Drought. Changing climate and weather patterns. Competition for precious water resources. New regulations. Increased pressure from consumers and the food supply chain around sustainability.
With all of these factors in play for growers, making optimal water decisions is more critical — but also more challenging — than ever. Technology developments, enhanced tools for using data, and entirely different approaches to dealing with abiotic conditions like water stress are giving growers options as using water more efficiently and effectively becomes a top priority for agriculture.
All of these issues are impacting growers today, says Al Klapp, Market Development Manager for Valagro.
“When I think about water issues, my mind immediately goes to California. As an industry, we've been dealing with a multi-year drought. We've been getting some rain lately, but it is still probably not enough to replenish reservoirs and groundwater needed to support agriculture and the municipal requirements of a growing population, particularly in drought years — which seems to be most years now. I think that's going to be exacerbated a little bit by the Sustainable Groundwater Management Act (SGMA) as that starts to roll out in California. We'll see that groundwater piece become more and more important,” he says. “It's pretty clear there isn't enough water, and we need to use it better.”
Pressures from the market are impacting water decisions as well.
“I think the sustainability expectations are only going to become a bigger motivation for growers. That's driven right now from consumers, and it's starting to trickle down to the packing houses and processing companies, and ultimately that's going to start to move down to the grower level. I’m already seeing that happen in wine grapes. We're at a point with sustainability that it's a regular question that we get during conversations with growers and retailers, and I expect that emphasis is only going to increase in the future,” Klapp says.
Given these pressures on the availability and cost of water resources, the knee-jerk reaction for any grower might logically be, “How do I produce a crop using less water?” But that’s the wrong question to ask, says Bruce Moeller, CEO of AquaSpy.
“I always tell people, if you want to save water, don't grow a crop. If you're growing a crop, you should have a strategy. And that strategy, like most things in life, is either quantity or quality,” says Moeller.
Those quality or quantity decisions around water are unique to every grower and include all the variables of resources, market conditions, weather, and more.
“If you've got a commodity crop and commodity prices are up, you want as much quantity as you can. Or maybe you're growing a specific specialty crop that has to have certain attributes, like a specific size, or water content, or taste that you can affect through process control, with water being the key ingredient,” Moeller says.
The key for either strategy, he says, is using water as a precise tool.
“Plants use their roots to dig down where the food is. So, the trick is, whether it's for quantity or for quality, you have to put the water as the carrier — and the nutrients that it's carrying — where the active root zone is,” Moeller says. “Whether that’s 4 inches or 8 or 24 or 48, you have to get it to the active root zone. Not the ‘once-active-and-now-decayed’ or ‘not-still-producing-for-the-plant’ zones, but where the active roots are.”
If you don’t, you're either going to suffer on yield, or you're going to suffer on quality. Quite likely both, he says.
“It's all about perfection. It’s about putting water in the time and place where the plant needs it, and not more and not less. Don't let it leach down to the ground table and waste it. Put it there where the plant needs it,” Moeller says.
Making strategic and highly precise decisions like this calls for data. But with the changes in weather patterns and the regulatory environment in recent years, a grower’s decades of hard-earned experience are becoming harder and harder to rely upon.
“It’s changing,” says Ben Smith, Irrigation Specialist for Semios. “A lot of the resources we use in irrigation management are dependent upon a historic record. For example, we use a 30-year record of ET to plan our irrigations, and we can't rely on those anymore because the climate is shifting. Irrigation systems have changed because the regulations change. There's a lot of pressure from all directions. So, we need to be able to have models and data and insights that are more recent and up to date to make our decisions and to base the irrigation on. It’s a big shift. We can't rely on those old practices and the old databases that we used to.”
Changing conditions are one challenge. Having systems in place to help growers interpret data and make decisions easily is another.
“The access to data has really increased in recent years, but the data that we received wasn’t impactful enough because it wasn't frequent enough, or it wasn't it wasn't a full picture of what was going on,” Smith says.
Moisture graphs are a good example. “We have had those for a long time now, and they provide a stream of data and some knowledge, but it's hard to extract. You really have to watch the trends to be able to do much with it. Growers could think of the 20 other things that needed to be out doing in the field instead of sitting in a computer and analyzing data that didn't seem to be very impactful,” he says.
With the advent of sensors that are out in the field providing real-time data readings on a broader set of variables, a whole world of information is opened up for the grower to help make choices that will be the most impactful for the current needs of the crop.
“Instead of looking at decision making in terms of periods of weeks or months, we're looking at it in 10-minute intervals. And not only data from one source or simply from observation, but data from multiple sensors and multiple sensor types on a on a single ranch,” Smith says. “There's a lot more data available and a lot more types of data that can help us to have a better understanding of, not just the soil, not just the plant, but the whole continuum from the soil, to the plant, to the atmosphere. We have access to information. So now with this data, it's a matter of taking that and transforming it into something really actionable, something where you don't have to sift through all the streams of data and try and compare it. That's one of the greatest potentials we have moving forward.”
