 Well, I'd have to say it's really exciting to be here in Watertown and thank you so much to the South Dakota Soil Health Coalition for inviting me here. It's a really, really inspiring. The work that you're doing is really amazing and I do get to travel a fair bit, see a lot of different parts of the world and I'd have to say that what you're doing here really is first class so I'm very honoured to be here and to be part of it. Also to hear that the presentations that have gone prior to mine, there's one advantage of being one of the last speakers in that is that you get to have the last say but the disadvantage is that everybody else has already said it. So I have been trying to put together a few things that I hope will challenge some thinking and present a little bit of new material which, you know, in the soil health sphere it's really, it's as those of you who are on the journey which is just about everybody in this room, it is really exciting. There's new things being discovered almost every day. It's a universe really that we know very little about. People have said that we know more about, you know, the solar system and the stars and then we do know about the soil and that's very true but it's something that is changing very rapidly. We are learning a lot about soil and how soil functions and it's, as those of you who have a passion for soil health know, it's a really exciting journey to be on. So and the other issue is if I stand here, I've actually, I'm right in front of it so I either, would it be better if I stood over here? Is that good? Does that work for everybody? Okay, so let's go. So one of the things that I wanted to say, this saying actually comes from South Africa or it's not mine, but is that if you haven't discarded a firmly held belief in the last 12 months, check your polls. You may be dead. We are rapidly discarding a lot of things that we thought we knew, not only about human health but also about animals and also about the soil. So, you know, the frontiers in remnant nutrition, for example, human nutrition and plant nutrition are definitely expanding very quickly and some of us, including myself, have had to go, okay, so what we thought, you know, was how things work is actually not how it is. And one of the things that is really changing the way we're looking at the world is the technology that we now have to look a little more closely at things that in the past we were not able to see like microbes and we've realized that really it is the things we cannot see that are running this place. And the sooner that we come to terms with that and realize how powerful these microscopic little things are then the faster we will make advances in where we need to go because these little critters that we can't see are very useful for helping us achieve our goals. So a recent census of life, don't ask me how they actually measured this, they worked out, some scientists worked out that there are 550 gigatons of carbon-based life forms on planet Earth and 450 of those gigatons are actually in the form of plants, which is hardly surprising because when you do look around, you see that almost everywhere in the world that you go, there are green plants, whether that be ground covered plants or shrubs or trees that the major life form on Earth is actually plants. So that wasn't really a surprise. What I found surprising was that of the other 100 gigatons, so we have 550 gigatons, we take away the 450 gigatons of plants and what we find is of the other 100 gigatons, 93% of that is actually living things in the form that we cannot see. In other words, microscopic living things make up 93% of the other 100 gigatons and those microscopic living things are the protists and the bacteria and the archaea and the fungi that basically run our soils, run our bodies, run animal bodies, they're very, very important for ruminant nutrition as well, run our plants and we need to figure out a lot more about how they work so that we can help with all of those ecosystems and as any of you in the room who have had health challenges or know people that have had health challenges or read about human health, you'll find that almost everything you pick up today will talk about the gut microbiome and how important the microbes in your gut are for you because they run you. So you have to look after them if you want to be healthy. So the same thing goes for soil, we have to understand how the microbes in our soil work and look after them if we want our soil to be healthy because they comprise the major biomass on earth apart from plants. So if we have a look at the weight of microbes in that 93%, we see this is just a diagrammatic representation of which forms of microbes there are making that up. So the protists are there at the top in the orange, the archaea in the purple, fungi green and bacteria in the beige colour at the bottom. So bacteria make up a massive 70% of that 100 gigatons. At one time we used to think bacteria were bad because we associate, you know, they're germs and I still see, you know, the hand wash that says, you know, kills 100% of all germs or kills 100% of all bacteria. I think my goodness, you know, we are so ignorant about the fact that really 99.9% of them are beneficial and we need to have them. We don't want to be killing them all. And then we, you know, now that people have understood how important bacteria are, some people still think fungi are bad because we think of fungal diseases, but in fact 99.9% of them are not only beneficial but essential and the same of course goes for archaea and protists. What I haven't talked about and what I don't have time to talk about today are the viruses which are a magnitude of order, an order of magnitude, sorry, even more abundant than any of these other life forms. They're not considered to be living things because a virus is just a fragment of RNA or DNA. So it actually doesn't count in this graph but in reality those fragments of RNA and DNA are very, very powerful as any of you who've ever had the flu will know and viruses in fact are key determinants of the functioning of all these other microbes and larger things like animals and people. So the things that we can see, the insects, the fish, the birds, the earthworms and everything that people have been talking about over the last few days, you know the wildlife, our livestock and of course people, we make up the remaining, the things we can see make up the remaining 7% of life on earth and humans are only a tiny part of that. We actually constitute 0.01% of the biomass of life on earth and we consider ourselves to be so incredibly powerful. We have made major changes on this planet, most of them not good. We now understand why those things are not good and we are going about changing them, reversing many of the effects that we've had which is fantastic and we're using our intelligence to do that but we need a lot more than human intelligence in order to do that. We have to, if we're smart, we will engage the help of microbes to assist us in making those changes to life on earth. So there's not many of us in terms of weight but we do have some intelligence and hopefully we can use that to good ends. So that figure that I've given you there of humans comprising 0.01% of the biomass of life on earth, that's by weight. I'm not talking about numbers there, when we talk about numbers we find that the differences are even more staggering. So one teaspoon of healthy soil, those of you already familiar with this, particularly if you take it from near the roots of living plants, it will have more microbes in it than there are humans on earth and if we take a more biologically abundant environment than that, say the rumen of a cow or a sheep, one drop of rumen fluid contains 10,000 times more microbes than there are humans on the planet. So think about that, one drop one tiny drop of rumen fluid contains 10,000 times more microbes than there are humans on the planet. So it's really hard to get our head around these differences in scales between the human population and the population of other living things. And even within our own bodies we have around about one trillion human cells and 10 trillion bacterial cells. So on a cell count we are only 10% human and I think there is a book written by that using that as a title. And then if we look at our genes you know the genetic material that codes for basically everything that we do and think. We have