In the vast expanse of modern agriculture, where every innovation holds the promise of greater efficiency and yield, fertigation emerges as both a beacon of hope and a realm of challenges.
Jackson Stansell, founder and CEO of Sentinel Fertigation and a leading voice in the field, sheds light on the evolving landscape of fertigation. "Fertigation is such a niche market that very few people pay attention to it," he observes. "Some of the biggest work being done in fertigation right now can be divided into two areas: broadacre and specialty crop fertigation."
Jackson Stansell (pictured) says specialty crop fertigation is witnessing a surge of innovation focused on automation and precision.
Photo: Jacob Schlick, Saturn’s Lens, Lincoln, NE
Specialty crop fertigation, primarily conducted through drip systems, is witnessing a surge of innovation focused on automation and precision. Stansell emphasizes, "A lot of the innovation in specialty crop fertigation revolves around automation and increasing resolution. Instead of applying fertilizers in large blocks, we're now targeting smaller zones with valve automation, enabling precise nutrient delivery."
The concept of higher precision fertigation extends beyond specialty crops to encompass broadacre row and vegetable crops. Recent advancements, such as IoT-connected fertigation pumps, allow real-time monitoring and adjustment of flow rates and injection. Stansell highlights the significance of these technologies, stating, "There's an entire IoT component to fertigation now, revolutionizing how we manage and optimize nutrient application."
Moreover, there's a shift towards increased resolution in fertigation practices. Traditionally applied uniformly across entire fields, fertigation is now moving towards sector-based or even individual sprinkler-level control. This nuanced approach optimizes nutrient delivery, maximizing crop yields while minimizing waste.
Despite its potential, fertigation remains a largely untapped resource, with adoption primarily concentrated in specific regions. Stansell explains, "We primarily focus on Nebraska, where 85 percent of our business lies. Nebraska serves as the capital of fertigated corn, with roughly one-third of fertigated corn in the U.S. grown here."
Fertigation is now moving towards sector-based or individual sprinkler-level control.
Photo: Matt Sherman, Three Pillars Media, Lincoln, NE
Fertigation pros – and cons The advantages of fertigation are many, with its ability to offer a precise application window and timely nutrient delivery standing out as key benefits. Stansell elaborates, "Fertigation is the only practice that consistently allows farmers, especially corn farmers, to access the crop throughout its entire nitrogen use cycle. This ensures optimal nutrient availability from planting through the mid-reproductive growth stages."
Moreover, fertigation offers immediate incorporation of nutrients into the soil, providing plants with immediate access to essential elements. This contrasts with traditional fertilization methods, where nutrients may take time to become plant available.
Stansell says the most common formulations used in fertigation practices for commodity row crops (e.g., corn, wheat, cotton) are 32% UAN, 28% UAN, 28-0-0-5, 30-0-0-3, 25-0-0-8 and 12-0-0-26 (the fourth numbers in these analyses are percentages of sulphur). Specialty crops often use more unique formulations.
Fertigation is not without its challenges. High capital costs, labour and logistics pose significant hurdles for adoption. Stansell acknowledges these concerns: "Capital costs are a major complaint, along with labour and equipment degradation risks. However, these challenges can be mitigated with proper management and investment in newer irrigation systems."
Despite these challenges, fertigation is experiencing steady growth, driven by the promise of efficiency gains, profitability and agronomic benefits. Indeed, USDA statistics reveal an 18 percent growth in grain corn fertigation between 2013 and 2018, indicating a rising trend across various crops.
When it comes to crop selection, fertigation benefits a wide range of crops, particularly nitrogen-intensive and specialty crops. Stansell emphasizes, "Any crop can benefit from fertigation, depending on the nutrient applied. However, nitrogen-intensive crops and specialty crops that require consistent dosing stand to benefit the most."
Fertigation benefits a wide range of crops, particularly nitrogen-intensive and specialty crops.
Photo: Sentinel Fertigation
The future of fertigation Looking ahead, Stansell foresees fertigation playing a pivotal role in global agriculture. From Europe to Brazil, South Africa to New Zealand, fertigation is gaining traction in regions with coarse-textured soils and increasing irrigation needs. Moreover, emerging markets like Mexico and parts of the U.S. Corn Belt are witnessing significant adoption, driven by the need for efficient nutrient delivery systems.
