MFPC Special Report: How drones are changing forestry
When Regional Forest Ranger Jeff Currier first suggested that the Maine Forest Service explore using drones, he sold the idea with a scenario everyone who works in the woods fears and many have experienced. Driving past or walking through a forest and thinking, “I smell wood smoke.”
Tracking that smell is tough, especially when the sun is setting, the wind drops and it’s too late to call in a helicopter. The traditional response, Currier said, was to walk through the woods, sometimes for hours, trying to locate the smoke’s source. Now, there’s a more high-tech option.
“With a drone and georeferencing of the photos and the video,” Currier said, “I can take a GPS point and say, ‘OK, ranger, plug these coordinates in and walk directly to it.’”
Currier has a 17-second video (above) illustrating that exact scenario. Lightning ignited a fire that rangers could smell, but not see. Currier sent up a drone, panned 360 degrees, spotted smoke, flew the drone to it and pointed the camera down at a small fire.
“Every fire starts small, so we want to kill them quick,” Currier said. “It’s just incredible how much time the drone saves. How much energy it saves. How much smarter we can be. It’s a really great tool. And this is just the beginning.”
In Maine, drones already are contributing to sustainable forest management plans, monitoring harvest operations, finding forest fires, tracking invasive insect infestations, search and rescue, and much more.
“Right now, we’re using UAVs to help identify wet areas that need to be checked ahead of spray operations and to monitor active harvest operations for BMPs and utilization,” said Chris Fife, Weyerhaeuser’s public affairs manager for Maine, New Hampshire and Vermont.
Drones are often referred to as unmanned aerial vehicles (UAVs), which refers only to the aircraft, not the ground control and communications units, or unmanned aircraft systems (UAS). They’ve been around a lot longer than you might think. As with many technologies, the first uses were military, including development of the first machine that today’s users might recognize as a drone, which dates to 1907.
Think of Maine’s 17.6 million acres of forestland – as well as the rest of the world — as a giant laboratory where ingenious new uses for drones are discovered all the time. Drones are being used to catch fish, wash windows, and sell homes 68 percent faster than houses without aerial images, according to MLS statistics.
Sales really took off in 2016 when DJI, the world’s largest manufacturer, released its Phantom 4, with smart computer vision and machine learning technology. It could avoid obstacles and intelligently track and photograph people, animals, or objects.
Since then, it’s become hard to even keep track of the ways drones have impacted society.
On Nov. 19, the Federal Aviation Administration (FAA) released the latest statistics on U.S. drones:
- 1,499,839 Drones Registered
- 1,079,610 Recreational Drones Registered (up from 878,000 in January 2018). Recreational users receive one identification number for all the drones they own.
- 416,210 Commercial Drones Registered (up from 122,000 commercial, public and other drones), which are individually registered.
- 158,554 Remote Pilots Certified
The FAA regulations for small unmanned aircraft (UAS) operations other than model aircraft – Part 107 of FAA regulations – cover a broad spectrum of commercial and government uses for drones weighing less than 55 pounds. It’s very important to be understand and follow the FAA rules. See Fact Sheet.
Another milestone for drones nationwide came in October, when U.S. Transportation Secretary Elaine Chao announced the FAA had awarded air carrier and operator certification to an UAS delivery company, UPS Flight Forward.
“This is a big step forward in safely integrating unmanned aircraft systems into our airspace, expanding access to healthcare and building on the success of the national UAS Integration Pilot Program to maintain American leadership in unmanned aviation,” Chao said.
Uses in Maine also are expanding. For example, the Certified Logging Professional program (CLP) purchased a drone with a grant from the Northeastern Loggers Association last January and CLP instructor Yves Levesque is now a certified UAS pilot. Several videos he’s shot are posted on CLP’s facebook page.
“We will now provide this service to CLPs and other interested organizations,” said Mike St. Peter, CLP director. “We also are looking forward to using the drone for training and education programs.”
Jason Irish of Irish Family Logging in Peru has been exploring ways to use his UAV for the past three years. See video.
