As drones become more affordable and flyable, an increasing number of growers are kicking the propellers as they try to figure out how to implement this emerging technology on their farms.
The sky’s the limit in terms of the possible agricultural applications, but there is a limit to the amount of time and money farmers are willing to invest in a technology that doesn’t show a quick return on investment.
Drones were primarily used to take photographs when they first became available. However, they are now well past the gimmick phase in terms of agriculture applications, and they have proven their utility in research and in the field.
Whether acquiring a drone makes sense for your operation largely depends on how badly you want to implement the technology because it takes a considerable amount of time to learn how to turn them into a meaningful contribution.
For those who are considering acquiring a drone for their farm, here are 10 things to keep in mind:
1. How will it be used?
There can be considerable value in using a drone just to get an aerial view of the backside of a your canola field or to help locate livestock. If that is all you need the drone for, there are many affordable consumer drones with an RGB camera that can do this job effectively.
However, the real value of drones comes from their ability to produce data that helps growers make real time decisions, said Markus Weber, President of LandView Drones.
So if growers want to produce actionable data, they need to know what information their farm could use from a drone and then seek out a platform that best fills this need.
“In order to produce data, you need software, you need some machine learning, you need different kinds of cameras with different wavelengths of light. A bunch of things come into play,” Weber said.
2. Acres to monitor
The biggest thing to keep in mind when choosing a drone is the amount of acres that it will be covering, said Matthew Johnson, owner of M3 Aerial Productions.
“If they are covering a lot acres, then they might want to think about getting a fixed wing,” he said.
“If they are covering more than a few thousand acres, probably three or four thousand acres, I wouldn’t think a multi-rotor would be very useful at that point.”
However, multi-rotor drones, commonly called quadcopters, are more versatile than fixed wings drones.
“You can get a 400 foot aerial perspective, or you can get a four foot aerial perspective,” Johnson said.
“They can hover right over areas that you want to get a really close look at, take some pics with a high resolution camera.”
3. Selecting a sensor
There are many drones that can be programmed to survey a field, but it’s the type and size of the sensor or sensors with which the camera is equipped that determines the level of analysis that can be performed after a drone has flown a field. So it doesn’t matter if you own the flashiest drone in the municipality. It’s usefulness will be limited if you have only a tiny sensor.
“When you’re starting to select what you’re going to be flying, you want to choose something that gives you value from that sensor,” Weber said.
A drone equipped with an RGB camera would suffice if a grower were primarily interested in monitoring his crop’s emergence.
“But if you want to at midseason evaluate what parts of the field has the highest yield potential, for things like variable rate fungicide, then you’re already into things like variable light sensors to be able to do that,” Weber said.
4. Multispectral light sensor or converted sensor
Basic cameras, such as the one in your phone, are RGB (red, green, blue).
The sensors in these cameras are capable of seeing near infrared light, but it is blocked out be-cause they are taking images meant for the human eye.
“There is a whole industry that’s been built on converting those for crop imaging, and essentially all that is, is they remove the block for near infrared lights,” said Weber.
“And then in it’s place they block some of the visible spectrum light. Every conversion is different: some will block red, some will block blue. It all depends on the conversion. At the core of it is they are allowing near infrared light into a consumer sensor and then doing some calculations on that imagery to create that false colour image,” Weber said.
These converted sensors are the most commonly used by farmers and agronomists because they are the most cost effective at less than $10,000.
As soon as you get into multi-spectral sensors as a complete package, then you are talking up-wards of $10,000 for the aircraft, camera and the software,” he said.
“A multi-spectral system actually has separate sensors for each of the different wavelengths of light that it’s sensing.”
Most multi-spectral cameras will have a near infrared band, a couple visible light bands and something called a red edge.
“By breaking it down that way, you can do a lot more analysis on the data you’re collecting, you can do different vegetative indexes,” Weber said.
“With a converted camera, you’re basically stuck with one type of index.”
A multi-spectral allows the drone operator to work with other indexes that can specifically filter out soil or highlight crop stress because four different sensors are running calculations against each other, he said.
“This is the area people understand the least, and how can I put this nicely? This is the area where there is the most smoke and mirrors in the drone industry, where people will say you will see yield increases because you’ll see all kinds of things with this camera,” he said.
“It’s not really well understood, but it really is basic stuff.”
5. Data is collected, now what?
Learning how to program a drone to collect information from your fields is only part of the battle. Now you have to do something with this information.
“It doesn’t take long to pay it off if you are utilizing the data it produces and actually making decisions with it,” Johnson said.
“(However), a lot of the time data is collected and decisions aren’t made. It’s providing good data, but it’s not providing good savings.”
