Virginia Tech researchers are pioneering efforts to bring drone spray technology to farmers’ fields, aiming to standardize unmanned aerial systems (UAS) for herbicide spray applications. This ambitious project is spearheaded by Vijay Singh, an assistant professor in the College of Agriculture and Life Sciences and a Virginia Cooperative Extension specialist at the Eastern Shore Agricultural Research and Extension Center. Singh’s initiative builds on his earlier groundbreaking UAS spray research, which was the first of its kind in the mid-Atlantic region.
In the United States, producers spend between $6 billion to $8 billion annually on herbicides. However, the repeated use of the same herbicides has led to the evolution of herbicide-resistant weeds, escalating costs for farmers. The need for additional practices and strategies to manage these resistant species has driven up expenses by $50 to $100 per acre. This, coupled with the rising costs of general crop production and labor in specialty crops such as watermelon, has created significant barriers to achieving higher returns.
Researchers have identified that enhancing spray efficiency, ensuring timely application, and adopting site-specific operations can effectively control weeds and significantly reduce herbicide usage. “Until recently, the use of UAS for weed management was limited to mapping and classification only,” Singh noted. “However, UAS-based herbicide applications have opened new opportunities to control weeds in areas inaccessible by tractors, in wet fields, and to manage late-season weed escapes.”
The project has received two grants totaling approximately $1 million from the National Institutes of Food and Agriculture. These funds will support not only the research objectives but also the demonstration of UAS technologies in producers’ fields, providing farmers with firsthand experience. The project team will evaluate different spray volumes, droplet sizes, altitude, spray speed, and large-scale spray operations. The Agriculture and Food Research Initiative grant will focus on the efficiency of blanket applications of both preemergence and postemergence herbicides in row crops. Meanwhile, the Crop Protection and Pest Management Program grant will target watermelon and other vine crops, streamlining the spot-spray operation process and evaluating precision and efficiency. Both projects will also involve an economic assessment of the proposed technologies.
“The testing of UAS is the first step, but the overall goal of these technologies is to automate the process and conduct real-time weed detection and spray applications, which we will achieve in the next few years,” Singh said. The team has previously collaborated with LeadingEdge Aerial Technologies and Homeland Surveillance & Electronics LLC for preliminary studies. With the expanded scope of the project, additional drones and UAS industry partners will be included.
The implications of this research are profound. By integrating UAS technology into herbicide applications, farmers can expect to see a reduction in herbicide usage, thereby lowering costs and mitigating the issue of herbicide resistance. Additionally, the ability to access difficult terrains and manage late-season weeds offers a significant advantage over traditional methods. This technological advancement promises to revolutionize weed management practices, making them more efficient, cost-effective, and environmentally sustainable.
As the project progresses, the agricultural community will be keenly observing the outcomes, hoping for a future where drone technology plays a pivotal role in sustainable farming practices.