SOS: Save our Soils Dr. Christine Jones Explains the Life-Giving Link Between Carbon and Healthy Topsoil
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INTERVIEW
SOS: Save our Soils
Dr. Christine Jones Explains the Life-Giving
Link Between Carbon and Healthy Topsoil
To the pressing worldwide challenge of restoring soil carbon and rebuilding
topsoil, the Australian soil ecologist Dr. Christine Jones offers an acces-
sible, 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 remark-
able benefits for biodiversity, carbon sequestration, nutrient cycling, water
management and productivity. After a highly respected career in public
sector research and extension, in 2001 Jones received a Community Fellow-
ship Award from Land and Water Australia for “mobilizing the commu-
nity to better manage their land, water and vegetation.” Three years later
she launched Amazing Carbon as a means to widely share her vision and
inspire change. Jones has organized and presented workshops, field days,
seminars and conferences throughout Australia, New Zealand, South Afri-
ca, Zimbabwe, Europe, the United States and Canada. Last year, she gave
presentations to American organizations and institutions as diverse as Ari-
zona State University, NRCS, Pennsylvania No-Till Alliance, the Massa-
chusetts chapter of Northeast Organic Farming Association (NOFA), San
Luis Valley Soil Health Group and the Quivira Coalition. In 2015 Jones’
personal commitment to make the biggest possible impact globally will take
her to Alberta, Saskatchewan, Manitoba, Ontario, Kansas, New Mexico,
California, Florida, Costa Rica and South Africa, as well as many regions
within Australia and New Zealand. In early March she travels to Western
Australia, 2,500 miles from her home, to hold the first in a series of Soil
Restoration Farming Forums, in which 11 farmers will receive monetary
awards for reversing soil deterioration in dryland cropping systems through
intercropping with perennial warm season grasses.
ACRES U.S.A. You’ve written that describe the formation of topsoil as
Dr. Christine Jones the most meaningful indicator for the being breathtakingly rapid.
health of the land and the long-term
wealth of a nation is whether soil DR. CHRISTINE JONES. People
is being formed or lost. Yet there’s have confused the weathering of rock,
a widespread belief, actually dogma, which is a very, very slow process,
that the formation of soil is an exceed- with the building of topsoil, which
ingly slow process. Even some organ- is altogether different. Most of the
Interviewed by Tracy Frisch ic researchers accept that idea. You ingredients for new topsoil come from
3the atmosphere — carbon, hydrogen, bon, to signal to microbes and to other in cellulose, lignin, starches, oils, waxes
oxygen and nitrogen. plants. But perhaps the most significant or other compounds formed by plants,
finding, at least from a human perspec- microbes have to break this material
ACRES U.S.A. Why have many soil tive, is that the flow of liquid carbon to down — the same as we do when we
scientists denied the phenomenon of soil is the primary pathway by which digest starches or proteins or anything
rapid soil-building? new topsoil is formed. else of plant or animal origin. We
breathe out more CO2 than we breathe
JONES. Because they do their research ACRES U.S.A. All of which revolves in, because as we utilize the energy we
in places where it’s not happening, around the concept of a plant-microbi- obtain from the assimilation of food,
where the carbon is running down and al bridge? our cells release CO2. The decompos-
the soils are deteriorating. We need ers in the soil are doing exactly the
to measure carbon on farms where JONES. In order for carbon to “flow” same thing — breaking down organic
soil-building is occurring and see what to soil, there has to be a partner- materials and releasing CO2. These
the farmers and ranchers are doing to ship between plant roots and the soil processes are catabolic. Conversely,
make that happen. microbes that will receive that carbon. the formation of humus is an anabolic
Somewhere between 85 to 90 per- process, that is, a building-up process.
ACRES U.S.A. The process of fixing cent of the nutrients plants require for Rather than sugar being the end point,
carbon in the soil seems to be the crux healthy growth are acquired via car- sugar is the start point. Soil microbes
of your work. You describe a cycle bon exchange, that is, where plant root use sugars to create complex, stable
with carbon in three phases: as a gas, a exudates provide energy to microbes forms of carbon, including humus.
liquid and a solid. in order to obtain minerals and trace
elements otherwise unavailable. We ACRES U.S.A. How would you
JONES. The issue we’re facing is that inadvertently blow the microbial define humus?
too much of the carbon that was once bridge in conventional farming with
in a solid phase in the soil has become high rates of synthetic fertilizers or JONES. Humus is an organo-mineral
a gas. That could be dangerous for the with fungicides or other biocides. complex comprising around 60 per-
human species. Climate change is just cent carbon, between 6 and 8 percent
one aspect. Food security, the nutrient ACRES U.S.A. Are you observing an nitrogen, plus phosphorus and sulfur.
density of food and the water-holding increased awareness of the significance Humic molecules are linked to iron
capacity of the soil are also very potent of biological processes? and aluminum and many other soil
reasons for keeping carbon in a solid minerals, forming an intrinsic part of
phase in the soil. JONES. There is a lot more energy the soil matrix. Humus cannot be
generated through biological processes “extracted” from soil any more than
ACRES U.S.A. Your term “liquid car- than through the burning of fossil fuels. wood can be “extracted” from a tree.
bon” is such a brilliant phrase. It has Most life-forms obtain their energy
really helped me conceptualize the car- either directly or indirectly from the ACRES U.S.A. You frequently men-
bon cycle. What do you mean by it? sun, via the process of photosynthesis. tion mycorrhizal fungi in your work.
