Tuesday, September 21, 2021

“Drones” give birds eye view, make fast work for ag apps

By Veronica Coons

“Not all drones are created equal,” Dr. Kevin Price, a Kansas State University professor of agronomy and geography told the audience at the Wednesday noon presentation on drone technology at the Great Bend Farm and Ranch Expo.

The unmanned aviation vehicles (UAVs) Price spoke of at the Barton County Young Professionals sponsored demonstration have a completely different mission than Predator class drones used by the military for reconnaissance purposes.  Instead of gathering information about enemy locations, these small unmanned drones are being put to work gathering the same information in minutes that have taken hundreds of man hours of hands on work for ag researchers, farmers and agronomists to perform, and its being done comparably cheaply to boot.

KSU has been using the technology to pinpoint desirable breeds in test plots in minutes, a task that previously totalled 15,000 field hours.  Instead of having to harvest and test individual grains from several samples to determine which breeds had the genetic factors, a simple picture can tell the whole story.  An infrared camera can be attached to a drone, taking pictures with a one by one pixel resolution, sending the information to an onboard computer equipped with a spectroradiometer that  registers two wavelengths of colored light with one pass of the plane.  Since the human eye can’t see infrared light, the computer converts the image to near infrared pictures.  Healthier plants show up darker in the images because there is more chlorophyll present.

“The redder the picture, the greener the plant,” Price said.  Less chlorophyll is present when a plant is stressed, so disease or drought stress can be identified before it can even be seen by the human eye, he said.  Scientists in turn can rapidly tell which parts of the field to harvest, and which to destroy.

By taking a photo of an area and identifying certain plants, the infrared cameras can then use that information for determining different types of grasses in a pasture.

Price showed a near infrared photo of one invasive grass that is taking over the traditional prairie grasses in Kansas, Old World Bluestem.

“It’s estimated that we could lose 50 percent of the weight gain on cattle due to this grass becoming a monoculture,” Price said.  Drones can be used to assess range conditions, and also can make it apparent where overgrazing may be taking place. Not only can it identify the grass, it can also determine what the weight or other factors sought are in the stand.