Anne Bikle & David Montgomery | The Dirt Trilogy | Soil Not Oil

good evening I have the tremendous honor of introducing our next speakers David R Montgomery is a MacArthur Fellow and professor of geomorphology at the University of Washington he is an internationally recognized geologist who studies landscape evolution and the effects of geological processes on ecological systems and human societies author of three award-winning popular science books he has been featured in documentary films network and cable news and on a wide variety of TV and radio programs including Nova PBS newshour Fox & Friends and all things considered when not writing or doing geography geology he plays guitar in the band big dirt and B clay is a biologist whose wide-ranging interests have led her into watershed restoration environmental Planning and public health an engaging speaker on public health and the built and natural environments she has also worked extensively with community groups and nonprofit organizations on environmental stewardship and urban livability projects she spends her free time out in the garden with her hands on plants and dirt they're married they live in Seattle and they have a dog named Loki who apparently is a guide dog dropout and finally they do have books available in the back lobby after the talk thank you so much it is my pleasure to welcome to the soil not oil stage David R Montgomery and Ann B clay [Applause] great thank you for the introduction and just for the record I'm Dave and not Ann and and the way this is gonna work is I'll get the first half of the talk and then I'll hand off to Ann for the second half of the talk because when we talk at the same time things can get a little muddy we appreciate the invitation to come back to soil not oil and to talk about what Ann and I call lovingly our dirt trilogy the three books that we've written about soil we didn't start thinking we would write three books about soil I basically started with that dirt book about ten years ago before a lot of people are really talking about the idea of soil health and it looks back at the history of how soil degradation undermined societies around the world time and again through history so if you're a history buff that's kind of how why somebody like me a geologist would get really interested in soil looking at how the erosion and degradation of it affected human societies that middle book the hidden half of nature that Ann will talk more about in a few minutes was when we wrote together that looks at the way microbial life influences the fertility of land and the parallels between what goes on in the root around the roots of a plant and in our own guts the way that nature is actually working in terms of microbial life supporting the health of higher organisms and the third book growing a revolution is the one that's most recent and it basically takes the lessons of that first book the science in the second book and looks at the problem of how could you apply that to building a truly regenerative style of Agriculture that could rebuild the health and fertility of our land while at the same time maintaining intensive farming practices so that's why a geologist like myself and a biologist like Ann would write about soil because we sort of had this personal journey of discovery and unfolding that played out now where a lot of it started for me at least was in thinking about the degradation of land and this shows you the reason why a geologist like myself would be concerned about the state of the world soils because this is the un's map global map of soil degradation from a few years back and I like it because it's colorful its global and an awful lot of orange and red on that map there's a lot of areas where the world's agricultural soils are degraded or very degraded by some estimates we've degraded about a third of the topsoil that we inherited at the end of the last ice age coming into the world of the in between ice ages that we know in the geological profession as the Holocene are sort of the modern age of climate think about that for a minute we've decorated about a third of the landscape so far that's sort of you know disturbing enough but if you look at the one that one of the most recent reports on the global state of the soil which for this group should be of great interest there's this wonderful or horrible depending how you look at it quote from the UN global state of the soil assessment that each and every year we're losing about 0.3 percent of our global agricultural production capacity our ability to feed ourselves to ongoing soil loss and soil degradation now 0.3% is not a terribly big number but play that out over the next century over the next hundred years were on track to degrade another third of our ability to feed ourselves where our population is projected to rise by 50% those curves are working against each other and it's my contention that agriculture needs to change this century we need to not repeat the lessons I will tell you about from societies around the world that degraded and lost their soil and it's sort of no mystery that soil erosion and soil degradation helped undermine ancient civilizations if you actually dig back into the archaeological literature there's a lot of support for the idea from ancient Mesopotamia from Neolithic or Bronze Age Europe from the American South from Central America from the original agricultural lands in in China there's examples from all around the world and it wasn't deforestation that did the damage that's what you usually find when you read an environmental history textbook but I come from the Pacific Northwest where I've studied erosional processes and in forestry for in many years now and you can get erosion being accelerated when you cut trees down but they grow back pretty fast and what I basically found in researching the dirt book was that there was a different call that actually undermined the stability of many ancient societies and that culprit was the plow it was tillage that was actually the culprit that caused the erosion that so impacted the ancient world now how does that work what does tillage do when you think about it it lays the soil bare and vulnerable to erosion by water by wind how many of you have ever gone out into a native grass lender native forests and seen vast tracts of bare earth the way you do after how you would on a freshly plowed field it just doesn't happen nature clothes yourself in plants unless you go above the Timberline where you go to the Arctic or other places where plants have a really hard time establishing or a freshly deposited sediments in a floodplain which we'll get back