[ Inaudible talking ]
>> I'm going to thank you all for standing by.
Participants will be in a listen only mode
until the question and answer session.
At that time if you'd like [background noise]
to ask a question please press star then one.
Today's call is being recorded.
If there are any objections you
may disconnect at this time.
I would now like to turn the
call over to Mr. David Lamm.
Sir, you may begin.
>> Thank you, and I want to welcome
everybody to the fourth webinar
in the Mississippi River Basin Healthy Watershed
Initiative where we're focusing on those things
that we can do to improve soil quality and
have a positive impact on the nutrient loading
that happens to be going
down the Mississippi River.
Today's topic we're going to be
talking about the role of soil biology
and improving soil quality and hopefully
you all have received a copy of an email
that has a little flyer like that in there.
And just for future references when you see
that you know there's a webinar coming up
and you can just say, "Click here" to join
the webinar, and that'll take you right in
and you walk through the walk
down the steps there and you ought
to be able to get into the webinar.
All of them are at 2 o'clock
Eastern Standard time on Wednesday.
Our next one will be on August the 10th.
We have made arrangements to get CCA,
continuing education units credits,
but it's up to you to apply for them.
What you have to do is go on right where --
just follow the red arrow over there on the top
of your screen, you should
see a hand out button.
If you mouse over that it should have
hand out show up and when you click
on it you'll get a screen that looks like
this that has a whole list of documents
that Dr. Nichols has provided
for you to download
that will help further your understanding of
soil biology and the work that she's been doing,
and the significance and the role that
it plays in improving soil quality
and nutrient availability and nutrient cycling.
Also you'll be able to click on there.
You need to check it, too.
Put a little check mark in there if
you want to download it, where it says,
"Documentation for certified crop advisors."
You click on that and you download that and
then you're responsible to put your name,
put your CCA number there, and then
sign it and you can get it back to here
at the East National Technology
Support Center in two different ways.
One, you can fax it and make sure you
put attention to Holli Kuykendall,
or you can scan that document after you sign it,
and email it to Holli.Kuykendall@gnb.usda.gov.
And you need to get that back within the next
two or three days so we can process these
and then what we do is basically we look at what
you send in, we link and provide the CCA folks
with a listing of printed -- those who have
participated that we get from the webinar folks
and they can verify that you
participated in the webinar.
If you want to ask questions
there's two ways you can do it.
We have all the folks are on mute right now, but
at the end of the session you can do it audibly.
You can press star, zero, and you'll get
the operator and she'll introduce you
and you can give her you -- your
name and then she'll bring you in,
allow you to ask your question that way.
Or the other thing you can do is, again,
at the top you have a menu list there,
you click on where it says Q and A,
that stands for questions and answers.
You just type in your question
and it'll go into a queue
and then we'll answer those as they come in.
So again, two ways one if you want to -- want
us to hear your voice, and the second one
if you want to type in a question.
That one might be kind of handy
as you're going through, you know,
Dr. Nichols will bring something up and
midway through the presentation you want
to remember it you can type your question
in at any point during the presentation,
but we will be only answering questions
at the completion of the presentation.
Now let me introduce Dr. Nichols.
I'm really excited about this
topic because I know all of us
out there meet the soil conservationist series
qualification and had a bunch of soils classes
when we were back in college and
we all learned about the physical,
chemical and biological aspects of soil but
somehow during our careers when we checked
out the soils class we left out the
biological part and we focus solely
on the chemical and the physical.
Throughout my career and the
way I was trained and brought
up in the Midwest the biological
aspect was never emphasized
and I think that's really been the key
to this whole issue of soil biology.
We're talking about increasing organic matter ,
understanding the important role the biology
the soil has in this and its significance
in maintaining sustainable soils
for sustainable agriculture.
Anyway Dr. Nichols was raised in Minnesota
basically on a corn, soy bean farm.
She received her Bachelor Science
Degree from the University of Minnesota.
So she's in the Big Ten there.
She got her Master's from West Virginia
University which shows how daring she is.
She was telling earlier how
she went there sight unseen
to get educated in microbiology out there.
She earned her PhD from the University of
Maryland and she's been on the cutting edge
of this whole idea of soil biology with the
a focus on mycorrhizal fungi relationships
with the plants and get involved
with investigations on farming land,
and you can read the rest, but I think we
have probably one of the leading speakers
on this topic that we could have got.
So I hope that you'll sit back and enjoy this.
And, Chris, I'm going to turn it over to you,
and we'll go up here and
bring up your presentation.
>> Thanks a lot, David, and thank you
all for attending and for the committee
for inviting me to give this presentation.
I'm really excited about having this
opportunity and I love to talk about soil,
so you may end up having to cut me off at
some point in time and just say, "Okay,
that's enough," because I could
talk about soil for hours,
and especially looking at soil biology.
I think David made a very good point in the
fact that a lot of times through our soil
of education we learn about the physical and
the chemical sides of soils and that's a lot
of the analysis that we do when we look at
soils, but often we don't look that much
at the soil biology and the
interaction that that has.
And so hopefully I'll give you some ideas on
the roles of some of the organisms that are
in the soil and what you can do to help manage
the system so that you're able to get more
of these organisms in your soil and what some
of those impacts are going
to have on the whole system.
When I was first asked to do this I sort
of started off and I was trying to focus
on the Mississippi River area
and then I realized that a lot
of these concepts are very general.
There are going to be some things
that I believe when you focus
on soil biology you may be adjusting or doing
some of the methods a little bit differently
or utilizing some different crops,
but the concept is the same.
It's going to work wherever you are.
A lot of times I've been in various areas
of the country talking to farmers and a lot
of times I'll say, "I hear all of these
excuses why your system doesn't work.
It's too cold, it's too hot,
it's too wet, it's too dry.
You know, it's never going
to be the perfect season."
As David said, I was raised on a
corn soybean farm and I told my dad
that if he ever had the perfect season
he'd probably die of a heart attack,
because it's never going to be perfect but
what we're trying to do is we're trying to come
up with a system that's going to
help you manage whatever it is
that you have, and whatever conditions occur.
When you focus on the soil biology you can see
by the huge diversity of numbers and diversity
of activity that you have a lot of redundancy of
function which means that whether it's too cold,
or too hot, or too dry, or too wet, there
are going to be some organisms in the soil
that are going to be working and they're going
to be able to provide some of these benefits
to the environment that you're
growing your plants in.
And so, you know, the quote on the bottom
I really believe in that civilization sort
of rests on the soil and they survive as long as
the soil is not exhausted, and we are, I think,
rapidly heading to a point where there's
going to be a lot of issues with the soil
and hopefully we can stop it so that
the soil is not completely exhausted,
because we need to maintain that resource.
I believe it's the most precious
resource we have.
We're talking a lot these days
about energy and things like that
and we can find other sources to produce energy.
We can find other sources to
alleviate some of the depletions
that we have in some of our resources.
But the soil resource is not a resource
that we can find alternatives for.
We can't find the alternatives that
are going to allow us to be able
to produce enough food to
feed our growing population.
So I just want to set the stage with that.
I reviewed a couple of the
earlier speakers and so a lot
of this information you probably
heard from some of the other speakers.
I'll try not to be too redundant but I'll also
emphasize again, some of the important topics
that exist out there with soil biology.
So to begin with I want you to think
of the soil as the heart of the system.
It basically is what's going to be connecting
above ground and the below ground activity.
So the organisms that are
above ground and the organisms
that are below ground are
connected via the soil environment.
It's also the ultimate recycler primarily
carbon and nitrogen and oxygen but other number
of different elements as well that is
necessary for the plants to be able to grow.
It drives the physical and the
chemical and the biological processes
that hold this system all together,
and it is estimated that the value
of the services provided by the soil that
includes soil life and its foundation.
Soils for building, soil for growing crops, the
biological activity, the organisms from soil is
over $20 trillion on a global basis per year.
But just the activity of the organisms
themselves in the soil, fixing nitrogen,
cycling phosphorus, providing
the nutrients to the plants
from that soil environment those
organisms are valuable extremely valuable
and if that's maybe their value can be
well over one and a half trillion dollars.
So we're looking at a resource that definitely
has a very strong economic value not just a
social and environmental value.
And the biggest part of the soil and
the thing that we can see the most
and identify what makes a good soil
versus a bad soil is that dark, rich,
organic matter that may be in the soil
and it's really a very small amount
of the total soil weight
but this is where almost all
of the functions that occur in the soil happen.