Plants are what we call autotrophs. That What makes them so special?
JONES. Liquid carbon is basically is, they feed themselves by combining
dissolved sugar. Sugars are formed in light energy with CO2 to produce JONES. Much of the initial research
plant chloroplasts during photosyn- biochemical energy. As heterotrophs, into mycorrhizal fungi was related to
thesis. Some of the sugars are used for we obtain energy by eating plants or the uptake of phosphorus. Phosphorus
growth and some are exuded into soil eating animals that ate plants. In effect, is a highly reactive element. As soon
by plant roots to support the microbes we’re running on light energy too. as there’s any free phosphorus floating
involved in nutrient acquisition. Even microbes in a compost heap are around in the soil, including whatever
obtaining energy by breaking down we may add as fertilizer, it becomes
ACRES U.S.A. I remember bringing organic materials originating from the fixed. In other words, it forms a chemi-
up the idea of leaky roots in a conver- process of photosynthesis. cal bond with another element like
sation with you and you laughed. iron or aluminum or calcium, making
ACRES U.S.A. You distinguish it unavailable to plants. But certain
JONES. At first people thought between organic matter formed by bacteria produce an enzyme called
“leaky” roots were defective. Exuding the decomposition of manure, crop phosphatase that can break that bond
carbon into the soil seemed such a residues or other carbonaceous materi- and release the phosphorus. Once
silly thing for plants to do! Then it als — and humus — which is generated released, the phosphorus still has to be
became recognized that some of the via a building-up process. I think a lot transported back to the plant, which is
exudates were phenolic compounds of times that is misunderstood. where mycorrhizal fungi come in. As
with allelopathic effects, important in our analytical techniques have became
plant defense. Of course we now know JONES. It’s a really important distinc- more sophisticated, we’ve realized that
that plant roots exude a vast array of tion, but it’s often overlooked. In order mycorrhizal fungi also transport a wide
chemical substances, all based on car- to obtain the energy that is contained variety of other nutrients, including
3INTERVIEW
nitrogen, sulfur, potassium, calcium, from the way we are used to thinking chemical fertilizer and pesticides break
magnesium, iron and essential trace about growing crops. up the mycorrhizal networks. If plants
elements such as zinc, boron, man- can obtain nitrogen or phosphorus
ganese and copper. In dry times they JONES. The point that’s often missed easily, they will stop pumping carbon
supply water. Mycorrhizal fungi can is that a mycorrhizal plant photosyn- into the soil to support their microbial
extend quite a distance from plant thesizes much faster than a non-mycor- partners. It’s taken a while for people
roots. They form networks between rhizal plant of the same species grow- to realize that plant root exudates
plants and colonies of soil bacteria. ing right next to it. The plant is able are not only important for nutrient
Plants can communicate with each to give half its energy away and still exchange, but also essential for the
other via messages sent through these grow stronger because of the symbiotic maintenance of topsoil. If carbon is
networks. Mycorrhizal fungi are both relationship with the fungus. It doesn’t not flowing to soil via the liquid carbon
the highway and the Internet of the cost the plant anything to photosyn- pathway, soil deteriorates. Carbon is
soil. thesize faster. It’s just using sunlight needed for soil structure and water-
more efficiently. Remember, plants are holding capacity as well as for feed-
ACRES U.S.A. How can something autotrophic. ing the microbes involved in nutrient
so important be overlooked? acquisition. When soil loses carbon,
ACRES U.S.A. And sunlight is free. it becomes hard and compacted. The
JONES. Much of the agricultural differences in infiltration and mois-
research undertaken in pots in glass JONES. CO2 is free too. If a plant pho- ture retention between high- and low-
houses is fundamentally flawed. Soil is tosynthesizes faster it’s going to have carbon soils are dramatic. Planetary
homogenized to remove background higher sugar content and a higher Brix stocks of fresh water are declining
noise, that is, to make the soil in all the level. Once Brix gets over 12, the plant alarmingly. More efficient water use
pots similar at the outset. The blend- is largely resistant to insects and patho- is going to be absolutely critical to
ing process breaks up the hyphae of gens. High-Brix plants have formed the survival of our species. Making
mycorrhizal fungi. In some trials the relationships with soil microbes able better use of water requires improved
soil is also sterilized to eliminate any to supply trace elements and other soil structure — which in turn requires
microbial activity that could interfere nutrients that the plant needs for self- actively aggregating soils. If aggregates
with the treatment being assessed. And defense, for its immune system. When are breaking down faster than they’re
often the soil has been stored for a long plants are able to produce high levels forming, the water-holding capacity of
time prior to the experiments, which of plant-protection compounds, the soil can only deteriorate.
