Blockages in micro-irrigation systems are a drag on the return on investment for any grower. Although it is tempting to add another push-in, it does not help to cure the problem. And that’s where U.S. water company Kurita America comes in, supplying water treatment products to the domestic agricultural market, some of which are for post-harvest. Kurita America has a new product on the horizon the company says could reduce the need to apply ag-grade sulphuric acid to control soil pH. New AG International’s Luke Hutson spoke to the Kurita America team.
An analogy that Brice Jones, Kurita America’s regional manager for ag water, likes to use is: “There’s no point buying a Ferrari and not changing the oil.” By this he means there’s no point in investing millions of dollars into an irrigation system and not addressing the problems of scaling often caused by elements dissolved in the irrigation water, such as calcium, iron or manganese.
Scaling will ultimately plug the emitters in the system, reducing its efficiency. That’s where Kurita comes in. Its portfolio includes products to unclog the build-up of calcium carbonate, as well as treatments for post-harvest washing of produce.
“Growers are still getting used to the idea of treating water,” says Jones.
The Kurita America products are mostly liquid formulations applied at the point of filtration. The products are introduced to the system when the irrigation is turned on.
“Our knowledge of water is what we bring to the game,” elaborates Jones. “Our expertise is in water chemistry, knowing what chemistry to use, how much to use and when, and in what circumstances.”
The business currently focuses on California, the largest area for micro-irrigation in the U.S.
Punching holes Blockages in irrigation emitters are often circumvented by “punching” a new hole in the line. Jones describes walking onto a farm and being able to assess the state of maintenance of the irrigation system by how many holes have been punched into the irrigation pipe. This is when growers literally create a hole in the plastic pipe or add what is called a push-in.
Brice Jones, Regional Manager for ag water, Kurita America
A common sign of sub-optimal irrigation caused by blockages on a tree crop is when there is a row of uniformly smaller trees, adds Jones.
Distribution problem Bryan Hansen is an area manager for Kurita America. He can scan a field and spot areas where they might be a distribution problem.
“We see this with field-grown tomatoes,” says Hansen. “Normally the distribution is poor towards the end of the field.” And again, there tends to be a noticeable difference in the size of the crop.
Kurita America also does onsite analysis to check pH and to see if there are any unwanted biologicals. When it comes to unwanted biologicals, knowing the water source is important. “We can tell if [it] comes into the system or whether it grows in the system, and we then formulate a program.”
One example is iron-reducing bacteria, which are small organisms that occur naturally either in soil or water, such as groundwater or surface waters. The bacteria combine iron with oxygen (or manganese with oxygen) to form deposits and a slime that sticks to irrigation pipes.
Combating contamination Post-harvest processing is another major segment for Kurita. Before dispatch to the supermarkets, fruit and vegetables are subject to a
There’s no point buying a Ferrari and not changing the oil.
Bryan Hansen, Area Manager, Kurita America
spray bath where it is important not to introduce any bacteria that could cause human illness when consumed. Jones says in California there are occasional E.coli outbreaks traced back to the production of lettuce and the grower’s water source. One of the main lettuce growing regions in California is Gilroy. Food safety presentations in this area always draw a large crowd, Jones notes.
New product Kurita is working on an alternative to sulphuric acid which is used extensively in agriculture to lower soil pH and improve nutrient uptake and availability. Although the sulphuric acid does lower the soil pH, it does have disadvantages.
“Over time, the produced salts of the acids and decreased porosity of the soil creates issues with water
penetration and nutrient uptake,” explains Jones.
Typically, agricultural-grade sulphuric acid is used in volumes of 10 or 20 gallons at a time, while the Kurita product will be applied in parts per million.
“We are excited about this new product and a study we are working on that will replace sulphuric acid, releasing previously unavailable nutrients in the soil while improving water absorption and, hence, long-term soil improvement with increased crop production.” ●
Blockages in irrigation emitters are often circumvented by ‘punching’ a new hole in the line.
Natasha Rankin, MBA, CAE, is the U.S.-based Irrigation Association (IA) new chief executive officer, assuming her role on Jan. 10, 2022. Rankin took over the CEO role from Deborah Hamlin who retired.
