June 15, 2021

Crop, pasture scouting goes aerial

URBANA, Ill. — Drones have transitioned over the past several years from a curiosity to crop and livestock production tool.

The benefits of using unmanned aerial vehicles on farms and ranches were the topic of an Illinois Nutrient Loss Reduction podcast hosted by Todd Gleason, University of Illinois Extension media communications specialist.

Panelists were Dennis Bowman, U of I Extension, interim assistant dean for ag and natural resources program and commercial ag educator specializing in precision agriculture and technology; Scott Erickson, Knox County farmer; and Teresa Steckler, Extension commercial agriculture educator specializing in ruminant production.

Dennis Bowman

How do you use drones in your current work?

Bowman: Drones are just a really great tool to extend your reach and your vision in the time of year when you can look at fields. One of the reasons I started investigating drones was to help out as a crop scouting tool, but also in my job as troubleshooting for crop problems, getting that big picture of a field, remote sensing imagery on demand any time you want it to collect the information and also to document things over time as things change throughout the season to get an idea where problems might be occurring and to develop a record of different things that could go on.

One of the research projects I’m working on is using drones to collect information about soybean varieties where we’re looking at the maturities of hundreds of different soybean lines. As they approach maturity we fly the drone every week and catch minor changes in colors as those different lines start to move in to maturity and document the maturity ratings and when the appropriate harvest time might be.

Are there conservation practices where you find that drones are useful?

Bowman: Water has such a huge impact on crops, both too little and too much. With too much water you can get potholes in the field and a drone is really handy for mapping out those wet spots and keeping track of them and also for the erosion side of water management. With the size of farms, the operator may not actual operate a combine or a tractor in all of the farms that they’re farming and cover every acre every year. Using a bare soil drone flight before the crop is planted or in the fall after harvest you can look for those areas and you can see where erosion is starting to occur and how extensive it is and you might not be aware that.

By taking a series of pictures as the drones fly over a field you can do a technique called photogrammetry. Even by just flying over a field and taking grids of pictures, computers can take those pictures and put them together into a three dimensional model.

You can build an elevation model that shows the erosion, the depth of the gullies, how extensive they are, and with certain software you can actually map out the volume of soil that’s been removed by these gullies. Or, if you’re going to do some construction practices to try to correct these things you can get an idea of how much fill might be needed to fix the problems.

Are there special licensing or rules related to using drones for agriculture purposes?

Bowman: If you’re going to use a drone for your business you need an FAA pilot’s license for unmanned aerial vehicles in order to operate that. The license is good for two years. You have to pass a fairly extensive test. There are several online courses or weekend courses that you can take that can get you up to speed pretty quickly with enough knowledge to pass the exam.

It’s not impossible to do yourself and there are a lot of free online sources you can use as well to get that information, but you do have to pass the exam, pay the fee, and every two years you have to take a recurrency exam to make sure you’re still up on all your knowledge. You need to be aware of what the laws are on how to use drones, where you can safely use them.

If you’re near an airport, that causes some problems, but by going through the education to get the license you learn the rules of where you can fly and how to go about getting approval if you are near an airport. If you have fields within five miles of an airport that operates commercial then you’re going to have to go through some extra hoops of permissions. You learn all about that as you go through the study guides for the exam.

Scott Erickson

Erickson grows corn and soybeans — 90% rotation, 10% continuous corn — and has a farrow-to-finish hog operation on the family’s farm. The operation is primarily no-till with some light chisel plowing on the continuous corn ground along a creek that runs through the farm.

Erickson: I bought my first drone four or five years ago for the same reason everybody does, just to see if I could take cool pictures around the farm. Now I use it a lot more for work than I anticipated.

We can have flood issues where the creek runs through and I got a better drone because I want to be able to fly over the creek line to see where it’s holding water or where water is coming out and we need to do some erosion control, or this farm is going to need tile because it seems like it’s holding water longer than others.

The creek has a deep bank creek and a lot of the farms are pattern-tiled, but there are some spots that you can tell when the water comes out it takes a little more of the bank with it every year and every couple of years we have to do some erosion control. It’s a lot easier to see that when the water is up and it’s definitely easier to see when I don’t have to wear mud boots and walk around trying to figure out where the water is coming out at. I’ve really like using the drone and it seems to help us out a lot.

Have you used it to see where wet areas might be in the spring to more easily locate the areas that may need tile?

Erickson: I took the drone up to look at emergence to try to see where the trouble spots might be on a farm that I did some cover crop on last year. When I had the drone in the air I could see some spots that from the air almost looked like drowned-out spots, but they weren’t, they’re just a little wetter than the rest of the farm. I took some pictures of that farm and sent them to my tiling company and they’re going to put some tile in just those spots whenever they get back around this area.

The biggest thing I use mine for is for farm ground that we rent or lease from a family member or landlord. I try to fly and take a picture every week once the corn is out of the ground, but I don’t always get it done. It will give you a pretty good idea of the progress of the farm and you don’t have to do that Sunday afternoon drive to see how things are doing on the farm.

What pointers do you have for farmers interested in using drones?

Erickson: The biggest thing is the government regulations and getting your license. It’s not hard to do. It’s not a tough test. It’s pretty much all common sense stuff, but you do have to jump through some hoops just like anything.

As for the actual flying of the drones, I had two of them. The first one was kind of a low dollar one, under $1,000. That’s still expensive, but it was hard to fly. It took some serious getting used to, to be able to do what I needed to do with.

The one I purchased last year is more technologically advanced and more money, but it almost flies itself. It’s definitely not anything to be afraid of. I don’t want to spend $2,000 on something and then not be able to fly it. There’s not a very sharp learning curve on the newer, nicer stuff.

Teresa Steckler

How do you use drones in your livestock research?

Steckler: I am currently trying to recruit cattlemen who need assistance with their pastures. We’ve had very poor spring weather the last several years in southern Illinois. The wet and cold weather didn’t lend itself to the growth of the forages very well, and we’ve had some very dry falls.

The culmination of all of this is a lot of overgrazing of our pastures. The pastures just haven’t had time to be rested and once you’ve had pastures that are over-grazed that lends itself to having invasive species or forages that are not very consumable for the livestock. You need to give these pastures time to recuperate and unfortunately a lot of these gentlemen just don’t have that option.

One of the things that I’ve been trying to do is get cattlemen to do at least more of a rotational graze. That way the grasses have somewhere between three to five days, maybe seven days, to recover from being grazed, and also working with them to spot spray.

One of the nice things the drones can do is instead of having to drive over the entire pasture we just fly over. It’s quicker, it’s easier and the cattlemen actually can get a whole different perspective and really target those areas and possibly set aside the really poor sections and work on those as far as spot spraying or bush hog.

It also helps us figure out the lay of the land, where the creeks might be and how we can work with waters, whether we need to take a wagon wheel approach or just make squares out of it, but figure out what’s the best layout that’s the easiest for the cattlemen to implement these changes.

Tom Doran

Field Editor