As the world grapples with increasing drought areas, fertigation emerges as a viable solution, particularly in regions with high water availability and supplemental irrigation needs. Stansell explains, "Fertigation offers a practical solution to nutrient delivery in areas with high water availability but varying irrigation needs. It allows for precise nutrient application, maximizing efficiency while conserving water resources."
In conclusion, fertigation represents a paradigm shift in modern agriculture, offering a pathway to sustainable and efficient nutrient management. With continued innovation and adoption, fertigation holds the key to unlocking higher yields, profitability and environmental stewardship in the agricultural landscape of tomorrow. ●
Understanding and managing the nitrogen cycle in crop production is a complex task, fraught with uncertainties and variables that can confound even the most seasoned farmer. This is where decision support tools for nutrient management step in, offering clarity and guidance in an otherwise murky landscape.
Jackson Stansell, founder and CEO of Sentinel Fertigation, sheds light on the significance of these decision support tools.
"The nitrogen cycle is incredibly complex," he explains. "Nitrogen moves through the soil much like water, but it's even harder to manage because it can be sourced from various non-fertilizer sources such as organic material, irrigation water and atmospheric fixation. Making appropriate fertilizer application decisions without a decision support tool is exceptionally challenging."
In the realm of fertigation, where farmers have the flexibility to make frequent decisions about fertilizer application, the need for decision support tools becomes even more pronounced. Stansell elaborates, "Fertigation introduces many more decision events throughout a crop's lifecycle. While this can make things easier in some respects, it also adds complexity and uncertainty. Decision support tools for fertigation are crucial for consistently tracking crop and soil dynamics and informing decisions made throughout the crop's growth."
But why are these tools important for growers and irrigators? Stansell outlines four primary reasons: efficiency, profitability, productivity and confidence. "Using decision support systems helps farmers make better decisions, leading to optimal nitrogen application, maximizing profit, enhancing crop productivity and instilling confidence in their operations," he says.
Fertigation introduces decision events throughout a crop's lifecycle. Photo: Jacob Schlick, Saturn’s Lens, Lincoln, NE
Looking to the future, Stansell envisions decision support technology evolving to integrate real-time, site-specific information with crop growth models.
"The future of decision support technology lies in leveraging real-time data, such as imagery, sensor data, weather conditions and soil characteristics, to generate precise nitrogen recommendations," he predicts. "This fusion of data and modeling will enable farmers to plan effectively and make precise adjustments throughout the growing season."
As the agricultural landscape evolves, Stansell emphasizes the importance of efficient nitrogen management in light of environmental concerns. "Farmers will be expected to manage nitrogen more efficiently, both from a water quality and greenhouse gas emissions perspective," he notes. "This will necessitate mastering in-season applications to supply nitrogen at the right rate and time relative to crop need." ●
Nathan Bowen, IA Advocacy and Public Affairs Vice President
With the summer months upon us, it’s time for smart irrigation to take centre stage. Each year, the Irrigation Association shines a spotlight on the benefits of efficient irrigation and the wise use of water through its Smart Irrigation Month initiative celebrated in July.
Smart Irrigation Month is our opportunity to highlight the social, economic and environmental benefits of efficient irrigation technologies, products and services in agricultural, landscape and turf irrigation. We showcase the companies and professionals who share our commitment and responsibility to the efficient and effective use of our most precious resource: water.
The IA proudly presents “We are Smart Irrigation” as the theme for the 2024 Smart Irrigation Month campaign. This year we are celebrating the people in our industry who are embracing innovative irrigation solutions to safeguard our water future. We are honoured to recognize the efforts of everyone involved in the wise use of water, from engineers developing smarter systems to the growers, technicians, designers and contractors who deploy those systems.
For those in our industry, “smart irrigation” isn’t just a buzzword. It’s a necessity in an era defined by increased focus on freshwater resources. Smart Irrigation Month serves as a reminder of the important role that efficient water management plays in sustainable agriculture. In a world where water scarcity is an increasingly pressing concern, the adoption of smart irrigation practices is essential for preserving this precious resource while maximizing crop yields. Throughout July, the Irrigation Association leads efforts to promote awareness, education and advocacy surrounding smart irrigation, emphasizing the importance of precision and sustainability in water use.