means most of the soil organisms have insects go elsewhere.
died. In such an environment, plants ACRES U.S.A. How can we tell if a
are likely to respond to applied fertil- ACRES U.S.A. We tend to think that soil has good aggregation?
izer, as they have no other means to minerals in the soil are scarce because
obtain nutrients. Similarly with field most of them are not in a form avail- JONES. Dig a hole and take a handful
trials, if the soil has been cultivated or able to plants. of soil. Squeeze it gently and release.
bare fallowed, mycorrhizal fungi will If the soil is well aggregated, it will
not be there in sufficient quantities JONES. A soil test will only tell you look like a handful of peas. If the soil
for effective carbon flow and nutri- what is available to plants by passive remains in hard chunks that don’t
ent acquisition. In healthy, biologically uptake. The other 97 percent of min- break easily into small lumps, then it
active soils, we do not see a response erals — made available by microbes isn’t well aggregated.
to synthetic nitrogen or phosphorus — will not show up on a standard test.
fertilizers. If anything, the use of these By looking after the microbes in the ACRES U.S.A. What processes are
is counterproductive. soil we can increase the availability of going on inside of a soil aggregate?
a huge variety of minerals and trace
ACRES U.S.A. I’ve learned from you elements — most of which are not even JONES. The aggregate is the funda-
that plants colonized by mycorrhizal in fertilizers. mental unit of soil function. A great
fungi can grow much more robustly deal of biological activity takes place
even though they’re giving away as ACRES U.S.A. We always hear the within aggregates. For the most part,
much as half of the sugars that they story about fields that were continu- this is fueled by liquid carbon. Most
make in photosynthesis through their ously cropped or hayed for 30 years aggregates are connected to plant
roots. where the soil is so exhausted that we roots, often to very fine feeder roots,
have to add a lot of nutrients or we or to mycorrhizal networks unable to
JONES. That’s correct. can’t grow a thing. be detected with the naked eye. Liquid
carbon streams into the aggregates via
ACRES U.S.A. So we have this sys- JONES. The problem is that we inter- these roots or fungal linkages, enabling
tem characterized by abundance and rupt carbon flow with the way we the production of glues and gums that
generosity, and that’s really different farm. Cultivating the soil and using hold the soil particles together. If you
3gently lift a plant from healthy soil, most cannot be cultured in the lab. standard, but people happily consume
you’ll find aggregates adhering to the This applies to most species of mycor- it, not realizing it’s unhealthy.
roots. The moisture content is higher rhizal fungi as well. As bio-molecular
inside a soil aggregate than on the methods for detecting microbes in the ACRES U.S.A. These are great points.
outside, and the partial pressure of soil become more sophisticated, we’re How dependent is the world on the
oxygen is lower on the inside than on realizing there is a lot more life — and application of synthetic nitrogen?
the outside. These important proper- a lot more species — than we thought.
ties enable nitrogen-fixing bacteria to It has become obvious that there are JONES. Farmers around the world
function. When aggregates aren’t form- thousands of different types of bacte- collectively spend about $100 billion
ing — because of cultivating the soil or ria and archaea that can fix nitrogen. per year on nitrogen fertilizer. I’m
using chemicals or having bare soil The Haber-Bosch process, by which greatly inspired by the multi-species
for six months or more with no green we manufacture nitrogen fertilizer, is cover crop revolution in the United
plants — crops are not able to obtain a catalytic reaction requiring enor- States. Leading-edge farmers like Gabe
sufficient nitrogen. The tendency is mous amounts of energy. Yet micro- Brown, Dave Brandt and Gail Fuller
then to add fertilizer nitrogen, exacer- scopic bacteria in the rhizosphere or are showing it’s possible to maintain or
bating the situation. The application of within plant-associated aggregates can even improve crop yields while wind-
large quantities of inorganic nitrogen fix nitrogen simply using light energy ing back on fertilizer. These farmers
interrupts carbon flow to soil, further from the sun, transformed to biochem- are light years ahead of the science.
reducing aggregation. ical energy during photosynthesis and They’re building soil, improving the
channeled to soil by plant roots. infiltration of water, increasing water
ACRES U.S.A. It sounds like a vicious holding capacity and getting fantastic
cycle. ACRES U.S.A. I’m a little confused yields. They have fewer insects and
because I understood that there is a less disease. The carbon and water
JONES. Yes, the more N applied, difference between mineral nitrogen cycles are fairly humming on their
the more soil structure deteriorates and organic nitrogen. farms.
and ironically, the less N is available
to plants. You’ll rarely see a nitrogen- JONES. That’s correct. Nitrogen- ACRES U.S.A. I want to get your rec-
deficient plant in a healthy natural fixing bacteria produce ammonia, ipe for transforming terra-cotta tile into
ecosystem. When I was driving home a form of inorganic nitrogen, inside chocolate cake — that is, turning hard,
yesterday I noticed yellow, nitrogen- soil aggregates and rhizosheaths. compacted soil into loose, fragrant soil
deficient pastures on many of the dairy Rhizosheaths are protective cylinders teeming with life.
farms I passed. But in the area between that form around plant roots. They’re
the fence and the road, where no fertil- basically a bunch of soil particles held JONES. There isn’t a “recipe” as such
izer had been used, the grasses were a together by plant root exudates. You for maintaining soil aggregates (the
lovely dark green. can easily strip them off with your fin- starting point for chocolate cake). It’s
gers. Within these biologically active really just a set of guiding principles.