Other new developments in soil sensors may be able to help growers make sustainability decisions with water and fertilizer applications.
“This year [AquaSpy] has a technology that isolates the ions in the soil. We have a nitrate, or NO3, sensor that has gone through several months of alpha testing in the lab and some handheld field trials and it's working to a 25 ppm measure, Moeller says. “That's kind of been a Holy Grail for the industry to find a nitrate sensor that works.”
Assuming the nitrate sensor performs in field trials, he believes the technology will lend itself to sensing other ions, including potassium, phosphate, or others material to a particular crop.
“If we can do that it becomes the same paradigm of just making root demand match soil supply. Put it where the plant roots want it. That maximizes yield and minimizes waste,” Moeller says.
Advances in water management technology go beyond traditional irrigation equipment and software, however. Tools like biostimulants that help plants manage abiotic stressors—like drought—are increasingly a part of the water management and crop quality discussion.
“A biostimulant does one or more of three things: it improves nutrient use efficiency, improves crop quality, or mitigates abiotic stress,” Klapp says. “Thinking about that abiotic stress piece, we know the average yield for most crops is anywhere from 15% to 20% short of the record yield of that crop. The majority of that yield loss is not attributed to pests like weeds, disease, insects, etc. — we can manage those challenges fairly effectively with crop protection products. So, what that means for growers is the majority of opportunity to maximize yield is by solving issues related to abiotic stress. And biostimulants can certainly be an important tool to help crops produce while under stress.”
Klapp says some of Valagro’s current research is looking beyond using biostimulants simply for mitigating water stress and focusing on increasing water use efficiency. Studies are looking at pounds of crop produced as a function of the gallons of water the crop receives. Initial field results are showing promise in the ability to increase yield while keeping water application volume the same, or preserving yield levels with decreasing water volume applied, he says.
“In either case we're increasing water use efficiency. That's a pretty exciting concept. And we're working with university researchers to better understand how to incorporate biostimulant technologies into deficit irrigation strategies,” he says.
“The reality is that's going to become more of a necessity in the future. It’s a big part of this conversation around water. Integrating biostimulants, crop water stress monitoring technology, things like stem and leaf water potential measurements, and efficient irrigation technology are really going to let us accomplish a lot in the future,” Klapp says.
So, what steps should growers of any size, big or small, be considering to make the best use of their water resources in the coming seasons? Smith suggests looking at it from two angles.
“One is the automation of our irrigation systems. The other is utilization of the data that we've been talking about. You need to get involved with both to make full use of the potential of each,” he says.
“If you're just going to do 24-hour irrigation sets, there's not a lot of sense investing in automation. But if you want to get precise control of it, you want to have a system you can automate and allow the data and the models that come from the data to feed you information, and give you insight into how to best use that automation system. They're really going to be working hand-in-hand with each other.”
Klapp points out that while most discussions on water today center around irrigation technology — things like monitoring soil moisture levels, and optimizing irrigation efficiency or uniformity — the future is going to be looking a lot more closely, not at water in the soil, but water inside the plant itself.
“There's more and more great technology out there to measure water content and water stress response inside the plant, and that's a great indicator of when and how to apply irrigation. In fact, it's probably a better method than just looking at soil moisture meters,” he says.
Biostimulant technologies can be part of the equation to increase water use efficiency as well, he says. “We can improve the uptake of water, the ability of plant cells to hold that water and ultimately produce a crop and that's the new frontier of water management — manipulating plant physiology to use a limited supply of water as efficiently as possible. I think, as an industry, once we integrate some of these irrigation technology tools with the management practices to manage water with the biostimulant piece and the plant physiology piece, we'll be in a really good position to help growers meet the challenges that we face with water use.”
At the end of the day, with all these technologies and strategies available, growers should be reviewing their options because standing pat is no longer an alternative, Moeller says.
“I lived in the Phoenix area for about 20 years, and then moved to San Diego, before I came here to Carmel, IN. When you live out West, you're innately attuned to the precious resource that is water. Back here in the Midwest, that's now starting to come to people's awareness as well,” Moeller says. “Water is not free. You're either paying to pump it, or you're on allocation, or it may be restricted by your local water district, but people are having to think through their strategies ahead of time before they plant their crop. It's as with any scarce resource. People take it more seriously because they have to, and they find ingenious ways to be more specific. When I lived in Arizona, I had a house right across from a farmer’s field and he would flood the fields. He's probably not doing that anymore. It’s adapt or die.”
