Converting Data to Action and Efficiency
By Thomas Skernivitz, Senior Editor, American Fruit Grower
While essential to the process, data derived from a remote-sensing technology such as T-REX (see Irrigation Data: Remote Sensing for Optimum Efficiency in this report) is not the end-all for almond growers intent on optimizing their irrigation programs.
Enter automation. According to Tom Devol, the Irrigation and Technology Advisor with the Almond Board of California, automation is the “next big jump we can make in water use.”
“We’re pulling in data. We’ve solved this ‘when’ and ‘how long.’ When you think of this data … we feel we’re good, right? But we're not making those fine adjustments to our irrigations,” Devol said at The 2023 Almond Conference. “We're not capturing that savings of 15 minutes next week that we could pull back. Or there's a heat spell coming in; we need to really bump it up. We're not following the resolution of what ET is or ETc or ETa. Our limiter is really automation. Automation is the tool that allows us to let the system do it. It lets you deal with these small fluctuations throughout the year. It's not just water. It's nutrient savings. It's energy savings.”
Devol moderated a panel discussion on automation at The Almond Conference in Sacramento, CA, in December 2023. Participants included: James Nichols, President, HotSpot AG, Hanford, CA; Jacob Christfort, President, Ranch Systems, Novato, CA; and Guillermo Valenzuela, Vice President of Sales and Marketing, WiseConn, Redondo Beach, CA.
Devol: What is holding back your customers from automating?
Nichols: “I think economics is one thing that holds growers back from adopting more automation. There can be some high upfront costs.”
Christfort: “A lot of growers have had bad experiences. I don't think any of the vendors here are to blame, but there's a lot of other vendors that are not here at the table who have been out there with technology that might not have been ready. That has given some growers a very bad experience. It's hard to come back in afterward, no matter how good we are, when the grower has been burned.”
Valenzuela: “If I had to choose one, it would probably be the training that growers invest in for their irrigation people. There's this misconception of this being rocket science, which it’s not. We've worked hard on making it simple — as simple as we can — so that anybody can actually run it … where before it was very complicated. The actual irrigation workforce was not ready for it. That has changed now.”
Devol: On the flip side, what benefits are they seeing?
Valenzuela: “You’ve got labor savings if you're not paying extra labor for the irrigators. The irrigators are not actually opening and closing valves anymore. They're still walking the fields, they're flushing the lines, they're unclogging the emitters, but they're not responsible for opening and closing a valve. At a hundred bucks a day for an irrigator, that's actually an expensive controller. Then you’ve got the truck he's driving. It’s burning gas, and sometimes there's human error, which is hard to quantify. If he's got to run an errand at home, he'll just leave the pump running until tomorrow. Maybe he flushed the fertilizers. There's a whole lot of things that happen when you're running manually."
Christfort: “I talk to a lot of owners of operations who are not necessarily close to the operation themselves but are very concerned about how it gets irrigated. Say a winemaker that's not actually part of the vineyard team, automation enables them to know what actually gets irrigated. I've talked to many winemakers who have said, ‘I've told them how much to irrigate, but I know it's not what's being irrigated manually. But when it's automated, I know.’”
Nichols: “Some of the longer-term benefits of automation are tree health and productivity. When we first started trialing the automation on our own farm, we had some troubles with disease and nutrition management. We implemented an ET schedule combined with automation. The first year we didn't see the yield improvements, but we saw much better leaf nutrient analysis. We didn't have to spray for mites as a result of higher K levels. And then the second and third year after that we really started seeing the yield improvements. So short-term cost savings and then longer-term revenue benefits.”
Devol: Pulse irrigation is really hard to do manually. If you're doing three- or four-hour pushes, that's a lot of activation of valves. Can you speak to that?