ACRES U.S.A. We are familiar with environments the ammonia is rapidly Soil becomes like a terra-cotta tile
Rhizobium bacteria and their relation- converted into an amino acid or incor- when aggregates break down. Hard,
ship with legumes. What should we porated into a humic polymer. These compacted soil sheds water. The
know about free-living nitrogen fixing organic forms of nitrogen cannot be amount of effective rainfall is dramati-
bacteria? leached or volatilized. Amino acids cally reduced. It’s also much harder
can be transferred into plant roots by for plant roots to grow in poorly aggre-
JONES. From an agricultural perspec- mycorrhizal fungi and joined together gated soil. The first rule for turning
tive the most important of the free- by the plant to form a complete pro- this around is to keep the soil covered,
living nitrogen-fixing bacteria are asso- tein. On the other hand, inorganic preferably with living plants, all year
ciative diazotrophs — so-called because nitrogen applied as fertilizer often ends round. In environments where the soil
the atmospheric nitrogen that they fix up in plants as nitrate or nitrite, which freezes, it’s still important to maintain
occurs as di-nitrogen (N2) and associa- can result in incomplete or “funny” soil cover with mulch or a frost-killed
tive because, like mycorrhizal fungi, protein. This becomes a problem in cover crop or better still, a frost-hardy
they require the presence of a living cattle if it turns up as high levels of cover that will begin to grow again as
plant for their carbon. These bacteria blood urea nitrogen (BUN) or milk soon as spring arrives. Microbes will
live in close proximity to plant roots or urea nitrogen (MUN). Nitrates cause a go into a dormant phase over winter
are linked to plant roots via the mycor- range of metabolic disorders including and re-activate at the same time as the
rhizal highway. infertility, mastitis, laminitis and liver plants. In regions with a hot, dry sum-
dysfunction. There is also a strong link mer, evaporation is enemy number
ACRES U.S.A. Isn’t our knowledge of between nitrate and cancer. In some one. Bare soil will be significantly hot-
these organisms pretty recent? places in the United States it is not ter and lose more moisture than cov-
safe to drink the water due to exces- ered soil. Aggregates will break down
JONES. The reason we know so little sive nitrate levels. Milk can also have unless the soil is alive. Aggregation is
about associative diazotrophs is that nitrate levels above the safe drinking
3INTERVIEW
absolutely vital for moisture infiltration JONES. Yes, I am, which is basically identifying is a faulty understanding of
and retention. why I do what I do. But I don’t say a what it means to farm well and to be
lot about that because if you start your a good farmer. What are some of the
ACRES U.S.A. OK, so that’s one. talk with “we’re all going to die from qualities that farmers think they should
cancer unless we change,” people tune have that get in the way of building
JONES. Point two is to maximize out. It’s too threatening. Most of us healthy soil?
diversity in both cover crops and cash have lost loved ones through cancer.
crops. Aim for a good mix of broad- JONES. I must admit that in the early
leaf plants and grass-type plants and ACRES U.S.A. You say it’s not just ’90s, when I first started going onto
include as many different functional the toxins in our food that are the farms that were using holistic planned
groups as possible. Diversity above problem, but the use of biocides — grazing, I was a bit shocked to see
ground will correlate with diversity chemicals that kill living organisms the number of weeds popping up.
