The use of drones in agriculture is just the beginning

Drones can do a lot to help farmers or scientists, they can survey any area and even analyse what they see. In farmland, they can quickly track the spread of flooding, hail damage or even provide information on the health of crop cover.

Drone activity can of course also increase crop yields, which means more money for the farmer at the end of the day. Detecting problems as they arise and thereby preventing them from spreading also increases profitability.

Olga Walsh, at the University of Idaho, is looking at a rare use of drones, where she and fellow researchers have been investigating their role in fruit production. This is a relatively new field, as agricultural drones are commonly used in crop production.

“The introduction and use of crop drones in agricultural production saves thousands of dollars a year for many crops. Crop sensors also help to significantly improve the application efficiency of agricultural inputs such as fertilizers and water. And drones can minimize the negative impact of farming on the quality of our environment,” said Walsh. Idaho’s fruit industry grows mainly grapes, blueberries, apples and Asian pears. More than 27,000 tons of apples alone are produced annually.

“We knew that drones could be used in orchards. But there were no grower recommendations on what data to collect and what data would be most useful, depending on the grower’s objective.”

Monitoring seed set and seedlings is an extremely vulnerable stage in the life cycle of plants, which is particularly challenging due to their small size and lack of easily distinguishable formative characteristics. The time-consuming counting and grading of seedlings can be greatly aided by a technological approach that is both high-resolution imaging and fast.

The combination of UAVs’ high-resolution sensors and their low flight altitude allows the detection and recording of small deviations in any difficult terrain or remote area. When seeding, they can effectively cover large areas in the least possible time, even in areas where seeding would not be possible using conventional methods, for example due to soil conditions that are too wet.

According to research in Idaho, the most promising ways of using drones in orchards and nurseries could be:

• measuring tree height and canopy volume
• monitoring tree health and quality
• water, nutrients, pest and disease management in season
• estimating the yield of fruit trees and stone fruit
• creating marketing tools (videos to promote the orchard or to sell trees and fruit)
  
  “The ability of UAVs to provide high-resolution images is ideal for detecting various crop problems. They allow the scanning of crops from above. High-quality images and high-resolution spectral data are obtained. These are correlated with plant growth, health, water and nutrient levels and can be used to estimate biomass production,” said Walsh.

Not only are drones faster than we are when it comes to collecting data, but we can also equip them with detection devices and sensors that can provide farmers with data that was previously available only at very high cost through satellite surveys at very low cost.

“The sensors can operate in parts of the electromagnetic spectrum where the human eye cannot. They are also much more reliable and objective than visual assessment. They provide quantitative information (numerical data that can be measured and compared) as opposed to qualitative information (observable descriptive data),” the researcher added.

Walsh and his fellow researchers published the results of their work at the American Agronomical Society, the American Crop Science Society and the American Soil Science Society meetings in San Antonio.