That organic matter is primarily negatively
charged, but it binds both cat ions and ions,
and if you can see from the figure below you
have this activity that's moving the nutrients
that are moving from soil colloids into the
soil solution and then into the plant root,
and a lot of that activity
is driven by the root exiting
which are feeding the organisms
that are in the soil.
So you have nutrients that bind
chemically with the soil minerals
but then you have mechanisms via soil
organisms to release those nutrients
and provide them for plant growth.
So as soil organic matter increases you can also
increase the amount of water holding capacity.
The organic matter like I said it's a very
small amount of the weight of the soil
but it's a large amount of the volume and
that volume versus weight allows it to act
like a sponge and it will
be able to absorb water.
And it's an area that stock piles a huge
amount of the amount of carbon that is actually
in the atmosphere of planet earth.
So it's this huge stock pile in the storage
of carbon and that carbon is very important.
This organic matter is very important
and the carbon in it is very important,
because it's the primary food
source either directly or indirectly
for most of the organisms in the soil.
And when you're looking at trying to grow
and maintain those organisms the two things I
want you to keep in mind for this presentation
and the things we're focusing on are the
basic needs of the organisms in the soil
and that the first basic need
just like any other organism
that these soil creatures have is food
and then the secondary need is habitat.
And so what we're trying to do is we're
trying to create an environment in the soil
that has the maximum amount of food and the
best habitat to maintain these organisms.
So we can start seeing the
functions increase and improve
in our soil systems and improve soil quality.
This is sort of a rough diagram of
again the concept of soil organic matter
and how much soil organic matter there is.
Again like I said soil organic matter
can be one to six percent of the amount
of the total soil mass and that organic matter
is primarily composed of the stable fraction --
the humid fraction that gives
that dark richness to the soil
and then you has the more readily decomposable,
the plant material those types of things
that are going to be in soil
environment and the smaller fraction
of that is actually the organisms themselves.
The bodies of the organisms are considered
part of the total soil organic matter.
The most dominant as far as weight is
concerned organism is the soil fungi
and then the most dominant as far as the number
of individual organisms is
actually the bacteria.
So in this case we're also looking
at parameters that involve size.
So the reason that the amounts are
divided up the way they are is not just
because of the numbers of the
organisms, but also how big they are.
So you may have very few animals in the soil
the micro arthropods and algae and protozoa
and organisms like that but they
actually can make up quite a bit
of the soil mass because of their large size.
[ Silence ]
Now in looking at the soil rhizosphere, this is
the zone that is right around the plant roots
and I think that we're going to see more and
more that basically, I'd sort of phrase it
as this that the root of the
problem is the root of the solution.
If we have soil roots in our environment
it's going to solve the problems that we have
in production in agriculture and a lot
of times we look at various problems
and we're actually not looking at the problem.
So we call them problems but they're
actually symptoms of a greater problem,
and that greater problem is a lack of carbon
and a lack of microbial activity in the soil.
Most of the carbon that's made by the
plant during the growing season is actually
transmitted into the roots and then out into
the soil to feed those organisms that are going
to be living around the rhizosphere.
So having a living root growing
in that environment can have a really big
impact on the soil environment itself.
It impacts the soil structure, it
impacts nutrient cycling activity
and this environment is where those
organisms are directly connected
with above ground management.
So even though these tiny
organisms may not have any contact
with the soil surface they are
definitely impacted by that environment
through how we manage systems and how
that impacts the roots and the amount
of carbon that's given to the soil
environment through the roots.
The soil livestock is very diverse
- it's a very integrated system.
It's a mixture of microscopic organisms.
You have molds and gophers and earthworms and
spiders and beetles and all of those types
of things that we're able to
see, and then you have all
of the microorganisms that are in the soil.
You have soil fungi and you can see sometimes
the representatives of fungi on the surface
in mushroom but those other organisms
that you have can be microscopic.
So it's very hard to see them and it's
very hard to think that they are present
in as high of numbers as they are.
It's said that in a handful of healthy soil
there are more organism than the number
of people that ever lived on planet earth.
So we have billions upon billions of
microorganisms in that soil environment
that are interacting with the environment
that they're living in but they're also acting
in such a way that they interact
with each other in a variety of ways.
It's going to allow for some of these processes
to occur and that's also very important
because a lot of times a particular type
of organism can't really
do its full activity alone.
It relies upon other organisms
to interact with it.
The biology of the soil is the organic
or living component of the soil.
That heart -- the soil is
the heart of the system.
What keeps that heart beating is
the activity of these organisms.
Again like I said there are billions of them and
they represent millions of different species.
The total weight of the amount
of organisms that are in the soil
in a cultivated soil you can get it down
to about five thousand pounds per acre
in a very healthy soil you can have four times
that amount, and its difficulty to be able to --
think one of the reasons why we don't always
look at the soil biology in our systems
in often times you can come up with standardized
tests that it's fairly easy to look at some
of the chemical interactions and some of the
physical interactions, but it's not so easy
to look at some of the biological interactions
because these organisms are so small.
You can have a very different community and
very different activity that's occurring
at one spot and, you know, different
activities that's occurring at another spot
and that's going to vary a lot depending
on the amount of water or nutrients
or physical properties of the soil.
You're going to have these micro
spaces in the soil environment
that may house one type of community.
It may be even though a lot of the
soil surrounding it is very dry
and the micro environment that's
created that is fairly wet.
And so it houses a different community then some
of the other environments that are in the soil.
So a lot of times when I'm doing soil
sampling one of the problems that I run
into from a research stand point is the
fact that I'll take samples in a thirty
by sixty foot plot which is about
the smallest plot that can be set up.
So I'll be taking samples from that plot
and I'll take the samples across the plot
and what ends up happening is in one sample
-- I'll take about 15 samples across the plot
and in sample number one I may hit upon a
large community of a particular organism
that I'm looking for and then in the sample two
or sample number three there
isn't that same large community.
So it's very hard to interpret exactly what's
happening when you can't get a very good count
on the number of organism
that are in that whole plot,
because there's so much variation
between samples.
And we're continuing to work from a
research stand point on finding ways --
better ways to sample and better
ways to analyze the samples
so that we can understand
that biology even more.
These organisms as I said there's a
lot of inter connection between them
because they can't do everything
by themselves and many of you --
possibly most of you have seen this graphic on
the soil food web, and the main thing I want
to point out with this graphic
is that the first tropic level
that first food source is
from photosynthetic activity.
It's from either the residue from the plants
or from the exits from the plant roots.
And so in order to be able to feed that
whole entire food web you need to have plants
that are growing or you need to
have a lot of residue in the system.
You need to incorporate something that's
going to be putting that photosynthetic carbon
into the soil as much as possible.
Again, kind of to give you a little bit
of an idea of what we're looking at here.
We're mostly going to be looking
at the microscopic organisms
which the largest ones are
one two hundredth of an inch.
The smallest ones are one
two thousands of an inch.
So we're looking at things that are very small
by comparison but again play a huge role one
by the numbers of them that are out there and
also, by the activity that those organisms do.
So now to kind of take a look at
those individual growths of organisms,
the bacteria can number in the billions in
soil and there's only about, you know --
there's only about 11,000 different species
that may be in a gram of cultivated soil.
When you're looking at a under
disturbed native type soil or --
you know, relatively high plant
production type of soil you can be looking
at over 500,000 species of
bacteria that may exist in there.
So there's a lot that happens above
ground that impacts the diversity
of these organisms that are below ground.
The bacteria primarily feed on organic matter
and it's the organic matter
that is easy to break down.
So it's some of the labile organic matter.
As they're consuming that organic
matter they're also converting a lot
of that organic matter into that humus fraction.
So you have some that the organisms
are going to take up but just again
like all organisms they take in food and they
give off waste, and you're also in this type
of a system you have both
predator and prey at the same time.
So we're going to talk about a lot of the
organisms that are actually going to feed off
of these other organisms and that are what's
going to allow for the cycling of nitrogen
and the cycling of carbon and
phosphorus and those types of activities
in that soil environment to have
that nutrient cycling occurring.
The bacteria can do some things in the soil
where they can help to decompose pesticides,
they can help to decompose some other chemicals
that are in the soil and break that down
and again they're very important
in the nitrogen cycle.
One of their important roles in the
nitrogen cycle is they act as a food source
for larger organisms and by being consumed
by larger organisms the nitrogen that's
in their bodies is released
into the soil environment.
You also have a lot of asymbiotic
and symbiotic bacteria
such as rhizobium there would be some added
bacteria that are associated with legumes
that actually can take atmospheric
nitrogen and convert it
to a plant available form of nitrogen.