below ground. Third, avoid or mini- — which reduce the nutrient content of These weeds would have been sprayed
mize the use of synthetic fertilizers, fun- food. And you attribute that nutrient under the former management regime,
gicides, insecticides and herbicides. It’s reduction to the inhibition of the plant- but the ranchers were saying, “Don’t
a no-brainer that something designed microbial bridge. worry. We have to pass through this
to kill things is going to do just that. weedy stage. If we spray weeds, we
There are countless living things in soil JONES. Spot on. If the plant-microbe create bare ground and the weed seed
that we don’t even have names for, let bridge has been blown, it’s not possible that’s there means the weeds sim-
alone an understanding of their role for us to obtain the trace elements our ply come back.” There’s a saying,
in soil health. It’s nonsense to say bio- bodies need in order to prevent can- “the more you spray weeds, the more
cides don’t damage soil! In Australia cer — and a range of other metabolic weeds there will be to spray.” It’s oh
many farmers plant seeds treated with disorders. Cancer is not a transmissible so true! Continually reverting to bare
fungicide “just in case.” They’re actu- disease. It’s simply the inability of our ground creates more problems than
ally preventing the plant from form- bodies to prevent abnormal cells from it solves. Those ranchers knew some
ing the beneficial associations that it replicating. To date, the response to the weeds had deep roots that bring up
needs in order to protect itself. After cancer crisis has revolved around con- nutrients. Leaving them there meant
a few weeks of crop growth, they will structing more oncology units, employ- better quality plants would eventually
then apply a “preventative” fungicide, ing more oncologists and undertaking be able to grow in the improved soil
which also finds its way to the soil, more research. The big breakthrough and replace the weeds. That is exactly
inhibiting the soil fungi that are essen- in cancer prevention will be in chang- what happened. Over the last 60 years
tial to crop nutrition and soil building. ing the way we produce our food. we’ve tried — and failed — to control
The irony is that plants are then unable weeds with chemicals. One of the
to obtain the trace elements they need ACRES U.S.A. We have plenty of exciting things about the multi-species
to fight fungal diseases. We see many evidence from meta-studies that the cover crop revolution that’s underway
examples of crops grown biologically nutrient content of produce grown in the United States is that the greater
that are rust-free, side-by-side with organically tends to be higher than the variety of plant types you use, the
rust infected plants in neighboring produce grown chemically. We also more niches you fill and the less oppor-
fields where fungicides are being used. have documentation of steep declines tunities there are for weeds. Cover-crop
There is an analogous situation with in nutrient content in a number of enthusiasts are experimenting with 60
human health. Not that long ago the foods over the last century. or 70 different species in their mixes. I
cancer rate was around one in 100. see the trend to polyculture as the most
Now we’re pretty close to one in two JONES. Yes, we’re getting a double significant breakthrough in the history
people being diagnosed with cancer. whammy. We’re ingesting chemical of modern agriculture. Even so, the
At the current rate of increase, it won’t residues, but not the trace elements first time you see a multi-species cover
be long before nearly every person will and phytonutrients we need for an or a cash crop grown with companion
contract cancer during their lifetimes. effective immune response. Plants plants, you might think, “Wow, that
Cancer is also the number one killer need trace elements, like copper and looks untidy” because we’re not used
in dogs. Isn’t that telling us something zinc, to make these phytonutrients. But to it. It takes a little while to realize
about toxins in the food chain? We’re the trace elements will not be available that having all those different plants
not only killing everything in the soil, in the absence of an intact microbial together is really beneficial. Somehow
we’re also killing ourselves — and our bridge. we have to change the image of what
companion animals. Is that what we a healthy field looks like so that when
want for our future? ACRES U.S.A. You’ve talked about people see bare ground or a monocul-
the pressure on farmers to have tidy ture, they recognize it’s lacking — and
ACRES U.S.A. Are you a cancer farms and uniformity in their fields. It that this is not a good thing.
survivor? seems like one of the problems you’re
3ACRES U.S.A. What sort of response areas. It’s a matter of dipping a toe in ACRES U.S.A. You mentioned the
are the cover crop pioneers receiving? the water. Include some clovers or peas longest-running field experiment in
with your wheat, or vetch with your North America that found that high
JONES. They’re seeing fantastic corn — just on one part of the field. nitrogen depletes soil carbon?
results. The trouble is they are not This reduces the risk. When farmers
getting the accolades they deserve. see that they’ve gained rather than lost JONES. The Morrow Plots are the
This is slowly beginning to change. yield — and that the crop looks healthi- oldest continuously cropped experi-
NRCS, in particular, are being excep- er — they will be inspired to try a larger mental fields in the United States. A
tionally supportive of these leading- area and a greater variety of compan- team of University of Illinois research-
edge farmers. Cover cropping is now ion plants next time. Another option is ers investigated how the fertilization
generating a huge amount of interest. to plant a multi-species cover crop on regimes that were commenced in these
Recently I visited Brendon Rockey, part of the land that would normally be plots in 1955 affected crop yields and
a young potato farmer in the San devoted to a cash crop. You’re excep- soil carbon and organic nitrogen lev-
Luis Valley of Colorado. Brendon has tionally lucky in the United States in els. They discovered that the fields that
increased irrigation efficiency 20 per- that a lot of farmers are experiment- had received the highest applications
cent through the use of cover crops. ing with cover crops now. Once the of nitrogen fertilizer had ended up
There is increasing worldwide recogni- diversity ramps up, the ladybirds and with less soil carbon — and ironically
tion of the fact that multi-species cover lacewings and predatory wasps appear less nitrogen — than the other fields.
crops improve soil-water relationships. and the need for insecticides falls away. The researchers concluded that adding
And after heavy rain, it’s obvious that nitrogen fertilizer stimulated the kind
ACRES U.S.A. Right, another aspect water has infiltrated better in the parts of bacteria that break down the carbon
of that abundance. of the field where the cover crops in the soil. The reason there is less
were. Gradually the changes become nitrogen in the soil even though more
JONES. If there is a bare fallow an integral part of farming — an excit- has been applied is that carbon and
between crops — or bare ground ing part, in fact. Experimentation and nitrogen are linked together in organic
between horticultural plantings such as adaptation become the norm, rather matter. If carbon is decomposing, then
grapes — soil aggregates break down. than conformity. Confidence builds, as the soil will also be losing nitrogen.
