Improving the sustainability, efficiency and environmental impacts of crops, water and cattle requires precise decisions.
Researchers at Oklahoma State University are focused on how technology and science can aid in that process.
“The whole goal of precision ag is improving efficiencies — efficiencies of input and output — and to be more sustainable both economically and environmentally,” said Dr. Brian Arnall, professor and OSU Extension specialist. “The purpose of most precision ag technologies is to put the right amount of something in the right place at the right rate at the right time. We need data and information to do that, and that’s what precision ag is — using data and information to make management decisions.”
Arnall, a specialist in precision nutrient management, and his colleagues are trying to find better ways to identify what nutrients soil needs. They are especially focused on phosphorus (P) and potassium (K) fertilizers in soil, conducting their tests through soil testing with sensors and remote imagery.
The research began in the fall of 2022 with researchers applying P and K fertilizer strips on wheat and soybean fields to determine if there are technologies that do a good job of predicting crop needs.
But technological innovations in precision agriculture at OSU don’t stop with crop management. OSU and the Oklahoma Water Resources Center are working hand-in-hand to not only make cattle production more efficient but to also improve the health of Oklahoma’s water resources.
OSU researchers took their research on virtual fencing technology to the next level in the fall of 2022 with a $1.4 million grant from the U.S. Department of Agriculture-Natural Resources Conservation Service.
“We’re looking at how managed grazing with virtual fencing can improve grazing distribution, pasture biodiversity and productivity, and wildlife and pollinator habitat,” said Dr. Ryan Reuter, professor of range beef cattle nutrition in the Department of Animal and Food Sciences.
The technology was introduced in 2019 during a pilot project. There, researchers observed where a group of cattle liked to congregate for two weeks before implementing a virtual fence and exclusion zone on that spot for about 10 days. The experiment resulted in a 99% success rate at keeping cattle out of that zone.
The current phase of the research is studying the grazing habits of cattle in riparian zones — areas bordering bodies of surface water — and upland areas — land at a higher elevation.
The team hopes to learn how much time the cattle spend in areas preferred by researchers versus how often they move into areas researchers want them to avoid. The study will also show how virtual fencing improves the grasslands environment where cattle graze.
“We’ll have an exclusion zone around the riparian area so they can’t get down in the creek, and we will do some rotational grazing where we move cattle around the pasture to control their grazing patterns,” Reuter said. “We’re going to look at whether the water runoff quality improves when we do that.”
Improving Dam Infrastructure
Many dams in Oklahoma are reaching the end of their planned life spans.
One year into a five-year project to improve dam infrastructure, U.S. Department of Agriculture and Oklahoma Water Resources Center scientists are adding some high-quality tech to their tool bag.
“These dams are still considered quite safe, but due to the number of these structures and their planned service life coming to an end, we need to be vigilant in monitoring them and develop cost-effective rehabilitation options so communities can continue to benefit from these structures for years to come,” said Sherry Hunt, supervisory civil engineer for the Hydraulic Engineering Research Unit (HERU) with the USDA-Agricultural Research Service.
Oklahoma dams provide $90 million in annual benefits to residents, Hunt said.
“These dams are located on the upper tributaries of small watersheds and provide flood protection, rural and municipal water supplies, irrigation water, healthy ecosystems, and recreation and tourism,” Hunt said.
At HERU, researchers design miniature versions of these flood control structures made of natural earth materials and run water over them or through them to see how the dams hold up.
The USDA and OWRC partners are developing tools to assess dam erosion and stability. These tools include artificial intelligence, drones and smartphone applications that can predict future issues with earthen dams.
Another aspect of the project entails creating a cloud-based storage system for the sensor data collected and making it available to researchers and decision makers on a continuous basis. Researchers are also developing an app to go with the cloud system as a streamlined way of viewing the data.
The Oklahoma Well Owner Network Program
Oklahoma well owners are on their way to healthier drinking water thanks to the Oklahoma Well Owner Network (OWON) Program.