to in a little bit but in any case this image that's up on the screen now is the first image that we have of a plow it bass it's from ancient Sumeria it's and it's not actually space aliens and Yama's it's Sumerians and livestock with the plough and basically the problem with tillage is it leaves the land vulnerable to erosion by wind or rain and it causes erosion to proceed faster than the soil can rebuild and any system that you're losing something faster than you're replacing it means you're running out of the thing of interest it's the same thing that happens to our bank accounts if we spend money faster than we make it we're burning up our savings and you can think of soil healthy fertile soil as the capital that runs agricultural enterprises human civilizations and if we are losing it faster than we're replacing it we are literally running out of it and I'm not saying that we're gonna run out of soil we're gonna run out of dirt but what I am saying is that the pace that we're losing it so exceeds the pace that is being made that it is going to become an increasingly difficult challenge to feed ourselves unless we turn that problem around and I started out as a bit of a pessimist on this issue when I wrote the dirt book I'm happy to say I'm much more of an optimist today but we'll get there the first half of this talk first third of this talk is the depressing part because when you look back through history it is a depressing story that we can find in many regions around the world there's a few exceptions there's Incan terrace terraces that are that still farmed fifteen hundred years later we're the soil quality is better than on the native hillsides how do they do it in much the same ways that will talk about regenerative farmers are doing it today many of the lessons that we can actually learn about how to rebuild soil fertility are not new lessons they're taking old ideas and bringing them into a modern context so one example that I'll show you is from the American southeast because this this noodle here this great noodle running from Virginia down to Alabama is the hill country or the upland country the Piedmont that was intensively has been intensively farmed now for about 300 years and what this shows you is the amount of topsoil that's been lost across this region compiled by fellow geologists notice it's gray four inches or more more than 10 inches in some places have been lost in the last few hundred years of post-colonial colonial and postcolonial agriculture how big a deal is that well the original journals that I can find of some of the early inhabitants of this area on farms basically described six to 12 inches of rich black earth over the reddish subsoil we've wrote it off a third to all of the topsoil across this region and we've done it in just 200 years that puts into perspective what the Romans could have done with an 800 year run at Central Italy when they undermined their own civilization what the ancient Greeks did in southern Greece with a thousand-year run at their landscape it starts to put into perspective the idea that loss of the topsoil across broad regions of terrain is not the crazy ravings of a professor it's actually something that you can go find in the record that's written on the land and reconstruct what does it look like today this shows you sort of two soils from that area that gray noodle that I was just showing you for it's from North Carolina this soil here is from a tobacco plantation and you'll notice that it looks kind of like khaki beets and it kind of looks like the California beets and I grew up visiting just south of here and there's a reason for that it is beets and it's Maya seen aged beasts and it's ten million year old beats and what makes it look like beets and there's no organic matter you go into the forest right next door where there's trees that are about you know just shy of a meter in diameter where the forest has been growing back for about a hundred years because the farm next door had been abandoned and you have soil that looks like this it's rich chocolate brown it has organic matter there's life that you can see moving in it there was no life that we could see when we dug that hole in the tobacco plantation field what's the difference this has been farmed conventionally for a hundred years this is what nature builds back in a hundred years we've basically turned soils that were like this into soils are like this across the United States and indeed in many places around the world closer alright we can do that but basically this is a problem the reduction of organic matter from in the order of five to seven maybe eight percent down to less than one percent has basically sapped the fertility of agricultural land around the world and just so you're not taking my word for it there's a paper in the journal sustainability from a couple years back that basically argued that the soil organic matter content also red carbon in the soil across North America is only about half of the level that they were when they were converted from prairies our forests to farms in others we've burned through about 50 percent of our natural capital in this country so far the numbers globally are much the same we've degraded about half the organic matter content of our agricultural lands this is a problem and it's not just a North American problem how many of you had coffee this morning here sometime today anybody ok a whole lot of you this is basically the difference in soils in part of Costa Rica where I visited for part of growing a revolution where I went to visit South an area in the heart of Costa Rican coffee country and when you drive into this valley over the crest of Central America you look down at the valley bottom the rivers are flowing this color over here this orangish color what's the difference between these two soils this one is on a coffee plantation that's been worked for less than a hundred years this is the subsoil it's a noxus all for you soil scientists out there it's an oxidized soil so it's kind of reddish this is the soil that you find in the native jungle at the top of the hill next door to the coffee plantations notice that there's about a foot of rich black earth over the reddish subsoil in a hundred years of coffee cultivation they've lost their entire topsoil they now have horrible blight problems with their coffee crop in part there's a relationship there that an we'll get into more a little later the point being this is not just a North American problem and you can actually lose the topsoil in time skills that are measured in decades to a century it can happen fairly rapidly I'll spare you all the details