It’s important to know the limitations of how you can incorporate drone-derived data into your operation.
The largest savings that drones can offer is by helping collect information that helps growers make real time in-season decisions. Drones are often in the air because they are helping users make decisions. As a result, it’s important to not sit on the data. Process the information quickly, make a decision and move on.
Whether a grower can use the information in their sprayer depends on the software system that is in their sprayer and how it talks to their farm’s main software.
“It really is dependent on their equipment in their cab and what software they’re running, either in the cloud or their home computer,” Weber said.
“All of the systems that are out there right now produce something called a geoTIFF. So if the farmer is using FST or SMS or Ag Leader or John Deere Cloud or any of those, it’s a standard image that you can pull into any of those software systems.”
6. It’s all about the maps
Their remote controller may intimidate new drone users because they may fear smashing their brand new shiny unit into the first power pole it comes across.
However, they become less intimidated once they learn that they don’t have to take manual control of the drone and can instead just get it to fly a pre-programmed field map all by itself.
“People were amazed that they take off and land and fly the entire mission by themselves. So that ability of these consumer drones to be used for mapping is something that farmers should know about,” Weber said.
“Once I show them the mapping, a lot of them want to use it for elevation modelling or just for general mapping. Say they have some test strips and they want to see what the difference is between them from the air. There are a lot of those uses people can make of just a regular consumer drone, just by getting it into that mapping functionality.”
7. Pinpointing problem with that extra pass
Flying at high elevations is required for efficient field mapping, but you need to get it down to the crop level if you really want to know what’s going on at a specific location.
“After you’ve flown it at 400 feet to get a general sense of what’s going on, then you can go down closer to the areas that look like they are under stress so you can get some better resolution pictures,” Johnson said.
“The Sentara system allows you to, when you’re still at the field, process the NDVI images, which is pretty revolutionary.”
This means a grower can fly his field, figure out the trouble spots and send the drone out again to get up close to identify what is causing the problem, without having to fight through half a mile of canola.
8. Drones can help with variable rate, but it’s no soil test
Drones are often touted as a tool to help with variable rate fertilizer, but Weber said this isn’t a great use in Western Canada.
“When the variable rate occurs in the spring at seeding, we’d be better off using other data sources,” Weber said.
“Long-term yield indexing from satellite imagery or soil sampling is a better source than a UAV image.”
However, drones can be very helpful to determine fertilizer rates where split applying nitrogen is practised.
“In that scenario, it absolutely makes sense because you’re measuring what the crop response is mid-season and you’re basing your variable rate on that.”
When it comes to variable rate fungicides, NDVI (normalized difference vegetation index) images are used to determine what the yield potential is on different parts of a field.
“Then you can decide, where do you want to draw the threshold for where is there enough yield potential to make it worthwhile to put down the $25 bucks an acre,” Weber said.
“It’s more of an economic analysis. It’s not looking for disease and then going after the disease with the fungicide. It’s really just assessing whether it’s economically worthwhile to be applying products where you don’t have much yield potential anyway.”
9. Remember the other uses
There is a tendency in the agriculture drone world to start thinking that their uses are confined to dealing with crop health matters, but there are many other uses as well.
“Herding sheep works really well. Herding cattle, not so well,” Weber said.
“It really depends on the animal and their response to it. Some of them you can fly right up to them and they are just curious and stare at it. Whereas a flighty heifer will take off in any direction when you’re 100 feet away from them and you can’t control your direction at all.”
Drones can be useful when changing pastures to find the straggler cattle back in the bush and then to try flushing them out with a low, loud pass.
Elevation mapping is also possible, even for greenhorn drone operators once they install the right program.
However, crop health will remain a major use after the crop takes off because let’s face it, it’s a real pain to tramp around through a thick canola crop or tall corn stand.
“In Europe they use these to drop trichogramma wasp pellets into corn fields,” Weber said.
“It’s a beneficial wasp that will eat the corn borer larvae, so it’s an integrated pest management tool.”
There are also drones capable of carrying herbicides, and growers will soon be spot spraying weed patches without having to trample their crop.
10. You may not wed a drone to a paintball gun
This last tip should be about how it’s important to understand the federal regulations about drone use, but that topic is being covered in a separate story (see above).
Let’s just say that this last tip is about how an obvious practical use of drones in agriculture isn’t allowed.
Yes, you may want to mount a paintball gun on your drone to mark that sick heifer in your feedlot or to chase off the neighbour boy that your daughter has been finding a little too charming lately.
However, Transport Canada is not cool with the mounting of any kind of weapon onto a drone.