Sentera, Inc., works extensively with agronomists to supply fixed-wing drones, imaging equipment, and software to get information quickly from a bird’s eye view to an agronomist and/or farm operator.

Their most recent offerings include weed ID, stand counts, and tassel counts via drone images.

“We build sensors, drones, and analytics that are custom-made to do exactly the kind of analysis of plants and fields that we want to do,” said Andrew Muehlfeld, Sentera director or Solutions Engineering.

In 2017, Sentera patented their first product, FieldAgent, which helps agronomists gather whole farm insights.

They have now patented Spot Scout, which can sub-sample fields with one or two measurements per acre. The multi-step process uses drone imagery to understand crop health and performance. With the development of Spot Scout, agronomists and farmers have access to stand counts, crop health, tassel counts, tree locations, canopy coverage, yield estimation, precision weed mapping, sustainability and custom analytics all with the help of a drone imaging system.

Headquartered in St. Paul, Minn., Sentera has customers in 74 countries, but works primarily in the U.S. Corn Belt. The company has 100 full-time employees with an additional 50 growing season employees.

“Our customers are sometimes farmers, but largely it is retail agronomists,” Muehlfeld said. “No one else does all the steps from building the sensor, to processing the imagery, to delivering it to an agronomist, and enabling the agronomist to share it with their growers.”

Sentera’s PHX RTK Payload, Double 4K – Analytics camera offers two types of digital images. These include NDVI (Normalized Difference Vegetation Index) and NDRE (Normalized Difference Red Edge) images.

So, in both cases, the images will not look like standard photographs but rather like color-coded digital maps.

For the tassel count program, Sentera engineers have programed AI technology to learn what a tassel looks like and pick them out of the image one by one. The information is then quickly counted and reported.

Obtaining tassel counts can provide a lot of information – a low tassel count may show where tiling is needed, compaction occurred, or may show the effects of weather or insect damage. A high tassel count can give a farmer peace of mind and help them estimate yield.

In terms of complexity, Muehlfeld suggested stand count is the easiest to complete, tassel count is more complex, and weed identification is most difficult of the three digital photo applications.

“The intent there is to enable growers to make herbicide selections, so if you know what kinds of weeds are in your fields, that will give you the ability to choose what herbicides to use,” he said.

While many people use quadcopter drones, Sentera manufactures and offers the PHX Fixed-Wing Drone. Their “airplane” weighs 4.2 pounds, has a 4.5-foot wingspan, and is just 2.5 feet long. It can cruise at 35 miles per hour with a maximum operating altitude of 18,000 feet above sea level.

Muehlfeld pointed out that drones are only allowed to fly up to 400 feet and are regulated by the FAA. A Remote Pilot Certificate, Part 107, is required to fly drones legally.

In some cases, a drone-licensed agronomist will fly a drone to take images, or they could hire a qualified pilot.

The PHX, Muehlfeld said, can scout 1,500 acres of non-contiguous fields in a day vs. about 500 acres for a quadcopter, according to Sentera research.

“The benefit of the fixed-wing is you can cover larger fields faster,” he said. “People who are providing professional drone data scouting services typically buy an airplane to cover big fields fast. If you are just scouting a couple of fields here and there, you might buy a small quadcopter.”

The high-quality images are easily sent digitally as they are about 5 MB each.

“These images can be imported into our software,” Muehlfeld said. “Then, those images could be shared with others at your company. You can ‘poke’ around and look for yourself at these images.”