around 300,000 human genes and about 100 times more that in bacterial genes because of the huge numbers of bacteria that we have in us and on us, in effect we're only 1% human if we look at it from a genetic point of view. And the situation in plants is exactly the same. If you look at the number of cells, living cells that there are in a plant that are actually plant and then you look at all the microbes that are on plants and in plants and around plant roots you find that plant cells are outnumbered by microbial cells. So again we look at a plant and we think what we're dealing with is the plant and plant genetics but actually what we're dealing with is the microbes on, in and around that plant. And that's the way that we have to change our thinking. As I said at the beginning if you haven't discarded you know deeply held belief in the last 12 months you know check your pulse because you have to start thinking about microbes on you, on your animals in you, in your animals and on and in your plants. That's where the future is. Thinking about that and how to manage those. So all plants and animals are embedded in a microbial world. We can't see it but it's there. And we have a microbial world embedded within us. This is actually a good thing because microbes are capable of performing all sorts of amazing tasks that we humans even though we think we're clever are not able to perform. And how do they do that? When we start looking at them we realise you know it's a tiny little thing, you can't see it. They can't hear, they can't speak, they can't see anything. I mean just close your eyes for a minute and think okay I'm a tiny, tiny, tiny little microscopic thing. I can't see, can't hear, can't talk to anybody. But there's millions and millions and billions and billions of us microbes all out there and we have to coordinate our behaviour in order to do the miraculous things that microbes do. So how are we going to do that? We can't use any of the things that more so called advanced forms of life like humans can. Mind you with all the advanced communication skills that we so call, we apparently have. Sometimes we don't do a great job of communicating do we? One of the talks that we heard yesterday Andrea was saying you know that we need to talk to each other more and communicate more and tell other humans you know about what we're thinking and what we're feeling. But microbes are very, very good at doing this. So how do they communicate with each other and how do they coordinate their activities to do the sorts of things that they do? Well they use a process called quorum sensing. How does quorum sensing work? Well we also use that term in human society if we have an organisation like let's say the Soil Health Coalition. How many members do you have, Sarah? 537, 537. Ah okay well let me go back and change that question then. How many people are on the board? Nine. Nine people on the board. So if you, nine directors on the board so if you were going to have a board meeting about something like we're going to invite this crazy lady from Australia to come and you know speak at our event and tell us we need to know more about microbes and you had a meeting about that and only one person came to that meeting you probably wouldn't actually be able to make that decision to say we're going to spend money on airfares and whatever to get that lady to come here. So you would probably have a minimum number of people on the board that would be a quorum. It's six, is it? Five. Okay so five members of that coalition would need to be present at that meeting in order for a decision to be made. If one person turns up at the meeting the coalition cannot make a decision about something. So there is a soil health coalition that is able to make decisions but they cannot make that decision unless they have a quorum of five members come, five directors come to the meeting. So those of you who belong to any kind of a group or an association you will understand how quorum works. Well it's exactly the same in the microbial world. For example we have bacteria lactobacillus in our large intestine that are able to manufacture B vitamins like vitamin B12 for example. Perfectly capable of doing that. But how many people, probably people in this room are vitamin B12 deficient. Some people go and have to have injections for vitamin B12 or take supplements for vitamin B12 or supplements for other B vitamins. I mean really if you had an lactobacillus in your large intestine to reach a quorum they would collectively then make a decision to manufacture B vitamins. But they will not be able to make that decision or switch on, what they are doing is actually switching on their genes to manufacture B vitamins. Or vitamin B12 to give you a specific example. There will be a specific species of lactobacillus that will be able to manufacture vitamin B12 but in order to switch on the genes to do that they will have to reach a quorum. And what do they need in order to reach a quorum? Well there has to be a certain number of them. So it's a population thing. So what sorts of things would prevent you from having lots of lactobacillus in your gut? Well taking antibiotics, eating meat that was produced in a confined feeding animal operation where the animals were fed antibiotics will have exactly the same effect as taking antibiotics yourself. Consuming any other kind of chemical that can affect microbes in your gut which is most of our food has some kind of chemical either added to it when it's growing or when it's in storage or when it's being processed. There's an awful lot of chemicals get added just in the food processing business and if you look at the ingredients for example in bread or any of the common things that people consume there will be what used to be in bread like flour and yeast and salt and those kinds of things that used to be in bread and then there will probably be 20 other ingredients like flavour enhancers and emulsifiers and preservatives and heaven only knows what that didn't used to be in bread 50 years ago and have a look on the packets of snack foods and see the list of ingredients that's actually there. Those things affect your gut microbiome. Those things mean that you will not have sufficient numbers of microbes in your gut to manufacture the vitamins that you need. If you go into a supermarket and you find one whole aisle will be full of supplements that people are taking all these things to try and replace what microbes in their gut should do. That's a very well known example in the human health sphere so if we look at the parallels in soil we see exactly the same thing. We are meant to have lots and lots of microbes in our soil performing all kinds of functions like manufacturing vitamins for plants for example but if we are using lots of chemicals then we will still have some microbes but we won't have enough to reach a quorum so it's that tipping point that's really important. It's like you're bored if one person or three people or even four people come to the meeting it is not enough to make a decision. So with microbes quorum sensing means that there will be enough of them to actually alter their genes or alter the genetic expression in their plant host or their animal host and this is where microbes are so incredibly powerful because not only can they switch their own genes on and off but they can switch plant genes on and off, animal genes on and off and human genes on and off. So some of the plant genes that they can switch on for example are genes for things like acquiring nutrients for being frost tolerant and that's why where we see in soils where microbes are reaching a quorum that plants become more drought tolerant, become more frost tolerant, have higher nutrient densities in them. So we're going to see if this will help in the back. What do you think? So you weren't able to hear me in the back. Sorry, I assumed that you could hear me and I didn't realize that you couldn't. Start over. Okay so this is a quick slide. Okay so just as a quick summary, microbes are really important and you have to have a lot of them and you have to have a lot of different kinds of them because they are all capable of performing different tasks. So that's one reason why we have to have a lot of different kinds of plants growing in soil because every kind of plant will support a different microbiome, we call it, of having microbes on it, in it and around it. And we need