Industry innovation driving change Innovation lies at the heart of efficient irrigation, driving continuous improvement and adaptation. Smart Irrigation Month celebrates the pioneering efforts of industry leaders in developing cutting-edge technologies and solutions.
By harnessing the power of data analytics, sensor technologies and automation, smart irrigation optimizes water usage, minimizes runoff and enhances plant health. From residential lawns to expansive agricultural fields, the benefits are manifold – conserving water, reducing operational costs and preserving ecosystems.
The precision irrigation landscape is rapidly evolving. Innovative technologies continue to drive efficiency and sustainability in irrigation practices. For example, the integration of machine learning and artificial intelligence enables growers to make data-driven decisions for improved water management. Predictive analytics models can forecast soil moisture levels, plant water requirements and weather patterns, empowering growers to adjust their irrigation schedules proactively and optimize yields.
The benefits of smart irrigation practices are vast and far-reaching. Through collaboration and investment in research and development, the industry is poised to usher in a new era of efficiency and sustainability.
Tell your smart irrigation story Smart Irrigation Month is our time to come together – as a global industry – to celebrate the best our industry has to offer.
The IA invites those in the industry to tell their story by sharing their thoughts on the value of efficient irrigation and what their company and teams are doing to promote smart irrigation practices and technologies through their business or in their operation.
IA staff in Virginia celebrating Tech Tuesday in July 2023 by wearing blue.
One highlight of Smart Irrigation Month and a way for everyone to be involved is Wear Blue Wednesday, taking place on July 17. On this day, you are encouraged to wear blue attire to show support for smart irrigation and raise awareness about the importance of water conservation in agriculture. By uniting in a visual display of solidarity, participants all over the world send a powerful message about the collective commitment to sustainable water management practices. Amplify your support by taking a photo; post it on social media and tag #smartirrigationmonth.
The Irrigation Association plays a central role in supporting stakeholders throughout Smart Irrigation Month. Free resources are available on the website, including social media templates, infographics and sample articles to equip individuals and organizations with tools to promote smart irrigation awareness and education. These resources empower stakeholders to spread the message of water conservation and inspire others to embrace smart irrigation practices.
From offering promotional discounts on irrigation technologies and services to starting a social media campaign highlighting the benefits of smart irrigation, Smart Irrigation Month is our chance to tell irrigation’s story to the world, sharing that not only the value that irrigation brings, but also reinforcing how our industry is driving the future of water management and efficient technologies.
We encourage you to browse the resources and ideas available at www.smartirrigationmonth.org.
Learn how you can use smart irrigation By leveraging technologies such as soil moisture sensors, weather-based controllers and precision irrigation technology, growers can optimize water usage, leading to significant water savings and improved crop health. Reduced water consumption not only conserves this finite resource but also reduces energy costs associated with pumping and distribution, contributing to overall farm profitability and sustainability.
Today’s irrigation industry offers myriad opportunities to take advantage of technologies and practices to improve the efficiency of your irrigation system. Now is the time to learn more and take steps to incorporate them into your operation.
We hope you will join us and be a part of “We are smart irrigation.” Together, let’s celebrate progress, engage in the present and innovate for the future.
For more information, a variety of resources and downloads, and ways to celebrate Smart Irrigation Month, go to www.smartirrigationmonth.org. ●
By Raney Rapp
From a thousand-foot view the recommended formula for increased on-farm soil health sounds surprisingly simple: cover crops plus reduced tillage equals more soil organic matter and greater water infiltration. For farmers in the Mississippi Delta hoping to preserve a unique legacy of highly productive soils and vast water resources, conscious conservation can be a bitmore complex.
“Rarely do we see increased infiltration rates in high residue management systems at a basic plot scale,” said Jason Krutz, director of the Mississippi Water Resources Research Institute. “When you roll it all the way up to a field scale, reduced tillage with cover crops compared to more conventional low surface residue systems had undetectable changes in water infiltration rates.”
