Using Drones to Track Differences Between Crop Varieties

A closer look at one seed and fertilizer retailer’s strategy for managing a soybean test plot

By Kaylee Fagan, Contributing Writer @DroneDeploy

When it comes to monitoring seed efficiency and crop performance, few people have to get in the weeds with the data as much as fertilizer and seed retailers, who must be able to identify and record the countless differences in performance within crop varieties, in order to help their buyers make cost-effective purchases based on their location, weather conditions, elevation, and other variables.

Which is why so many retailers have turned to drone technology in hopes of cutting down on time and money to assess early plant performance.

Rob Eggert, Seed Department Manager, TDS Fertilizer Inc.

Rob Eggert, who manages a seed, chemical, and fertilizer dealership in Northwestern Minnesota with TDS Fertilizer Inc., gave us an inside look at the complexities of retail farm supplies, as well as the advantages that drones can provide out in the field.

“What we’re looking for right now is long standing plant performance,” said Rob, whose recent focus has been on monitoring 24 different varieties of soybean seeds, four of which are still in the experimental stage, and have not yet hit the market. Rob is keeping track of numerous traits associated with each variety, including soil preference, early vigor, time to canopy, rain and fungicide response, and many more.

“With these maps, we can monitor the performance as it happens.” Rob says he was first fascinated by drones around four years ago, when he saw maps and photos being taken by other farmers.

“The maps are so much better than a picture,” Rob said. “It’s like being able to see your farm from a 10,000 foot altitude, but also being able to zoom in to two inches above the plants. There’s no other system that can do that.”

Mapping Progress

This year, Rob has been mapping his soybean test plot every week to keep a close record of which varieties are succeeding, and which are not.

Map taken on June 28, 2016. Click here to explore.

“After I got the first map, decided I was going to fly it every week just to see the sheer contrast between the rows. When we do take this to harvest, we’ll have a weekly log of what the crop was doing throughout the growing season.”

After processing the second map, Rob could see the significant progression in plant growth that had occurred over only eight days:

Map taken on July 5, 2016. Click here to explore.

Rob then saw a similar improvement a week later, when the color of the plants became even more vibrant:

Map taken on July 18, 2016. Click here to explore.

These photorealistic maps clearly showed growth over time, but to quantify growth and highlight variations between the test rows, Rob used the VARI vegetation index, available as part of DroneDeploy’s plant health tools. VARI is similar to NDVI in that it interprets imagery to highlight variations in plant health, but it is different in that VARI is intended for visible spectrum cameras, while NDVI is intended for near infrared (NIR) cameras. Both indices calculate a value for each pixel in the map ranging from -1 to 1. A higher, positive index indicates healthy, green plant material, while a low or negative range denotes less plant matter, and therefore unhealthy or dying plants.

Each time that Rob mapped the field, the plant health index increased in value, which indicates that the plant performance had improved across the test plot.

Some rows performed better than others, and the VARI index helped highlight these differences. The row highlighted in blue improved each week and stands out as the row with the most green, healthy vegetation, while the experimental row highlighted in yellow performed relatively poorly throughout the three week period.

It’s All in the Details

This record allows Rob to isolate each event that takes place on the field and record exactly how each variety reacted. For example, if a variety starts to suffer the week after a heavy rain, Rob can identify that change and will be able to better advise customers which variety to purchase based on their location, soil type and planting time and other factors. He can test the effectiveness of different seed treatments, and how different varieties respond to them. He also hopes to record the plants’ reactions when fungicide is introduced into the field later in the season.

Doug Miller and Mark Benson of TDS Fertilizer, Inc., vacuuming out the planter units and loading the next variety of soybean seed

In addition to tracking how varieties respond to specific events, Rob is also closely monitoring long-term trends, in order to recommend the best product for his customers. For example, some soybeans are bred to mature quickly so that growers can rotate multiple crops in the same season, while others are bred to mature slowly but offer higher yield. Therefore, plant maturing time can be a crucial deciding factor for customers, and it’s imperative that seed retailers like Rob can give them an accurate estimate of when the soybeans will mature.

“The ultimate goal is to find out what’s going to grow best where,” Rob said, “The maps are telling us — right away — which varieties are going to be great in those conditions.”

Saving Time During Inspections

Before Rob began incorporating drones on the seed test plot, several people would have to walk the field in a single line at different intervals and visually assess each plant, and then give a rating from one to ten for numerous characteristics like emergence, first pod height, and final yield.

“Now one person can do the job of four people, giving me more benefit from each visual check,” said Rob.

Rob says that now, the maps he collects on a weekly basis allow his staff to see how each variety is progressing, even before stepping foot on the field. He explained that since incorporating the maps into his usual workflow, the people giving the ratings know exactly what to look for in each row. “The map essentially shows me where to go. If there’s a red spot, we can go investigate and see why it’s red,” he said.

Plenty of Room to Grow

“We’re finding more and more uses for these maps every day,” said Rob, when he mentioned he is looking forward to creating variable rate prescription maps for TDS’s customers and exploring applications in cover crop test plots.

Rob’s Phantom 3 Pro

Seed and fertilizer retailers have a wide variety of data to collect and analyze for each field, crop, and variety they sell. Numerous patterns, traits, and reactions to both natural and man-made environment changes must be monitored and communicated to customers. While all these variables may seem daunting, Rob has found that drone technology and DroneDeploy can help simplify the process.

Where to Learn More

To learn more about using drones in agriculture, join us for a free webinar this Thursday, August 18 at 1 pm Central Time with experts Jim Love of Beck’s Hybrids and Chad Colby of Colby Ag Tech. For more information about specific topics, check out our support center:

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DroneDeploy's Blog

DroneDeploy is the leading cloud software platform for commercial drones. Learn more at


Written by

DroneDeploy is the leading cloud software platform for commercial drones.

DroneDeploy's Blog

DroneDeploy is the leading cloud software platform for commercial drones. Learn more at

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