Increasing Soil Organic Matter
Its all about
carbon!
The higher the organic matter, the greater the Cation-exchange capacity (CEC), and the better the yields and nutrient density!
Most growers are looking for ways to increase their organic matter. They try growing cover crops, also called green manure, utilizing crop litter, compost and mulch. Even though these methods do work, they are not the long-term answer for creating organic matter in the soil. There is a much better solution!
The secret formula is:
Organic matter is CARBON, and
CARBON is organic
matter.
In the interview below, Dr. Christine Jones explains that the fastest and very best way to increase organic matter and build rich topsoil is through carbon sequestration. Read the article and you will know the secret of how to greatly increase this sequestration of sugars down into the soil.
Should we feed the plant directly with NPK or should we utilize microorganisms to convert tied up nutrients into available plant food?
AG-USA is passionate about the following two
things, and believe that these two things
have the potential to revolutionize
agriculture:
At the end of the article we share how MycorrPlus-A and O (formerly called GroPal Balance) greatly facilitates the above process, resulting in increased RFV and plant growth.
To
the pressing worldwide challenge of restoring
soil carbon and rebuilding topsoil,
the Australian soil ecologist Dr. Christine
Jones offers an accessible, revolutionary
perspective for improving landscape health
and farm productivity.
For several decades Jones has helped innovative farmers and ranchers implement regenerative agricultural systems that provide remarkable benefits for biodiversity, carbon sequestration, nutrient cycling, water management and productivity.
The following article is reprinted from the March, 2015 edition, volume 45, #3 of AcresUSA Magazine
Dr. Christine Jones, Interviewed by Tracy Frisch
ACRES U.S.A. You've
written that the most meaningful indicator
for the health of the land and the long-term
wealth of a nation is whether soil is being
formed or lost. Yet there's a widespread
belief, actually dogma, that the formation
of soil is an exceedingly slow process. Even
some organic researchers accept that idea.
You describe the formation of topsoil as
being breathtakingly rapid.
DR. CHRISTINE JONES.
People have confused the weathering of rock,
which is a very, very slow process, with the
building of topsoil, which is altogether
different. Most of the ingredients for new
topsoil come from the atmosphere ? carbon,
hydrogen, oxygen and nitrogen.
ACRES U.S.A. Why
have many soil scientists denied the
phenomenon of rapid soil-building?
JONES.
Because they do their research in places
where it's not happening, where the carbon
is running down and the soils are
deteriorating. We need to measure carbon on
farms where soil-building is occurring and
see what the farmers and ranchers are doing
to make that happen.
ACRES U.S.A. The
process of fixing carbon in the soil seems
to be the crux of your work. You describe a
cycle with carbon in three phases: as a gas,
a liquid and a solid.
JONES.
The issue we're facing is that too much of
the carbon that was once in a solid phase in
the soil has become a gas. That could be
dangerous for the human species. Climate
change is just one aspect. Food security,
the nutrient density of food and the
water-holding capacity of the soil are also
very potent reasons for keeping carbon in a
solid phase in the soil.
ACRES U.S.A. Your
term "liquid carbon" is such a brilliant
phrase.
It has really helped me conceptualize the
carbon cycle. What do you mean by it?
JONES. Liquid
carbon is basically dissolved sugar.
Sugars are formed in plant chloroplasts
during photosynthesis. Some of the sugars
are used for growth and some are exuded into
soil by plant roots to support the microbes
involved in nutrient acquisition.
ACRES U.S.A. I remember bringing up the idea of leaky roots in a conversation with you and you laughed.
JONES.
At first people thought "leaky" roots were
defective. Exuding carbon into the soil
seemed such a silly thing for plants to do!
Then it became recognized that some of the
exudates were phenolic compounds with
allelopathic effects, important in plant
defense. Of course we now know that plant
roots exude a vast array of chemical
substances, all based on carbon, to signal
to microbes and to other plants. But perhaps
the most significant finding, at least from
a human perspective, is that the
flow of liquid carbon to soil is the primary
pathway by which new topsoil is formed.
ACRES U.S.A. All
of which revolves around the concept of a
plant-microbial ridge?
JONES.
In order for carbon to "flow" to soil, there
has to be a partnership between plant roots
and the soil microbes that will receive that
carbon. Somewhere between 85 to 90 percent
of the nutrients plants require for healthy
growth are acquired via carbon exchange,
that is, where plant root exudates provide
energy to microbes in order to obtain
minerals and trace elements otherwise
unavailable. We inadvertently blow the
microbial bridge in conventional farming
with high rates of synthetic fertilizers or
with fungicides or other biocides.
ACRES U.S.A. Are
you observing an increased awareness of the
significance of biological processes?
JONES.
There is a lot more energy generated through
biological processes than through the
burning of fossil fuels. Most life-forms
obtain their energy either directly or
indirectly from the sun, via the process of
photosynthesis. Plants are what we call
autotrophs. That is, they feed themselves by
combining light energy with CO2 to produce
biochemical energy. As heterotrophs, we
obtain energy by eating plants or eating
animals that ate plants. In effect, we're
running on light energy too. Even microbes
in a compost heap are obtaining energy by
breaking down organic materials originating
from the process of photosynthesis.
ACRES U.S.A. You
distinguish between organic matter formed by
the decomposition of manure, crop residues
or other carbonaceous materials ? and humus
? which is generated via a building-up
process. I think a lot of times that is
misunderstood.