that are laid out in the dirt book or the site of the scientific papers I published with the numbers behind this if you're really interested the references there down at the bottom and the Proceedings of the National Academy of Sciences but one of the things I did is tried to compile the data on how fast of the world's top soils a road and how fast does nature build soil and those numbers are really different at the top basically I compiled data from I was it was something like 900 different studies the average rate of topsoil erosion off that I could find off of conventionally managed conventionally tilled farms was about a millimeter and a half a year that means it takes about less than 20 years to erode an inch of soil at that pace it's kind of a slow pace when you think about it on a day-to-day basis year to year basis but from a geological basis that is screamingly fast why because if you look at how fast nature makes soils the average number I came up with globally was about 2% of a millimetre year in other words it would take about a thousand years to make for nature to make an inch of soil this is the depart where you can get really depressed because we're roading soils a lot faster than nature can make them back as we'll see there's a way to get around this but we're not quite there yet because basically what I've just shown you is the data that it would take to actually have you calculate for yourself with the longevity of an agricultural civilization would be so if you basically take that net loss of about a millimeter a year and I'm being conservative because as I could argue for a millimeter and a half based on the global average but let's be conservative if you lost a millimeter a year of soil it's like your thumbnail thickness a year of soil regularly off fields you could burn through a half metre to one meter thick of basically a foot and a half to three foot thick soil profile it only take five hundred to a thousand years the thing that I realized in researching the dirt book was that the average longevity of agricultural civilizations was about a thousand years plus or minus 50% and in geology plus or minus 50% is actually pretty good unfortunately this example is pretty bad because if you go and you look at the average longevity of agricultural civilizations and it pencils out to be about what it would take to lose the soil through tillage you start to put these pieces together and go oh we have sort of a big long scale slow-moving problem here now I also hope you're sitting there asking yourself well but but Dave what about these other places where they people have farmed for thousands of years like the Tigers and the Euphrates in Mesopotamia like the Nile in Egypt the Indus and the Brahmaputra in India the rivers of lowland China what are those all those areas have in common they are big river floodplains and what happens on a River floodplain it floods thank you yes it floods and does the floods bring clean clear water no they bring your neighbor's tires they bring whatever was in the river they bring silt they bring sand there's a reason that those lot those civilizations were able to farm the same land for thousands of years with methods that would left the land prone to soil erosion it's that they were geographically resilient nature healed them on an annual basis by depositing sand silt sediment how thick is a grain of sand on average it's about a millimeter thick millimeter to two millimeters thick in other words if you lay down a single grain of sand each year on a floodplain you could basically heal the damage done by plow based agriculture it's when you get outside of floodplains that you start running into problems with erosion adding up over time now this of course ends the depressing part of the talk because when it started wrestling with and what anti wrestled with together in looking at the next steps our journey was asking the question of are we sort of doomed to repeat the historical pattern of soil degradation and loss at a global scale this time this would be a terrible conclusion to come to because we don't have another planet that we can go to that we can get to in any kind of a reasonable timeframe we basically have to get it right this time at a global scale and so we asked the question of can we actually reverse the historical pattern and this is the question that we started wrestling with in the hidden half of nature the book she and I wrote together and it basically started when we bought a house in North Seattle where we live and we and as a guard she's a biologist she's a gardener it had their house had a side yard that was the perfect place we thought to actually build a garden until we stripped off the lawn that had been on it and we discovered that we had this incredibly rich fertile black earth that's the envy of every gardener no we didn't we had dirt there was not a single worm that we could find when we pulled that lawn off and you might ask why we didn't dig a soil pit and so we you know we got the Attic inspected we got the basement inspected we you know inspected that the house we didn't think to dig a soil pit in our own yard we've dug them all around the world right but we did not think to do it in our own yard really bought a house but basically and based decided to go embark on what she called her organic matter crusade where she was getting organic matter from every source that she could locate it in the city from our neighbor's oak leaves to the composted herbivore turds in the Seattle Zoo to coffee grounds from the from neighborhood coffee shops and she basically undertook the project of intensive composting and mulching that turned the soil that was like this that we started with into soil like that in less than a decade she utterly transformed the fertility of our land at a pace that blows what nature would do it at out of the water this has started as most thinking what wow we could actually makes me maybe turn this problem around we could at least do it on a yard in Seattle and it this led us into the discussions about well what is it you know she was putting out compost and mulch in the yard it would disappear over the course of a season or two and and we would add more what was it led us into the world of microbial ecology and all these creatures up here are essentially that that world of microbes that the hidden half of nature delved into because that's how we started getting into thinking about how all that compost and mulch get turned into that incredibly rich fertile soil that we ended up with and the basic answer which will not be a mystery to many of you is the soil food web things were consuming