Geospatial AI provides new avenue for forest health research

By Nick Kordsmeier
U of A System Division of Agriculture 

MONTICELLO, Ark. — While an emerging fungal disease continues to chip away at the forestry industry in the southern United States, remote sensing researcher Hamdi Zurqani is developing artificial intelligence models to seek answers from the skies.

UNMANNED AIRCRAFT — Hamdi Zurqani, remote sensing researcher and assistant professor for the College of Forestry, Agriculture and Natural Resources at University of Arkansas at Monticello, inspects a drone outfitted with a LiDAR, or light detection and ranging, system. (U of A System photo courtesy of Zurqani.)

“My job is to identify different stages of mortality,” said Zurqani, assistant professor for the College of Forestry, Agriculture and Natural Resources at the University of Arkansas at Monticello. Using aerial imagery obtained from drones, Zurqani said he is developing tools that give landowners and other stakeholders the information they need to manage this growing threat to the forestry industry.

By applying geospatial artificial intelligence techniques, Zurqani said he can assess how many trees have been affected by the disease. “How many trees have already died? How many trees may be in the early stage that are going to get worse? How many trees are still green?” he said.

Since summer 2022, foresters and researchers have been fielding calls about pine decline in Arkansas. Pine decline is a convergence of environmental and genetic issues that cause tree health problems in pine forests. Results from diagnostic tests in July 2023 confirmed that a fungal disease called brown spot needle blight is at least partially to blame.

“It's kind of nipping away at pine forests,” said Michael Blazier, director of the Arkansas Forest Resources Center and dean of the College of Forestry, Agriculture and Natural Resources. “Although there are pockets of dying trees within affected forests, a bigger issue could be slower growth of infected forests.”

Blazier said that when trees lose their foliage, as often happens with the needle blight disease, they have less energy to invest in growing their trunk diameter. Less trunk growth means less wood production and delayed harvest.

DETECTED — Aerial imagery of pine forests from remote sensing researcher Hamdi Zurqani are used in an AI model under development. The top photo shows a section of pine trees in southeast Arkansas impacted by disease. The bottom graphic shows part of the output from the AI detection approach, which shows living trees in green and dead trees in brown. Red boxes have been added to show corresponding dead spots. (U of A System photo courtesy of Zurqani.)

Understanding the how and why of brown spot needle blight remains the primary focus for researchers in Arkansas and the wider region, Blazier said. That’s where Zurqani’s work comes in.

“If we were able to identify the early stages of the disease, we can somehow get a clue about what’s going to happen in the future,” Zurqani said.

In Arkansas, Blazier said the fight against pine decline has been highly collaborative. The Forestry Division of the Arkansas Department of Agriculture and the Arkansas Forestry Association have been working closely with the Arkansas Forest Resources Center, which conducts research and extension activities through the Arkansas Agricultural Experiment Station and the Cooperative Extension Service, the University of Arkansas System Division of Agriculture’s research and outreach arms.

“We have a tight working relationship between all of those agencies,” Blazier said. “There’s been excellent communication between the university, extension service, forestry association and the state’s forestry division.”

Regional challenge

In August 2023, Blazier attended a meeting at Auburn University to discuss the needle blight phenomenon with researchers and industry stakeholders from across the southern U.S.

According to information from the U.S. Department of Agriculture’s Forest Service, brown spot needle blight has been confirmed in nine states, including Alabama, Arkansas, Florida, Georgia, Louisiana, Mississippi, South Carolina, Tennessee and Texas. Severe damage, however, has so far been limited to Alabama, Arkansas, Louisiana and Mississippi.

The meeting was organized by Lori Eckhardt, professor and director of Auburn University’s Forest Health Cooperative.

“I organized this meeting to bring together industry, government, academia and private landowners to create a space in which attendees can discuss questions, brainstorm ideas, identify problems and make decisions and develop solutions pertaining to brown spot needle blight,” Eckhardt said.

“Collaboration is important between the researchers and the landowners,” she said. “The day-to-day managers in the field can share knowledge that assists us as researchers in asking good questions to design studies that better help us understand and manage the disease. Working together will help us find answers sooner.”

Collaboration leads to clues

Blazier said the Auburn meeting provided an opportunity for participants to share what actions each affected state is taking on the research side to understand what’s causing the problem.

“One of the things that was shared at the Auburn meeting was some anecdotal evidence from the forest industry showing that there may be a soil nutrient facet to this,” Blazier said. “And that's actually something that we are looking into further within the Arkansas Forest Resources Center.”

Researchers have been collecting samples this winter from stands of trees affected by pine decline and analyzing nutrient levels. If a nutrient deficiency is found to contribute to pine decline, Blazier said that targeted soil fertilization might be a way to fight the disease.

“And that would actually give us another tool,” he said.

Looking to the future

As the winter dormant season ends and the life cycles of fungal diseases pick up again, Blazier said that testing for pine decline will continue next month.

“We’re going to resume testing on a monthly basis as a group in February, and we’ll continue that all the way through the growing season,” he said. That information will continue to feed into Zurqani’s research efforts using geospatial AI.

Blazier sees hope for spatial analysis and machine learning tools to help researchers identify patterns in the data and get to the bottom of pine decline.

“We're really optimistic,” he said.