Valenzuela: “It’s impossible. (One grower) had 60 valves on a 150-acre ranch, and he wanted to open them 10 times a day, each one. His brother did it for a few days, then he quit. We've seen a tendency toward high-frequency irrigation — or pulse irrigation, people call it — because there's several benefits in terms of water consumption. You're putting water to certain depths as you're not going below 18 inches in almonds, which is what we've seen. You’re basically irrigating the trees like they were in a pot. It has its pros and cons. You don't have reserve water underneath, so if you have a problem with your irrigation system, you only have a couple of days before you're fully stressed. But we've seen this tendency because it helps you irrigate across the board all your different soil types. When you do high frequency, you don't have any soil type that's suffering, so now you're irrigating every day, twice a day, three times a day. … But without automation, it would be impossible.”
Devol: Is automation complex to manage?
Christfort: “This is definitely not a first-time-irrigating farmer that would get into this kind of thing, but for the more advanced users or irrigators, or maybe in some cases our resellers that step in, we have a little formula or scripting language that you could compare with Excel spreadsheet kind of skill level, where you can create relationships between things like ET, things you might have sensed on the sensing side of your system, and then feed that into your irrigation schedules. You could build, if you really wanted to go crazy, an individual irrigation system based on formula, but for most people, they’ve got a baseline, and they just throttle that volume button up or down.”
Devol: Are you recommending growers put valves at the pump station or in the field?
Valenzuela: “We’ve got people that start off very simple, just in starting and stopping the pump, and all they have in the field is butterfly valves, so they don’t make many changes there; all the way down to spoon feeding the fertilizer in a proportional way to make sure that I'm injecting fertilizer every time I irrigate. We've got guys that are irrigating by variety, so we’ve got a valve for the Nonpareils, and we got valves for the Montereys, the Sonoras. We are basically cycling through the valves to maintain pressurized systems, so we have a better distribution uniformity. Soil-specific irrigation, pulse irrigation — there's all sorts of things that you can work with and get very complex to the point where you're separating the valves per soil type, or as simple as a timer like the one in your lawn. The systems have been built for you to start very simple and for you to go all the way as deep as you want.”
Devol: In-field valves: wired or wireless or both?
Nichols: “Starting out with wired, the advantage is if it's done properly, if it's put in conduit or very heavy rubber, it's down deep, next to say a mainline, it could be a very reliable control solution for in-field valves. One of the downsides is that you generally can't get feedback as far as how the valve is performing. If you want to know pressure, you have to run quite a few more wires just to get that. It can be a very valuable solution prior to an installation going in. To run wire after the fact is probably cost prohibitive. As far as a disadvantage, if you’re running a chisel and clip a wire, you could be taking down your entire system, and it could be a while to try and figure out where to fix that wire. The advantages for wireless or cellular: They run on their own solar battery, so if the tractor hits one of those, only one station is going down. Cutting a main wire can take down the whole system."
Christfort: “If you have wires and they're in good condition, I think you should absolutely use them. They're a good thing to have. I think it's more of a consideration, ‘If I don't have them, do I want to spend the money putting them in vs. just go with wireless. Wireless will probably be cheaper because you probably want feedback sensors at various places anyway. You could argue that wireless control itself is almost free for the valve. It's going to be a big cost difference if you don't have the wires already.”
Valenzuela: “’WiseConn’ comes from ‘wireless sensors connections’ actually, so we like wireless. Having said that, we end up using a hybrid. If the wire's there, and then one valve stops working because the wire got stolen or whatever, you just put out one antenna, and you put that valve on wireless, and the rest stay on the wire as long as the wire works. But even on new designs, we've been working with companies, so when you're doing a new development, you cluster the valves together. Your automation and your control system is cheaper because you're putting up to five, six valves on one controller. Even if you have to run 100 feet of wire, you're not running miles of wire. You're just running very short shots of wire just to be able to control several valves on one controller. That's kind of the way we go — more of a hybrid.”
Devol: What if the valve doesn’t open? How will I know?
Christfort: “Nowadays that’s a very basic functionality of any automation system of the cloud-connected type. When you sell these systems, we always tell people you’ve got to have a feedback; something that shows whether the valve opens. At the minimum, that would be a main flow meter, but the ideal is a pressure sensor or a flow meter after each valve. But the minimum would be the main valve, and then you can at least see there's a feedback at the main water meter. Either works, so you can be fine grained in your feedback, or you can be just centralized in your feedback.”