those microbes to perform very very important tasks in our soil, like switching genes on in plants, for example, for drought tolerance, frost tolerance, nutrient acquisition, also for tolerance to pests and diseases, all sorts of things like that. It's just like we see the same parallels in human health as we see in soil health. This microphone is much better. It was a shame I didn't have this one to start with. So I'm sorry if you couldn't hear what I was saying. So in the microbial world, quorum sensing, it's density dependent, it's coordinated behavior. Microbes are using these quorum sensing signals, so they're little chemical structures called auto-induces that are floating around. There's millions and millions of them floating around in the soil. Microbes having a conversation with each other. So it occurs in all species of bacteriarchia, fungi and viruses. All microbes use quorum sensing to communicate. So every species produces its own unique signal. So every species of microbe needs to know how many of them there are. Because if there's only a few, they're going to keep really quiet. They're not going to do anything else. They're not going to do anything that's going to attract attention because someone might come along and eat them. And if there's lots and lots of them, obviously they're going to be more powerful. I mean, we do the same thing to some extent. If I was up here speaking to a room full of people manufacturing neonicotinoids, for example, they probably weren't going to be too impressed about me saying don't put that on the seed because it's going to affect the microbial populations around that seed. I may not necessarily want to even get up and speak to those people. If I'm speaking to a room full of people that I know are interested in soil health, then I'm going to be able to say what I really think about soil health. So microbes are the same. They're said to be in the environment all the time. Is it safe or is it not? Should I keep quiet? So they use these autoinduces as signaling molecules. And when the concentration of those reaches a critical level, then they're able to switch on their genes to do various things or switch on the genes of their hosts. And what do they look like? Well they're fairly complex biochemicals. I'm not going to go into any detail about this. If you want to Google autoinduces, this one comes from core principles of bacterial autoinduces systems. It basically talks about gram positive, gram negative bacteria, etc. and what sorts of autoinduces that they produce. The thing about that you need to know about autoinduces is that this is a bacterial cell producing autoinduces. Every autoinduce will have its own formula which we can represent as a shape. It could be a square or triangle or circle or something. And that will fit into a receptor site in another bacteria of the same species. So when there's a whole lot of these in the environment that is how other bacteria know that there's a whole lot of them there. And then it can change its genetic experience. So this comes from an article called The Languages of Bacteria. And this lady here, Bonnie Bassler she produced a great little TED talk called How Bacteria Talk and if you want to know more about autoinduces and how bacteria speak to each other, I'd recommend. I think it's 18 minutes but the 18 minutes goes really quickly because it's a really really good little talk. So How Bacteria Talk Bonnie Bassler. So this is very similar to how we actually communicate like within our bodies how we've got a whole lot of different organs, our heart, liver, lungs, spleen, kidneys everything all actually functioning hopefully in a coordinated way to make us work as a unit. So you can't just take your heart out and your liver out or your spleen out and put it on one side and say well that's just going to work all by itself. We have to have all those things in an integrated system working together and there's lots and lots of communication going on in your body all the time with all your different organs sending out signals and speaking to each other if you like, communicating with each other using biochemical signals that fit into receptor sites in exactly the same way as bacteria communicate. So just to give you an example of that for example your pituitary gland which is located in your brain could be sending out a signal telling your thyroid to get going and get active. That will be called a thyroid stimulating hormone, TSH. That hormone is released into your bloodstream your thyroid will have receptor sites for that and will respond to that hopefully but you know your liver and kidneys and your spleen and your heart and your lungs and all the other organs in your body are going to ignore thyroid stimulating hormone because it's not for them. It's a specific shape and it fits into a specific receptor site in your thyroid. So any of you who understand about you know microbes in the human body and biochemical signals in the human body you'll know how that works. It is exactly the same in the soil. There are lots and lots of living things in the soil sending out signals. Some things can respond to those other things cannot respond to those. So it depends whether they have receptor sites for them or not. So microbes are also multi-lingual not only can they talk to each other but they can about how many others of other species and other kinds are there. So the bacteria will know how many fungi are there. For example the fungi will know how many bacteria and so on because they're all very good at picking up all these different molecules. So they know how many of us there are and how many of them they are. And I'm not going to go into it in any more detail than that other than to tell you that basically that is how soil works with microbes communicating with each other. So all plant and animal genes and human genes are influenced by quorum sensing. That is the important part. Not necessarily the science of it but the fact that and you know that genes regulate for a whole lot of different things. Genetic expression like in animals for example your livestock you know genetics is important for how fast a feed conversion efficiency and those kinds of things. Heat tolerance, drought tolerance, cold tolerance are all going to be regulated genetically as it is same in plants. So it's very very powerful that microbes are able to switch genes on and off in plants and animals. So if we actually want to use this knowledge for our benefit we have to figure out how to improve those conversations and really that's all we need to know. We don't need to know the biochemistry of it. We don't need to know the language we just need to figure out how to improve the conversation so that there's more of them and there's more things happening in the soil. So when we're standing on soil we're standing on the rooftop of another world and you're all very well aware of that. But we have to think about that as a holobiome. We've in the past always wanted to look at things in detail. So we will look at one kind of plant in detail or we'll look at one specific part of the plant in detail. Instead of realizing that the community is a holobiome but the above parts and the below ground parts and then all the microbes that live on in and around those plants that whole thing is important. So we can't go and spray some fungicide on some leaves of something without affecting everything. We can't plant a seed that's got poisons on the seed without affecting everything. We tend to look at those things in isolation without understanding the bigger effects because when we get that holobiome actually functioning as it should as a coordinated unit then everything changes. It becomes a super organism and extraordinary things happen that we don't see happen otherwise. So the things that we have to consider, again I've just said it's a holobiome now I'm going to break it into parts but the phyllosphere, which is everything that's above ground, the risosphere which is what's around the plant roots and then the endosphere which is what is actually inside the plant. So a lot of soil health has actually talked about the risosphere which is not really surprising because that's what's around plant roots and we've become very interested in plant roots and seen how many are there, how deep are they, do they have riser sheets or dreadlocks around them, is there an excitation happening around plant roots how fast are