Rankin brings more than 25 years of experience to the IA, including nine years in chief executive roles. Most recently, she served as the chief strategy officer/chief operating officer for the American Counseling Association, where she helped the organization achieve record levels of membership and revenue growth. Previously, while at Bostrom Corporation, Rankin held the position of executive director for the Employers Council on Flexible Compensation and the Greeting Card Association. During her career, she also served as executive director of the General Federation of Women’s Clubs.
In addition to executive roles, Rankin has extensive experience working with associations, including meeting planning, advocacy work, professional development and implementing membership growth strategies. She has also been involved with the American Society of Association Executives, currently serving on the ASAE Foundation Innovation Task Force and on the ASAE Political Action Committee, where she is recognized as an APAC Ambassador.
Natasha Rankin, Irrigation Association CEO
Rankin spoke with NAI editor Janet Kanters on her new role with the IA.
Q. Welcome to your new role as CEO of the Irrigation Association (IA). What attracted you to the association? A. The mission and work of the Irrigation Association is one that strongly resonates with me. I grew up in the Willamette Valley in Oregon (U.S.), which is one of the most fertile areas in the Pacific Northwest. My extended family and friends throughout Oregon were involved in farming and ranching, and I saw their deep commitment to the land, their crops, their livestock and our most precious resource, water. Wise water management and our climate — and its impact on our businesses, communities and each of us individually — were topics of conversation around the family table from my earliest age. I also happen to live on a homestead in Virginia, located in the heart of wine country in this state. Water management and sustainability are keys to me, my neighbours and my community’s continued growth and success. I’m excited to work for an industry so essential to our society. There is a passion among our members that I would like to see spread beyond irrigation. This passion elevates our industry, increasing the level of education, technology and professional services in the marketplace.
Q. You have extensive experience working with associations, including meeting planning, advocacy work, professional development and implementing membership growth strategies. How will you transition some of these skills into your work with the IA? A. I’ve been incredibly lucky to have a varied career that’s given me a wealth of experience in strategy, public policy, program development and membership engagement, which have helped me grow revenue and profitability, influence and membership of the associations I’ve worked for. Those successes aren’t mine alone, as I have a deep appreciation for working in collaboration with my board, leading and mentoring professional staff, and engaging volunteers, members and partners in that work. I’m excited about bringing people together; tapping into their skills, knowledge and passion; and working in partnership toward the continued success of the IA and the industry.
Q. Digging a little deeper, revenue growth is important to the IA, as is member relations. How do you propose to maintain and, indeed, improve both areas? A. Members of the Irrigation Association, as well as irrigation professionals, educators, researchers and farmers/growers, have been incredibly generous in sharing their time and perspectives with me. I’m listening to and learning from them to better understand their needs, the challenges and opportunities in the marketplace, and what they are seeking from the IA. From the insights I’m gaining and the data we have, I look forward to the IA refining its activities, programs and initiatives to further help our members develop their workforce, grow their businesses, and expand awareness and influence with policymakers.
Q. Your predecessor at the IA established a new brand and mission, consolidated industry training, and developed a profitable online learning center, amongst other things. What are the main goals for yourself and your team moving forward? A. In my “listening tour” during these first months, what I’ve heard and what resonates with me is that we need to be more effective at telling the compelling story of irrigation. The Irrigation Association and its members are thought leaders. They have an incredibly positive story to tell of sustainable solutions, wise management and forward-thinking innovation that contribute to our health, safety, security and recreation.
Q. The pandemic continues to disrupt the world. How do you propose to get the IA back to “business as usual” now, and in the future? A. This is an exciting time for the Irrigation Association. Our industry, like many others, faced multiple challenges during the past two years, but through our challenges came many opportunities. People, now more than ever before, value outdoor spaces. They are also more attuned to where their food comes from and what the environmental footprint is. Water — and how we irrigate — plays a major role in this. We want to continue providing and even growing our excellent education and certification programs — in person and online — along with expanding our reach in advocacy and ensuring that we effectively communicate the benefits of efficient irrigation and its impact on our communities and the world. ●
When salty groundwater is used to irrigate almond orchards, production can be significantly reduced and the damage to trees can last for years, according to USDA Agriculture Research Service studies.
Years of droughts in central California, the primary growing region for the state's USD$6 billion almond-a-year industry, have forced producers to draw ever deeper from aquifers to replace limited higher-quality surface water to quench thirsty almond trees.