those microbes were consuming all that organic matter the worms were breaking it down shredders were breaking it down it's consumed all the way from the the compost and mulch we were adding the bacteria and fungi were consuming it nematodes and protozoa we're consuming them micro arthropods were consuming then and when you start thinking about bacteria and fungi in the soil as little fertilizer packets that when they get consumed by a larger organism that then excretes out their waste it's full of nitrogen full of phosphorous is full of the mineral micronutrients that it takes to grow new life you start thinking about the cycling of elements in the soil and see the value of organic matter as the fuel that is feeding those microorganisms that's driving the recycling and the return of the elements needed for life back into new life and we basically realized that the soil food web was doing three major things the the the bacteria and fungi and the the larger life forms in the soil were helping plants with nutrient acquisition they were helping tee up plant defenses and they were basically producing compounds that were central to maintaining plant health and I'll go into a little more about these kind of things as she goes in but basically the key here was that the plants are pushing exudates out into the soil what are those exudates well they're things that are exude it out of the roots and there are things like carbohydrates there are things like proteins there's even studies that have shown the plants are pushing or exuding fats lipids out of their roots carbs fats proteins what does that sound like cookies it's food why would plants push food out into the soil it's to feed the microbial life in the soil and they don't do it just to be nice they're doing it because those microbes do things that help the plants grow it helps the plants maintain the health and it feeds them at elements that are critical for their own development and again you don't just have to take an ax my word for it this is a study from a few years back from Japan that basically looked at phosphorus P uptake by plants these are onion plants we have onion plants and basically the control our plants that did not get any fungal Tunney fungal inoculants the the the onion plants that were inoculated with these two species over here basically as you can see here they they pulled up 10 times the phosphorous from the same soil when we tend to do soil tests in agriculture and we just basically measure the amount of plant available mineral elements whether it's phosphorus whether it's copper whether it's zinc we're just measuring the amount that's readily available in soluble and water but things like mycorrhizal fungi can actually access the unavailable part and help get them into the plants they can deliver the parts that are not readily available and never show up in soil tests this was actually a revelation in terms of how we think about how do you nourish plants because it opens the door for inoculants it opens the door for thinking about soil life as the miners and delivery vehicles for mineral elements to get them into our crops there's also studies that have come out that have basically illustrated how the over application of fertilizers destroy the microbiome ability the mic the ability of a plant's microbiome to help defend that plant against disease now it's a lot more complicated than this simplified headline that got put out but the basic point is there if we over fertilize plants and we degrade the soil life that is beneficial to our crops we basically undermine their ability to defend themselves and this increases the perceived need for in demand for pesticides these ideas are linked and that observation that Ann's activity in the garden which we'll share more with you about was central to rebuilding the health and fertility of our soil basically led us to ask the question could we do this at scale on a fully operative farms so I took time off for my job at the University of Washington to interview regenerative farmers around the world who'd already restored fertility to their land and ask well what did they do and that became the growing a revolution book and to basically cut to the chase what they all had in common whether they were in Costa Rica on small subsistence farms in Equatorial Africa or enlarged commodity crop operations in North America was that they were practicing minimal or no disturbance so some variant of no-till practices they were maintaining a permanent ground cover they were planting cover crops and they were growing more than one or two things they were growing a diversity of crops and when you think about what these three things are it's a recipe for cultivating the beneficial life in the soil it's a it's a recipe for restarting the biological mechanisms of nutrient cycling and right defense promotion and growth promotion that a healthy fertile soil naturally provides they also tend to be 180 degree opposite of what we've taught people in terms of farming for the last hundred years we've taught tillage intensive fertilizer intensive monocultures this is the 180 degree opposite and it was the common elements on all the farmer on the farms that I visited around the world and described in that book you know the specific practices that those farmers used we're all different the farmers in Africa we're not using the same practices as the farmers in the Dakotas they had different technology they had different size farms they grew different crops in different climates with different soils but they all follow the same three principles some of them even were doing a few other things this basically just shows you a few I won't I won't give you the full details about their farms I talk about them in the book but Dewayne back here from Dakota Lakes research farm in South Dakota was working with farmers who were farming up to 20,000 acres these are large operations kofi boa over here notices his hat got dirt gets oil this gentleman gets it I knew when I got out of the car at his farm I knew this guy is on it he runs the no-till center near Kumasi Ghana he works with farmers for whom the room that we are sitting in would be sort of an average to large sized farm they're feeding a lot of people off very little land but he also was following these same basic three principles in different ways Gabe brown here on the left as a farmer in North Dakota he was reintroducing a livestock as part of his operation and basically showing how different means of grazing you know engaging in this style of more intensive rotational grazing could help enhance the fertility of his land and increase the carbon content