JONES. It's a really important distinction, but it's often overlooked. In order to obtain the energy that is contained in cellulose, lignin, starches, oils, waxes or other compounds formed by plants, microbes have to break this material down ? the same as we do when we digest starches or proteins or anything else of plant or animal origin. We breathe out more CO2 than we breathe in, because as we utilize the energy we obtain from the assimilation of food, our cells release CO2.
The decomposers in the soil are doing
exactly the same thing ? breaking down
organic materials and releasing CO2. These
processes are catabolic. Conversely, the
formation of humus is an anabolic process,
that is, a building-up process. Rather than
sugar being the end point, sugar is the
start point. Soil microbes use sugars to
create complex, stable forms of carbon,
including humus.
ACRES U.S.A. How
would you define humus?
JONES.
Humus is an organo-mineral complex
comprising around 60 percent carbon, between
6 and 8 percent nitrogen, plus phosphorus
and sulfur. Humic molecules are linked to
iron and aluminum and many other soil
minerals, forming an intrinsic part of the
soil matrix. Humus cannot be "extracted"
from soil any more than wood can be
"extracted" from a tree.
ACRES U.S.A. You
frequently mention mycorrhizal fungi in your
work. What makes them so special?
JONES. Much of the initial research into mycorrhizal fungi was related to the uptake of phosphorus. Phosphorus is a highly reactive element. As soon as there's any free phosphorus floating around in the soil, including whatever we may add as fertilizer, it becomes fixed. In other words, it forms a chemical bond with another element like iron or aluminum or calcium, making it unavailable to plants. But certain bacteria produce an enzyme called phosphatase that can break that bond and release the phosphorus.
Once released, the phosphorus still has to be transported back to the plant, which is where mycorrhizal fungi come in. As our analytical techniques have become more sophisticated, we've realized that mycorrhizal fungi also transport a wide variety of other nutrients, including nitrogen, sulfur, potassium, calcium, magnesium, iron and essential trace elements such as zinc, boron, manganese and copper. In dry times they supply water.
Mycorrhizal fungi can extend quite a
distance from plant roots. They form
networks between plants and colonies of soil
bacteria. Plants can communicate with each
other via messages sent through these
networks. Mycorrhizal fungi are both the
highway and the Internet of the soil.
ACRES U.S.A. How
can something so important be overlooked?
JONES.
Much of the agricultural research undertaken
in pots in glass houses is fundamentally
flawed. Soil is homogenized to remove
background noise, that is, to make the soil
in all the pots similar at the outset. The
blending process breaks up the hyphae of
mycorrhizal fungi. In some trials the soil
is also sterilized to eliminate any
microbial activity that could interfere with
the treatment being assessed. And often the
soil has been stored for a long time prior
to the experiments, which means most of the
soil organisms have died. In such an
environment, plants are likely to respond to
applied fertilizer, as they have no other
means to obtain nutrients. Similarly with
field trials, if the soil has been
cultivated or bare fallowed, mycorrhizal
fungi will not be there in sufficient
quantities for effective carbon flow and
nutrient acquisition. In healthy,
biologically active soils, we do not see a
response to synthetic nitrogen or phosphorus
fertilizers. If anything, the use of these
is counterproductive.
ACRES U.S.A. I've
learned from you that plants colonized by
mycorrhizal fungi can grow much more
robustly even though they're giving away as
much as half of the sugars that they make in
photosynthesis through their roots.
JONES.
That's correct.
ACRES U.S.A. So
we have this system characterized by
abundance and generosity, and that's really
different from the way we are used to
thinking about growing crops.
JONES.
The point that's often missed is that a
mycorrhizal plant photosynthesizes much
faster than
a non-mycorrhizal plant of the same species
growing right next to it. The plant is able
to give half its energy away and still grow
stronger because of the symbiotic
relationship with the fungus. It doesn't
cost the plant anything to photosynthesize
faster. It's just using sunlight more
efficiently. Remember, plants are
autotrophic.
ACRES U.S.A. And
sunlight is free.
JONES.
CO2 is free too. If
a plant photosynthesizes faster it's going
to have higher sugar content and a higher
Brix level. Once Brix gets over 12, the
plant is largely resistant to insects and
pathogens. High-Brix plants have formed
relationships with soil microbes able to
supply trace elements and other nutrients
that the plant needs for self-defense, for
its immune system. When plants are able to
produce high levels of plant-protection
compounds, the insects go elsewhere.
ACRES U.S.A. We
tend to think that minerals in the soil are
scarce because most of them are not in a
form available to plants.
JONES.
A soil test will only tell you what is
available to plants by passive uptake. The
other 97 percent of minerals - made
available by microbes - will not show up on
a standard test. By
looking after the microbes in the soil we
can increase the availability of a huge
variety of minerals and trace elements -
most of which are not even in fertilizers.
ACRES U.S.A. We
always hear the story about fields that were
continuously cropped or hayed for 30 years
where the soil is so exhausted that we have
to add a lot of nutrients or we can't grow a
thing.
JONES. The problem is that we interrupt carbon flow with the way we farm. Cultivating the soil and using chemical fertilizer and pesticides break up the mycorrhizal networks. If plants can obtain nitrogen or phosphorus easily, they will stop pumping carbon into the soil to support their microbial partners.
It's taken a while for people to realize that plant root exudates are not only important for nutrient exchange, but also essential for the maintenance of topsoil. If carbon is not flowing to soil via the liquid carbon pathway, soil deteriorates. Carbon is needed for soil structure and water holding capacity as well as for feeding the microbes involved in nutrient acquisition.
When soil loses carbon, it becomes hard and compacted. The differences in infiltration and moisture retention between high and low carbon soils are dramatic. Planetary stocks of fresh water are declining alarmingly. More efficient water use is going to be absolutely critical to the survival of our species.