Even in studies conducted over many years, the benefits of high residue cover crops combined with reduced or no tillage did not yield the results researchers sought. Extreme weather conditions made cover crop establishment and desiccation difficult. Even in years with good weather, good stands and good yields, the infiltration benefits, especially in highly productive silt loam soil types, did not emerge.
The ultimate answer was to try something different.
Subsoil science “That led us to do another experiment at the plot scale where we started looking at more subsurface disturbance, because what we thought was happening when we did eliminate a lot of tillage is that we started having compaction issues, particularly subsurface, which hindered the infiltration rates,” Krutz said. “We started looking at systems that we referred to as minimizing surface disturbance and maximizing subsurface disturbance with really narrow shanks dropped down 7 to 10 inches that would fracture plow plans allow greater infiltration rates.”
Jason Krutz, director of the Mississippi Water Resources Research Institute
At the research plot scale, eliminating the compaction with as little surface disturbance as possible improved infiltration rates relative to the control. With that initial finding, researchers realized they were on the right track.
“Silt loam soil seems to be especially susceptible, much more so than heavy clay soils that will crack so there's no problem with infiltration on them in the middle of the summer,” said MWRRI assistant professor Dave Spencer. “Silt loam soils, because of the different texture and the different properties that they have combined with the fact we’re no longer subsoiling to break up that compaction can have bigger issues with infiltration.”
Subsoiling – ripping up deep compaction under a field’s surface – was once a common practice at regular intervals throughout the Mississippi Delta. Today, as producers pursue conservation tillage and prepare fields with fewer field passes and fewer implements, the practice has fallen to the wayside.
“Subsurface tillage does a lot more for infiltration rates than I think anyone ever actually realized, especially the general public, because a lot of our producers have permanently abandoned the practice - probably less than 50% actually subsoil anymore,” Krutz said. “I think that that would be asimple technique to improve infiltration rates.”
Mississippi State research experiments typically centered around yearly subsoiling or ripping strategies, but Krutz said implementing the practice every 18 months to two years could still be beneficial for improved infiltration.
“Rarely do we see increased infiltration rates in high residue management systems at a basic plot scale,” according to Jason Krutz, director of the Mississippi Water Resources Research Institute.
Photo: Brent Murphree
Cover crops “We do recognize that having subsurface protection through surface residues does provide some of the benefits we're looking for,” Krutz said. “But it's not the whole answer. It's not the whole picture because there was deeper compaction that was still limiting our infiltration.”
Even when cover crop stands were well established and not limited by weather-related factors like dry autumns and early or late cold snaps impacting winter kill, soil conditions that limited cash crops simultaneously limited the benefits of cover crops.
“It makes sense intuitively that if the compaction layer is limiting infiltration and potentially the cash crops, it probably can limit the cover crop,” Spencer said. “We've seen things like until the root has grown down into the soil, it hits that compaction layer, and it starts pushing it above the soil. There will be several inches of the tuber sticking above the soil because they've encountered hard pack or it'll hit it and turn sideways. We haven't seen them be able to deal with that compaction.”
On large scale cover crop studies, benefits typically emerge over a long span of time. Krutz said even with as many as 15 years dedicated to research for cover crops in the Midsouth region, the evidence still does not support profound benefits.
“Sometimes we could see improved infiltration rates with the cover crops at a small scale but almost universally, we would see somewhere between $50 to $200 an acre loss in returns associated with cover crops on-farm,” Krutz said. “That's more for me as a research environmental agronomist to recommend.”
Above all, Krutz said research that happens on a small scale at the university level also has to perform on-farm from a standpoint of profitability and conservation.
“We are striving to make a production system that does what needs to be done,” Krutz said. “We don't need a lot of surface runoff. We don't need sediment, nitrogen, or phosphorus in lakes, streams and local reservoirs. We need nutrients to stay in place. We just refuse to continue to do the same thing and have the same effect – that is the classic definition of insanity.”
Raney Rapp is senior writer with Delta Farm Press
Reprinted with permission@Delta Farm Press,a sister publication toNew AG International underInforma PLC ●
Researchers at Michigan State University (U.S.) recently investigated if cooling blueberry fields with solid set overhead irrigation would protect blueberry bloom from extreme heat.