they building soil. The phyllosphere is something that's really been of more interest I suppose to people who study insects and also look at how plants communicate with insects and plants communicate with each other above ground. The endosphere has probably been the last frontier but in the last few years there's been a lot of work on what's actually going on inside plants and how are microbes working inside plants. So if we look at the, like the Holobion, I think I've got something here that's got a pointer on it. Yes, okay. So oops, pressed all the wrong things there. Dangerous with technology. So we have to look at this whole thing. So the leaves and the stems and everything, this is the above ground part, the phyllosphere so you know plants are actually going to be communicating with other plants above ground and then below ground we've got all these things that happen around the risosphere which most of you are very familiar with. We've got root exudation and we've got nutrients and chemical signaling. We've got beneficial microbes and we've got pathogenic microbes and all the interactions that go on there around the risosphere. That's something that we do know quite a lot about but the phyllosphere, if we were actually to look at that in terms of the chemicals that are there from a plant perspective you think there's just a plant sitting there or a crop sitting there or a diverse big plant sitting there and this is what it looks like from the plant perspective. They're actually picking up on all these signals all of the time that are all around them that we can't see with the naked eye. It's probably a little bit like in this room right now there's radio signals and television signals and signals from people's phones and all kinds of things that if you have a device, if you have some kind of antenna or some kind of a receptor that can actually pick up those signals you can tune into the television or tune into the radio or you could call someone on your phone right but we can't see the signals are all here in the room but we can't see them. So the next time you're looking at your crop or your pasture I think that those plants are actually growing in an atmosphere that looks like that. They know through all those signals what's going on around them and those signals can be changed by what kinds of microbes they have on their leaves. We know for example that insects are picking up on these signals all the time so if plants have a bricks level of less than 12 for example they're going to be subject to insect attack. They have a bricks level over 12, insects will just keep going and go and pick up someone else's crop. So people entomologists are very aware of these plant signals and what they mean. One example of this is that you'll see for example on this plant that the older leaves which have a lower bricks level than the younger leaves are being attacked by insects because they're giving out a different signal. So we'll see these kinds of things if you observe them. So the rhizosphere again we know a lot about that we've got the plant root over here soil particles over here and the rhizosphere is this incredible area of biological activity around surrounding that plant root. Here you see lots of hyphae of fungi some of those will be similes like mycorrhiza and trigoderma, some of them will just be sapotrophic fungi that are just feeding on these exudates which you can see little droplets of plant root exudates coming out. What you can't see even on that photograph are the billions of bacteria that are too small to show up at that level of magnification. Of course not all rhizospheres are like that that's a very very healthy one and if we're using chemicals in agriculture then we're not going to see those healthy rhizospheres because we're going to knock those microbes out and that makes a huge difference to plant health. So just to give you one example of that and something we can talk about for hours but we don't have the time. On the left here these are roots of oat plants that have been fertilised with nitrogen and this is oat plants roots on the right that have not had any nitrogen fertiliser applied and you can actually can't see the roots. They're in behind all of that those dreadlocks. So it's a high magnification photo of rhizospheres on plant roots and all you can see are the hyphae of beneficial fungi. You can see all kinds of glues and gums that are sticking all particles together making the plant much more drought tolerant because it holds a lot more moisture around the roots creating air spaces and creating spaces for water. This poor plant has got no microbes to help it to obtain any of the things that it needs certainly won't be fixing any nitrogen. There's lots of free living nitrogen fixing bacteria here fixing nitrogen for this plant. So this are the things that we inadvertently do in agriculture. We don't realise. So when I say chemicals I don't just mean fungicides and insecticides I mean we've got to look at the effect of high analysis fertilisers on plant roots. And then the endosphere. Well the endosphere is what happens inside the plant endo means in. So we have some well known plant symbiotes that live partly outside and inside plants like mycorrhizal fungi and nitrogen fixing bacteria that live in nodules on plant roots. So you know we've seen lots of examples and there are people in the room I know who actually do microscopic examination of their plant roots to look to see are there are bascals of mycorrhizal inside my plant roots. And again that's a close up of an are bascals. So what we have here is if we just go back to this one again we have cells within the plant root and we have hyphae and are bascals of a fungus that lives outside the endosphere. So we are aware of those kind of microbes that live inside plants like in the endosphere. But there's been a lot more study in recent times of other things that live inside plants other than these well known symbiotes. And one of the things that's come to light in recent years is what's called the corn microbiome. So this is a very very specific assembly of microbes that are in the seed of a plant and all the different species of plants will have a different assembly of a corn microbiome. So we will have a different assembly to barley, to triticali, to rye, to oats or to sunflowers or sorghum or whatever it may be. Every kind of plant will have its own corn microbiome. When that seed germinates those microbes that are inside that seed come out into the soil and surround that seed and help it to establish. What happens if we put something on the seed? If we coat it with some kind of toxin, if we put fungicide on there, if we put insecticide on there, we actually prevent that from happening. We make a difference to the corn microbiome of that plant. It's a bit like in human example we have a corn microbiome as well, which we inherit from our mothers when we're born. But if you were to take a newborn baby and dose it in antiseptic or something and fill it with antibiotics and completely eliminate all the microbes that were on and in that baby, you would have a effect on itself in the future. So we want newborn babies to inherit lots of microbes from their mothers. We want seeds that we plant in soil to have a healthy corn microbiome. So think about that. It's very, very important because those microbes form a relationship with that newly germinating plant and then they help it. They help it to grow, they enhance its nutrient acquisition, help it to get nutrients from the soil and increases its tolerance to those sobiotic stresses of things like pests and diseases and abiotic stresses of things like drought and frost. So we're actually affecting our plants fitness by if we influence that corn microbiome. And that microbial assembly that corn microbiome stays with plants for their entire life. So the microbes that are released into the soil around the germinating seed they move back into the seed again as the plant grows. They develop inside the plant and then when the plant forms seeds again the corn microbiome is there in the seed ready for the next generation. So the other thing I wanted to talk about very briefly was biological induction and that's where microbes that are in the soil move into plants. The plant will invite them to move into them and so they move from a free living soil phase into a free living phase inside the plant. They will often remain with the