
And also, minimizing a loss to these loss pathways.
>> Okay, thank you Gene.
That's an excellent presentation and I believe the system started
to work a little better towards the end.
So, we're open to some questions.
Now operator, if we got a few folks who want to call in
and open the lines up, can go that route.
And in the meantime, I did have a couple of comments
or questions come in that were written in.
This was kind of back to the use of manures and its impact or use on no-till.
The question is, is there any issue related to food safety with animal manure injections.
I guess the concern being it might leach down and it'll--
>> Well, there are issues with certain crops.
And particularly-- there's a root crops in particular, there are limitations in terms
of use of that animal manures related to production root crops.
For most other crops there would not be any actual limitations but there could be some
with certain crops where the animal manures could come in direct contact
with a commodity that's been harvested.
Those are already taken into account in the EPA and the FDA regulations.
I guess FDA would be part of that too, actually the regulations
for use of animal manures already.
>> Anyhow, a comment I'd add on that is this, the organic,
if someone has growing organic crops, they need to be very specific and follow the guidelines
as far as what's in National Organic Program--
>> That's right.
>> Second-- operator do we have any call in questions?
>> Thank you.
We will now begin the question and answer session.
If you'd like to ask a question from the phone lines, please press star 1.
Please unmute your phone and record your names clearly when prompted.
The name is required to introduce your question.
To withdraw your request, you may press star 2.
And it will be one moment for the first question please.
>> Okay, while we're waiting there, we got another question again
about solid animal manures, it says what suggestions might you have about management
of solid animal manures in no-till such as poultry litter and beef feedlot scrapings
in terms of timing and placement.
>> Enter-- to read some-- make sure I get the full gist of that Dave,
would you read that one more time?
[Laughter] Sorry.
>> Yeah, don't worry about-- okay, what suggestions do you have about management
of solid animal manures in no-till systems such as poultry litter and beef fedlot scrapings
in terms of timing and placement of these manures?
>> Well timing and placement would be a consideration in this particular
because of the fact with the solid waste then there's going to be a delay in release of a lot
of those nutrients 'cause they're going to be in organic form of course.
So, that would need be to be taken into consideration, I always want to follow
up the application of it with a live crop so that you could be cycling those nutrient.
Certainly, I mean, you don't want to have nutrients that are available for movement
about these loss pathways regards so you don't want to apply
in the fall litters or anything about that.
There's one thing I did may want to mention in as we look at the slide
with the solid waste application or the poultry litter application, I want to call attention
to the fact that poultry litter often more have a fairly has salt index
so that is something you also want to take into consideration.
The distance from the crop that relates to the question that was just asked in terms
of placement, you would not want to place the poultry litter too close to the crop
or you'd really want to analyze the potential for salt damage to the crop
because of the salt index of the poultry litter.
>> Okay, operator, do we have any questions?
>> Yes, we do have a question from Mark Scarpitti, your line is open sir.
>> Hey Mark.
>> Hi Gene, how are you doing?
>> Fine, how are you Mark?
>> Good. Hey, I know your thoughts on no-till are very positive
and use of cover crops came through loud and clear.
As, you know, in Ohio, you know, the soluble phosphorus problems that we're having
and it seems like a time after time, we get presentations from different university folks
that are similar to a lot of the studies that you showed
where they compare no-till to conventional till.
But the difference is the no-till is always surface-applied nutrients and they're comparing
that to-- on the conventional till to basically incorporated fertilizer.
And so, I think the driving force behind a lot
of that is actually the surface application of the fertilizer in their data.
Shouldn't when-- I mean if you're going to keep-- if you're going to truly look at no-till,
shouldn't the no-till-- the cropping system be separated
out from the method of application of fertilizer?
Shouldn't you keep those consistent in both ways-- in both--
shouldn't you keep the application of fertilizer consistent if you're really trying
to compare no-till to conventional tillage?
>> It definitely should Mark and that's a good point there or otherwise you're kind
of comparing apples and oranges and you have a lot of ability in there
if you don't separate out the tillage.
Now, one of the study that I cited that I believe it was from Kansas, they--
the impression I got in reading the article and--
they left with the research article was that they had--
that the data that I displayed was actually for surface-applied material,
both in the case of the no-till plots as well as the as the till plots.
They did have treatments though that were knifed in as well as surface-applied
and the ones were it was as a additional thing in the study.
Regardless of where it was no-tilled or where it was conventional tilled,
they found that they got at least a 50 percent reduction in loss of phosphorus
and surface runoff if it was knifed in rather than just being surface-applied.
Another thing Mark the comment that I make regarding adaptive nutrient management
and that was basically the reduction and the recommended rates of phosphorus
that they were now had for no-till corn or continuous no-till and today's discussion is
of continuous no-till, not as I said rotations were you have one year conventional
and one year no-till.
But in the situation that the-- in Maryland,
they had significantly reduced their recommended rates of phosphorous for continuous no-till
as compared with conventional till and based on the study that was done there that showed
that there, they didn't need the high applications of phosphorous
in a continuous no-till situation because of the greater efficiency
and the greater utilization efficiency of the phosphorous.
And, that gets to the point as I made in the presentation, I really think that if we think
of adaptive nutrient management as being related to nitrogen,
but I think there is also some potential here in terms of phosphorous, particularly for a lot
of farmers that are kind of moved to new technologies fairly quickly.
I think there's a lot of potential for them to significantly cut phosphorous levels maybe
with adaptive nutrient management on farm trials
and adjust their phosphorous application raise accordingly.
>> Thanks Gene.
>> Anymore questions operator?
>> Not so many further questions from the phone lines.
>> Okay, we got one more question and then I'm going
to cut this off Gene 'cause I know it's been we're past time but question came in about
in areas in the country where animal manure are available without capabilities to incorporate,
are we losing a lot of nitrogen in the form of ammonia nitrate.
>> Yes, we are and have that potential to have-- to lose a lot by volatilization is--
that depends on the particular manure as to how much
of the nitrogen is in the ammonium component.
So, that varies from depending on the manure itself,
but that is certainly a significant loss.
One thing and David would like to make a note that I know there was a lot
of fairly-detailed material here, so if there are any additional questions anybody has,
if they would send those to you or whatever, we certainly provide responses to those later on.
>> Okay, Gene.
Again, I appreciate your effort a lot of time and effort when in and out a lot of knowledge.
As a way of closing, I want to remind folks about two upcoming webinars in the month
of April, the next one on April 10th, Tuesday, that's our first in the organic series,
Understanding Organic Agriculture, Organic Pasture Management,
at Tuesday, April 10th, from 3 to 4 o'clock.
And then on April 25th, Common Bees and Best Bee Plants of the East with Dr. Nancy Adamson.
I did have a question related to the book I mentioned to begin with,
that was Building Better Soils for Better Crop Production.
It's a SARE Publication.
You can get a copy of it off the internet.
And one thing I failed to mention, if you go back up to where the handouts are,
I did post a copy of Managing Cover Crops Profitably
which is again another SARE Publication that you can download, have it on your computer,
it has more information about cover crops, and it's just a tremendous publication.
And the last thing before we sign off is just a reminder
where you can find a replay of today's presentation.
You can download it and there's also is a copy of the PowerPoint if you want to repeat this
and use it for your own use at the Science and Technology Training Library
and you see it displayed on your screen.
And with that Gene, again, I want to thank you for your effort, appreciate your tolerance,
this has been a little bit of a challenge but you're a real trooper.
And I just appreciate you being able to flow with the-- go with the flow.
And with that, we'll just sign off and say thank you and everybody have a good day.