The scientists cite that increasing frequency and intensity of high temperature conditions during bloom is a potential risk for blueberry pollination. Some years ago, during a heat wave when temperatures exceeded 95 degrees Fahrenheit, the Michigan blueberry harvest was 30 to 50 percent lower than the previous prior, despite a “snowball” bloom.
As part of their research, scientists collected blueberry pollen from plants grown in the greenhouse and then exposed it to a range of temperatures between 50 and 104 F for four hours in an environmental chamber. The pollen was then examined under the microscope for its development after four and 24 hours to measure the percent germination and length of pollen tubes.
“Pollen development was slow at 50 F as would be expected during cool conditions, and it was optimal at temperatures between 68-86 F,” noted the research. In Figure 1, the yellow circle shows pollen at 86 F with pollen tubes germinated and growing. In red, the 104 F conditions have no pollen tubes. This shows that pollen has been almost completely inhibited from germination by four hours of extreme heat exposure.
Figure 1. Pollen tube growth from blueberry pollen exposed for four hours to 86 F (left) or 104 F (right) conditions, showing inhibition of pollen development.
“Between 86 and 104 F, we found that pollen performance steadily declined as temperatures increased, with substantial declines in pollen tube length at temperatures above 90 F (Figure 2). In a separate experiment, we also found that pollen exposed to extreme heat did not rebound and recover, so the effect is permanent.”
From these results, the researchers developed a warning model to integrate predicted bloom timings and predicted upcoming hot weather, posted for the first time this season on the Michigan State University Enviroweather website: Blueberry Bloom Estimates Model. This provides a colour-coded warning for conditions whenbloom is predicted to be underway and predicted high temperatures above 90 F.
“It is also worth noting that air temperatures over weed barrier fabric on sunny days can be five degrees hotter than fields with a weed-free strip, so those fields should be monitored more closely for temperature during heatwaves,” noted the researchers, adding a thermal temperature gun can be used to easily check field conditions.
If predicted field temperatures exceed 90 F, Michigan State University Extension recommends cooling fields if you have solid set overhead irrigation. These systems are typically used for frost protection and irrigation, and they can also prevent blooming fields from reaching the extreme temperatures that inhibit pollen growth.
“To test the effectiveness of this approach, we ran overhead irrigation in the blueberry planting at the Trevor Nichols Research Center in Fennville, Michigan, during bloom on May 30-June 2, 2023, with water applied for 15 minutes every hour (for five hours) once the air temperatures were expected to exceed 90 F.” The irrigation system dropped the air temperature by 10 F, with the evaporative cooling keeping air temperatures below the heat threshold where pollen damagewill occur.
“During the spring, the water temperature is also lower in ponds and likely assists with reducing the temperature in fields,” noted the researchers. “It is also important to mention that we have seen some evidence of damage to pollen from high temperatures during early flower development, so we recommend overhead irrigation during extreme heat even if the plants are not yet in full bloom.”
Current research is exploring potential downsides of in-bloom irrigation including greater risk of disease, and inhibiting bee activity. However, the potential benefits of saving the fruit set and berry size are expected to outweigh these concerns. “Reduced bee foraging is also during a small part of the pollination window and is likely to have negligible effect given that bees can still pollinate before and after the irrigation in the same day.”
This research was funded by the United States Department of Agriculture, Project GREEEN and by the Michigan Blueberry Commission. ●
When bees move pollen from flower to flower, it must be viable to achieve pollination by the pollen tubes growing to fertilize the ovaries. Photo by Rufus Isaacs, MSU
By Francesca Busuttil
An innovative irrigation method being tested in Gozo (second largest island in the Maltese archipelago) by local scientists could drastically reduce the amount of water needed to irrigate plants and trees.
The clay-based system involves placing clay elements close to the crops’ root zone. As the surrounding soil dries out, it creates a pressure differential and suction draws water out of the clay elements. The clay’s specific porosity controls the rate of water release, ensuring a slow and steady flow that caters to thecrops’ needs.
Researchers led by the Eco-Gozo directorate within the Gozo Ministry are testing out the technology – a variation of a Self-regulating, Low Energy, Clay based Irrigation (SLECI) system that is also being piloted in Portugal and Morocco.