plant for its entire life. And again they may even end up in the seed and be distributed again when the seeds are sometimes like I mean we harvest seeds of commercial corn plants but in wild situations seeds are often distributed by birds or by small grand mammals those kinds of things this is how microbes move around in lots of cases. So why is that important? Well some of the microbes that move into plants just for example are able to fix nitrogen so they're free living in the soil. We have free living nitrogen fixing bacteria in the soil that move into the plant. Once they're actually in the plant they could be anywhere in the plant. They could be in the stems, they could be in the leaves they are able to fix nitrogen within that plant using the energy that the plant is generating from photosynthesis. Now if you do a soil test you could say there's virtually no nitrogen in this soil. There isn't enough nitrogen in this soil for this plant to grow. But if you do a leaf test you'll actually find that the plant has spot on the right amount of nitrogen in the leaves. So you'd be going so how can it have perfect amounts of nitrogen in the leaves but the soil test is showing that there's virtually no nitrogen in the soil. In fact that is how you want it to be. You want to have virtually no water soluble nitrogen in the soil. You want your soil test to show if possible zero nitrate in the soil. You want your leaf test to show absolutely optimum levels of nitrogen and that can happen. We do see examples of that happening how is that happening? That's happening because of biological induction. It's happening because free living nitrogen fixing bacteria are moving from the soil into our plants. So a soil test tells you virtually nothing. That's of any use. Apart from a soil test that tells you how much carbon you have in your soil. That's about the only useful thing a soil test can tell you. So these microbes they're significant for nitrogen fixing. They're important for plant protection. They also help the plant to fight off pests and diseases and therefore important for plant fitness. So these kinds of things are very very significant for agriculture but we've tried to replace that kind of biological activity that's been around for thousands of years with high analysis fertilisers. We think oh we can put stuff on plants to make them grow. We want to put some nitrogen on there or some phosphorus on there and get them to grow when in actual fact they already have all these mechanisms for growth. That we're interfering all the time with those natural mechanisms. So how are we going to support the microbes? Again it doesn't have to be complicated. As long as we understand that they're important we don't have to know how they talk to each other or anything else other than the fact that we have to look after them and provide conditions to have lots of them rather than using high analysis fertilisers. So we the key factors for having lots of microbes in your system are the key things that you've all been talking about for the last two days and for years in fact year long green. We want to have green for as much of the year as possible. Plant diversity is important and we use guinea as biostimulants in place of synthetic fertilisers. So just on that note of year long green we've emphasis been put on maybe letting something go through to maturity and then planting something else in it and that's fine for you know maybe a cash crop that you need to harvest. There's a lot of people now with their cover crops are looking at things like how they actually manage that cover crop because the carbon that gets into the soil is going to come from root exudates. It's very, very little carbon from above ground biomass that ever permanently remains in soil. So somewhere between root exudates count for something like five times up to 30 times more carbon in soil than above ground biomass does. So there's kind of a bit of a misunderstanding out there about well if we grow this many times of biomass it's actually going to produce this increase in soil carbon. Lots of people have been surprised when that hasn't happened. You can have plants that are only very small that are exuding massive amounts of carbon from their roots. In fact it's when they are very small that they are. So a newly germinating plant and a plant in the young vegetative stage or the early vegetative stages that is when it's exuding lots and lots of carbon. So we have Australian farmers that are trialling cover crops for the first time and trying to grow something in a very hot dry summer that might only grow six inches or maybe 12 inches or so and you know widely spaced plants and it might look like pretty ordinary. You know the neighbour especially be going what on earth are you doing. But those plants small as they are are making a huge, huge huge impact on that soil. In fact they're probably doing more for that soil than you know a six foot high crop of something that's irrigated and fertilized that is producing a huge amount of biomass and not doing anything for the soil because it doesn't need to. So the hotter and the drier it is or the more adverse the conditions are the more exudates there will be. So we see the best riser sheets and plants growing in the most hostile soils. So if the soil's got you know if it's a sandy kind of soil you'll see better riser sheets. If it's hot and dry you're going to see better riser sheets and the plants that produce good riser sheets will be the most drought tolerant. So if you wanted to select the drought tolerant cultivar or something or variety of something the easiest way to do it would actually just put them all in pots of sand, different cultivars so I mean water them for a certain amount of time turn the water off and then the ones that have the best riser sheets will actually be your most drought tolerant varieties. So we actually need to force plants. We need to make plants work. We need to force them to reduce and manage them. I probably should say we'll be a little kind. I will manage them to produce exudates. So if you let something turn from vegetating to reproductive in other words it starts to bolt up to produce flowers or seeds or initiate the production of flowers or seeds it is going to switch off exudation. So one way that you can get lots of exudates from plant roots is to at that stage graze them or mow them or do something to take them back to the vegetative stage again. So just bear that in mind. The exudates are going to be in that early vegetative state and you can get a lot of benefit from young plants that if they're frost killed or drought killed or something they'll still do a lot in the short amount of time that they're there. But we do want you long green as well and one way you can promote more green is actually to keep things in a vegetative state so they don't go through to maturity. So biostimulants what are they? Well there's hundreds of them. Different kinds of ones basically anything that supports the soil microbiome biostimulant just means stimulates biology it's not a fertilizer. And it's actually most effective when rates of high analysis fertilizers are reduced or if possible eliminated. So plant diversity also stimulates and supports the soil microbiome. There's lots and lots of research on that. The more different kinds of plants you have the more functional groups of microbes you have and the more stimulated all the processes in soil are actually stimulated through microbial processes. So again plant diversity is going to be more effective when rates of high analysis fertilizers are reduced though if you're using a cover crop for example to build soil you're going to be much better off not putting any fertilizer on that and it may not look so great but it's going to be working a lot harder make those plants work and use this bait I think you call them in this part of the world. Get out there dig holes have a look at the roots put some fertilizer on some of it and not fertilizer on the other bits and have a look for yourself. You all have to be your own research scientists and check these things out. You can't dig too many holes it's really important that you be looking at plants all of the time. So just to give a little bit of a twist and insight into some of the research there's a lot of research being done around the world now in plant diversity especially in Europe I've noticed in the UK and other places in Europe