Making better use of water requires improved
soil structure - which in turn requires
actively aggregating soils. If aggregates
are breaking down faster than they're
forming, the water-holding capacity of soil
can only deteriorate.
ACRES U.S.A. How
can we tell if a soil has good aggregation?
JONES.
Dig a hole and take a handful of soil.
Squeeze it gently and release. If the soil
is well aggregated, it will look like a
handful of peas. If the soil remains in hard
chunks that don't break easily into small
lumps, then it isn't well aggregated.
ACRES U.S.A. What
processes are going on inside of a soil
aggregate?
JONES. The aggregate is the fundamental unit of soil function. A great deal of biological activity takes place within aggregates. For the most part, this is fueled by liquid carbon. Most aggregates are connected to plant roots, often to very fine feeder roots, or to mycorrhizal networks unable to be detected with the naked eye.
Liquid carbon streams into the aggregates via these roots or fungal linkages, enabling the production of glues and gums that hold the soil particles together. If you gently lift a plant from healthy soil, you'll find aggregates adhering to the roots. The moisture content is higher inside a soil aggregate than on the outside, and the partial pressure of oxygen is lower on the inside than on the outside. These important properties enable nitrogen-fixing bacteria to function.
When aggregates aren't forming ? because
of cultivating the soil or using chemicals
or having bare soil for six months or more
with no green plants ?
crops are not able to obtain sufficient
nitrogen. The tendency is then to add
fertilizer nitrogen, exacerbating the
situation. The application of large
quantities of inorganic nitrogen interrupts
carbon flow to soil, further reducing
aggregation.
ACRES U.S.A. It
sounds like a vicious cycle.
JONES.
Yes, the more N applied, the more soil
structure deteriorates and ironically, the
less N is available to plants. you'll
rarely see a nitrogen deficient plant in a
healthy natural ecosystem.
When I was driving home yesterday I noticed
yellow, nitrogen deficient pastures on many
of the dairy farms I passed. But in the area
between the fence and the road, where no
fertilizer had been used, the grasses were a
lovely dark green.
ACRES U.S.A. We
are familiar with Rhizobium bacteria and
their relationship with legumes. What should
we know about free-living nitrogen fixing
bacteria?
JONES.
From an agricultural perspective the most
important of the freeliving nitrogen-fixing
bacteria are associative diazotrophs ?
so-called because the atmospheric nitrogen
that they fix occurs as di-nitrogen
(N2) and associative because, like
mycorrhizal fungi, they require the presence
of a living plant for their carbon. These
bacteria live in close proximity to plant
roots or are linked to plant roots via the
mycorrhizal highway.
ACRES U.S.A. isn't
our knowledge of these organisms pretty
recent?
JONES. The reason we know so little about associative diazotrophs is that most cannot be cultured in the lab. This applies to most species of mycorrhizal fungi as well. As bio-molecular methods for detecting microbes in the soil become more sophisticated, we're realizing there is a lot more life ? and a lot more species ? than we thought. It has become obvious that there are thousands of different types of bacteria and archaea that can fix nitrogen.
The Haber-Bosch process, by which we
manufacture nitrogen fertilizer, is a
catalytic reaction requiring enormous
amounts of energy. Yet microscopic bacteria
in the rhizosphere or within
plant-associated aggregates can fix nitrogen
simply using light energy from the sun,
transformed to biochemical energy during
photosynthesis and channeled to soil by
plant roots.
ACRES U.S.A. I'm
a little confused because I understood that
there is a difference between mineral
nitrogen and organic nitrogen.
JONES. That's correct. Nitrogen fixing bacteria produce ammonia, a form of inorganic nitrogen, inside soil aggregates and rhizosheaths. Rhizosheaths are protective cylinders that form around plant roots. they're basically a bunch of soil particles held together by plant root exudates. You can easily strip them off with your fingers.
Within these biologically active environments the ammonia is rapidly converted into an amino acid or incorporated into a humic polymer. These organic forms of nitrogen cannot be leached or volatilized. Amino acids can be transferred into plant roots by mycorrhizal fungi and joined together by the plant to form a complete protein.
On the other hand, inorganic nitrogen applied as fertilizer often ends up in plants as nitrate or nitrite, which can result in incomplete or "funny" protein. This becomes a problem in cattle if it turns up as high levels of blood urea nitrogen (BUN) or milk urea nitrogen (MUN).
Nitrates cause a range of metabolic
disorders including infertility, mastitis,
laminitis and liver dysfunction. There is
also a strong link between nitrate and
cancer. In some places in the United States
it is not safe to drink the water due to
excessive nitrate levels. Milk can also have
nitrate levels above the safe drinking
standard, but people happily consume it, not
realizing it's unhealthy.
ACRES U.S.A. These
are great points. How dependent is the world
on the application of synthetic nitrogen?
JONES. Farmers around the world collectively spend about $100 billion per year on nitrogen fertilizer. I'm greatly inspired by the multi-species over crop revolution in the United States. Leading-edge farmers like Gabe Brown, Dave Brandt and Gail Fuller are showing it's possible to maintain or even improve crop yields while winding back on fertilizer. These farmers are light years ahead of the science.
they're building soil, improving the
infiltration of water, increasing water
holding capacity and getting fantastic
yields. They have fewer insects and less
disease. The carbon and water cycles are
fairly humming on their farms.
ACRES U.S.A. I
want to get your recipe for transforming
terra-cotta tile into chocolate cake ? that
is, turning hard, compacted soil into loose,
fragrant soil teeming with life.