The initiative is being implemented in three pilot locations: the Government Experimental Farm in Xewkija, as well as two fields in Għarb and Xagħra. Researchers are specifically studying two essential crops: vines and citrus trees.
In Għarb, researchers are using low water emitters (releasing less than1 litre of water per day) to irrigate vines. In Xagħra, citrus trees are irrigated using high water emitters (releasing less than 3 litres of water per day). Similar to the Xagħra pilot site, vines in Xewkija are irrigated using high water emitters (with a slightly lower capacity, releasing less than 2.5 litres of water per day).
Encouraging results are emerging from the initial trials at two of the Gozo sites, Għarb and Xagħra. Data
collection from the third site is still ongoing. While crop yields from both SLECI and conventional drip irrigation methods appear to be comparable, the water usage with SLECI is demonstrably lower. In fact, early data suggest that irrigation using SLECI technology requires approximately half the amount of water than in conventional drip irrigation.
Aside from reduced water consumption, SLECI systems also eliminate wasteful water runoff, minimise evaporation, help suppress weed growth thanks to their precise water delivery and promote nutrient retention by delivering water directly to the roots.
Furthermore, once installed, the system operates autonomously, providing water only when necessary.
Local researchers testing the SLECI system are doing so as part of the MED-WET project, which in Malta is funded by the Malta Council for Science and Technology through the EU-backed PRIMA initiative.
MCAST is a project partnerleading communication and dissemination efforts.
The MED-WET project is also running tests on the use of constructed wetlands in Egypt that treat wastewater for irrigation purposes, and on the use of a solar desalination greenhouse which uses renewable energy to convert brackish water to a new source of freshwater for irrigation. The latter project is also being piloted in Gozo.
The MED-WET project will conclude in October 2024.
Francesca Busuttil is a researcher working on the MED-WET project at MCAST. This article is brought toyou by the Malta Chamberof Scientists. ●
SLECI system.
Photo: MED-WET
Researchers from the Hydraulics and Irrigation group with the María de Maeztu Unit of Excellence in the Agronomy Department at the University of Córdoba (DAUCO) are working to apply data scienceand artificial intelligence (AI) technology to the field ofprecision agriculture.
An example of this is the HOPE project, which focuses on the development of a holistic precision irrigation model that also involves the application of AI to guide decision-making.
Within the framework of this effort, prediction models have been developed that would furnish irrigation communities with rigorous estimates of the amount of water that growers will need to meet their crops' needs.
The latest model developed, and the most accurate to date, makes it possible to predict the actual demand for irrigation water one week ahead and with a margin of error of less than two percent, thus making possible the effective management of resources, all without detracting autonomy from its users.
According to researchers Rafael González, Emilio Camacho and Juan Antonio Rodríguez, this advance represents another step in the line of digitization applied to irrigation developed by the AGR 228 Hydraulics and Irrigation research group. Now, they have applied the revolutionary architecture of Transformer Deep Learning to the field of precision irrigation.
“Since its appearance in 2017, this has been implemented in various sectors and is at the root of AI milestones, such as ChatGPT. The 'Transformer' architecture stands out for its ability to establish long-term relationships in sequential data through what are known as 'attention mechanisms’,” noted the researchers.
In the case of irrigation, this data architecture allows a lot of information to be processed simultaneously, delegating the selection and extraction of the information necessary for optimal prediction to its artificial neural network.
Daily data from the irrigation campaigns from 2015 to 2022 in the Zujar Canal's Community of Irrigators in Don Benito (Badajoz) were used to validate the results of this model. In total, more than 1,800 water consumption measurements were used to train the model, combined with data on temperature, precipitation, solar radiation, evapotranspiration, wind speed, humidity, crop types, etc.
This has reduced the margin of error from previous models from 20 percent to just two percent. “Applied to integrated decision-making support systems, this can be very useful for managers of irrigation communities by offering an accurate forecast of the daily demand for irrigation water for the next seven days in contexts of water scarcity and high energy prices, but also in the framework of a commitment to sustainable resource management,” noted the researchers.
The work is published in the journal Computers and Electronics in Agriculture. ●
DAUCO researchersEmilio Camacho, Juan Antonio Rodríguez and Rafael González.