As a result, water cannot infiltrate as ways to restore healthy topsoil become They decompose together.
quickly. It remains closer to the surface firsthand knowledge.
and evaporates more readily. Lack of ACRES U.S.A. That’s fascinating. Tell
aggregation also renders the soil more ACRES U.S.A. What about fertility? me about David Johnson and what
prone to wind and water erosion. We he is finding in his research at New
have this fear that if we grow com- JONES. It’s important to cut back on Mexico State University.
panion plants or a cover crop, they’re chemical fertilizers slowly. If you’ve
going to use up all the water and been using loads of synthetic nitrogen, JONES. Dr. David Johnson is based
nutrients. We have to realize that by then free-living nitrogen-fixing bacte- in Las Cruces, south of Albuquerque.
supporting soil microbes, a diversity ria won’t be abundant in your soil. An He has discovered that the ratio of
of plants actually improves nutrient easy way to transition is to reduce the fungi to bacteria in the soil is a more
acquisition and water retention. amount of nitrogen applied by around important factor for plant production
20 percent the first year, another 30 than the amount of available nitrogen
ACRES U.S.A. In the transition peri- percent the next and then another 30 or phosphorus. Sadly, in most of our
od from a chemically intensive system percent the year after. At the same agricultural soils, we have far more
where you don’t have a functioning time as reducing fertilizer inputs it’s bacteria than fungi. The good news is
plant-microbial bridge, what are some absolutely vital to support soil biology that farmers use multi-species cover
kinds of practices that farmers can use? with the presence of a wide diversity of crops, companion crops, pasture crop-
plants for as much of the year as pos- ping and other polycultures — and the
JONES. Sometimes when farmers sible. Another way to gradually reduce ranchers who manage their perennial
realize the importance of soil biology fertilizer inputs is to use foliar fertilizers grasses with high density short dura-
they immediately stop using fertilizers rather than drilling fertilizer under the tion grazing accompanied by appro-
and chemicals. This is not necessar- seed. Foliar-applied trace minerals can priate rest periods — are moving their
ily a good thing. It takes time for soil also help during transition. These can soils toward fungal dominance. When
microbial populations to re-establish. be tank-mixed with biology-friendly you scoop up the soil, it has that
If the soil is dysfunctional, chances are products such as vermi-liquid, com- lovely composty, mushroomy sort of
the wheels will fall off when fertilizers post extract, fish hydrolysate, milk smell that indicates good fungal levels.
are pulled. If there is a failure, farmers or seaweed extract. Whichever path Oftentimes agricultural soils have no
will revert back to what they know ... you choose to support soil biology, smell or a smell that is a bit sour. Fungi
chemical agriculture. You have to wind the overall aim is for soil function to are important for soil carbon seques-
back slowly and accept that it’s going to improve every year. The overuse of tration as well as nutrient acquisition.
take time to transition. The key to get- synthetic fertilizers will have the oppo- The formation of humus, a complex
ting started is to experiment on small site effect.
3INTERVIEW
polymer, requires several catalysts, arrive in Australia talked about two ares of cropland and another 3.5 bil-
including fungal metabolites. feet of black “vegetable mold” that lion hectares of grazing land. Currently
covered the soil surface. Today our much of that land is losing carbon.
ACRES U.S.A. That is a really inter- soils are mostly light-colored. The use No doubt there will be — and indeed
esting insight. I would like to get of color to describe soils only came there already have been — endless
some perspective on soil degradation. into being after the carbon-rich topsoil arguments about how much carbon
You’ve written about how lush and had blown or washed away. It’s not can be sequestered in soil. In my view
green Australia’s landscape was at the an uncommon story. Just about every it’s not a matter of how much but how
time of European settlement in the so-called civilized, developed country many. The focus needs to be on trans-
early 1800s, land that’s now deserti- in the world has lost topsoil by one forming every farm that’s currently a
fied. How do your readers react? means or another. In the States you net carbon source into a net carbon
had your Dust Bowl, created by tillage. sink. If all farmland sequestered more
JONES. They have a particularly hard Restoring the health of agricultural carbon than it was losing, atmospheric
time believing that the southern and soils will require more than learning CO2 levels would fall at the same time
southwestern parts of Australia sup- how to minimize soil losses. We need as farm productivity and watershed
ported green plants during our hot, to learn how to build new topsoil, and function improved. This would solve
dry summers. It’s fortunate that some we need to learn how to do it quickly. the vast majority of our food pro-
of the first European settlers kept jour- duction, environmental and human
nals. George Augustus Robinson, who ACRES U.S.A. I read that in Australia, health problems. I’m disappointed to
was the Chief Protector of Aborigines, using the so-called best management see that articles are still being pub-
kept a daily journal for several years. practices of stubble retention and mini- lished in internationally recognized
Robinson was a keen observer. He mal tillage, wheat production results in peer-reviewed soil science journals —
made sketches of the landscape as well the loss of 7 kilograms of soil for every as recently as 2014 — downplaying
as describing it. In summertime when kilogram of wheat harvested. Is it still the potential for carbon sequestration
it was over 100 degrees and without that bad? in agricultural soils. Predictably, these
rain for months on end, Robinson articles fail to mention plant roots, liq-
noted green grass and carpets of wild- JONES. Yes, probably worse. I have uid carbon or mycorrhizal fungi. Many
flowers everywhere he looked. Sadly, documented evidence of 20 tons of soil scientists have confused themselves —
we don’t know what many of these per hectare per year being lost through and the general public — by assuming
plants were because we no longer have wind erosion. The average wheat yield soil carbon sequestration occurs as a
wildflowers in some of the colors he in Australia is very low, around 1 ton result of the decomposition of organic
recorded. per hectare. We lose massive amounts matter such as crop residues. In so
of soil to achieve it. The current situa- doing, they have overlooked the major
ACRES U.S.A. Could you reconstruct tion is not sustainable. pathway for the restoration of topsoil.