JONES. There isn't a ?recipe? as such for maintaining soil aggregates (the starting point for chocolate cake). It's really just a set of guiding principles. Soil becomes like a terra-cotta tile when aggregates break down. Hard, compacted soil sheds water. The amount of effective rainfall is dramatically reduced. It's also much harder for plant roots to grow in poorly aggregated soil.
The first rule for turning this around is to keep the soil covered, preferably with living plants, all year round. In environments where the soil freezes, it's still important to maintain soil cover with mulch or a frost-killed cover crop or better still, a frost-hardy cover that will begin to grow again as soon as spring arrives.
Microbes will go into a dormant phase over
winter and re-activate at the same time as
the plants. In regions with a hot, dry
summer, evaporation is enemy number one.
Bare soil will be significantly hotter and
lose more moisture than covered soil.
Aggregates will break down unless the soil
is alive. Aggregation is absolutely vital
for moisture infiltration and retention.
ACRES U.S.A. OK,
so that's one.
JONES. Point two is to maximize diversity in both cover crops and cash crops. Aim for a good mix of broadleaf plants and grass-type plants and include as many different functional groups as possible. Diversity above ground will correlate with diversity below ground. Third, avoid or minimize the use of synthetic fertilizers, fungicides, insecticides and herbicides.
It's a no-brainer that something designed to kill things is going to do just that. There are countless living things in soil that we don't even have names for, let alone an understanding of their role in soil health. It's nonsense to say biocides don't damage soil! In Australia many farmers plant seeds treated with fungicide "just in case." they're actually preventing the plant from forming the beneficial associations that it needs in order to protect itself.
After a few weeks of crop growth, they will then apply a "preventative" fungicide, which also finds its way to the soil, inhibiting the soil fungi that are essential to crop nutrition and soil building. The irony is that plants are then unable to obtain the trace elements they need to fight fungal diseases. We see many examples of crops grown biologically that are rust-free, side-by-side with rust infected plants in neighboring fields where fungicides are being used.
There is an analogous situation with human
health. Not that long ago the cancer rate
was around one in 100. Now we're pretty
close to one in two people being diagnosed
with cancer. At the current rate of
increase, it won't be long before nearly
every person will contract cancer during
their lifetimes. Cancer is also the number
one killer in dogs. isn't that telling us
something about toxins in the food chain?
we're not only killing everything in the
soil, we're also killing ourselves ? and our
companion animals. Is that what we want for
our future?
ACRES U.S.A. Are
you a cancer survivor?
JONES.
Yes, I am, which is basically why I do what
I do. But I don't say a lot about that
because if you start your talk with "we're
all going to die from cancer unless we
change," people tune out. It's too
threatening. Most of us have lost loved ones
through cancer.
ACRES U.S.A. You
say it's not just the toxins in our food
that are the problem, but the use of
biocides "chemicals that kill living
organisms" which reduce the nutrient
content of food. And you attribute that
nutrient reduction to the inhibition of the
plant-microbial bridge.
JONES.
Spot on. If the plant-microbe bridge has
been blown, it's not possible for us to
obtain the trace elements our bodies need in
order to prevent cancer ?
and a range of other metabolic disorders.
Cancer is not a transmissible disease. It's
simply the inability of our bodies to
prevent abnormal cells from replicating. To
date, the response to the cancer crisis has
revolved around constructing more oncology
units, employing more oncologists and
undertaking more research. The big
breakthrough in cancer prevention will be in
changing the way we produce our food.
ACRES U.S.A. We
have plenty of evidence from meta-studies
that the nutrient content of produce grown
organically tends to be higher than produce
grown chemically. We also have documentation
of steep declines in nutrient content in a
number of foods over the last century.
JONES.
Yes, we're getting a double whammy. we're
ingesting chemical residues, but not the
trace elements and phytonutrients we need
for an effective immune response. Plants
need trace elements, like copper and zinc,
to make these phytonutrients. But the trace
elements will not be available in the
absence of an intact microbial bridge.
ACRES U.S.A. You've
talked about the pressure on farmers to have
tidy farms and uniformity in their fields.
It seems like one of the problems you're
identifying is a faulty understanding of
what it means to farm well and to be a good
farmer. What are some of the qualities that
farmers think they should have that get in
the way of building healthy soil?
JONES. I must admit that in the early '90s, when I first started going onto farms that were using holistic planned grazing, I was a bit shocked to see the number of weeds popping up. These weeds would have been sprayed under the former management regime, but the ranchers were saying, ?don't worry. We have to pass through this weedy stage. If we spray weeds, we create bare ground and the weed seed that's there means the weeds simply come back.?
There's a saying, "the more you spray weeds, the more weeds there will be to spray." It's oh so true! Continually reverting to bare ground creates more problems than it solves. Those ranchers knew some weeds had deep roots that bring up nutrients. Leaving them there meant better quality plants would eventually be able to grow in the improved soil and replace the weeds. That is exactly what happened. Over the last 60 years we've tried ? and failed ? to control weeds with chemicals.
One of the exciting things about the multi-species cover crop revolution that's underway in the United States is that the greater the variety of plant types you use, the more niches you fill and the less opportunities there are for weeds. Cover-crop enthusiasts are experimenting with 60 or 70 different species in their mixes. I see the trend to polyculture as the most significant breakthrough in the history of modern agriculture. Even so, the first time you see a multi-species cover or a cash crop grown with companion plants, you might think, ?Wow, that looks untidy? because we're not used to it. It takes a little while to realize that having all those different plants together is really beneficial.
