Washington State Professor Lav Khot Finds Sky-high Opportunities for Drones in Agriculture

The work of researchers like Dr. Lav Khot is showing that we’ve only scratched the surface of what this relatively new technology can do for agriculture.

Khot works for Washington State University’s Center for Precision and Automated Agricultural Systems and in the agricultural automation engineering research emphasis area of the Department of Biological Systems Engineering.

Khot is involved with several projects that delve into how drones can help with many aspects of Washington’s diverse agriculture industry—from grapes, apples and cherries to winter wheat, potatoes, pinto beans and more.

One of the most prominent ways in which drones are used in agriculture is for thermal imaging. Multi-spectral sensors mounted on a drone can give users like Khot a good picture of how crops, specifically crop canopies, fare under different growing practices.

Khot is involved in the projects that look at how crops react to different irrigation techniques.

“We are, again, using drone technology to look at the stress that might be there in the canopy.”said 

Prof. Lav Khot 

While there’s an emphasis on the here and now in the drone industry—using drone imaging to help farmers make real-time decisions—Khot and other researchers are also using data gathered from drone cameras to see how certain crops, like potatoes and pinto beans, will respond to the climate of the future—one in which there will likely be less water for irrigation and warmer summer temperatures.  

For the pinto beans, Khot and USDA-Agricultural Research Service researcher Dr. Rick Boydston and his team are “reducing the irrigation level from the normal 100 percent to 50 percent to see which ones will survive the stress and which will not, and which will do better. We’re also looking at how tillage and no-tillage affect the pinto beans with the different levels of irrigation.”

In addition, Khot is looking at drones as a more efficient and cost-effective way to shake excess water off the canopies of sweet cherry trees after a seasonal summer rain. Fresh-market sweet cherries are a premium crop in Washington. 

When heavy rains come through, as they often do in June and July, the maturing fruit can split or crack. So growers will rent a helicopter—for about $20,000—to fly over the trees and shake the canopies and also Washington cherry orchards are not on flat ground, making it especially precarious for the helicopters and their pilots.

“We thought, why not try this mid-sized unmanned helicopter from Yamaha to see how efficient it is to remove the water from the canopies. We have found a good combination of flight altitude and travel speed to remove the water.”

One disadvantage is the size of the unmanned helicopter compared to a piloted-helicopter.

“Of course, the scale is not there. The big helicopter is about 30 feet in diameter and [the unmanned helicopter] is about 10-and-a-half feet. So you are looking at one-third of the coverage.”