what happened to destroy all this lush, Activating the liquid carbon pathway
diverse vegetation? ACRES U.S.A. How much of requires that photosynthetic capacity
Australia’s farmland would have to be optimized. There are many and
JONES. European colonists brought increase soil carbon to offset your varied ways to achieve this. I have
boatloads of sheep which rapidly country’s carbon emissions? enormous respect for the farmers and
multiplied. In England you could ranchers who have done what the
have sheep in continual contact with JONES. It would require only half experts say can’t be done. If we have
the grass and it didn’t matter great- a percent increase in soil carbon on a future, it will be largely due to the
ly because it nearly always rained. 2 percent of our agricultural land to courage and determination of these
Australian weather tends to oscillate sequester all Australia’s CO2 emissions. individuals.
between drought and flooding rain and Our emissions are low in relation to
the English weren’t used to that. By the our land area because we have a rela- ACRES U.S.A. You initiated the
late 1800s there were many millions of tively small population. Australian Soil Carbon Accreditation
sheep in Australia, grazing the grass- Scheme (ASCAS). I’m quite impressed
lands down to bare earth in the dry ACRES U.S.A. Do you have any that one person started something like
periods. When it rained, the unpro- idea worldwide how much farmland that.
tected soil washed away. The river would have to be managed differently
systems and wetlands filled with sedi- to increase soil carbon sufficiently to JONES. I launched ASCAS in 2007 out
ment. We’re now farming on subsoil. reverse global climate change or offset of frustration that the federal govern-
We’ve lost around 2 to 3 feet of topsoil greenhouse gases? ment wasn’t doing anything to reward
across the whole country. The original innovation in land management. I
soil was so well aggregated that aborig- JONES. Agriculture is the major land wanted to demonstrate that leading-
inal people could dig in it with their use across the globe. According to the edge farmers could build carbon in
bare hands. The first Europeans to FAO there are around 1.5 billion hect- their soils and be financially rewarded
3for doing so. But my attempts were form mycorrhizal associations that JONES. With weather events becom-
blocked at every level, including being help them survive. The grasses soon ing more extreme our farming systems
subjected to public ridicule. I suspect create their own microclimate. It’s an need to be more resilient. Again, this
much of the resistance stemmed from absolute delight to see these patches is where having carbon sequestered
the fact that Australia was importing of green in an otherwise parched land- in soil to maintain aggregate stabil-
over $40 billion worth of farm chemi- scape. It helps us understand how the ity and improve infiltration is vitally
cals and policy-makers saw that as a big countryside encountered by the first important. If we look at flooding on
business. They realized that in order European settlers was able to remain the Mississippi, for example, we see
to build soil carbon, farmers would green over the summer. that the mean maximum and mean
need to reduce chemical use. There minimum water levels from the early
were other issues too. Australia ratified ACRES U.S.A. At the People’s 1800s to the present show an increas-
the Kyoto Protocol nine months after Climate March in New York City, a ing perturbation since the dust bowl
the launch of ASCAS. Under Kyoto large contingent of vegan activists car- era of the 1930s. That is, the highs are
Protocols, the issuance of carbon cred- ried signs blaming cattle as a major becoming higher — floods are more
its requires adherence to the 100 year cause of global warming. What are severe — and the lows are getting
rule, which basically means that any your thoughts on targeting ruminants lower — the river doesn’t ‘run’ as much
payment for soil carbon must be regis- for greenhouse gas emissions? as it used to. This boom-bust situation
tered on the land title and the money is due to inappropriate land manage-
refunded if for any reason the carbon JONES. There were more ruminants ment. If soil is in good condition,
levels fall over the ensuing 100 years. on the planet 200 years ago than there water infiltrates rapidly and is held in
Then there’s the additionality rule, are now, but we’ve gone from free- the soil profile. Some of this water is
which states farmers cannot be paid ranging herds to animals in confine- used for plant production and some
for changes in land management that ment. That changes everything. Firstly, will move downward through the soil
they would have made anyway, or that we’re growing feed for these animals to replenish the transmissive aquifers
result in higher profits. using fossil-fuel intensive methods and that feed springs and small streams,
secondly, confinement feeding creates enabling year-round, moderated base-
ACRES U.S.A. You said this story has a disconnect between ruminants and flow to river systems. If groundcover
a good ending. methanotrophs. Methanotrophic bac- is poor and soil water-holding capacity
teria use methane as their sole energy is low, rapid run-off not only leads to
JONES. Despite the roadblocks, I felt source. They live in a wide variety of flooding in lower landscape positions,
it was important that soil restoration habitats, including surface soils. If a but also takes a lot of topsoil with it.
pioneers be recognized. Late last year cow has her head down eating grass, These days it’s not just soil, but a heap
we decided to discard the original the methane she breathes out is rap- of chemicals too — which end up in the
ASCAS model and start afresh. On idly metabolized by methanotrophs. Gulf of Mexico.