So again they are very important in providing
the amount of nitrogen and that amount
of nitrogen is now become pretty close to the
amount of nitrogen that we fix synthetically,
and we're going to talk about what's been
happening with nitrogen use efficiency
and the need to keep producing more
synthetic nitrogen to feed our systems
and how that impacts grain production.
Now the fungi come in two main types.
They come in the saprophytic type
that feed on the organic matter
that it's more difficult to fight down.
There are actually more of
the residue decomposers
and that is an extremely
important role in our systems
because otherwise we basically would be buried
in residue if we didn't have these Saprophytes
but the organism that I spend a lot
of time looking at and that I see
that play a really important role in
our agricultural systems when you look
at nutrient cycling are the mutualistic fungi.
Primarily they're trading phosphorus for
photosynthetic carbon but they are able
to trade a number of different nutrients.
They can also act as assistance in some of
the biological cycles that are going on.
They can connect one plant to another
plant which can be very important
for nutrient flow and carbon flow in a system.
They also are very important to
the physical structure of the soil
to creating a stable soil environment
and one of the ways they do this
is by formation of soil aggregates.
The fungal hyphae will act like a net to
accumulate soil minerals and organic matter
and other organisms to form these
balls or pallets in the soil
that are the soil aggregates, and
the soil aggregates as we'll talk
about a little bit later as well, have a very
important role in what's happening in the soil
and how that impacts plant growth, as well as,
the various ecosystem services
that the soil provides.
But these organisms are, their bodies are
primarily these fine threads or strands
of fungal hyphae and those
threads are very fragile.
They're very easily harmed by plowing
or disturbance to the soil environment
and for the mutualistic fungi they need to
maintain that connection with the living plant
because they aren't decomposers
like the saprophytic fungi.
So they can't find a new food source.
They need to be connected to a
living plant in order to be able
to get their food and grow and survive.
The mutualistic fungi the primary group
of mutualistic fungi are the
vesicular mycorrhizal fungi,
and literally that means arbor,
like Arbor Day, it's tree shaped --
so they're tree shaped and mycorrhizal
means myco is fungus and rhiza is for root.
So they're tree shaped fungal root fungi,
and what that means is they are very good
if you look at the picture you're
able to see how the fungal hyphae goes
out into the soil beyond that
depletion zone that the plant will have.
The plants are very good at taking up the
nutrients that are right next to the roots
or can come in contact with the root
hairs and they deplete the nutrients
that are there very readily, but then they need
a mechanism to grow out further into the soil
and this may only be one to
two inches out into the soil.
It doesn't seem like a lot but it actually
can make a very huge difference on the amount
of nutrients and the amount of
soil that the plant can access.
Again the fungal hyphae when they're growing
out into the soil they'll sort of branch
out into tree shaped like
structures, and what that allows --
it allows them to have a greater surface
area to volume ratio and basically what
that means is the fungal hyphae can
contact more soil with a smaller strand.
So there's less carbon that's needed to form the
small strands then there are the large strands
and so there's greater volume
that's in the large strand.
These fungi are generalists they will
colonize a number of different hosts.
They actually penetrate into the
root cell through the root cell wall
and then they'll form these other
branch structures and that allows them
to maximize the contact they have
with the plasma membrane and the cell,
and they can very easily then transfer
the nutrients via that contact.
So both of these mechanisms are allowing them
to maximize their activity for a minimum amount
of carbon use, and this is
why they're very important
to the plants that are growing in the system.
If you don't have a lot of these fungi in the
soil environment what we've seen is often times
that can stretch plants or it can require
the plants to need more synthetic nutrients
because this is the primary mechanism
that the plants evolved with over time
to acquire the nutrients in the soil.
If we take that away we have to replace
it with something and that's one
of the things that's happened in our ergonomic
systems and the way we manage them by again,
doing a lot of tillage in our systems
by having none complex rotations
so you may have corn soybean two
crop rotation or continuous corn
which is only a one crop rotation.
So you're not giving them a
lot of different kinds of food.
That's what a rotation does is it
provides some different kinds of foods
to feed these organisms again, because
they're connected directly to a living plant.
If there isn't a plant growing -- whenever
there isn't a plant growing you don't have these
mycorrhizal fungi growing.
So if you have fallow in your rotation system
which is common the further west that you go,
you're not going to have a lot of these fungi.
And again what they do is around that
rhizophere they're very good at making --
they engineer their own environment
that assists them
in maximizing the amount of
nutrients that they can get.
They've helped to form those soil aggregates
and in those soil aggregates
they attract different bacteria
and those bacteria will do some of the
activity to help to release phosphorus
from the soil mineral, they'll do
activity where they're fixing nitrogen
and that is providing those
nutrients that the fungi can then take
out and deliver back to the plant.
This is a pay as you go type system.
The plant will not give carbon to the fungus if
the fungus does not give nutrients to the plant
and again in our modern cultural systems what
we've done is we've given the plant a lot
of nutrients very early in the
growing season which puts a lot
of nutrients in that rhizosphere environment.
So the plants don't need to have the
relationship with the fungi at this time.
And so they'll basically not give carbon to
the fungi and eventually the fungi will start
to die off and they'll give up on being
able to get carbon from the plant,
and that's what's reducing the numbers of these
fungi in the system in addition with the levels
of disturbance and the amount
of plant growth that we have.
So all of these factors that we're doing through
background management are impacting how much
of this fungal growth we can actually get and
how efficient our systems are actually being.
This is some microscope pictures so you
can get a real visual representation
of what's happening.
The top picture at the top -- left hand
picture shows the fungal hyphae extending
out of the corn roots and you can see all of
those really fine threads that are out there
and it basically can -- if you look at
the amount of carbon that was in the roots
and the amount of carbon that's in that fungal
hyphae, you can double or triple the amount
of access that you have to the soil, but
you're only doing that at maybe a half
to a quarter of the amount of carbon.
So again, it's a very efficient way of working
in a system and the left right hand picture --
or the right hand lower picture shows the
our vascular that are inside the roots
and as you get more of that tree shaped or
bushy structure the more you have in contact --
more hyphae you have in contact with the plasma
membrane of the root cell that allows you
to have this very efficient type of exchange.
So again these organisms evolved
with the first land plants.
For plants to be able to grow on land and
get the water and nutrients they needed,
they needed to be associated with these fungi.
There's strong evidence of
this in the fossil record.
They were able to see that these
plants did really utilize the roots.
In fact the first land plants utilized the
roots primarily for a anchoring structure
so that they could start to grow up as opposed
-- and get into larger sizes as opposed to,
algae that are in aquatic systems
that they originally evolved
from which are mostly unicellular.
So they're now able to become multi cellular
organisms and grow up because they're anchored
in a spot but anchored in a spot makes
it harder for you to get nutrients.
And so they had to form this
relationship in order to be able
to get the nutrients they needed from the soil.
[ Silence ]
The next organisms we're going to
take a look at are the Nematodes.
And I wanted to bring up the nematodes
because nematodes generally get a bad rap.
They're mostly considered
bad, they're pathogenic.
They're horrible to have in your system.
You have to put in pesticides and exterminate
them as much as possible from the system.
Most of the nematode species
are actually none pathogenic.
They're organisms that actually
primarily feed on fungi and bacteria
and that can be very important
because they're very good at helping
to control the populations of some organisms.
The idea of the diversity of these organisms
like I said you can be both predator and prey
at the same time, and by being prey it
means that there's one organism that helps
to keep your population in check.
The reason that we have a lot of
diseases in our modern cultural systems is
because we're growing primarily one type
of plant that is supporting the life
of very particular types of organisms in
the soil and those numbers of organisms
because they're the only ones getting
fed their population grows out of control
but if you maintain the diversity of the system
those different organisms are going to make sure
that one population doesn't go out of control.
It's very important to have these organisms
and by consuming the bacteria they're able
to consume the bacteria in very large
numbers and so it's very easy for them
to release some nitrogen from the system because
the nitrogen again that's locked up in the body
of the bacteria the bacteria is consumed by
the nematodes and some of that nitrogen comes
out of the nematode as waste and then that
nitrogen when it comes out of the nematode is
in a plant available form
because it's been broken down.
So it's an inorganic form instead of the
organic form that it was in when it was a part
of the body and when it's in that inorganic
form it now can be taken up by the plant.
So it's a way of cycling nitrogen to the system.