“It’s paid for itself many times over,” Irish said. “It’s most valuable in counting bundles. It saves me a lot of time and a lot of walking. I can count bundles in about five minutes. Sometimes I get a call from the feller buncher about how he should get around some ledges. I can put the drone up and say go to the left to get around the ledges.”
The cost of UAVs varies widely. MFS, for example, now has seven drones. The first (and best) MFS drone cost about $2,500, Currier said, mid-level drones about $800 each, and entry-level drones, $400 each.
Soon the Agriculture, Conservation and Forestry Department (ACF) will have even more UAS. On Oct. 31, the Maine Bureau of Parks and Lands (BPL), Maine Natural Areas Program and Maine Forest Service were awarded a $10, 792 grant from the Maine Outdoor Heritage Fund to support deployment of drones for natural resource monitoring and enforcement. ACF intends to purchase up to 15 drones, FAA-sponsored training, and software to store and process drone images.
“Drones have great potential to increase our efficiency of monitoring forests, wetlands, and waters, and they can also be a really useful tool for highlighting Maine’s outstanding recreational resources.” said BPL Director Andy Cutko. “We’re thrilled to have MOHF support to help us adapt to this emerging technology.”
Research also is emerging that illustrates the value of UAS in New England’s forests. Benjamin T. Fraser and Russell G. Congalton, of the N.H. Department of Natural Resources and Environment, reported their research in the January 2019 issue of Forests.
“Our results demonstrated the ability to comprehensively map nearly 400 hectares of forest area, using a UAS, in only a few weeks time,” they wrote. “They also showed the significant benefit that could be gained from deploying UAS to capture forest landscape composition.”
Another important way that drones are being used in forestry isn’t likely to be needed much in Maine, since our forests regenerate naturally, but it’s extremely important to forest restoration worldwide. Drones can plant trees.
In Myanmar, for example, a project is under way to restore a billion mangrove trees in an area the size of Rhode Island. Planting by hand takes time, money and lots of workers, but two operators working with 10 drones can, at least theoretically, plant 400,000 trees in a day by firing biodegradable pods with a germinated seed and nutrients into the ground.
A bit closer to home, the Nature Conservancy is using a drone to aid its reforestation efforts in northeast Minnesota and UAVs are being called “game-changers for wildlife population monitoring.”
“The drone corridor has transformed Central New York and the Mohawk Valley into a global leader of this next-generation technology, while diversifying New York’s economy,” Gov. Cuomo said.
Of course, new technology can also have a dark side. Drones have interfered with firefighting in forests out west, although there have been no “incursions” in Maine, according to MFS. A Pennsylvania man was indicted in September for allegedly using a drone to drop explosives near his ex-girlfriend’s apartment. A drone operated by a youngster hovered over Fenway Park last spring, putting Red Sox players and fans on edge.
In 2017, the U.S. Army banned soldiers from using any unmanned aircraft manufactured by DJI, alleging the Chinese company shared critical infrastructure and law enforcement data with the Chinese government. Last May, the Homeland Security Department warned companies their data could be at risk if they use DJI drones. In October, the U.S. Interior Department, which has more than 800 drones, announced it would ground all its drones manufactured in China or containing Chinese-made parts, pending a review of the agency’s growing unmanned aircraft program.
Walker Day, who grew up in Lovell, began flying drones as a forestry student at the University of Maine, where he graduated in 2017. Thanks to a partnership formed between Seven Islands Land Co. and the Barbara Wheatland Geospatial Analysis Laboratory, he was awarded the first applied forest technology internship.
The Wheatland Geospatial Lab not only has specialized equipment, including a $30,000 UAV, the staff also has a great deal of experience.
“They’re the go-to guys,” Day said. “They know everything about this stuff.”
Now Day is a forester for Seven Islands in Rangeley and also chairs MFPC’s Drone Committee. Day uses a DJI Phantom 4 pro, owned by the Rangeley Lakes Heritage Trust, to monitor the trust’s forestland.
