The Next Frontier
By Carol Miller, Editor, American Vegetable Grower
Arizona’s CEO of the Department of Agriculture, Paul Brierley, talks about why soil health is grabbing everyone’s attention.
Why is there so much interest in soil health? Because it promises a lot more than just a fertile growing media, says Paul Brierley, who heads up Arizona’s Department of Agriculture.
Brierley has spent his career in agriculture, including a 10-year stint with the Arizona Farm Bureau as Director of Organization, and as the founding Executive Director of the University of Arizona’s private-public research group Yuma Center of Excellence for Desert Agriculture (YCEDA).
I sat down with Brierley to ask him his views on why soil health has been getting a lot of attention in his part of the world.
Carol Miller: What are some of the soil-health challenges in the Southwest?
Paul Brierley: Most of the soil-health research and soil-health products are really from the Midwest. They bring them out here and say, “Hey, you ought to use this.”
But we've got a lot of different soils from the Midwest out here. A lot of different climate conditions. It's hot, hot, hot soil, and the [beneficial] bugs don’t always survive.
So there's a lot of research, some of it through the Yuma Center of Excellence for Desert Agriculture [YCEDA]. They have a new thing called the DASHI. It's the Desert Agriculture Soil Health Initiative, and they're working with University of Arizona soil-health researcher Dr. Joey Blankinship.
They're trying to put measures around what “soil health” even means. People talk about soil health, but is it something you can measure? What are you looking for? I mean, there's soil organic matter, soil structure, nutrient content, pH levels, biological activity, and water retention, to name a few. There are lots of different attributes to it and different thresholds.
So, they're trying to quantify what is healthy soil. And once you do that, then you can measure the impact that different practices have, or different products.
CEO & EDD, Arizona Department of Agriculture
Then there are some companies that I'm aware of here in Arizona doing good work. One, MyLand, has the ultimate aim to ramp up native algae in the soil. They take soil samples from your farm, take them to their lab, and grow different forms of algae that are in [the samples]. They select the ones that have the best attributes for their system, and intensely grow this algae that was native to your farm.
And then they feed it into the irrigation system. Now you're super charging the soil with native algae that should be able to survive because it's native. And that helps with nutrient availability. It helps increase soil organic matter, so you have more water holding capacity. They're seeing really good results with that.
Another is a liquid natural clay. A Norwegian company [Desert Control, desertcontrol.com] has found a way to turn clay into a liquid product that they apply to the soil. You can put that on pure sand, and it becomes more like healthy soil with water retention capabilities.
Then there's work on biochar and things like that. So there are a lot of efforts.
The biggest takeaway is, in the desert climate, the products that are claiming to provide soil health don't necessarily do that. So there's just a lot of research going into how do you quantify what is soil health and how do you get there in the desert climate?
Miller: A couple of years ago, a researcher told me that soil is kind of the final frontier when it comes to agriculture. Why would that be?
Brierley: Well, I personally wouldn't say final frontier, because we don't know what else is going to come along. But I think it's the next frontier.
Some of the early research we looked at at YCEDA was trying to non-destructively monitor root growth and the root structure, because what's going on under the ground is every bit as important as what's going on above the ground. Not to get philosophical, exactly, but you don't see it, right? You see the plant above ground. But it turns out what's going on below ground is just as important. And then there's really not many good ways to track it without destroying, without picking the plant and looking at it.
We actually took some plants through an MRI machine, hoping that we could finetune the MRI machine and see what was going on with the roots. I just think it's really hard to study. We don't see it. We just sort of take it for granted. Many of the diseases are in the roots.
But it turns out a lot of diseases that vegetable crops face, like fusarium wilt of lettuce, root rot, verticillium wilt, and nematodes, when you pull the plant out and cut into the roots, you can see what's happening. It's filling up with the disease. That's blocking the water flow and that's why we get the wilt.
There's not really been a good way to non-intrusively monitor that. So, it's both out of sight, out of mind, and difficult to really figure out what's going on until it’s too late.
If you think about it, the plant's putting just as much effort into what it's doing in the roots as to what it's doing above ground. So that's the reason I think it's the next frontier.
Maybe the other reason is we’ve grown crop after crop after crop. You start using all the nutrients that are in the topsoil, and now you need to worry more about how you treat it so that you don't wear it out. A lot of new science needs to be done in that area.
The other thing is, we have to understand the extent that it will help with water conservation. We have a lot more pressure now on using less water.
Miller: How would soil health impact water conservation?
Brierley: Healthy soils, soils of higher organic matter, are going to retain water better. I think you might have seen in some of our previous studies that soil salinity is a big problem. You have to add more water than what the plant needs to leach the salinity.
The hope is that some of these soil health efforts might be a way to reduce the salinity, or at least the impacts of the salinity on the plants, so you don't have to use as much water to leach the salts away.