Somehow we have to change the image of what a healthy field looks like so that when people see bare ground or a monoculture, they recognize it's lacking ? and that this is not a good thing.
ACRES U.S.A. What
sort of response are the cover crop pioneers
receiving?
JONES. they're seeing fantastic results. The trouble is they are not getting the accolades they deserve. This is slowly beginning to change. NRCS, in particular, are being exceptionally supportive of these leading edge farmers. Cover cropping is now generating a huge amount of interest.
Recently I visited Brendon Rockey, a young
potato farmer in the San Luis Valley of
Colorado. Brendon has increased irrigation
efficiency 20 percent through the use of
cover crops. There is increasing worldwide
recognition of the fact that multi-species
cover crops improve soil-water
relationships.
ACRES U.S.A. Right,
another aspect of that abundance.
JONES. If there is a bare fallow between crops ? or bare ground between horticultural plantings such as grapes ? soil aggregates break down. As a result, water cannot infiltrate as quickly. It remains closer to the surface and evaporates more readily. Lack of aggregation also renders the soil more prone to wind and water erosion.
We have this fear that if we grow companion
plants or a cover crop, they're going to use
up all the water and nutrients. We have to
realize that by supporting soil microbes, a
diversity of plants actually improves
nutrient acquisition and water retention.
ACRES U.S.A. In the
transition period from a chemically
intensive system where you don't have a
functioning plant-microbial bridge,
what are some kinds of practices that
farmers can use?
JONES. Sometimes when farmers realize the importance of soil biology they immediately stop using fertilizers and chemicals. This is not necessarily a good thing. It takes time for soil microbial populations to re-establish. If the soil is dysfunctional, chances are the wheels will fall off when fertilizers are pulled. If there is a failure, farmers will revert back to what they know ... chemical agriculture.
You have to wind back slowly and accept that it's going to take time to transition. The key to getting started is to experiment on small areas. It's a matter of dipping a toe in the water. Include some clovers or peas with your wheat, or vetch with your corn ? just on one part of the field.
This reduces the risk. When farmers see that they've gained rather than lost yield ? and that the crop looks healthier ? they will be inspired to try a larger area and a greater variety of companion plants next time. Another option is to plant a multi-species cover crop on part of the land that would normally be devoted to a cash crop.
you're exceptionally lucky in the United States in that a lot of farmers are experimenting with cover crops now. Once the diversity ramps up, the ladybirds and lacewings and predatory wasps appear and the need for insecticides falls away. And after heavy rain, it's obvious that water has infiltrated better in the parts of the field where the cover crops were.
Gradually the changes become an integral
part of farming ? an exciting part, in fact.
Experimentation and adaptation become the
norm, rather than conformity. Confidence
builds, as ways to restore healthy topsoil
become firsthand knowledge.
ACRES U.S.A. What
about fertility?
JONES. It's important to cut back on chemical fertilizers slowly. If you've been using loads of synthetic nitrogen, then free-living nitrogen-fixing bacteria won't be abundant in your soil. An easy way to transition is to reduce the amount of nitrogen applied by around 20 percent the first year, another 30 percent the next and then another 30 percent the year after.
At the same time as reducing fertilizer inputs it's absolutely vital to support soil biology with the presence of a wide diversity of plants for as much of the year as possible.
Another way to gradually reduce fertilizer inputs is to use foliar fertilizers rather than drilling fertilizer under the seed. Foliar-applied trace minerals can also help during transition. These can be tank-mixed with biology-friendly products such as vermi-liquid, compost extract, fish hydrolysate, milk or seaweed extract.
Whichever path you choose to support soil
biology, the overall aim is for soil
function to improve every year. The overuse
of synthetic fertilizers will have the
opposite effect.
ACRES U.S.A. You
mentioned the longest-running field
experiment in North America that found that
high nitrogen depletes soil carbon?
JONES. The Morrow Plots are the oldest continuously cropped experimental fields in the United States. A team of University of Illinois researchers investigated how the fertilization regimes that were commenced in these plots in 1955 affected crop yields and soil carbon and organic nitrogen levels.
They discovered that the fields that had received the highest applications of nitrogen fertilizer had ended up with less soil carbon ? and ironically less nitrogen ? than the other fields.
The researchers concluded that adding
nitrogen fertilizer stimulated the kind of
bacteria that break down the carbon in the
soil. The reason there is less nitrogen in
the soil even though more has been applied
is that carbon and nitrogen are linked
together in organic matter. If carbon is
decomposing, then the soil will also be
losing nitrogen. They decompose together.
ACRES U.S.A. That's
fascinating. Tell me about David Johnson and
what he is finding in his research at New
Mexico State University.
JONES. Dr. David Johnson is based in Las Cruces, south of Albuquerque. He has discovered that the ratio of fungi to bacteria in the soil is a more important factor for plant production than the amount of available nitrogen or phosphorus.
Sadly, in most of our agricultural soils, we have far more bacteria than fungi. The good news is that farmers use multi-species cover crops, companion crops, pasture cropping and other polycultures ? and the ranchers who manage their perennial grasses with high density short duration grazing accompanied by appropriate rest periods ? are moving their soils toward fungal dominance.
When you scoop up the soil, it has that
lovely composty, mushroomy sort of smell
that indicates good fungal levels.
Oftentimes agricultural soils have no smell
or a smell that is a bit sour. Fungi are
important for soil carbon sequestration as
well as nutrient acquisition. The formation
of humus, a complex polymer, requires
several catalysts, including fungal
metabolites.