of his soils and David Brant over here on the right who's modeling his tillage radishes here was a farmer in Ohio who grows corn wheat and soybeans for the North American commodity crop markets but he also grows a very diverse mixture of cover crops in between his cash crops and you'll notice that his farmer's fields are kind of yellow they're the green stuff in those fields are glyphosate resistant weeds they cover about a quarter of some of his neighbor's fields David doesn't have any glyphosate resistant weeds he doesn't have any weeds he plants cover crops and then kills them before they go to seed and he's actually much more profitable than his neighbors that are conventional that was what started sending me into sort of an optimistic spin on thinking how did he basically get a farm going where he's using a fraction of the nitrogen a fraction of the pesticides fraction of the glyphosate fraction of the diesel and essentially growing greater harvests than his conventional neighbors he did it by converting this kind of soil into this kind of soil notice that color change it's the same kind of thing of khaki to dark brown same kind of thing added in our yard same kind of thing that was done in Reverse on that North Carolina farm this is the whole story folks basically getting organic matter back into the soil it feeds the soil food web it kick-starts that cycling and life it's the way to restore soil and these simple principles of conservation agriculture plus or minus livestock as Gabe brown had are a way to actually do that and accelerate it and just to show you one other example this is Gabe Browns soil this is the soil on his sort of the best corner of his farm where he has a market garden that has the benefit of his livestock grazing and cropping he's reintegrated animal husbandry and cropping and he's basically created this rich fertile black earth this is his neighbor's farm it's actually an organic farm there's nothing wrong with organic practices but what why is gay and Gabe is not an organic farmer why's Gabe's soil so much better than his neighbors because Gabe doesn't tell any more and when you till the soil you limit the ability to put carbon back into it because you accelerate its breakdown over time so there's room in other words in both the conventional and the organic worlds for improving our soil stewardship by enhancing the fertility of our land and improving soil quality and the three sort of key words that Anna and I came up with to describe this are ditch the plow cover up and grow diversity that minimal tillage keeping the land covered and growing a diversity of crops that's kind of the recipe add livestock if you want to accelerate it I don't think you have to have livestock to restore fertile soil but I'm not convinced now that you can do it faster if you integrate the livestock and do it correct and you do it well what are some of the benefits that can result for this well it basically the one that gave me a lot of optimism is it resulted in higher farmer profits across the board if you spend less on inputs and you grow more and harvest it's a recipe for a more profitable farm the yields are comparable you'll often hear the argument that if we go to a more environmentally friendly style of farming we'll all starve somewhere down the road the farmers I visited put you know basically put that in perspective they were all growing more than their conventional neighbors they were not all organic but I started teasing a number of them that they were organic ish that they were basically almost organic farmers I think they kind of liked that they're using a less fertilizer pesticide and fossil few use fuel use and they increase their soil carbon contents you know it varied depending on what client of climate they were in what console they had it also helped with water attention and resulted in less off-site pollution these are all good reasons any one of these would be a good enough reason to adopt regenerative practices the fact that they all line up suggests to me that we really ought to be pushing the idea that this is the agriculture of the future in a big way and I think we're basically poised for what I like to call the fifth agricultural revolution which is one based on these principles of soil health and rebuilding healthy fertile soils as a consequence of intensive culture to me that's one of the big challenges of the 21st century and Anna's going to share with you the insights that came from our experience and working through the dirt trilogy and the connections between two other things that are extremely important all right is this sound okay all right good okay here we are I hope you're all ready for the second half I guess if technically the last talk of this conference and my intent here is to keep the thinking going and keep the energy going because soil not oil is really what we all want to be leaving here thinking all right so insights I don't know how many of you noticed that the talk was titled the dirt trilogy destruction insights and cure and there's not a lot of good news stories about the environment these days but I I believe and I know Dave believes too that soil is kind of an outlier when it comes to the environment because of how relatively quickly with just a little bit of care we can we can turn this situation around as he showed you with many of these farmers and here's the big idea maybe not so big or maybe I hope it's it's been dawning on you at this event that soil health is really our health and as much as I would like to try to take credit for this big idea I'm sorry that I can't because this idea in fact it goes back quite a long ways and when there's an idea that persists through time I think that tells us several things that idea is important and that idea is most likely the truth and it begins long ago with the ancients this Cirie's the goddess of agriculture fast forward a little bit to about 2500 years ago and we although we all know the name Hippocrates we know the Hippocratic oath but did you know that Hippocrates wrote a grand treatise and the purpose of that treatise was that he was trying to tease out if you really want to find out about the health of a person what you ought to be doing is looking at the place they live the water they drink and the air they breathe and the ground or the land from which their food comes and that that idea encapsulate s' I think this this whole notion of what is the quality of the soil from which we all derive our sustenance fast forward to about eighty years ago and that idea is still well and alive in the mind of Lady Eve Balfour she is a British agronomist and she was writing