Devol: How up to speed is the irrigation design community on control?
Christfort: “I would say that they are, in general, up to speed on irrigation design and also automation, but when you get into the wireless stuff, there's more training necessary. They're not necessarily used to designing those systems with the line of sight between antennas and all of that. When we work with a new designer or reseller, we encourage them to start out with the type of controller that is basically a plug-in replacement for the traditional irrigation timers that they are used to but takes it to the cloud because then they have something familiar to start with and learn on. Pretty quickly they will then be adding wireless sensors to that and get more sophisticated. But it's a good place to start as a sort of hands-on training."
Nichols: “We're blessed in California to have some very good irrigation schools with design emphasis that we benefit from as automation vendors. As far as designing irrigation systems for automation, if it could be done easily manually, it could be done easily with automation. One thing that may need more education is on the flow meters themselves and the position of where they are at the filter station. Having reliable feedback from the flow meter is really important to prevent accidents or blowouts from happening. We see a lot of cases where the good flow meter was picked for the wrong spot, and in some cases have a lot of trouble connecting to the flow meter just because it's not reading properly. At the filter station a lot of the new-style mag meters are not compatible with fertilizer injection. That's just one small critique, but otherwise I think the irrigation designers that we work with are doing a great job.”
Valenzuela: “I'm actually going to shout out to some of the irrigation companies that have taken on the automation task and built an automation department and taught their engineering department and the design team how to design for automation. When I moved to California back in 2015, this was not even a topic. We have to understand that this is a very small portion of the irrigation business. Most of the business is on the PVC, on the drip lines, that's where the money is. That's the projects that they're seeing. I like to tell them, ‘You're selling a TV, but you're not giving them the remote control,’ and I'm sorry, man, but without a remote control, I'm not buying a TV. Maybe back in the ’80s. You’ve got to be able to learn remote controls. It's a small portion, it's a hard portion. You need a dedicated team, it's not hydraulics, you need specific technicians that know electricity. In the last eight years I've seen some of these companies gear up, invest to add people just to be able to support their growers and add the technology component to the irrigation systems. And then there's other companies that are popping out that are providing services only around the automation and irrigation management.”
Devol: This concept of irrigation as a service: Is it picking up speed with growers?
Valenzuela: “We've seen a lot of interest in having somebody to help on not only running the automation system but also on the agronomic side. We've added weather stations, soil moisture probes, dendrometers, leaf temperature sensors. There are a bunch of sensors out there — the FloraPulse sensor, for example. How do I use all this information? A lot of these companies have come in the door, saying, ‘OK, I'm going to help you make the decision. I'm going to help you read this data, interpret it, and come up with a frequency and duration program for the week.’ And then they're gone. And then the irrigator is back to controlling the water, and he doesn't follow the instructions exactly as the recommendation said, so you're not getting the actual value of the service because you're not executing the actual recommendation that was the optimum irrigation schedule for that case. That’s when automation comes in. It closes the loop.”
Devol: Is fertigation a mature option at this point?
Nichols: “We're seeing customers embrace it. The primary benefit is for time savings and then having confidence in delivering the right amount or the prescribed amount of fertilizer at the right time.”
Valenzuela: “The timing of the injection is the key, and I think fertilizer companies and distributors and PCAs have figured out that when you inject it is key, and if you're doing it continuously, timing is key. We've run into ranches where, ‘Yeah, I injected the whole 500 gallons last night and then just left the irrigation system running.’ We’re, like, ‘OK, that fertilizer is probably like 5 feet deep by now.’ The timing is crucial. You want to put that at the end of the irrigation. You’ve got to calculate it so it stays on your root zone, so you can get the performance out of it, and then you have to have the correct pH because if you're irrigating with an 8.8 pH in the water, you might as well not inject any fertilizer.”