there's a huge amount of research now being undertaken into plant diversity either for multi-species pastures or for cover crops. So this experiment is in Jena in Germany. There's a river here and I'm just going to mention that a little bit later about what happened when that river flooded over these plots. These squares here are 20 metres by 20 metres which is like 20 yards by 20 yards. Some of them just have monocultures in them and some of them have up to 60 different kinds of plants in them and they've been running for 15 years. So it's a 15 year diversity experiment. And there's all kinds of information that's been collected from those plots. In this case people are looking at the insects that are around above them and someone mentioned just before me I think today, sorry I can't remember who it was but the more insects you have the more birds you don't have. So birds are often a great indicator of how well the whole ecosystem is actually functioning but they've also looked at plant biomass and they've looked at all the microbes in the soil, soil carbon, soil nitrogen, soil phosphorus. So they examined the role of the plant on a whole lot of different ecosystem processes and soil health factors. One of the things they found in this experiment was where they had in that 20 yard by 20 yard area, if they just had one kind of plant growing in there or two different kinds of plants or four different kinds of plants or eight or 16 different kinds of plants and then they had no nitrogen or 100 pounds per acre of nitrogen so they did a multifactorial experiment with all combinations of all of those factors. And what they found was that if they had eight or 16 different kinds of plants growing together it produced more biomass with no nitrogen put on it than having one or two different kinds of plants growing together with 200 pounds per acre per year of nitrogen. So what have we done in conventional AI? We have one plant kind of plant usually and we put on heaps and heaps of nitrogen and we wonder why things aren't working so well. So if we have lots of different kinds of plants they actually work better with no nitrogen because nitrogen gets in the way of this microbial communication. So high diversity produces greater plant yield that's probably more important for those of you who have livestock I guess and that's what we're seeing now is that most of the research is actually in forage systems. These experiments like Diverse Forage I think is actually the name of one of the experiments that's being undertaken by Reading University in England. So what they found in the Yerner experiment was that this is the number of plant species along the bottom from one to 16 so basically a straight line in terms of plant biomass. The more different kinds of plants you put together the higher the total biomass was and they talk about there's a little video that goes with their research they talk about you know exudates and things all the life that's happening around plant roots in the rhizosphere and also the fact that you can build much deeper soil with a greater diversity of plants. So in this diagram here there's just two different kinds of plants, a flowering plant and a grass plant and they talk about the soil depth with just two different kinds of plants together. This one they've got eight different kinds or eight functional groups of plants and you could build much deeper soil. That deeper soil turned out to be very beneficial in dry years and also in extremely wet years. I know you've just had a very wet year in this part of the world and in fact many parts of the United States have had a very wet year. Well this river here that I mentioned before the Yerner River flooded over all of those plots during this trial and the scientists thought they had lost their whole experiment. So they've gone to all the trouble to set the whole thing up and been collecting all this data and then it floods like this and they expected that when those flood waters cleared away everything would be dead and that would be the end of it. But what they found was that their high diversity plots if they had eight or more species in their plots they were all perfectly fine and even the things that died due to water logging in the lower diversity plots like some of the shorter plants that were underwater for a really long time. You could understand that some of the taller ones are obviously going to make it through but the shorter ones that died when they were just growing on their own and they were growing with the taller plants when all the water cleared away they survived. So we see this very frequently in Australia the other way around in terms of heat tolerance. We see in summertime if we have a big diversity of plants that we can put cool season plants like Ebracicas and things like that we can actually put them in with warm season plants like sunflowers and sorghum and millet and they will get through the heat of summer whereas if we just planted Ebracicas over summer they would last five minutes. They would not grow on their own but they will grow in a mix and there's lots of reasons for that for those that are just physical. Shading effects and those sorts of things but there's a lot of other things going on as well. So diverse systems are self-organising. The microbes actually know what to do and so really all we need to do is to manage for above and below ground diversity and the details will take care of themselves. Now I know sometimes in cropping situations you're not going to be able to put different kinds of plants or maybe not even four different kinds of plants together but there will be a lot more diversity in the soil if you obviously can have diverse covers before or after. A lot of you I'm not telling you anything new there. You already understand about the effects of that. Obviously diversity in crop rotations all those sorts of things but you'll also have a lot more diversity in the soil microbiome if you look very seriously at the chemicals that you're using because a lot of those chemicals are going to knock out very important microbes in the soil. So one of the things that there's been a lot of emphasis on in recent years has been soil carbon and again just to go back to this German experiment in Vienna they found that if they had 8 or 16 different kinds of plants growing together they accumulated more than 20% carbon in those soils and that's very very important for a lot of reasons because as you all know I'm sure carbon is key determinant of soil structure and water holding capacity and really helps with nutrient acquisition of plants. So if we look at that carbon molecule just to give you a bit of an idea I don't want to get too sciencey about this but there are some important things. One is that if we form humic polymers or if the microbes form humic polymers they're going to have ring structures in them which are very stable. So here we have carbon atoms joined together in a hexagon it's called an aromatic structure or a ring. So when carbon atoms join together like that it's very hard for them to be broken down by other microbes so they're going to be much more stable in the soil they're not going to be broken down easily by oxygen and they're not going to be easily decomposed by other microbes. But when we actually look at this structure of a humic molecule we then have to wonder how did all those things actually get joined together because there's carbon and oxygen and hydrogen and hydrogen in there all those different atoms which didn't just if you just put them all together in a vial and shook them up you know they're not going to magically form this extraordinary polymer. So microbes have manufactured this this is microbial process the microbes had to have a coordinated approach to making this. The humic molecule is manufactured by combination of a whole lot of different kinds of bacteria and fungi all working together to produce humus. It's really quite extraordinary. When I talked about quorum sensing and about coordinated behaviour and about some of the absolutely awesome things that microbes do in soil one of those is to produce humus. Because humus is the holy grail for soil it's got a high cation exchange capacity it's going to have it's a colloid it's going to help with water retention in the soil and soil structure and nutrient status of plants. So one of the things that's part of that molecule so about 60% of it is carbon most of