ACRES U.S.A. That
is a really interesting insight. I would
like to get some perspective on soil
degradation. You've written about how lush
and green Australia's landscape was at the
time of European settlement in the early
1800s, land that's now desertified. How do
your readers react?
JONES. They have a particularly hard time believing that the southern and southwestern parts of Australia supported green plants during our hot, dry summers. It's fortunate that some of the first European settlers kept journals. George Augustus Robinson, who was the Chief Protector of Aborigines, kept a daily journal for several years.
Robinson was a keen observer. He made
sketches of the landscape as well as
describing it. In summertime when it was
over 100 degrees and without rain for months
on end, Robinson noted green grass and
carpets of wildflowers everywhere he looked.
Sadly, we don't know what many of these
plants were because we no longer have
wildflowers in some of the colors he
recorded.
ACRES U.S.A. Could
you reconstruct what happened to destroy all
this lush, diverse vegetation?
JONES. European colonists brought boatloads of sheep which rapidly multiplied. In England you could have sheep in continual contact with the grass and it didn't matter greatly because it nearly always rained. Australian weather tends to oscillate between drought and flooding rain and the English weren?t used to that. By the late 1800s there were many millions of sheep in Australia, grazing the grasslands down to bare earth in the dry periods.
When it rained, the unprotected soil washed away. The river systems and wetlands filled with sediment. we're now farming on subsoil. We?ve lost around 2 to 3 feet of topsoil across the whole country. The original soil was so well aggregated that aboriginal people could dig in it with their bare hands.
The first Europeans to arrive in Australia talked about two feet of black ?vegetable mold? that covered the soil surface. Today our soils are mostly light-colored. The use of color to describe soils only came into being after the carbon-rich topsoil had blown or washed away. It's not an uncommon story.
Just about every so-called civilized,
developed country in the world has lost
topsoil by one means or another. In the
States you had your Dust Bowl, created by
tillage. Restoring the health of
agricultural soils will require more than
learning how to minimize soil losses. We
need to learn how to build new topsoil, and
we need to learn how to do it quickly.
ACRES U.S.A. I
read that in Australia, using the so-called
best management practices of stubble
retention and minimal tillage, wheat
production results in the loss of 7
kilograms of soil for every kilogram of
wheat harvested. Is it still that bad?
JONES.
Yes, probably worse. I have documented
evidence of 20 tons of soil per hectare per
year being lost through wind erosion. The
average wheat yield in Australia is very
low, around 1 ton per hectare. We lose
massive amounts of soil to achieve it. The
current situation is not sustainable.
ACRES U.S.A. How
much of Australia's farmland would have to
increase soil carbon to offset your
country's carbon emissions?
JONES.
It would require only half a percent
increase in soil carbon on 2 percent of our
agricultural land to sequester all
Australia's CO2 emissions. Our emissions are
low in relation to our land area because we
have a relatively small population.
ACRES U.S.A. Do
you have any idea worldwide how much
farmland would have to be managed
differently to increase soil carbon
sufficiently to reverse global climate
change or offset greenhouse gases?
JONES. Agriculture is the major land use across the globe. According to the FAO there are around 1.5 billion hectares of cropland and another 3.5 billion hectares of grazing land. Currently much of that land is losing carbon.
No doubt there will be ? and indeed there already have been ? endless arguments about how much carbon can be sequestered in soil. In my view it's not a matter of how much but how many. The focus needs to be on transforming every farm that's currently a net carbon source into a net carbon sink.
If all farmland sequestered more carbon than it was losing, atmospheric CO2 levels would fall at the same time as farm productivity and watershed function improved. This would solve the vast majority of our food production, environmental and human health problems.
I'm disappointed to see that articles are still being published in internationally recognized peer-reviewed soil science journals ? as recently as 2014 ? downplaying the potential for carbon sequestration in agricultural soils. Predictably, these articles fail to mention plant roots, liquid carbon or mycorrhizal fungi.
Many scientists have confused themselves ? and the general public ? by assuming soil carbon sequestration occurs as a result of the decomposition of organic matter such as crop residues. In so doing, they have overlooked the major pathway for the restoration of topsoil. Activating the liquid carbon pathway requires that photosynthetic capacity be optimized.
There are many and varied ways to achieve
this. I have enormous respect for the
farmers and ranchers who have done what the
experts say can't be done. If we have a
future, it will be largely due to the
courage and determination of these
individuals.
ACRES U.S.A. You
initiated the Australian Soil Carbon
Accreditation Scheme (ASCAS). I'm quite
impressed that one person started something
like that.
JONES. I launched ASCAS in 2007 out of frustration that the federal government wasn?t doing anything to reward innovation in land management. I wanted to demonstrate that leading edge farmers could build carbon in their soils and be financially rewarded for doing so. But my attempts were blocked at every level, including being subjected to public ridicule.
I suspect much of the resistance stemmed from the fact that Australia was importing over $40 billion worth of farm chemicals and policy-makers saw that as a big business. They realized that in order to build soil carbon, farmers would need to reduce chemical use. There were other issues too.
Australia ratified the Kyoto Protocol nine months after the launch of ASCAS. Under Kyoto Protocols, the issuance of carbon credits requires adherence to the 100 year rule, which basically means that any payment for soil carbon must be registered on the land title and the money refunded if for any reason the carbon levels fall over the ensuing 100 years.
Then there's the additionality rule, which
states farmers cannot be paid for changes in
land management that they would have made
anyway, or that result in higher profits.
ACRES U.S.A. You
said this story has a good ending.
JONES.