It goes from an inorganic form into the bodies
of the bacteria and then bacteria are consumed
and it's released from the bacteria into
an inorganic form and that can go back
out to the plant and we can reorder it into
an organic form again and keep on going
through the cycle unlike the bacteria where
you have billions of them in a gram of soil
for the nematode you may have
only ten to twenty individuals,
but again, their size is much large.
So they're able to those ten to twenty
individuals can represent about ten percent
of the microbial bio mass whereas bacteria will
represent about 30% of the microbial biomass.
So in a lot of the cases the organisms below
ground size and numbers matter and you want
to make sure that if you're small in
size you have a very large number,
so that you can actually
impact the entire system.
The picture that's at the bottom
is one that I like to show
because it's actually a fungus
that is trapping a nematode.
The fungal hyphae those threads that are the
body of the fungi it forms a loop or a lasso,
and then it will give off some
compounds that will attract the nematode.
That basically it's telling the nematode there's
food there and the nematode will come toward it
and when it wiggles its way into that lasso
the fungi will actually cause cytoplasm to get
into the cells that are making up
that lasso and those cells will swell
and then it traps the nematode there
and then the fungi will release
enzymes that decompose that nematode.
This is a way of the predator and prey
relationship and only do you have the nematodes
that can still the fungi and the
bacteria to keep their numbers in check,
but you also have fungi that can consume
nematodes to keep their numbers in check.
So again, you have less pathogenic type of
relationships in a healthy soil then you do
in a non-healthy soil and it's because of
all of this activity of these organisms.
They're helping to keep populations
under control.
[ Silence ]
The last microorganism, I'm not
going to discuss some of the Mezzo
and the Macro organisms very much in the
system because I want to focus in on some
of these very small organisms that we
don't see very much and we don't pay a lot
of attention to, but for the last minutes
I'm going to focus on the Protozoa
and they include a wide diversity
of types of organisms many of them
that you've probably seen or heard about.
You have the Paramecium, you have Amoebas.
They basically move by flowing their
cellular contents from one part of their body
to the other part of their body, so
that they can move through small spaces
and actually move in the soil environment.
Most of the ciliates and the flagellates
actually have hairs that help them to move.
The organism that's in the upper right
is sort of a cross between the two.
It has cilia and you can see their fuzzy on the
front part of the organism but mouth parts are
and that cilia what that does is --
instead of helping the organism to
move it actually causes bacteria
to flow towards the mouth of this
particular protozoa so it makes sure
that it gets its food source flowing to it
but it actually moves more like an amoeba.
It moves by moving its cellular
contents or it's called pseudopodia.
They stick out part of their body
like a leg or an arm and move that
and that allows them to move forward.
It's an anchor that they can move
the rest of the body too and again
like the nematode the protozoa are larger
in size so there's fewer in number in a gram
of soil and they consume the bacteria.
So again they're an important part of the
nitrogen cycle because they're eating bacteria
and pooping out nitrogen in a plant available
form in an inorganic form when they break
down the bodies of those bacteria.
Oh sorry I have one more group I apologize.
One more group the Micro Arthropods
and these are the microscopic insects
and they are the decomposers and the shredders.
They're very good at breaking large pieces
of organic matter down into smaller pieces
that then the bacteria can consume.
In an agricultural system they are very easily
harmed by tillage practices and pesticides.
The insecticides that utilize
inter ergonomic systems
to control large macroscopic insects also affect
these micro arthropods these microscopic insects
which means that every time you spray an
insecticide not only are you getting rid of all
of the larger macroscopic insects whether
they are good or bad you're also getting rid
of the micro arthropods whether they are good
or bad and that can affect the amount of food
that the bacteria can have because there's
nobody to shred that organic matter
into the small pieces that bacteria can eat.
So organic matter decomposition relies more on
the activity of saprophytic fungi then it does
on this combination of micro
arthropods and bacteria.
So now you're limiting those
various populations as well
and this gives you a relative size of things.
So we've got a thin particle
and then you've got one
of these micro arthropods these microscopic
mice that's the biggest thing on the picture
and then you can hardly see
the nematode that's there.
That's a microscopic worm.
From a scale standpoint if you were looking
at bacteria you basically would see the --
instead of a mite it would be a
nematode that would be that size
and then the bacteria would be something
you could barely see on the screen.
So [background noise] again, there's a huge
variation in size in these microscopic organisms
but they all play some different
roles in helping that system work.
There's also earthworms that are in the system
and this is the only macroscopic organism
that I'm going to talk about and the reason
I'm bringing out earthworms is they form
and you can see it in the lower right hand
corner they form these tunnels in the soil
and they leave behind surfaces soil cast that
contain a huge amount of nitrogen and phosphorus
and organic matter and that helps
to feed some of the other organisms.
In fact along that tunnel that is growing
through the soil you'll have bacteria
that will just line the surface of that
tunnel, because as the earthworm grows
through the soil it leaves behind --
on the surface of the body it has
some lubricating polysaccharides.
It leaves behind those polysaccharides which
then becomes food source for bacteria and fungi.
So it's a way of the fungi and the
bacteria getting deeper into the soil
and having a continuous amount of food source
because they can't travel very
far given their limited size.
So the bottom line with what you want to do the
first thing that you really want to focus in on
for the system is to replace iron tillage
with biological tillage with
the activity of earthworms.
Replace it with the activity
of plant roots that are --
you have some large tap roots that can
help break up layers of compaction.
The fine roots that will come from grass
plants that will spread out in further
in the soil and create smaller channel.
But they're still creating tunnels and reducing
compaction in soil environment and I see
as the primary thing to do even though the
greatest need that a plant has is for food
because a lot of times if you have a lot of
compaction and you have an iron tilled system --
a conventionally tilled system you'll
have layers of compaction that are right
under that soil layer and that means
that you can't get the plant roots
and you can get those organisms to grow with
the plant roots very far in the soil environment
and so you aren't really being able to support
a lot of good diversity of organism growth.
They may have food because you have a plant
growing but their habitat is so disturbed
and so broken up that it's hard for those
organisms to even try and survive and to be able
to get to many of those food sources.
So again what you want to do is you want to
build the amount of organisms that you have
in the soil and I want you to do
cultivation but I don't want you
to do cultivation with a
piece of metal equipment.
What you do cultivation with is you cultivate
those organisms so they will do that cultivation
of the soil environment themselves and
again what they need primarily is food.
They need to have a diverse crop rotation.
So you're feeding a different
type of food source.
This is basically giving the soil environment
proteins and fruits and vegetables and bread.
All of those things that the different organisms
need to grow you're providing that into
that environment when you have a more
diverse crop rotation and if you're
in a system you're working with producers
that are in a system that because of equipment
and because of marketing needs they fixed
them better to have a shorter rotation.
There are alternatives to improving that crop
rotation by adding cover crops or switching it
up a little bit where maybe you'll
grow a cover crop for part of the year
or you'll grow a hay crop for part of the year
so that you've got something different that's
in that system that helps
to provide that diversity.
You want to make sure that
that food source is consistent.
The last thing you need are these organisms
starving and Jim Hoorman brought up this topic.
He was talking about the fact that these
organisms even here in North Dakota
which many people consider the end of the
earth and a frozen wonder land even here
in North Dakota we can have microbial activity
happening almost every day of the year and I say
that because we've done studies
where we've looked at gas emission,
we've looked at CO2 emission,
and nitrous oxide emission.
Gases that are produced by organisms
that are growing in a soil environment
and we can measure those
almost every day of the year.
So we're able to see the fact
that organisms are growing,
and part of that is those microorganisms
are creating those micro sites.
They're creating that little environment that
they need to be able to continue growing.
They'll create the stable those
aggregates that are part of their habitat.
They engineer their own homes in order
to keep themselves in an environment
where they can maximize the amount
of food that's available to them.
They can protect themselves; the bacteria
that are in these environments are protected
from the nematodes and the micro arthropods
and the protozoa so they're not consumed
at the same rate, and they're in an aggregate
where there's organic matter available
to them that's locked inside that
aggregate that they can consume
and that aggregate again is a protected
environment where a lot of the changes
in temperature and changes in moisture
that's the last places they'll get
to is inside that aggregate.
So you can have more stable temperatures and
more stable water conditions moisture conditions
to maintain that activity for a longer period
of time and what we do with a lot of our systems
when we don't include cover
crops or perennial --
something that gives continuous cover what
happens is we're basically feeding the organism
for short time -- if you're growing a short
season grass like wheat for about two months
of the year and expecting
those organisms to survive
until the next year when you're planting.
