Ray Asebedo

Ray Asebedo, precision agronomist

Ray Asebedo, PhD, is an agronomist working in the field of precision agronomy. He helps growers determine the best practices to manage large farm fields by looking at smaller segments of their fields.

For example, if a farm has 160 acres, all planted with corn, it seems reasonable that all 160 acres can be managed the same way. But in the last few decades, researchers have found that it’s better to do site-specific management of crops. We use precision agriculture to do this.

What does site-specific management mean? Think of the way farmers manage how much nitrogen they apply to their fields. Plants need nitrogen to grow healthy leaves and stems, and for good crop yields. Some plants, like soybeans, can make their own nitrogen. But most, like corn, wheat, and sorghum, often need fertilizer to produce good yields to feed the world’s growing population.

Using site-specific management, farmers break up the 160 acres into individual smaller plots, sometimes as small as one acre. Then they look at the nitrogen needs of each individual acre. Researchers and practitioners help the farmers by using agricultural drones to survey the farm field. The drones collect information that accurately predicts the nitrogen needs of each plot.

How do the drones know what information to collect? Asebedo and his team have calibrated the drones to measure plant attributes that they have correlated to testing done in labs. In this way, the drone might “know” how much nitrogen a certain area of a field is lacking.

After flying the drone over a field and collecting data, researchers enter the data into computer programs in the lab. This gives a detailed report with nitrogen application recommendations for the farmer. A drone can fly over an entire 160-acre field in several hours. Farmers also scout their fields, usually walking through the field in a zig-zag pattern, sampling various areas. But it’s not possible for a farmer to look over an entire field, or to go out through the entire growing season. It’s easy to fly drones over crops as they get very tall–corn can get six feet or taller; sorghum over four feet tall! Walking through fields with mature crops measuring moisture or looking for pests is not easy.

Researchers from Asebedo’s team work with agronomists, who help growers implement specific recommendations based on their land. The grower implements these site-specific nitrogen recommendations in their field. That means that an acre on the northwest side of the 160-acre lot could get one dose of nitrogen, while another acre across the field could get much less–or even no nitrogen. This saves the grower money and helps the environment.

Homeowners and gardeners can apply these same techniques in their own yards by doing soil testing of different areas of their yard and garden. Homeowners probably don’t need as much fertilizer as they think! Contact a local extension for more information.

Site-specific nutrient management is just one way that Asebedo and his team are looking at solutions to feed the world and do it sustainably. Agronomists are committed to protecting the environment while making sure families around the world have nutritious, affordable food.

Watch Asebedo in action. Also, read more about using drones in agriculture.

To learn more about testing soil in your home garden, read the Soils Matter Blog, "What can I tell by looking at my soil?"

Ready to meet more scientists? Visit Agronomy @ Work.