this book called the living soil in the run-up to World War Two and it's a fabulous book it's it's out of print but you can still find some copies of it and her peers among them farmers and other doctors they really believed that the soil was vital to health and what I really like about this is this subtitle here they she really nails it with linking human health to the vitality the soil and so these her peers and she had this hypothesis and it went like this pretty simple kind of the kind of things Hippocrates was thinking about and it posited that if the soil health is poor that's going to ripple through to our animals and our crops and to the people that are eating those crops and animals and that was largely her long argument that she talked about in the living soil and what we know now this is also information out of Britain and it covers about a 50-year period from 1940 to 1991 and these declines here these are average declines in these micronutrients across a range of fruits and vegetables that arrow and all of those things is going down another another point that this researcher brought to people's attention was it's not just the plants but it's the animals about half of the iron at the time that this study was done and declined by over by around 50% and whether you eat meat or not that is a huge decline in a very important mineral iron right that's a part of our blood that's what carries our oxygen around in our body all right so what is going on I want to take you now on a quick little field trip through the green body of a plant and you've probably all seen pictures like this plant sketch about two-thirds of the plant body is above ground about a third of that plant body is below ground unfortunately this is actually fake news okay and the reason for that is what I'm going to go into next and there's this place it's a wild in a live place and it's called the rhizosphere and it is like the headquarters it is the center of the plant business okay if you're a plant sure you've got stuff going on up top because you need to photosynthesize and capture that carbon and turn it into carbohydrates and so on but the rhizosphere this is a place where a plant will take about 40 percent or so of all of that photosynthate that's what all of those compounds are that produces with the energy it derived through photosynthesis and Dave Dave touched on this and I'll touch on it again because it is what drives nutrient cycling health and well-being in the play it's health and well-being of the soil microbiome as well and it is in this rhizosphere that we have what I call a biological bazaar and we all know what a bazaar is it's a place of ceaseless endless exchanges and trades and what we know about the rhizosphere is that it is probably one of the grandest examples of symbiosis that we know of on this planet right around the roots of a plant and so what's happening is here's a blow-up of a root hair and these exudates are flowing out of the plant all kinds of compounds all kinds of molecules plant growth promoting hormones signaling compounds that tell the soil microbiome I've got this above ground pest that's nibbling on me and I need some help getting rid of that pest and moving it off to some other plant the soil microbiome which is simply the microbes that are indigenous to the soil around that plants roots will in exchange for getting exudates they will manufacture compounds in molecules that the plant takes back up that's what metabolites refers to this is basically you can think of it as kind of like microbe crap but it's not crap at all it is super duper valuable to the health and well-being of this plant those metabolites go back into the plant and these trades keep happening over and over and over again and so I'm sure you if you go to soil conferences at all this is really liquid carbon this is how the carbon that plants are producing these carbohydrates are taking the sunshine producing these carbohydrates turning it into a form that can flow out of their roots and feed the root microbiome and what about this what about these fetching fungi what's going on there they too are consuming exudates and because fungi are their their their body is different than bacteria they have these long long strands called hyphy and they can go far away from this root here maybe over to here and what are they doing they're fetching minerals principally phosphorus this is one of the three main things that drives the growth of a plant that's the P phosphorus so here this fungi is working working away and just like anything in this world it's having to expend energy to get this phosphorus it takes it back to the plant and in exchange it gets things that it needs primarily sugars carbohydrates so this is what I mean when I'm talking about a grand grand symbiosis and from what plant biologists know now we probably know sort of the tip of the iceberg of all of these connections and what this really tells us is that plants are utterly different than than us we know that already but I really like to think about this as the center of plant intelligence it's not like us where our brain is up here on top of the body the brain of the plant is in its root system and that root system and the relationship with the microbiome the soil microbiome is really a part of the plant intelligence system and that makes the brain down here alright and so what do we know about brains we know that what we eat affects our brain and that is also the same for the botanical world brain food matters a lot why okay there's three treatments shown up here I'll let you look at this one of these treatments is absolutely nothing was done these are tomato plant roots the other treatment was conventional fertilizers and the third treatment was composted manure so which is which here you can see this is a robust healthy root system imagine the exudates pouring out of that root system imagine the soil microbiome slurping up and consuming all of those things and imagine the intelligence that's going on between that particular tomato plant and its microbiome this on the other hand is a conventional root system there's just not much going on there at all and so you have kind of a dumb plant alright and what happens when you have a dumb plant is you need to swoop in with all of these other things all of these other inputs to compensate for the loss of the biology the loss of the intelligence and so what are those inputs it's all of the stuff that that can be quite detrimental to the environment to us even to the plants themselves and that is all of the bio sites the pesticides the herbicides and so on now this is pretty interesting it's