that comes from root exudates. The other thing we see is that there's nitrogen in here these little blue molecules here of nitrogen. That nitrogen has to be fixed by the microbes in the soil and it's going to be fixed and incorporated into that molecule at the same time as they're fixing it. If we add nitrogen from the outside if we add inorganic nitrogen like urea or nitrate or something like that anhydrous it is going to stimulate a whole lot of different kinds of microbes in the soil that are then going to need carbon and they're going to get their carbon by basically breaking down these humic polymers and pinching the carbon from here because some of, not all of it is in the form of rings. Some of it is what we call aliphatic carbon like these blue ones that are just in chains like that that microbes can easily break off. They're going to take that carbon use it to build their bodies and actually break down our stable carbon in the soil. So just be very well aware of that. The nitrogen has to be fixed biologically in order for the carbon to be sequestered in a stable form so we really want to encourage biological free living nitrogen fixing bacteria in our soil to fix biological nitrogen and the other thing is that there are phosphorus solubilising bacteria in soil plants can't grow without nitrogen, plants can't grow without phosphorus so of course they have mechanisms for communicating with microbes to get all of the nitrogen they need they have mechanisms for communicating with microbes to get the phosphorus they need again a soil test for phosphorus is basically a waste of time because it's going to show at the most 3% of the phosphorus that you have in your soil somewhere between 1 and 3% of the phosphorus that's in your soil will show up on a soil test so you have something like 32, 100 times more than what actually shows up on a test. But the microbes can obtain phosphorus solubilising microbes can obtain the phosphorus that your plants need. They of course need energy to do that, that energy is going to come from root exudates and also those microbes that are stimulated in that process to solubilise phosphorus are going to feedback sent messages to nitrogen fixing bacteria and increase nitrogen fixing which in turn is going to increase the rate at which stable carbon is formed in the soil because unless you have nitrogen fixing happening you won't get hemispheniform. So all these things are connected again the details probably you don't need to know but it is important to know that when you add anything like water soluble phosphorus or water soluble nitrogen to soil you actually interfere with those natural processes that take place So soil organic carbon is the one single measurable factor that actually tells us most about soil health. We can tell where the things are going in a positive direction or in a negative direction by looking at is carbon increasing or is carbon decreasing. It's one thing that will really tell you a lot. Derrick shows a fantastic photo yesterday I really love that photo Derrick of your farm how it is now compared to some new land that you've just acquired and how there's been such a big change in soil colour. So we all connect with that. When we see that soil has become darker we understand it's also got better structure and better water holding capacity and that plants are going to grow better in it. We kind of know green is good for plants and we know dark is good for soil. We know that that is the one thing that can tell us the most about what's happening in our soils. But the sad news is that the organic carbon content of soil has declined around 50 to 80% in most agricultural land around the world and 30% of cropland has been abandoned even in the last 40 years. This is like well after the dust bowl has been abandoned due to soil decline which is loss of carbon and it continues to be abandoned at the rate of 25 million acres a year. So we have these massive soil degradation going on around the world and you have to wonder why is that happening? Why is that going on with all the knowledge that we have about soils these days? And the statistics actually show that 50% of the world's cropland is bare in any 12 month period. Of all the land that's cropped in the world, 50% of it is bare at any one particular time. So it may be bare because we cultivated it and in many places we went to No Till. This is an Australian photograph. We went No Till in Australia starting back in the 70s and we have not seen any improvement in soil carbon in our No Till fields compared to our cultivated fields and that was the reason was that No Till was never ever leaked in Australia it is now, but it was never leaked to cover crops or having anything green. So where's the photosynthesis? Yes we're not disturbing the soil but we're not building soil either. So we have the ESIRO which is our national research organisation over something like 20 or 30 years of research has not seen any improvement in fact these soils are still losing carbon. So disturbance wasn't the issue the issue was green, lack of green. And bare ground influences local, regional and global climate. If we had soils that looked like this in our hot summers or even schools that looked like that again we haven't made any improvement we still have bare ground that is going to radiate an incredible amount of heat. And if we look at that diagrammatically I love this diagram that came out of the food and agriculture organisation a couple of years ago but over here we have an original ecosystem as Europeans found Australia 200 years ago or the United States a little bit longer ago than that but green ground cover, other green plants and healthy soil underneath that green cover. And then we lose this is MPP decrease, MPP is just net primary production in other words you've lost ground cover for whatever reason did we overgraze it, did we burn it, did we cultivate it, did we spray it we've got all these ways that we can destroy ground cover and we've been really good at it haven't we over the last couple of hundred years of reducing ground cover and we're going to get soil degradation if we lose ground cover you all know that and then we're going to get soil again in carbon decrease you can't have less green and not worse carbon. And then when we lose carbon we lose moisture because that's what gives us our moisture holding capacity and all this extra moisture is evaporating and going up into the atmosphere and it's increasing the temperature hugely increases to my mind anyway is the chief cause of the climatic instability that we have at the moment because what happens is that when you heat something it evaporates right you take a saucepan of water and put on the stove and heat it up it evaporates so these soils get a lot hotter than these covered soils and we now have huge amounts of water vapor up in the atmosphere that weren't there a couple of hundred years ago and we have to look at that whole system in the same way we have to look at the hollow biome when we're looking at plants and microbes and the soil we have to look at plants, soils, microbiology, hydrology, global climate none of those things can be considered in isolation they're all connected and so if we look what has changed since the industrial revolution we have all this talk about climate change since the industrial revolution well what has really changed since the industrial revolution we've simplified the landscape hugely we've gone from prairies for example and had 500 to 700 different kinds of ground cover plants and some places where there was not just ground cover but there was also trees and shrubs there were 2,000 different kinds of plants you have branches here in the United States that have 2,000 different kinds of plants on them and we go to one single thing like corn or beans or whatever it may be or wheat we've hugely simplified the landscape we've reduced the amount of green you're all aware of that we've reduced the diversity of plants we've reduced the diversity in the soil microbiome and you think that doesn't have an effect on the climate it's massive because soil structure is deteriorated we want our soils to look like this to have lots and lots of fungal hyphae and nice big spaces between the aggregates where water can penetrate and air can penetrate and the reason we want to have air in there as well as water is because air is 78% nitrogen and our free living nitrogen fixing bacteria