As groundwater levels have declined with pumping and drought, the quality of extracted groundwater in some areas also has declined as wells have had to reach deeper into levels with sediments of higher salinity. The higher salt content of this groundwater poses a significant threat to productivity with almond farmers reporting yield losses of more than 30 percent.
To investigate the impact that elevated salinity levels have on almond harvests under real world conditions, Agricultural Research Service (ARS) scientists at the U.S. Salinity Laboratory in Riverside, California, and the San Joaquin Valley Agricultural Sciences Center in Parlier, California studied multiple locations in three commercial almond orchards – two in the western San Joaquin Valley (SJV) and one on the eastern side of SJV.
Western SJV groundwater is three times saltier mainly because the
aquifer floor there consists of marine-origin deposits, which are naturally higher in salts. In the eastern SJV, the aquifers lie over riverine sediments from Sierra Nevada granite, so are less saline and the ground water is about 0.5 dS/m.
"It is not surprising that almond trees in the western SJV are seeing more damage from higher amounts of salinity as growers are forced to substitute ground water for surface water,” noted Ray Anderson, soil scientist with the Agricultural Water Efficiency and Salinity Research Unit in Riverside, who led the research. “However, previous models predicted a yield loss of more than 60 percent with the soil salinity we measured, so almonds have greater salt tolerance than we previously thought" Exacerbating tree damage are the efforts growers have been taking to be more efficient with all irrigation water. Conventionally, growers have flooded orchards with surface water, which washes out salt buildup in the soil. Now they are using drip irrigation, which can cut water use by up to 50 percent.
An almond orchard with drip irrigation in Madera, California, coming into bloom.
Photo: Dennise Jenkins.
But drip irrigation also concentrates irrigation water directly to the root zone of each tree. As droughts and surface water curtailment become worse, there is little or no opportunity to flood orchards and move built up salts away from the roots.
Still the most unexpected finding from their research was how lasting the impact of exposure to higher salinity groundwater was, according to Anderson.
"Even a few years of exposure to high salinity groundwater had hangover effects that persisted for multiple seasons and manifested itself in many ways, including increased tree mortality and canker,” he said. “So, while the trees had more salt tolerance than we first thought, there were more lasting effects. "Because of this hangover effect, it is better to minimize use of the high salinity groundwater."
What this work shows is that water quality may be equally as important as water quantity. They both need to be actively considered right alongside each other, Anderson explained.
"And groundwater may not be as effective of a bridge for drought years, as we have previously believed," he added. ●
Higher biomass, less water and more fruit are the results of the first year in a Texas A&M AgriLife Research study comparing mobile drip irrigation (MDI) to low-elevation sprinkler application (LESA) irrigation systems.
The project, comparing types of irrigation and irrigation scheduling, is led by Charlie Rush, Ph.D., Texas A&M AgriLife Research plant pathologist and a faculty member in the department of plant pathology and microbiology within Texas A&M University's College of Agriculture and Life Sciences, Amarillo.
Rush is working with the U.S. Department of Agriculture-Agricultural Research Service faculty at Bushland and industry partners to investigate the potential of producing high-quality vegetables under irrigation for fresh market sales.
The two-year study compares MDI and LESA irrigation systems against the traditional subsurface drip irrigation. Additionally, the study uses neutron probes to measure soil moisture and help determine irrigation timing.
The MDI system attaches to existing centre pivot irrigation systems and applies water directly to the soil surface as the driplines are dragged across the field to provide uniform wetness.
Ranjeeta Adhikari, Ph.D., a post-doctoral researcher in Rush's program, ran the trials using two spans of a traditional LESA centre pivot system, retrofitted with MDI on the AgriLife Research facilities at Bushland. The study included four replications of each MDI and LESA, with 10-foot row spacings and 26 inches between plants. Production was compared to that using traditional stationary drip as a control. While the plan was to use both tomatoes and watermelons, herbicide drift damaged the tomatoes. So, the same variety of watermelon was planted across the entire test.
The team transplanted the watermelon plants from the greenhouse on May 27, 2021. Harvests were Sept. 1, Sept. 15, Oct. 1 and Oct. 15. During the second and third harvests, they selected an equal amount of fruit for quality analysis. The LESA tests did not make it to the fourth harvest, as the plants had died back by then.