So we're feeding billions of creatures on
about two months of carbon and expecting them
to survive for ten months and it's a system that
over time doesn't work because you're continuing
to deplete the number of organisms
that you have in your soil and again
if you cultivate these organisms
you're going to increase the amount
of soil organic matter you have, you're
going to improve the fertility of the system
because you're going to have better nutrients
linked through all of these different types
of organisms and in the long run will
increase the profitability for the producer
because there's less synthetic nutrients they
need to add, less pesticides they need to add,
less maintenance and cost in creating a
none compacted and growing environment
for the plant roots to be able to
grow so you can get higher yield
and you're also creating an environment
where you have less top soil loss to erosion,
whether it's wind or water erosion.
So you're creating a system
that is automatically going
to be more profitable to the produce.
In the beginning in creating
a lot of these systems
and making these system changes you
may end up seeing yield decline.
It's very common as the system
is transitioning from a system
that wasn't very biologically active to
a system that's very biologically active
but at the same time you're reducing costs and
so a lot of times when you're I guess trying
to sell these management changes to producers --
when I'm talking to producers a lot of times
it's not just about what you make at the end
of the year when you sell your grain but
it's about what your overall expenses were.
Your overall net profit was and that's
what's going to be important in making sure
that people utilize these systems because
you can reduce some of these costs.
Reduce the amount of passes that you
have over the field and reduce the amount
of diesel fuel you use and like I said you
reduce the cost of pesticides and the cost
of some of the synthetic nutrients and from an
environmental standpoint you also get long term
sustainability of the system.
The way that we utilize a lot
of our agricultural systems right now
we do different mechanisms in order
to try and make them sustainable.
We do terracing, we've done sustainable tillage.
We try and grow more crops.
We try and increase plant population.
All of these things that we're trying to
do to help create a more sustainable system
but at the same time a number of the things that
we're trying to do are actually not contributing
to long term sustainability of the system.
It's a very short term impact and what we
need to do is introduce all of these tools
to create a system that's
biologically active and going to be able
to provide these benefits
and this is just a long list.
I'm not going to go through because we're going
to touch on a lot of this stuff and have touched
on a lot of this stuff but these are the things
as you can see there's a huge amount of things
that just putting carbon into that
rhizosphere, increasing the amount root exudates
that you have can have on the health of the
entire system and sustainability of the system
and when you do these things where
you're changing the tillage type
and you're changing the plant diversity,
adding these various components
and you don't have to add them all.
Just as you're adding some of these
various components what you see is
that the math doesn't work anymore.
Two plus two does not equal four.
You can have two plus two equaling sixteen
because the effects are not adding they're
multiplying each other and so you want
to be able to create these management
systems that are actually going
to give more then they're going to take away and
that's working with the background management
and reducing the amount of tillage.
Adding some crop diversity, adding
cover crops, adding manure and compost,
working with the timing in which you make
these changes, adding grazing as a way
of managing some of the forage that you have,
some of the crop residues that you have,
making sure you maintain some
crop residue in the environment.
All of these different things are going
to have huge benefits to the system.
When you do tillage I talked about this with the
fungal hyphae and this illustrates what happens.
So you do tillage and it breaks up the fungal
hyphae and it's in strands and it exposes
that humus organic matter to the surface
and what that humus organic matter is
on the surface it's actually
exposed to the decomposing organism
and so it basically can get eaten up very fast
because the decomposing organisms what they do
is they eat high carbon, low nitrogen material
and they eat it fast and the reason they
do is because often times the protein
or what contains the most nitrogen is taken off
of the field as the crop that you're growing
as the grain that you're growing and the residue
that's left behind is very high in carbon
and low in nitrogen and that's very
similar to that buried organic matter
that humid organic matter
in molecular structure.
And so those decomposers that need to
eat it fast so that there's not residue
that is increasing on the top of the soil
so that you're getting some residue
decomposition they eat it very fast
and they'll eat the organic matter as well
and then that just ends up getting burned off
into the atmosphere as CO2 and we've
seen evidence of that as we've looked
at the historic loss of soil carbon.
So as we're looking at when
we started applying tillage
to the soil system we rapidly reduced
the amount of carbon that was in the soil
and we're trying to change some of that.
you can see starting around the
1970s when we had the oil crisis
and then we had the clean air act put
into position and the clean water act put
in position those changed some
of the ways that we manage
but that actually hasn't had a
dramatic increase on the amount
of carbon that we have in the system.
So we want to increase that amount of soil
carbon because we can see all the benefits
that come with water holding capacity and food
from microbes and all of those different things
that come with having more
organic matter in your system.
So we want to continue with this idea
of reducing tillage but we also want
to find some other mechanisms that may allow us
to increase the amount of organic matter we have
in our soil at an even faster rate and
one of those is by adding crop residue
and there's a lot of question as
to if residue is treasure or trash,
if it should be just taken off and
maybe utilized as a biomass fuel source.
And you know there are issues
with it for feeding.
There are issues with it for carrying disease,
all of these different types of things
that we think we that don't want
to have a lot of crop residue.
In corn cropping system they
actually add a lot of nitrogen
to help decompose that residue at a faster rate.
But why would you want to do that?
Because the residue is protection for
the soil, it is providing some nutrients
to the growing plant as some
of that residue is decomposed.
It's providing more organic matter and much
more food to the organisms that are below ground
that allow for those organisms to grow
and provide all those benefits
we talked about before.
So maintaining residue can be one way to
couple with tillage that's going to help
to improve the amount of
carbonate we have in our system.
Plant diversity is also going to help with
the amount of carbonate we have in our system.
And you'd think if you added a lot
of cereals, which have a high carbon
to nitrogen ratio meaning for every atom of
nitrogen there are 80 to 100 atoms of carbon.
And you would think that that would be good
because the more carbon you have the
more organic matter you have, right?
Well, that's not really the case because
again when you have that high carbon
to nitrogen ratio, the things that are
decomposing that are very fast growing.
They let most of that carbon go back into the
atmosphere as CO2 and the nitrogen is consumed
in that decomposition of that carbon.
So you don't end up building a whole lot
in that system, but if you add things
like legumes they're going to increase the
amount of nitrogen that you have in the soil
and they're going to improve
that system so we can get better,
we can get closer to what the average
is for soil organic matter itself,
closer to that 10 to 1 or 12
to 1 type of organic matter.
But we're better able to build
up that instead of consuming all
of the nutrients and trying to decompose that.
The cover crops are a thing that
we're discussing more and more often
as possible mechanisms to improve the system.
And one of the things that the cover crops
is doing is it's continuing the amount
of living plants that are growing in the
environment and when you continue the amount
of living plants that are growing
in the environment you're getting
more carbon exuded absolutes.
You're building up that organic
matter in your system.
You're providing more for the mycorrhizal fungi
to the mutualistic fungi to be able to grow
because they're directly connected to
the plant and from the mutualistic fungi;
they're giving off carbon to bacteria.
They're providing a food source
for some of the larger organisms
in the soil, the nematodes and protozoa.
So it's a very good way of being able
to get more carbon cycling through
and feeding these different organisms.
And that's going to help overall in building
up the amount of carbon that you have.
I want to kind of point out these pictures.
The top one was actually from my
dad's farm in southwestern Minnesota.
He does sustainable tillage.
He's not into no till.
And, you know, corn -- soy beans -- he's
now converted mostly to corn in his system.
Corn and wheat actually, he's kind
of changed up in the last two years.
But what he's done is last fall he came up
here to North Dakota and he heard a number
of producers talking about
the benefits of cover crops.
So he put in a cover crop into his system.
And then this spring, he burned off the cover
crop that regrew even in Minnesota again
where it gets fairly cold over the winter.
He did have cover crop that he
planted last fall and that regrew.
He planted it about August 20th and that regrew
in the spring, and he had clover and radishes
and turnips in his system,
in his cover crop mix.
And so he had a lot of clover this spring
and a little bit of turnips growing, as well.
And then he planted it -- he burned
it down and he planted it to corn.
And this is on June 19th.
It's about -- not quite a month, after he
planted the corn but the corn is coming
up through the stubble that he had left behind.
It was a very cold spring, so you
wouldn't expect it to be very high,
but it still shows you that you can add
some of these things to your system.
And it's going to be able to
continue what you want to have happen
with your cash crops in your system.
There are mechanisms to do it.
There are plant choices that you can make.
There's timing choices that you can make.
There's, you know, cash crop choices.