not half bad to just let a plant grow like it's always grown what we think about you know gardeners and farmers is oh my god the botanical world without us it will die but that's not the case at all look around at all the native plant communities all the vegetation that's cloaking this planet that is not tended by farmers and gardeners that's because they are relying on this ancient ancient symbiotic relationship with the soil microbiome ok and so when you really think about it plants to have a diet that diet comes from the soil and you can have a fertilizer diet and you can get buckets of NPK on a fertilizer diet and this puts biomass on a plant like crazy ok this is like a bodybuilder eating nothing but protein and steroids and you get growth growth growth but do you get health that is another question and so when you have the soil health diet sure there's n P and K in compost in all kinds of organic matter it's just slower to release you need the microbes there to help get it into a soluble form so the plant can take it up you get bucket loads of micronutrients what kinds of things iron copper zinc magnesium all of those things that are in plants and look at this the size of this aero bucket loads of beneficial microbial metabolites so that is the reason why a plant's diet matters all right the soil soil life diet versus the fertilizer diet and I want to move now because you're maybe thinking yeah wow I never knew all that about plants were you wondering what about your own body what about us mammals us human beings do we have a microbiome we do and so does everything else every farm animal everything living in the ocean in a forest pretty much every living organism has its own microbiome and this is one of this is an emerging area in science and we we used to think in particular for human beings oh it's just us us and all our human cells and we now know that that is far far from the case there's actually just as many mmm microbial cells as our own cells and maybe upwards of three times as many microbes inhabiting the inside of our body in the outside so we know that micro biomes are very important for health and well-being both it can be beneficial and detrimental and where is most of our microbiome it's sitting down there in the lower most reaches of our digestive tract in the colon you really need to think of your digestive tract in fact your whole body is kind of an ecosystem and there's different habitats and different microclimates and all of these nooks and crannies and that's where members of the microbiome live now one reason the lion's share of the human microbiome is in our gut is that there are a lot of nutrients in the gut obviously it's where all of our food ends up is in our gut and bacteria they might not have brains but they are not stupid and every life form on this planet knows through its own sensory systems where there is food and where there's nutrients and that is what they will move toward and so this is just a feature in the human colon that's called a colonic crypt and for a long time human by people who study human biology thought there's no way there's no way that any bacteria are this far down into the digestive tract that would make our immune system go berserk well it turns out that's probably not the case they're there they're very much probably our bacteria and other members of our microbiome down there so this is a cross-section through the colon wall and what's interesting I put this on here because I want you to notice that these are immune cells they are clustered just on the outside of the colon wall so you have two things going on with the human digestive tract the lion's share of our microbiome the lion's share of our immune system and some say also an awful lot of our nervous system tissue so you have this imagine this is giant Venn diagram going on around the digestive tract so this is another form of symbiosis this is another form of intelligence and information exchange and I want to now sort of pivot to another insight so what does this all mean then if we've got these symbiotic relationships that are driving our health and our well-being and we have all heard this right you are what you eat but when you think about things I think it really calls this saying into question because I'm not really sure that we are we eat and I'm gonna share that with you now when you use this as an example phytochemicals phytochemicals are naturally occurring compounds in all plants they help plants survive and deal with the challenges of being stuck in place and dealing with sunshine heat freezing insect herbivores clumsy people who step on them what have you phytochemicals are like the pharmacy the medicine chest and the Arsenal for the botanical world and without them plants would not make it at all and it turns out that phytochemicals they're also in crops in fact lycopene is found in tomatoes it's a type of carotenoid so for a feign that is abundant in our brassicas and curcumin here is in a root that is the active ingredient in turmeric so we have the fruit we have the leaf and we have the root of a plant and this is just one example there are thousands of phytochemicals in plants and the reason I'm talking about this is that these phytochemicals in our plant foods are embedded in the fibrous the fiber part of a plant food also known as cellulose and this is what our gut microbiota thrive on we take in a tomato or a kale leaf that ends up poorly digested because we don't have the enzymes to do that in our colon and that's where the microbiota get to get to work on it and so they begin to ferment these phytochemicals and they produce all kinds of metabolites they're in our gut and they there are receptors on our gut cells for either phytochemicals or the metabolites that our microbiome is generating from when they eat these fight chemicals and what these metabolites do is they interface with both nervous system and endocrine cells that are lining our gut and they will do things like stimulate the production of serotonin which is a neurotransmitter and you may be thinking wait a minute I thought that had to do with my brain it does have to do with your brain but more serotonin is made in the gut than anywhere else in the body it leaves the gut makes its way up to our brain and serotonin has a huge role in determining whether we're happy whether we're sad and those kinds of things so very much the microbiome is a part of human health as well so how do we make sure that our plant foods are dense with phytochemicals dense with these micronutrients we need to have a functioning biological bazaar that's the bottom line here and we know that AG