Adhikari said there was no difference in the sugar content and fruit size of the watermelons between the treatments. But there were significant differences in other areas, including higher biomass (35 percent more) and ground coverage appeared under MDI compared to LESA; vegetation difference started to show 40-45 days after transplanting; MDI led to a longer vegetative and fruit-growth period (the plants under LESA started to die earlier than those under MDI); the number of fruit and total fruit yield was much higher with MDI (almost 30 percent higher) compared to LESA; and, LESA used more water for the same amount of production.
During the first phase of the experiment, from planting to mid-July, the same amount of water was applied with LESA and MDI – one inch per week for a total of nine inches, Adhikari said. During the remainder of the growing season, neutron probe readings of each plot dictated how much water the plot would receive.
The LESA plot received 13 inches during this second phase, reaching a total of 22 inches. The MDI section required only 10.5 inches in the second phase, for a total of 19.5 inches. Yields recorded: single fruit weight averaged 13.9 pounds under LESA and 14.7 pounds under MDI; number of fruits per plant was 1.5 under LESA and 1.9 under MDI; and, fruit yield averaged 20.1 pounds per plant on LESA and 27.5 pounds per plant for MDI.
"Since the water applied was less with MDI, and the yield was higher, the overall water-use efficiency was higher under MDI," Adhikari said. "MDI allows the water to be applied directly to the root zone, while the LESA application doesn't all fall on the root zone, affecting everything from forage to fruit. More of the water evaporates and is inaccessible under LESA."
Rush said this initial year of study offers promise. The study will be repeated in 2022 to see if similar results are recorded. ●
The spray pattern on the typical centre pivot system with LESA hoses is much broader. Photo: Texas A&M AgriLife photo by Qingwu Xue
The United States Department of Agriculture is funding USD$1.2 million for the study of a high-clearance robotic irrigation system that will eventually be used in Iowa.
The project, which aligns nutrient application timing to a crop’s nutrient needs to improve efficiency and reduce nutrient loss, is a collaborative of Iowa State University (ISU), the 360 Yield Center and The Ohio State University.
Agricultural engineering specialists with ISU Extension and Outreach will lead Iowa State’s research efforts. The team includes Daniel Andersen, Kapil Arora, and Matthew Helmers, as well as Kelvin Leibold, farm management specialist with ISU Extension and Outreach.
According to Arora, the collaborative project intends to demonstrate an innovative unified strategy of in-season application of commercial or animal nutrients along with water application to reduce nutrient losses while improving profitability with increased grain yields.”
Additional researchers and industry collaborators will include Scott Shearer (lead-Ohio State), Elizabeth Hawkins (Ohio State), John Fulton (Ohio State), Kevin King (USDA-Agricultural Research Service), Ramarao Venkatesh (Ohio State) and Justin Koch (360 Yield Center). ●
Robotic irrigation.
Photo: 360 Yield Center
Mottech Water Solutions Ltd. and Viridix Ltd. have entered into a strategic partnership combining Mottechs’ remote control water management and irrigation application with Viridix’s Auto-Pilot precision irrigation system to bring their customers an autonomous, precision irrigation solution.
Mottech’s remote monitoring and control solutions ensure constant, reliable and accurate water usage, while reducing operational and maintenance costs. Mottechs’ ICC-PRO software is an advanced irrigation control platform that communicates with all the system’s components while simultaneously monitoring and controlling all sites, resulting in highly reliable,
centralized and remote irrigation management.
Viridix’s Auto-Pilot system is comprised of Viridix’s RooTense, a proprietary water potential sensor that provides real time data, and the company’s AI software that is in charge of aggregating the RooTense data with external data such as weather conditions and other inputs, and analyzing it all to provide operational insights, enabling the system to make and act on autonomous decisions.
Mottech and Viridix will co-develop a holistic solution, integrating Viridix’s Auto-Pilot system into Mottech’s ICC-PRO application. Customers will be able to monitor the root’s activity and implement a smart irrigation protocol across their farms in real time, field by field, adjusting irrigation levels according to real time conditions. The advanced system uses artificial intelligence to recommend the exact adjustments required to dose the optimum irrigation required for individual crops.
Mottech will be the exclusive distributor of the combined system in South Africa and Australia, while promoting the integrated solution in other territories as well. The full integration into Mottech’s ICC-PRO management software will be available in Q2 2022. ●