To learn more about Division of Agriculture research, visit the Arkansas Agricultural Experiment Station website: https://aaes.uada.edu/. Follow us on Twitter at @ArkAgResearch. To learn about extension programs in Arkansas, contact your local Cooperative Extension Service agent or visit www.uaex.uada.edu. Follow us on Twitter and Instagram at @AR_Extension. To learn more about the Division of Agriculture, visit https://uada.edu/. Follow us on Twitter at @AgInArk.

Drones in agriculture research propels multistate award

By John Lovett
University of Arkansas System Division of Agriculture

FAYETTEVILLE, Ark. — Unmanned aircraft flying over farms, forests and plant nurseries are not such an unusual sight these days. A lot of research has gone into making the drones more economically beneficial in agriculture, from taking inventory at plant nurseries to spotting early signs of crop stress.

DRONE TECH — Collaborative research across many states within the Association of Public and Land-Grant Universities has helped adapt drone technology as an agricultural tool. (U of A System Division of Ag photo by Fred Miller)

The University of Arkansas System Division of Agriculture’s research and extension arms were among the institutions recently recognized for drone research and outreach with the National Excellence in Multistate Research Award from the Experiment Station Section of the Association of Public and Land-Grant Universities’ Commission on Food, Environment, and Renewable Resources.

The award recognizes experiment station scientists who are conducting “exemplary research and outreach efforts across multiple states” for unmanned aircraft system applications in U.S. agriculture and natural resources. Scientists from 23 institutions across the nation share the award for their contributions to the project titled, “Research and Extension for Unmanned Aircraft Systems (UAS) Applications in U.S. Agriculture and Natural Resources.”

The project is supported by the State Agricultural Experiment Stations from the Hatch Multistate Research Fund provided by the U.S. Department of Agriculture’s National Institute for Food and Agriculture.

Jim Robbins (U of A System Division of Agriculture photo)

Jim Robbins, a recently retired horticulture professor and extension specialist with the Division of Agriculture, was among the authors of agricultural drone research projects recognized in the award. He took part in studies that measured the accuracy and efficiency of drone-based systems for inventory in nurseries using RFID (radio frequency identification), as well as using cloud-based artificial intelligence software like IBM Watson Visual Recognition to identify early indicators of water stress in row crops.

Robbins conducted outreach work for the Arkansas Cooperative Extension Service and research for the Arkansas Agricultural Experiment Station.

Randy Raper, administrative adviser for the multistate drone research program, said collaboration between researchers across the country has been key to adapting the new technology to agricultural uses. Raper also serves as assistant vice president of facilities for Oklahoma State University and assistant director of OSU Ag Research.

“One thing we saw with this committee is that we have people very versed in different areas,” Raper said. “We have people who are astute in flying the UAVs and then others who are interested in sensors, and others who apply the research. Every institution can’t have experts in every area, so collaboration has been very important to shepherding this technology.”

He compares the emerging technologies and applications of UAVs to the RTK-GPS tractor guidance systems that emerged in the early 2000s and have now become universally adopted. Satellite imagery was also being used to analyze crop production before UAV systems gave advantages to researchers, he said.

“Satellite images can be problematic because of cloud coverage, and what we are looking at is time sensitive,” Raper said. “UAVs and UAS technology allow you to have more control. You can collect the data and make rapid decisions on how you want to treat it. This naturally fits into the management we recognize.”

Numerous researchers working together have enabled the committee to get the technology to where it is today, Raper said. Annual meetings between researchers across the country allowed for the exchange of ideas and experiences using the UAVs to open potential for further applications. For example, he said researchers in the Northwest experimented with using UAVs for spot pesticide application in orchards. This inspired researchers from other parts of the country to explore related applications in other crops.

Gary Thompson, executive director of the Southern Association of Agricultural Experiment Station Directors, noted that this southern region multistate project has direct impacts for agricultural producers.

“Landscape-level management decisions are increasingly reliant on obtaining accurate and reliable data that can be analyzed in real-time,” Thompson said. “Remote sensing with drones provides a versatile means of getting high-resolution information to agricultural managers. I am excited about the work of this group of researchers and congratulate them on this well-deserved recognition.”

Thompson said that the association administers this ongoing southern region project, which focuses on challenges in the southern region while being open to participation from institutions across the nation.

The “Research and Extension for Unmanned Aircraft Systems (UAS) Applications in U.S. Agriculture and Natural Resources” multistate project committee is made up of scientists in Alabama, Arkansas, Florida, Georgia, Indiana, Illinois, Kentucky, Louisiana, Mississippi, Montana, New Jersey, New York, North Carolina, North Dakota, Oklahoma, South Carolina, Tennessee, Texas, Virginia and Washington.

“Over the past five years, this project has evaluated and identified reliable, cost-effective, and user-friendly drone platforms and sensors for monitoring and managing stressors in agriculture and natural resources,” the Experiment Station Section award noted. “To maximize the accuracy of the data collected, project members have developed hardware, software, and detailed protocols for calibrating and using drones. New drone-based strategies are helping address many different issues in agriculture.”

The Southern Association of Agricultural Experiment Station Directors represents 15 agricultural research centers at land-grant universities in the southern U.S., where scientists collaborate to conduct research and outreach focused on conserving the region’s natural resources and sustainably feeding a growing global population.

To learn more about Division of Agriculture research, visit the Arkansas Agricultural Experiment Station website: https://aaes.uada.edu. Follow on Twitter at @ArkAgResearch. To learn more about the Division of Agriculture, visit https://uada.edu/. Follow us on Twitter at @AgInArk. To learn about extension programs in Arkansas, contact your local Cooperative Extension Service agent or visit www.uaex.uada.edu.