Despite the roadblocks, I felt it was
important that soil restoration pioneers be
recognized. Late last year we decided to
discard the original ASCAS model and start
afresh. On March 19, 2015, almost eight
years to the day after we launched the ASCAS
in 2007, our patron Rhonda Willson will
present 11 Soil Restoration Leadership
Awards at a farming forum in Dongara,
Western Australia. It's a fitting conclusion
that these awards be presented in the
International Year of Soils.
ACRES U.S.A. What
changes did your Soil Restoration Leaders
make in order to improve soil function?
JONES. The agricultural region of Western Australia experiences an extremely hot, dry summer. Winters are cool and moist, although not as moist as many farmers would like. Innovative ranchers have been planting summer active grasses at the end of winter when there is sufficient moisture for germination, despite ?expert? opinion that it's too hot and dry in summer for anything to grow. Perennial grasses have incredibly deep root systems and form mycorrhizal associations that help them survive.
The grasses soon create their own
microclimate. It's an absolute delight to
see these patches of green in an otherwise
parched landscape. It helps us understand
how the countryside encountered by the first
European settlers was able to remain green
over the summer.
ACRES U.S.A. At
the People's Climate March in New York City,
a large contingent of vegan activists
carried signs blaming cattle as a major
cause of global warming. What are your
thoughts on targeting ruminants for
greenhouse gas emissions?
JONES. There were more ruminants on the planet 200 years ago than there are now, but we've gone from freeranging herds to animals in confinement. That changes everything.
Firstly, we're growing feed for these animals using fossil-fuel intensive methods and secondly, confinement feeding creates a disconnect between ruminants and methanotrophs. Methanotrophic bacteria use methane as their sole energy source. They live in a wide variety of habitats, including surface soils. If a cow has her head down eating grass, the methane she breathes out is rapidly metabolized by methanotrophs.
There's an analogous situation with termites. Termites produce methane during enteric fermentation, as happens in the rumen of a cow. But due to the presence of methanotrophic bacteria, methane levels around a termite mound are actually lower than in the general atmosphere.
In
nature, everything is in balance. After the
disastrous Deepwater Horizon oil spill in
the Gulf of Mexico, the ocean was bubbling
with not only oil, but also methane. To the
astonishment of scientists monitoring the
spill, populations of methanotrophic
bacteria exploded and consumed an estimated
220,000 metric tons of methane gas, bringing
levels back to normal.
ACRES U.S.A. When
we talk about the consequences of the
increased extreme weather associated with
climate change, like devastating floods and
droughts, all too often we neglect to
consider how better land management can
reduce their impacts.
JONES. With weather events becoming more extreme our farming systems need to be more resilient. Again, this is where having carbon sequestered in soil to maintain aggregate stability and improve infiltration is vitally important.
If we look at flooding on the Mississippi, for example, we see that the mean maximum and mean minimum water levels from the early 1800s to the present show an increasing perturbation since the dust bowl era of the 1930s. That is, the highs are becoming higher ? floods are more severe ? and the lows are getting lower ? the river doesn't ?run? as much as it used to.
This boom-bust situation is due to inappropriate land management. If soil is in good condition, water infiltrates rapidly and is held in the soil profile. Some of this water is used for plant production and some will move downward through the soil to replenish the transmissive aquifers that feed springs and small streams, enabling year-round, moderated baseflow to river systems.
If groundcover is poor and soil
water-holding capacity is low, rapid run-off
not only leads to flooding in lower
landscape positions, but also takes a lot of
topsoil with it. These days it's not just
soil, but a heap of chemicals too ? which
end up in the Gulf of Mexico.
ACRES U.S.A. Causing
the Dead Zone?
JONES.
Yes. The consequences are enormous. And when
the flood is over, the river level drops
because the transmissive aquifers haven?t
been recharged.
ACRES U.S.A. Is
adding compost to the soil sufficient to
turn things around?
JONES. Compost is certainly a fantastic product, but compost alone is not enough. It will eventually decompose, releasing CO2. However, the application of compost to appropriately grazed pastures or polyculture crops can increase plant growth and photosynthetic rate, resulting in more liquid carbon flowing to soils.
Diverse microbial populations ? particularly fungi ? supported by the compost, can aid in humification, improving soil structure, water-holding capacity and nutrient availabilities.
On large agricultural holdings such as we have in many parts of Australia, it is not economically viable to spread compost. However, compost extract, which is simply the chemical signature of compost, can prove highly beneficial.
The use of natural plant or seaweed extracts as biostimulants is a relatively new but rapidly expanding area of R&D and farmer-adoption worldwide. The advantage of biostimulants is that they function at very low rates of application ? milliliters per hectare ? as opposed to a product such as compost which needs to be applied in tons per hectare.
These products stimulate soil biota and
enhance plant root function. The
proliferation of roots is quite obvious when
you dig in the soil. There can also be rapid
improvements in soil structure.
For more information about Dr. Christine Jones visit www.amazingcarbon.com
The above article by Dr. Jones gives some wonderful principles for successful farming. Now we would like to share with you why MycorrPlus is so successful in creating amazing soil, which in turn helps to improve RFV.
Dr. Jones says that the formation of topsoil
can be breathtakingly rapid. She explains
that the reason for this is that most of the
ingredients for new topsoil come from the
atmosphere, including carbon, hydrogen,
oxygen and nitrogen. Plants utilize these to
produce liquid carbon, which they then exude
into the soil through their roots in order
to feed soil microbes. It is this flow of
liquid carbon (sugars) into the soil that is
the primary means by which rich topsoil is
formed.