The program, led by the OWRC and OSU Extension, provides free residential well water testing and training to rural counties in Oklahoma.
“In 2018, we surveyed citizens across Oklahoma on what their biggest water resource concerns were,” said Dr. Kevin Wagner, OWRC director. “Consistently across the state, Oklahomans’ key concern was drinking water quality.”
To address this concern in rural Oklahoma, OWRC conducted a pilot program in Alfalfa, Pontotoc and Tillman counties in spring 2022 with the help of OSU environmental science students. Over 150 water samples were tested during the pilot program, and two-thirds of participants said they planned to adopt annual well water testing.
Senior environmental science student Rayna Ellison said she conducted the research in her hometown during the pilot program. Then, in the summer of 2022, OWRC partnered with the OSU Rural Renewal Initiative to expand services to Greer, Tillman and Harmon counties, along with training and teaching experience for Ellison. OWRC and OSU Extension hope to obtain additional funding to continue the program into 2023.
“The citizens who participated in the program were grateful to have access to water quality information, and they were coming back with questions on how to improve their water and began working to improve their wells in the weeks following the program,” Ellison said.
To participate, well owners in these counties submit a water sample from their private wells to their local OSU Extension office for testing. OWRC researchers then test the samples for nitrates, total dissolved solids (salts), pH levels and bacteria. The test results are relayed to the well owners through a one-hour, in-person educational program led by OSU students and OWRC staff.
“This program demonstrates OSU’s land-grant mission in the terms of Extension, ag research and education,” said Dr. Abu Mansaray, a research specialist with OWRC, who has been part of the planning and execution of the program. “We are reaching out to Oklahoma communities to help address a critical problem that is not covered by federal and state agencies.”
Irrigation Management Research
Knowing when crops need water can be difficult, but technology may help make those crucial decisions easier.
In collaboration with faculty, students from the OSU Department of Biosystems and Agricultural Engineering recently completed a study to evaluate the effectiveness of common soil moisture sensors.
The Oklahoma Water Resources Board predicts that crop irrigation will make up 36% of the total water demands in 2060.
The goal was to determine the effectiveness of smart irrigation technologies — such as sensors and other WiFi-connected devices.
These sensors were designed to be affordable while still providing highly accurate readings. The sensors mount in the ground and connect to a data logger that sends their data to a cloud-based storage system.
To test the sensors, the team monitored soil moisture in cotton crops for two growing seasons. Researchers also collected soil samples and analyzed them for bulk density, soil moisture content, texture, salinity and soil moisture thresholds. This allowed for a comparison of the two methods.
“Specifically, we wanted to see what the water content was in those samples so we could compare them to the data being taken by the sensors,” said Mukesh Mehata, biosystems engineering graduate student. “By doing so, we could see how accurate the sensors are.”
The results showed that the sensors were effective in monitoring soil moisture at multiple root zone depths. However, their accuracy degraded rapidly as the clay content and salinity increased in the soil with as high as 30% error in these conditions. The main finding was that the sensors are effective when clay content and salinity are low, but site-specific calibration is required as those and other factors increase.
“We can’t ask producers to adopt technologies that are inaccurate and too expensive,” said Rio Bonham, a senior in biosystems engineering. “We feel confident a producer can put these in the ground, and with proper calibration, they are not going to over or under water their fields.”
Continuously looking for ways to improve the efficiency and output of agricultural production through the use of technology will not stop there for OSU, according to Dr. Scott Senseman, associate vice president of OSU Ag Research.
“In my view, agriculture has always been more technical than it has been given credit for, but agriculture in 2022 is even more technical,” Senseman said. “The use of advanced genetics, along with management of crops using drone technology and the creation and analysis of large data sets is another realm of advancement in ag technology.
“Our land-grant university is right in the middle of technological advancements and helping our producers incorporate these advancements in their production systems.”