There's also cover crop choices that you can
make that are going to help make this work.
The bottom picture is actually a very
interesting producer from Emporia,
Kansas and this is his corn
crop, which was planted in June
after he harvested a winter wheat crop.
And then with the corn crop, he put in a
cool-season cover crop mixture so it would grow
as an understory crop with that corn crop.
And some of those plants are going to survive
in the shade under that corn crop and be able
to grow into the fall after
he harvests the corn.
So he's maintaining that
living cover as long as he can.
And that's, again, one of the biggest
keys about improving the system.
Again, you have lots of different cover
crop choices and the plants that you choose,
warm season and cool season,
legumes, and grasses, and oil seeds.
Just a tremendous amount of choices that you
can make in order to tailor that cover crop
for what it is that you need to tailor it for.
This is a picture you probably have seen before.
This is up here in North Dakota in 2006.
We had a total, where this field was
at, a total of 7 inches of soil moisture
and where they planted one cover -- one
species of cover crop, the crop died.
It was very dry obviously
and it was a pretty hot year.
Where they had the cocktail mix it
included both turnips and oil-seed radish.
They had a mixture of that with a number
of different crops and that crop thrived.
These pictures were all taken on the same day.
[ Silence ]
>> Now, one of the reasons that that can work
is that you can get these things where, again,
the effects are multiplying
instead of just adding together.
So if you add no till and
crop residue, and then you --
you can also add a cover crop so you've
got living plants that are growing,
you're definitely going to have a lot less
weed pressure because the seeds are not going
to be able to germinate very well because
they're not going to get a lot of sunlight.
There's poor seed-to-soil contact and the
seeds with the no-till system are left unburied
as opposed to when you till you
basically are burying weed seeds.
If you are able to get this system where
you're getting an increase in weed control
without having to use any type of pesticides
to do that, this is where I'm talking
about fertilizer use, especially
nitrogen, which are the blue diamonds.
There's been a huge increase in
the amount of nitrogen that --
that we're using in the United
States in the last about 50 years.
There's not been a whole lot of change in
the amount of phosphorus and not much change
in the amount of pot ash, but
focusing really on the nitrogen
in the system you can see this was
done in Illinois at the Morrow Plot.
And they were measuring potentially
mineralizable nitrogen so the amount of nitrogen
that can become plant available
and what they found is
over time they had a continuous corn treatment.
They had corn and oats.
The oats were replaced with soy beans in '67
and they had a corn-oat-hay type of system.
And they applied nitrogen synthetically
as was applicable to the particular crop.
And you know, most of that
had been the same since 1967.
Some of it since 1955, but what they
found is that between 1955 and 2005,
they would have a drop obviously, in the
amount of potentially mineralizable nitrogen;
the amount of nitrogen that you could get
that would feed your plant even though
the fertilizer rate was the same.
There was this drop in the amount
of nitrogen that was available.
Something's happening in
our systems that, again,
is making that nitrogen use sufficiency decline.
And this was done up in Canada and what they
found is that the longer they had no-till
in the system the more their production didn't
change even if they added more nitrogen.
So if you were in a conventional system or
transitioning out of a conventional system,
you needed a lot more nitrogen to try and get
very similar yields, instead of being able
to maintain the yield with very low
amounts of nitrogen and utilizing
that nitrogen that's in the soil system.
We're seeing that this graph is, again,
showing on the left-hand side the cereal yields
over time and that seems to be
following fairly closely the amount
of nitrogen that we've applied.
It's the same shape of graph, but when you
actually look at nitrogen use efficiency,
so what you are really getting back over time
in yield compared to the amount of nitrogen
that you're adding, you're
actually seeing a declining curve.
So that's looking at, you know, it's
not looking at grain yield increasing
because of changes we've made in
management or nitrogen use increasing
because we're increasing the amount
of nitrogen, but how those --
when you put those graphs together
how they actually look together.
And even though you'd think that they, you know,
look fairly the same it would be an inclining
curve, it's actually a declining curve.
We're seeing that when there's
more fertility added to the system,
there's not necessarily more yield.
And a lot of that has to do with the timing
and the availability and when you work
with the organisms in the soil, they're
actually going to change the amount
of nitrogen that's available
and when it's available.
You'll get these things where
you get interplant transfer.
You'll have -- you have basically a corn
plant and legume plant growing side by side.
And in the rooting environment you have fungal
hyphae that's connecting those two plants
together and you have rhizobium
bacteria that are fixing nitrogen,
and that rhizobium bacteria is fixed
nitrogen, it takes a lot of energy just
like it takes to make synthetic nitrogen.
And that energy comes from
the cellular powerhouse,
which is powered by the amount of ATP.
You basically take this molecule called
ATP and you break off the phosphorus
and that releases electrons
to help fire the energy
for the different processes in the cell to work.
And when you do this, you actually need an
influx of phosphorus to convert that ATP --
that ADP -- it goes from ATP, which
adenosine triphosphate to ADP,
which is adenosine diphosphate and to put it
back to ATP, you need an influx of phosphorus.
When the mycorrhizal fungi are associated
in particular with a grass plant,
they have better mechanisms, even better than
their natural mechanisms to acquire phosphorus.
They work with bacteria that are actually in
the fungal hyphae that colonize the surface
of the fungal hyphae and those bacteria
solubilize phosphorus for minerals.
It's a way for them to get more phosphorus.
Having them associated with a grass plant
stimulates the amount of activity that occurs
and the amount of phosphorus that's acquired.
So the fungus will take some of the
phosphorus that it acquired for the grass
and it will transfer it to the legume so
the legume can transfer it to the rhizobium.
The rhizobium can fix more nitrogen and
then the fungus will take that nitrogen
and transfer it back to the grass plant.
And we're really seeing this effect happen
when we have these cover crop cocktails,
crops that are growing at the same time.
So, again, we're getting
improvement in the cycling of nitrogen
when we have cover crops in the system.
We're now going to try and improve that nitrogen
efficiency because now that we have improvements
in the amount of nitrogen that can be fixed
and the way the nitrogen can be transferred
between the plants, it allows us to use a
lot less fertilizer because it's providing --
that nitrogen fixation is providing a continuous
nitrogen source to both plants in the system
and then their residue is going to have
more nitrogen in it and you've got a legume
that has a higher amount of nitrogen
compared to the amount of carbon that it has.
So it's able to actually get more nitrogen
and the residue was able to get more nitrogen
in the roots to be able to feed these
organisms in the soil, but also to be able
to create nitrogen for the
subsequent plants to be able to use.
We have to use less fertilizer
to do it and that's what's going
to improve our nitrogen use efficiency.
The cover crops, again, can augment the
amount of soil cover that you have and even
when you just have residue on the soil, you're
not able to cover as much as the soil surface
as you would by the shading
of leaves of different sizes.
So when you have a cover crop that has a
mixture of different plants that have a number
of different leaf sizes and leaf heights,
you're able to better cover that soil surface.
And you're able to -- this was, again,
done in North Dakota on those fields
that the previous picture with the
dead radishes and the dead turnips,
and the living cover crop mixture.
You're seeing about a 20-degree temperature
difference between having that cover
and having just some residue that made it
through the winter and spring on that soil.
And that makes a huge difference in
the amount of microbes that you get.
Optimized microbial growth occurs
at about 80 to 100 degrees.
It starts slowing when you start going
above 100 and as you get from about 115
to about 130, it basically stops.
It kills off all of the microbes.
So the previous slide, at those temperatures,
what you're getting is you're getting optimal
microbial growth in a field with cover plants --
cover crop plants and you're getting a
slow-down and almost a death of microbial growth
when you've got the soil with just
a little bit of residue cover.
If you want more information about cover
crop species and their growth cycle,
and those types of things, we have a
tool that looks like a periodic table.
You actually click on the different plants
you're looking for and it will open a window
that will give some more
information about those plants.
So you can choose and tailor your cover crops
to what it is that you need to have them for.
You can make sure that the system is provided
with everything that it needs to be able
to function; things that are going to be able to
grow at the different times that you want them
to grow, things that are able to use more water
or use less water depending
on your moisture conditions.
All of those things you can pick out and you can
tailor this crop to be able to function with.
I'm going to try and talk very quickly.
I know we're kind of going over
time and I apologize for that.
I want to talk quickly about soil aggregates,
these pellets that are in the soil.
In the lower right hand picture, I
want to point this out because a lot
of people are, you know, "My soil is too sandy.
I can't grow stuff here.
You know, I can hardly grow my cash crop how
do can you expect me to grow my cover crop?