practices as Dave talked about have a huge influence on the functioning of this biological bazaar because when you when you farming and gardening is this balance between us stepping in to try and move things along but also understanding enough about a plant's green body and what it can do on its own and more and more these days we really should be stepping back and letting this marvelous green body of a plant do what it already knows how to do that's the problem with the human brain which is so busy and active is we think we can do better and better and better so the name of the game here is a functioning biological bizarre so that we get the highest levels of nutrients in our foods that we can because of how important that is for our health and so that adage you are what you eat no we are all plus our crops and our animals we are all what our microbiomes eat that is really the take-home here so what evidence is there for this what is what evidence is there that farming practices affect phytochemical levels in crops this is a study and it was it's a review study and they found antioxidants is another word for phytochemicals phenolic or a type of phytochemical and they found more lo and behold in organically produced fruits so what does this mean in plain language we know that phytochemicals in human health are hugely important we know that they are our body's way of using our diets to undertake disease prevention right there in our guts that is what is happening when we eat nutrient-dense foods and that's why it's so important that we pay attention to AG practices because we want these robust root systems talking with the soil microbiome using all that plant intelligence all right because I think we can really turn this around we can take Balfour's idea and we can get healthy soil again we can turn our crops and our animals around and that can have a huge influence on human health and the key to all this of course is microbiomes there are parallels key parallels between the root and the gut when it comes right down to it nutrient acquisition Dave talked about that these microbial metabolites okay there is you know if these pharmaceutical companies could get their hands on the chemistry and the biology that is happening in the rhizosphere in the gut that would be well profitable for them it would also be amazing but I'm here to tell you we all have an on board pharmacopoeia already it just happens to be alive and it consists of microorganisms alright so just think about that and these things are key to our immunity and defense in the human body or the plant body this has a ton to do with intelligence I would contend all right so back to the start soil health is indeed our health and I think in all this talk that we have heard for a long long time nobody is talking about soil health being a form of a health plan for us and I think this is what we really all need to be talking more about especially this time we've got a presidential election coming up we've got Secretary of Agriculture Secretary of Health and Human Services to those two bodies talk is agriculture policy at all related to health policy I see heads shaking out there but my head is going to go like this because we need to get those two things talking yeah absolutely okay and so that brings us back to the dirt trilogy from destruction some things Dave talked about we've got these insights now about micro biomes about how they influence the health of crops and animals and that my friends is the cure all right I thank you for your time and attention and David and I will be out there and maybe we'll take just two questions thank you yeah sure yeah so the question was we need organic inputs to get the soil back up on its feet and is there an issue with not having enough organic matter to get this going again and I think that all depends on your approach and your soil and what region of the country you're in cover crops are one of the best things especially if you're any kind of production farmer at all you're you're not only getting the exudates that those cover crops are putting out that's one form of carbon and the other form of carbon is mulch you're actually getting the the physical matter and that is feeding the soil microbiome so without cover crops I think you're gonna be behind I think that's absolutely essential for those who can and want to to get animals into their system I think it's Gabe brown who says oh well the cow the cow is just pre digesting all of that stuff for you and it comes out you know half-digested which means it's feeding the soil microbiome that much sooner plus it's growing all of this protein so I think cover crops I would just say are essential for organic matter renewal sure yeah let's yep yeah so yeah so the question wondering are the agencies that deal with agriculture and health in on any of this up on any of this is it being translated is it making as a science making its way into policy and that's a slow Road and it's there's an awareness the awareness has grown hugely about the importance of micro biomes I think getting that translated in to policy is slower unfortunately I think there's something you know we all know about the US Dietary Guidelines these come out every five years they are now reaping those and primarily what that looks at is what is the food that we're eating is it a carbohydrate a fat or protein and so on and what kind of a diet should we have there is little attention in the dietary guidelines to how that food is grown and that is critically important to our health so that that would be one policy area one suggestion for anybody out there who moves in those circles that would be a great a great place for that policy as would getting some health policy some health considerations into our AG policy for example we're all urged to eat fruits and vegetables right a lot of them but do we even have enough farmers growing fruits and vegetables such that if we all were to eat according to these guidelines would there be enough so I think that's a little bit of a mismatch that I'd like to see addressed to and I see Dave just picked up the backpack out there so we are happy to field any more questions out there and thank you again [Applause]

Channel: Soil Not Oil Coalition

Views: 3,320

Rating: 5 out of 5

Keywords: Soil Not Oil, Vandana Shiva, Biosafety Alliance, SNO Conference, #environment, #ecology, #agroecology, #regenerativeagriculture, #agroforestry, #climate, #climatechange, #commons, #sanfrancisco, #earthcare, #conservation, #environmentaljustice, soil, organic, microbiology, microbiome

Id: tJh30x2b95Y

Length: 60min 45sec (3645 seconds)

Published: Wed Oct 09 2019