MycorrPlus helps to improve the soil
and the plants growing in it
MycorrPlus provides a host of nutrients, including a rich supply of the trace minerals found in ocean water. These nutrients supply the soil with what it needs so that it can supply plants with the energy they need to reach their maximum potential.
MycorrPlus
stimulates beneficial aerobic bacteria
and mycorrhizae fungi. These
micro-organisms help to create balance
in the soil. Balance
is everything! The
balance created causes the soil to
possess a high energy level.
When this energy is made available to
the plants, it energizes them
to sequester sugars to feed the
micro-organisms in the soil.
As the micro-organisms are nurtured and fed by the plant, they in turn make nutrients and energy available to the plant. This enables the plant to sequester even more sugars into the soil. This relationship between microbes and plant result in plants being able to attain their optimum potential.
Many scientists have confused themselves ? and the general public ? by assuming soil carbon sequestration and the making of topsoil occurs as a result of the decomposition of organic matter such as crop residues.
In stark contrast, Dr. Jones points out that
most of the elements needed to create
topsoil are found in the atmosphere and that
the creation of new soil centers around
carbon. Compost may help, but it is simply
not the best way to create topsoil.
A plant can acquire between 85 to 90 percent of the building materials it needs from the air to create liquid carbon. The rest of the nutrients are provided from the soil. Soil microbes use this liquid carbon as an energy source to help them convert tied up nutrients into available plant food. In the process, the sugars emitted by the roots act as a glue to create complex soil structure, which includes stable forms of carbon and humus.
New topsoil is rapidly created in this
environment. Once MycorrPlus is
activated with at least 1.1? of moisture and
a soil temperature above 45 degrees, almost
immediately plants begin to secrete liquid
carbon into the soil, and it is only a
matter of weeks before new soil begins to
form.
This is superior to results seen by using a
bio stimulant, including natural plant or
seaweed extracts. MycorrPlus
contains micro and macro nutrients
needed by the plant, plus mycorrhizae fungi, over 70
strains of aerobic bacteria that help the soil to convert nutrients tied
up in the soil into available plant food.
Carbon is needed for soil structuring and
water holding. As liquid carbon streams into
the aggregates via the roots or fungal
linkages, it enables the production of glues
and gums that hold soil particles together.
Establishing a good soil structure enables
nitrogen-fixing bacteria to function. You
will rarely see a nitrogen deficient plant
in a healthy natural ecosystem. Ammonia that
is fixed from the air is rapidly converted
into an amino acid or incorporated into a
humic polymer. These organic forms of
nitrogen cannot be leached or volatilized.
With rapid carbon sequestering, the growth
rate of plants can quickly increase. That is the power of properly
functioning soil.
Dr. Jones states that, when transitioning
between a chemically intensive system and
one dependent solely on a functioning
plant-microbial bridge, there needs to be a
transition period of 3 years or more,
reducing nitrogen fertilizer by 20% the
first year, 30% the next year and 30% the
third year.
MycorrPlus may actually be able to
reduce this transition period to one year.
Once MycorrPlus has been activated, a
plant-microbial bridge is quickly
established. The plant secretes sugars to
the soil, and harvests the nutrients it
needs. Within less than a year, nitrogen
fixing bacteria should supply all the
nitrogen needed.
Dr. Jones mentions that foliar applications
of trace minerals can help in the transition
from a chemical program. For higher dollar
crops, MycorrPlus F can be applied as a
foliar application to meet this need.
As plants
photosynthesizes faster, they are going to
have higher sugar content and a higher Brix
level. Once Brix gets over 12, the
plant is largely
resistant to insects and pathogens.
As
Dr. Jones pointed out, if plants can obtain
phosphorus and potash easily, they will
stop pumping carbon into the soil to support
their microbial partners. This interruption
of the carbon flow to the soil reduces
aggregation and the forming of new topsoil.
However, grain plants like corn or
wheat will usually need extra nitrogen.
As
Dr. Jones stated, including some clovers or
peas with your wheat or some vetch with your
corn is another way of supplying the soil
with extra organic nitrogen. As is mentioned
in her article, in biologically active
soils, Dr. Jones found the use of NPK
to be counterproductive.
Remember that a soil test can only tell you
what is available to plants by passive
uptake of inorganic nutrients. The other 97
percent of minerals, those made available by
microbes, will not show up on a standard
soil test.
By
nurturing the aerobic microbes in the soil,
we can increase the availability of a huge
variety of minerals and trace elements ?
most of which are not contained in
fertilizers.
Keep the soil covered and minimize tillage
Tilling the soil or allowing soil to remain
bare for a number of months disrupts soil
microbial life, as well as mycorrhizal
fungi. Plant a cover crop and use companion
crops with cash crops. Remember, plants
colonized by mycorrhizal fungi can grow much
more robustly even though they're giving
away as much as half of the sugars that they
make in photosynthesis through their roots.
They photosynthesize faster, producing more
sugars, which can in turn be shared with the
soil.
In regions with a hot, dry summer,
evaporation is enemy number one. Bare soil
will besignificantly
hotter and lose more moisture than covered
soil. Aggregates will break down unless the
soil is alive. Aggregation is absolutely
vital for moisture infiltration and
retention.
Minimize chemical applications
This includes fungicides, insecticides and herbicides. It
is a no-brainer that something designed to
kill things is going to do just that.
Chemical applications can inhibit the soil
fungi that are essential to crop nutrition
and soil building. When soil fungi are kept
from functioning properly, plants can no
longer use them to obtain the trace elements
they need to fight fungal diseases.
M
Click here for an article highlighting the need and benefits of building more carbon in our soils.