March 19, 2015, almost eight years to There’s an analogous situation with
the day after we launched the ASCAS termites. Termites produce methane ACRES U.S.A. Causing the Dead
in 2007, our patron Rhonda Willson during enteric fermentation, as hap- Zone?
will present 11 Soil Restoration pens in the rumen of a cow. But due
Leadership Awards at a farming forum to the presence of methanotrophic JONES. Yes. The consequences are
in Dongara, Western Australia. It’s a bacteria, methane levels around a ter- enormous. And when the flood is
fitting conclusion that these awards be mite mound are actually lower than over, the river level drops because
presented in the International Year of in the general atmosphere. In nature, the transmissive aquifers haven’t been
Soils. everything is in balance. After the recharged.
disastrous Deepwater Horizon oil spill
ACRES U.S.A. What changes did in the Gulf of Mexico, the ocean was ACRES U.S.A. Is adding compost
your Soil Restoration Leaders make in bubbling with not only oil, but also to the soil sufficient to turn things
order to improve soil function? methane. To the astonishment of scien- around?
tists monitoring the spill, populations
JONES. The agricultural region of of methanotrophic bacteria exploded JONES. Compost is certainly a fan-
Western Australia experiences an and consumed an estimated 220,000 tastic product, but compost alone is
extremely hot, dry summer. Winters metric tons of methane gas, bringing not enough. It will eventually decom-
are cool and moist, although not as levels back to normal. pose, releasing CO2. However, the
moist as many farmers would like. application of compost to appropri-
Innovative ranchers have been plant- ACRES U.S.A. When we talk about ately grazed pastures or polyculture
ing summer active grasses at the end of the consequences of the increased crops can increase plant growth and
winter when there is sufficient moisture extreme weather associated with cli- photosynthetic rate, resulting in more
for germination, despite ‘expert’ opin- mate change, like devastating floods liquid carbon flowing to soils. Diverse
ion that it’s too hot and dry in summer and droughts, all too often we neglect microbial populations — particularly
for anything to grow. Perennial grasses to consider how better land manage- fungi — supported by the compost,
have incredibly deep root systems and ment can reduce their impacts. can aid in humification, improving
3INTERVIEW
soil structure, water-holding capacity JONES. I’ve always been in tune with to do an economics degree. Out of
and nutrient availabilities. On large natural rhythms. I grew up in a little the blue I was offered a scholarship
agricultural holdings such as we have log cabin in what Australians call the to study textiles. My first full-time
in many parts of Australia, it is not bush. Here in the States you might job after graduation involved research
economically viable to spread com- call it wilderness. On one side of our into the parameters of wool that affect
post. However, compost extract, which cabin there was a big lake. An estuary processing performance. Unless wool
is simply the chemical signature of joined the lake to the ocean, so there fibers have an even diameter all the
compost, can prove highly beneficial. was water on three sides. The fourth way along their length — and high
The use of natural plant or seaweed side was a forest filled with all kinds tensile strength — they break easily
extracts as biostimulants is a relatively of intriguing plants and animals. I was and are difficult to spin into yarn.
new but rapidly expanding area of very much a child of the earth. My dad Wool quality is influenced by pasture
R&D and farmer-adoption worldwide. said I had my own veggie patch when quality, which in turn is affected by soil
The advantage of biostimulants is that I was only two. By that stage I could quality. In a roundabout way I became
they function at very low rates of appli- also apparently catch more fish than interested in the linkages between soil
cation — milliliters per hectare — as him. I just seemed to know where the health, plant growth and animal pro-
opposed to a product such as compost fish would be and what they wanted to duction. I undertook a Ph.D. in soil
which needs to be applied in tons per eat and what time of day they would biochemistry to better understand how
hectare. These products stimulate soil be feeding. I was unaware that humans plants communicate with soil micro-
biota and enhance plant root function. over-consume resources and pollute bial communities. There haven’t really
The proliferation of roots is quite obvi- the environment until we moved to been any light-bulb moments; it has
ous when you dig in the soil. There the city when I was about eight years been an ongoing process of discovery,
can also be rapid improvements in soil old. I cried myself to sleep every night finding the miraculous in the common.
structure. because, for me, it was paradise lost.
For more information about Dr. Christine Jones visit
www.amazingcarbon.com.
ACRES U.S.A. Your orientation is ACRES U.S.A. Did you study soils
extraordinary. I’m wondering if at a because you loved to grow things?
certain point in your life, the way you
saw the world underwent a radical JONES. At school I became very
change. interested in economics and planned
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