need to have that air for their nitrogen but we've gone from soils that should look like that to soils that look like concrete and you're all aware of that so if we look at that graphically here's our concrete over here where we have all the soil particles push down together no air spaces and no water between them really basically this lovely well aggregated soil over here so with this big change in soil structure it has implications well until we beyond the farm farm gate well until we beyond the farm fence actually has implications for global climate because poor structure leads to poor infiltration you're all very well aware of that we also have higher levels of evaporation and we have lower levels of soil moisture obviously all of those things are linked and I love the rainfall simulators that you have here in the United States so Ricky was saying yesterday but actually developed these or he just has his own version of this he manufactures them so he wasn't the original design of them anyway these are fantastic things we now have some in Australia thanks to Bud Davis I'm sure all of you in this room have seen a rainfall simulator it's just like such an eye-opening way of showing you know green ground cover we have no runoff here and clean runoff clear infiltration sorry underneath it so we're not losing anything from the environment we've got great infiltration right through to our heavily cultivated bare soils which have got no infiltration because of runoff with sediment and nutrients and everything and I mean it has been mentioned over the last two days and you don't have to be it's not rocket science to realise that when we're in this situation over here we're going to have a lot more floods I mean really it's not so bare ground contributes to local and regional flooding and you know the United States is not the only country to experience that it also creates a heat dome effect and I'm sure you're aware and I know that at many of the conferences people talk about this Jonathan Cobb just provided some data to me when I was here in summer time this year on their farm in Rogers in Texas the ambient temperature was 105 the soil surface in a bare field was 155 and then under a multi-species cover was 77 so if we have bare ground and lots of bare ground and remember the statistics show that 50% of the land around the world is bare at any particular time it's going to increase global temperatures isn't it if you have all the hot air so if you have air that's if the ambient temperatures let's just say the ambient temperature is 100 it's going to happen in many parts of the southern parts of the United States in summer so we have bare soil and it heats up to let's just say 120 and it rises because heat rises and then other air that's 100 degrees is going to come in hit that bare ground heat up to 120 and rise and then more air that's 100 degrees is going to come in hit that bare ground heat up to 120 and rise I mean you're actually heating up you're heating up the air making it hotter creating a heat dome when you have bare soil it has it has to have a massive effect on your local climate and the evidence is now showing it also affects regional and global climate because there is so much air ground on agricultural soils around the world so bare ground results in increased evaporation this is an Australian photo we've got covered ground on the left bare ground on the right we've got water sitting there because it can't infiltrate and so they're going to run off and cause a flood or a flat ground like a lot of our country in Australia is like dead flat it's going to evaporate it's just going to sit there and evaporate and we now know that water vapor is actually the greenhouse gas that has increased to the greatest extent since the industrial revolution in fact water vapor accounts for 95% of the greenhouse effect and there's lots of science around that so this is water vapor here these are the greenhouse gases we've got carbon dioxide and methane I think you call it methane whoops what happened there sorry just jumped through about 10 slides water vapor carbon dioxide methane nitrous oxide and then other miscellaneous greenhouse gases so it outshadows all of the other greenhouse gases by a massive amount and that's the science it has a far greater influence on local regional and global climate than carbon dioxide can someone tell me what percentage of the atmosphere is carbon dioxide like how much of the air that's in this room is probably a little bit higher at the moment because we're all sitting in here but normally if we were outside what percentage of the air would be carbon dioxide someone said 75% 3 1% 400 parts per million so 400 parts per million what does that work out as a percentage yeah lots of zeros right we're not quite that many .04 .04% of the atmosphere is carbon dioxide you really think that that's changing global climate really there is absolutely no science behind that at all to show like yes it is a greenhouse gas and so is nitrous oxide and so is methane and so is water vapour they all have those molecules all have the potential for what we call radiative forcing but when it's .04% of the atmosphere it contributes very very little to global climate so this is the guy this is the elephant in the room water vapour how come there's more water vapour well there's more evaporation wise there's more evaporation of course there's less infiltration wise there's less infiltration because there's lots more bare grounds and we've actually got a broken water cycle and you're going to hear a lot about this there are a lot of people already talking about the broken water cycle and that is the big thing that's having an impact on our climate why do we have a broken water cycle well because we have got a broken carbon cycle we've got a broken carbon cycle because we've got a lack of green plants so there is something that we can all do everybody can do and we need people in the cities you know the urban population and the policy makers and the people that make decisions actually to get their heads around this and figure out this is not going to be such a big deal we can change things and if we have more green plants it's going to be better for everybody it's going to be better for you on the farm because your soils are going to improve or if you've got livestock it's going to be more stuff for them to eat or if you know whatever you're doing on the farm is going to be easier because your soils are going to be easier to manage and more productive and less inputs required etc etc etc and it's going to be better for local, regional and global climate as well so by changing land management practices we can significantly improve climatic stability and we can increase resilience to climatic extremes because we know that the weather is always unpredictable and very variable and it has been for a long time we also know that the climate changes it has never ever stayed the same so we can't really expect it to continue being the same as it has been for the last several hundred years it's going to change in one direction or another but we can influence to a large extent how much that's changing and we can influence the stability of it to a large extent but we need a quorum of people to realise those connections and those interconnections if we're going to join the dots basically so in the same way that microbes communicate with each other through quorum sensing by producing these signalling molecules which are called auto-induces which then other microbes can detect and respond to what we actually need in the human population if we really want to do something about not only climate change but also the health of our food production system and the health of people is to start thinking about the real science and the real facts behind all of these things and finding those dots and then once we reach a tipping point a critical threshold whatever you want to call it or a quorum of humans that understand how these things work and hopefully we might get some sensible outcomes out of it and some real change in the climate so thank you very much for listening to me and I know that some of it was maybe a little bit heavy in terms of the biochemistry of it but we're going to have a question and answer session with Derek and Tom later after a break so there'll be lots of opportunity to discuss whatever aspects of those things that you'd like to talk about then.