I can't get all of these benefits because
I can't get organic matter in my soil,"
all of these different things
that they're talking about.
This lower right hand picture is actually from
a pot culture system that has been growing
for three months and when I'm doing
experiments in the greenhouse a lot
of times they use a one-to-one sand soil mix.
So I added a lot of sand and you can
see that it's fairly sandy in there.
I added a lot of sand and after three months,
I'm still getting this level of aggregation.
The picture on the lower left
is actually a millet root
that was planted as part
of a cover crop mixture.
This sample was taken from a plant
that was planted on July 7th.
I collected these roots on August
31st and the previous crop,
before the cover crop was
put in, was a forage pea.
This is on the particular cover crop root and
you get all of those aggregates that are formed
in that rhizosphere environment
right around the root.
You can't even really see the root.
It's hidden by all of these aggregates.
So, again, in a very short period
of time in very sandy soil --
the picture on the left was actually -- it's
a sandy loam soil that it was growing on.
So, you know, in these soil environments you
can still get a high level of soil aggregation.
The soil aggregates again, have been
reformed by the amount of the fungal hyphae.
The fungal hyphae you can't see in this picture.
It's clear hyphae, but you can see the effect
of it because it's holding those clumps together
and those clumps right now, are primarily just
I separated them from the soil by wet sieving.
So they're primarily just plant debris and
fungal hyphae, and a little bit of clay minerals
and possibly a little bit of silt minerals.
But there's not very much sand in here
and you'll see how the fungal hyphae --
I did wet sieving, so I broke this up and then
I washed it off of the sieve into a glass plate
and I let it sit for a couple of hours and
it started forming these nets that started
to bind all of this material together.
So this is sort of a pre-aggregate formation.
When you get aggregation you reduce the
amount of compaction in your system.
You're going to get -- those pellets
come in different shapes and sizes,
and so they don't fit together exactly and so
they create space in between them and that space
in between them is the porosity, the
amount of porosity that you have in soil.
When you have greater porosity you're going
to have greater levels of microbial activity
and microbial growth because that
porosity helps moisture get into the soil.
It also helps air to get in the soil
and it helps CO2 to escape the soil.
Most of the organisms that are in the soil
conduct respirations the same way we do.
They take in oxygen and they give off CO2.
But they are, again, trapped in the environment
and the amount of compaction that you have
when you reduce the level
of porosity because you're
in a compacted environment the
less those gasses can exchange
so the less microbial growth
you can get in that environment.
Water management is an important part of
having these aggregates because you're creating
that porosity where you can get water
to go into the soil much more quickly
and you can keep water stored in the soil for
a longer period of time because it is stored
in that pore space, in that open space.
And I like to -- this is a study that was
done in Missouri and I like to sort of point
out that kind of it was summary on several
studies that were done called the 'drought myth'
and basically, what it said was that
you could have unfertilized corn
that would require 26,000 gallons of
water per bushel, but if you fertilized
that field you only need 56
gallons of water per bushel.
And what is it that is happening here is
that you have greater fertility
in that soil environment.
The plant roots, in order to get fertilizer from
the soil, give off water to create mass flow
for the different fertilizer
-- for the different nutrients;
for nitrogen to flow towards the plant roots,
for phosphorus to flow towards the plant roots.
They give off water to do that.
But if you can circumvent the amount of water
that they give off, either by adding a lot
of synthetic fertilizer really close to where
you plant the seed, so if the plant is able
to acquire a lot of that
fertilizer and utilize it
with very little water give
off for the fertilizer to move.
Or, if you can circumvent it via the mycorrhizal
fungi, which I said are very efficient at going
out from the plant roots so the plant
roots don't have to give off any water.
They give a little bit of
water to the fungal hyphae,
but for the most part the fungal hyphae
acquire that water from the soil.
So the fungal hyphae grows out of the
roots and then picks up those nutrients
and carries them back to the plants.
You don't get a lot of this water loss and it's
going to require less water in your system.
As you increase the porosity level
of your system you get 44% greater --
as you increase the amount of
porosity you have in your system,
you can increase the amount of infiltration.
And just if you increase the porosity by
about half, you can go from 167% to increase
in water infiltration for the first inch
and 650% increase for the second inch.
So it dramatically increases the
amount of infiltration you have.
The porosity also can reduce the
amount of drying that you have
because basically what it forms is it -- as
you have those aggregates that are there,
the water has to move and curve, and
bend around where the aggregates are
because those pores aren't straight
channels from the surface into the soil.
Because of those moves and
those bends in the curves,
the evaporation off of the
soil surface is slowed.
It's basically like putting bends in a straw.
If you put bends in a straw, it takes more
energy to try and suck out the water that's
at the bottom versus if you don't have
bends in the straw it's really easy,
you don't have to suck very hard.
So what you want to do is you want to have bends
in the straw that's connecting the above-ground
to the below-ground so that more water
is going to stay in that environment.
Water infiltration rate increases.
You've got a conventional system that's on
the left hand side, conventionally tilled
and as you can see most of
the soil that's at the bottom,
this is down about three inches
from a rain fall simulator.
You can see most of the soil
at the bottom is not wet.
If you go to an undisturbed
system, a no-till type system,
what you're getting is you're
getting more water that's making it
through so this is saturated
all the way down three inches.
It also has higher organic matter
levels than in the conventional system
as you can see by the color differences.
[ Silence ]
>> So when you get aggregates in systems
you're going to improve porosity,
which is going to reduce compaction,
allow for better root growth.
It's going to allow for better
aeration, better water infiltration,
and better water holding capacity.
The aggregates are also going to be
a lot less susceptible to erosion
because when you have material that's bound
together in a pellet, it's larger in size
and it's going to take more energy, stronger
rainfall or stronger windstorm to be able
to move that than it is going to
be for all of the fine particles
that would be individually in the soil.
And it's going to improve the nutrient cycling
by providing a protective
habitat for the bacteria.
It's going to protect organic matter
and that's going to be a good source
for the bacteria as far as food is concerned.
You're going to be able to have this
better environment in the system
for better root growth and
for better microbial growth.
This basically illustrates some of
the management impacts on the amount
of aggregates and the stability of aggregates.
In the top three pictures,
you have one that came
from a conventional till,
spring wheat fallow system.
The next one is a no-till spring
wheat, winter wheat, sunflower system
and the last one is a moderately-grazed pasture.
These aggregates were separated from the
soil by passing through a series of screen
so they're all one to two
millimeters aggregates.
They're all the same size.
When you add the same amount of water to
these dishes, what you'll find is the WSA
or water stable aeration increases
as you go from a management system
that has less soil disturbance and more
plant growth for a longer period of time.
And you also increase the amount of TG,
which is a, excuse me, a total glomalin,
which is a polysaccharide type of substance
that's produced by mycorrhizal fungi.
It helps to contribute to the
stability of the aggregates.
You get -- as you change management you
actually impact, on a relatively small scale,
these aggregates and that's going to
have a really strong impact on all
of these other activities that you want,
reducing compaction erosion and the like.
So what you really want to do is focus on
management and not just getting the job done,
not just completing it, but
actually looking at the steps
that you utilize in your whole entire system.
And I believe that the new green revolution
is actually going to be a brown revolution.
It's going to be looking at
the soils and soil environment,
figuring out how to utilize resources the
most efficiently, getting those resources
into where they need to get in with
the least amount of loss of water
and the least amount of cost to carbon.
And this doesn't really mean
they should have to work all
that much harder, you just have to work smarter.
You have to, again, look at
your whole entire system.
You have to look for what
you need for pest management
and what's the best, most
efficient option for that.
Look for increasing the balance
in your carbon and nitrogen ratio.
So having high carbon, low nitrogen, and high --
low-carbon, high-nitrogen plants in your system,
you want to make sure that you protect your
soil, keeping it covered by living plants
with different leaf sizes
and different placements
or by having residue on that
surface of the soil.
You want to keep that soil environment protected
from temperature increases as
well as rain fall and wind.
So you want to make sure that
that environment stays there.
And again, you really want
to use your water resources
and your nutrient resources most efficiently.
It doesn't matter where you
are, that's what you want to do.
Whether you're in a dry environment or
a humid environment, a cold environment
or a warm environment; all you want
to do is improve the efficiency
so what are the steps you can take to do that.
And thank you, again, I apologize
for taking so much time.
If you want to contact me, that's
my contact information at the bottom
and I guess we'll go for some questions.
