Key Takeaways:
- Remotely Piloted Aerial Application Systems (RPAASs) using low-drift nozzles at low spray volumes (1.0–1.5 gal/acre) achieved weed control comparable to traditional ground sprayers according to a study featured in WSSA’s journal.
- The study focused on large crabgrass control in turfgrass settings and tested multiple nozzle types.
- The research was conducted in 2022 at two sites in College Station, Texas, under field conditions.
- Results suggest RPAAS could be a viable option for site-specific herbicide application in turf.
- Further research is needed to evaluate RPAAS performance across more herbicides, weed species, and conditions.
New Research Explores the Role of Nozzle Type and Spray Volume in Drone-Based Weed Control
A recent study published in Weed Technology, a journal of the Weed Science Society of America (WSSA), has provided new insights into the effectiveness of Remotely Piloted Aerial Application Systems (RPAASs) for turfgrass weed control. Conducted in College Station, Texas, the research assessed how nozzle type and spray volume affect the control of large crabgrass using drone-applied herbicides.
The study indicates that RPAAS applications using low-drift nozzles and lower spray volumes (1.0–1.5 gallons per acre) can achieve results similar to ground-based applications at higher volumes (10 gallons per acre), offering a potential alternative approach for site-specific herbicide treatments.
Study Design and Methodology
Testing in Turfgrass Conditions
Researchers tested three nozzle types—extended range, drift guard, and air induction—mounted on a single-nozzle RPAAS. Two spray volumes were used in each treatment. For comparison, a four-nozzle boom backpack sprayer served as a standard ground application method.
“Applications using the RPAAS with the drift guard and air induction nozzles at low application volumes provided similar weed control levels as from the backpack sprayer at relatively higher volume applications,” said Muthukumar Bagavathiannan, Ph.D., senior author of the study and agronomy professor at Texas A&M University.
Evaluating Waterless Herbicide Applications
The researchers also examined a waterless herbicide application using an RPAAS and a flat fan nozzle, as well as an untreated control group. According to Augusto Costa, Ph.D., first and co-corresponding author and researcher at Embrapa Algodão, initial results show potential for applying undiluted herbicides via drone, though more testing is needed.
“While there are some indications from this research that certain herbicides can be sprayed using RPAAS without the need for mixing in water, further experimentation is needed for confirmation,” said Costa.
Next Steps and Considerations for Broader Use
Daniel Martin, Ph.D., of the USDA Agricultural Research Service, also contributed to the aerial application aspects of the study. The authors emphasized that more research is necessary to evaluate drone-spraying efficacy across different herbicides, weed species, and environmental conditions.
“Additional research would help us better assess RPAAS-based herbicide application efficacy across a greater range of conditions,” noted Bagavathiannan.
This study adds to the growing body of work investigating the role of aerial spraying technologies in precision turfgrass and agricultural management, with RPAAS showing promise as a complementary method for site-specific weed control.
Read the entire paper at WSSA’s webiste here.