It's kind of seen as almost the next frontier of how we save water. Not to mention that higher productivity with the same amount of water is equivalent to water savings.
But then, of course, you have other things like mitigating plant disease and increasing yield and nutrient availability.
I've learned from my early days in Yuma that there's tons of phosphorus, but it's locked up in the soil, and it's not in an available form. And some of these soil amendments like algae and maybe biochar would actually make that phosphorus available to the plant and not have to apply as much of the chemical fertilizer.
There's a lot of hope around soil health and what it might do for the growing industry.
One thing I've mentioned is how desert soils and desert cropping patterns are unique and need to be addressed. But if you believe that as a planet we're getting hotter and drier, these desert regions are kind of the canary in the coal mine, right?
If we can figure out the ways that soil health can help us stay productive in the desert environment, that can help other regions that get drier and get hotter, even if they don't face the same problems right now.
So, I think it's a worthwhile investment to figure out how to do soil health right in the desert, because it can impact a lot of the world.
Miller: Arizona passed some legislation on soil health this past year. What did it cover?
Brierley: The legislation that you're referring to empowered the NRCDs (Natural Resource Conservation Districts) to create a soil health program under the natural resource conservation districts.
Continue reading on page 5 →
That was passed and empowered them to, “create and administer a soil health program that promotes implementation of soil, health practices, research projects, demonstration projects, educational projects or other activities appropriate to promote the continuing capacity for soil to function as a vital living biological system that sustains plants, animals and humans. Increased soil organic matter improves soil structure, water holding and nutrient holding capacity, or nutrient cycling.”
So that's what was passed. But it didn't come with funding. It authorized them to create those programs.
There's an Arizona Association of Conservation Districts, and they received $5 million from the USDA's climate smart grant program. So, they are administering that grant going towards a soil health effort from that climate-smart grant program that USDA provided.
What Is Causing Water Shortages in Arizona?
Paul Brierley: It really is both. There's less water. Thinking of the Colorado River system, you know. It's allocated 16.5 million acre-feet (when you count Mexico).And In the last 20 years or so, it's producing like 12 million acre-feet.
Long term you’ve got 1.4-million-acre-foot deficit every year. And more recently, it's more like a 3-million-acre-foot deficit. We definitely are seeing less. Not just less precipitation.
But the other thing that's happening, there have been years when they get nearly a normal snowpack, so nearly normal precipitation. Say they get 85% to 90% of normal. But then the flow into the reservoirs, the storage reservoirs when it melts, has been like 35% of normal.
What we're finding is with maybe the spring turning warmer, faster than it used to, the snow sublimates or the soil so dry that it soaks it up. But even almost normal precipitation doesn't mean you're going to get normal runoff into your reservoir systems. And that's been a surprise and an unexpected thing. So we've had a lot of dry years.
Continue reading on page 7 →
And then, like, I say, even the even the more normal years aren't giving normal runoff. And so we've had these big lake systems to store the runoff and then be able to meter that out. And they're just. They're down at 2530 of capacity and yes, you have more users also. So you know.
The full allocation wasn't being used before there was there was extra water, and and that's not the case. Now everything is being used, and there's more demand.
Paul Brierley: I don't like to be cynical, but so much in agriculture — and everything in life — comes down to economics, right? And so it's got to pencil out.
When I was at the YCEDA, it was really about productivity, mitigating disease, things like that. Now it's more about water savings.
I think that's kind of the existential threat to agriculture in Arizona. How do we keep producing even with less water? And so the focus shifts a little bit. But either way, whatever your reason for wanting to do it, is it? It's got a pencil out. And it turns out it's kind of difficult.
One of the things that really stuck with me when I was in Yuma, and getting some of the growers to collaborate that we were looking for matching kind of in kind support for a grant. That we were applying for. And one grower told me something really stuck with me, he said, and you're aware of how the arrangement is with shipper companies contracting with growers to grow their products.
And the grower said, We've tried a lot of the soil health stuff, and we believe in it, he said. We know that, you know, three to five years down the road, we're going to get payback on what it on what we've expended on it. But, he said, the problem is, we can't get the shippers and I don't mean to throw them under the bus. But you know he’s got to do contracts with the shippers every year, and they have a pretty sharp pencil, you know. They know what it takes to produce. And they've got a lot of choices of different farmers and so, he said, we have trouble getting the extra $5 or $10 an acre that we need to do some of these soil health practices because we can't. We can't get it into our contracts for growing. And the other factor is a lot of the growers don't own the land they're on, they're leasing the land. And so if your benefits come 3 to 5 years down the road, and you might not even have that lease anymore.
It makes it hard to expend the money that you need to get there. So I think there's a lot of research still that needs to be done just to quantify and show what different things do. But once you do that, you have to figure out the economics of it. And how do you make that work?
You know that could be through water savings or enhanced productivity, or whatever. But you’ve got to figure that out.