>> Yeah, [chuckle] I hope everybody
appreciates the presentation you just heard.
If you've ever had to make a
presentation sitting in a room by yourself
and to cover a topic so thoroughly and
discuss it for 90 minutes; I'm very impressed.
Fortunately, we've been able to capture this and
it's been recorded and I'll show you in a second
where you can go back because I'm sure a
lot of us are going to want to do that.
Operator, right now we -- we have an
opportunity to -- let's take a few minutes;
I know we're running over, but
hey, we've got nothing else to do.
Take a few questions and see
what's -- if anybody's out there.
I'm not sure.
You know, there might be -- I had a couple
here -- there's a lot of controversy out,
I know in the Great Lakes area, Chris,
about earthworm holes and the movement
of specially dissolved phosphorus.
You got a comment on that?
Is that -- have you done any
research or read anything on that?
You know, they're actually blaming some of the
contamination of the Great Lakes on no-till
and water movement down into field tile.
Have you got any experience or
comment something like that.
>> I guess I would say I don't have much
direct experience with some of that.
As far as the earthworm tunnels
go, I would say that they're --
although they're creating a tunnel to be able
to get water into the soil pretty quickly
and that can move some phosphorus and
it can move some nitrogen into that soil
and that can get into your tile
drainage system and possibly even get
into the groundwater system
a little bit more quickly.
But what they are doing as far as increasing the
amount of carbon that's going to be available
to the different microbial species that are
going to be able to utilize that nitrogen
and phosphorus in a way that's going
to keep it out of the river systems
and lake systems is going to, in
the long run, be more beneficial.
There may be, you know, just like
anything, there may be a few places
in which it's not working quite
as well as it should or, you know,
the system just hasn't gotten to that point.
The other thing, by having the
microbes growing at that --
along those tunnels, and the polysaccharides
that are left behind by the earthworms
that can really help contribute
to aggregate formation.
And when you contribute to aggregate
formation that's another way of locking up some
of those nutrients because you're going to
-- they're going to be inside the aggregates
and the aggregates, again, are going to create
those tunnels and those channels that are going
to have curves and bends in them,
which will slow the rate of flow
of the water as well as those nutrients.
>> Okay, thank you.
We had a question come in.
And somebody wants to know what
the role of higher animals,
grazers in the overall nutrient
cycling and in this whole discussion
about improving soil quality and the soil bio.
How significant is that to work into a system?
>> It's something that we're
learning more and more about.
Again, there's been a lot of decoupling
of grazing systems from agronomic systems
and as we see those systems come back together,
we're actually seeing better nutrient cycling.
And there's something that goes on with
grazing that I don't fully understand
and I don't think anybody fully understands
because we try and look at the microbes
that are left behind in the manure,
the microbes that are growing
in the near -- where the urine is excreted.
And we're not able to figure out exactly
what's happening, but there's something
that is occurring with, possibly with what
types of organisms they are or what some
of the activities they're having in that
particular environment, that can't be replicated
by haying it off or you know,
mowing down that residue.
There's something with having that higher animal
on the fields and on the system that's going
to allow for better management
of those nutrients.
And especially if you're putting the
livestock out to graze the fields
or graze pasture systems rather
than having them in feed lots
because you're getting a greater distribution
of those nutrients that come from the manure
and from the urine as well as the
microbial populations that come
out of the ruminants with the manure.
>> Okay, I've got two questions and
then we'll close this thing off.
You introduced a new term; sustainable tillage.
What is that?
>> Ah, [chuckle], sorry.
Sustainable tillage is going
away from the moldboard Plow.
So it's sort of a reduction in tillage.
I heard about it as a kid from what my dad was
doing when they went to these different things
with doing terraces and going away from
the number of passes that they were doing.
So they were doing fewer passes
in the fall and you know,
trying to just create the seedbed in the spring.
It's still doing tillage,
but it's sort of modifying it
from the more conventional intensive
multitask deep tilling type of equipment.
>> Okay. Okay.
We've probably coined the phrase
conservation tillage or...
>> Conservation tillage, yeah.
>> Okay. I had a question come in about
the use of BT crops and what is the effect
that these are having on biological
activities and is it going to be problem
with excessive residue because
we've heard that there's a slowing
down of the breakdown process using BT crops?
>> Yeah, I have also seen quite a bit
of data that's looking at the slowing
down of the residue decomposition of BT crops.
I've looked at several different
research papers.
I haven't conducted research in that
area, but I have some colleagues that have
and there are some that have
looked at the microbial community
and have said there's no difference
between BT corn and non-BT corn
and there are some that have said that there is.
A lot of that, I think, does have
to do with where you were sampling.
Like I said, sometimes you'll hit the
spot that is the greatest spot on earth
and sometimes you'll hit
the poorest spot on earth
in the same field under your sampling regime.
So I think that we're going to find
that a lot of it has to do with that.
We're finding out more and more about what's
happening in a rhizosphere environment
with introducing genetics and introducing
some of the pesticides that we use
and the impact that that's having.
That's just -- I think I'm going to say, more
of a stay-tuned than we really have any answers,
but we're definitely working there.
>> Okay. Last question, the soil-food web
analysis that's available out there from --
well, I guess it's from the soil-food
web; you've got a comment on that?
Is that something that's worth pursuing or...
>> I do -- the soil-food web analysis
and I've worked with several people
who have sent some samples for soil-food
web analysis, there's been a few places
in which I think some of their methodology
have some problems with it as far as being able
to get some good numbers for, especially, I
did stem analysis on mycorrhizal colonization
and ended up getting some very different
numbers from the soil-food web lab.
So, you know, I think there's some information
that we can take from there and, you know,
look at things like the amount of protozoa and
nematodes, and bacteria to maybe get some ideas
about nitrogen, potential nitrogen availability.
I think there are some other labs that are
coming online that are trying to do analysis
on the soil-food web and they may have
some better ways of looking at it.
Some of it may be a little
bit harder to interpret.
We do things like fatty acid analysis and DNA
analysis to try and identify groups of organisms
and sometimes that can be difficult
to do and expensive to do as well
as a little bit difficult to interpret.
And the more we're building
up a database of information
for agricultural food the
soil-food web is located in Oregon.
It's works -- it's been associated
mostly with the horticultural industry,
which is a very different environment because
usually they completely sterilize their soil.
So I think that just like with soil testing,
there's some misinterpretation that can be made
because we don't know what
the baseline should be.
So the more we can get different soils
analyzed the more we can get information
on what the baseline should be so what makes
things good or bad because we don't really know
that very well for a lot of agronomic systems
as far as individual species and amounts needed.
>> Okay, all right.
Thank you, doctor.
For those, a soil-food web analysis is just
a measurement, a quantitative measurement
of the various organisms that
Dr. Nichols talked about.
Again, we appreciate your participation.
Just before I close out, I just want
to make folks aware of two things.
You can listen to a replay of
this presentation at this website,
which is the new Science and
Technology Training Library.
If you go to that, I'll just click on it
real quick; this is what it looks like.
You can access it there at the
address that's on the webinar.
Here's the one -- the last one we did.
We will post this presentation there.
If you hit download, you'll just simply go
to a PDF file here that gives a description
of what the objectives were, gives a basic
description of what the training session was,
and then you can either hit play or download.
I would suggest you hit the download because
that gives you the opportunity to pause and back
up or fast forward through the
presentation where the software,
if you hit the play, doesn't
allow you to do that.
And then the final, make sure you get your
presentation or your information into us
about the -- if you have, your CCA credits.
Make sure you get that information either
faxed or emailed to Holli Kuykendall.
And then the last thing is, our next
MRBI presentation will be on Wednesday
and that should be August the 10th, not July
the 27th, that's a cut and paste error there.
So again, Wednesday, August the 10th.
It'll be Mark Scarpitti who's
the state agronomist from Ohio,
and he's going to be building on
what Dr. Nichols talked about,
how can you take these principles and put
them into a conservation plan and use them
as the foundation for resources management,
looking at planting to improve soil health,
managing more by disturbing less, diversifying,
growing a living root throughout the
year, and keeping the soil covered.
Those are the basic principles he'll
be covering and he'll be talking
and just kind of expounding on that.
With that, I appreciate everybody's
participation.
Again, Dr. Nichols, you did a great job.
And I am sure, everybody, from the
responses I'm seeing and the Q and A,
and the applause I'm getting over the
computer here, everybody's in agreement.
So again, we thank you and I guess
that will just call it a day.
Thank you.
>> Thank you.
>>
[ Silence ]