“You can tell hardwood, softwood easily,” Day said. “You can pick out your dead trees. We use it sometimes if we have areas with a lot of blowdowns. A few years ago we had a huge windstorm that came through and we thought we had a lot of blowdowns there. So it’s an easy way find out that we need to go in and salvage those.”
At first, everybody worries that a UAV will be hard to pilot, Day said, but they’re easy to fly and hard to lose.
“There’s a button on the remote controller and before you take off it updates the home point,” Day said. “So if you lose connection with the remote controller, once it gets to 15 percent battery life, it will automatically fly itself back and land.”
The appeal of UAS in forestry is “pretty obvious,” said Tony Guay, remote sensing specialist at Wheatland Geospatial Lab. “It’s the ability to take a pretty high-tech piece of equipment, that’s very mobile and easy to carry, and deploy it on a job site for evaluating a stand for harvest, for example, or doing post-harvest site inspection.”
David Sandilands, Wheatland Geospatial Lab’s aerial survey pilot and remote sensing technician, added, “It also adds a layer of safety where it can be deployed from the side of the road. The forester parks next to the stand and he or she can look over the area, fly over the area and inspect it without having to walk out into the woods where it’s easy to fall or trip.”
The Wheatland Geospatial Lab team also provides a service that’s valuable to mills. Historically, mill workers have “eyeballed” a chip pile, but estimating the size of the chip or log pile with a UAS is more accurate, safer, and can be completed in about 15 minutes. It doesn’t interrupt production because the pilot sets up on the edge of the mill property.
“These piles get wide and spread out and chips make strange shapes up top and you can’t account for that when you can’t see it,” Guay said. “So we started working with Verso and a couple of other mills where we would fly the UAVs over these piles. We give them cubic yards or cubic meters or cubic feet and they can see month to month the percentage of change. It’s very critical for them to have an accurate accounting of what’s out there.”
However, UAS do have limits. They’re only allowed fly 400 feet above the ground and generally aren’t equipped to fly in below-freezing temperatures, Day said, but he’s found a model that can fly at about five degrees because it has an insulated compartment for lithium batteries.
“The biggest hindrance and roadblock for us right now is the rule is that you can’t fly beyond visual line of sight,” Day said. “You have to be able to see the aircraft the whole time you’re flying it with your naked eye, unaided by binoculars or anything.”
FAA waivers to that rule are possible, he said, but rare.
Allison Kanoti, Maine state entomologist, also sees limitations related to battery life, flight distance, and processing power.
“I see them as most helpful at this stage in the game in more intensive survey activities, such as mapping small areas of browntail moth damage; following up on data collected from fixed-wing aircraft; getting a closer look at upper canopy areas,” Kanoti said. “They are also potentially helpful in tracking changes at particular areas, such as the hemlock impact plots we have in southern Maine, and in timing more resource-intense flights. For instance, we used a UAV to look at development of late-summer feeding damage ahead of scheduling flights with the more expensive fixed-wing aircraft flights.”
Another limitation is that the drone’s view may be blocked by the tree canopy.
“In a forest environment these photo-based techniques see what the camera sees,” Sandilands said. “So when you’ve got a closed-canopy forest you’re not going to see the ground, unless it’s post-harvest.”
There is, however, another tool that can penetrate dense tree canopy — Light Detection and Ranging (LIDAR), which now is becoming a more useful tool in Maine, Guay said, since data is available for much of the state.
Laser pulses are fired at the trees below and the time it takes for wavelengths to bounce back is used to create a 3D picture of what lies beneath. The data is combined with information from satellites to give an accurate “fix” of the UAV position. LIDAR can record information starting from the top of the canopy to the ground, which is highly valuable for understanding forest structure and shape of the trees.
In Scotland, for example, UAVs equipped with LIDAR are being used to build up an accurate map of the health of the forest floor and help protect native Scottish plants threatened by invasive species.
UAVs can also produce an orthophoto mosaic, Guay said, “which essentially is taking a photo and correcting it so the features that are in the photograph are in their true map position. So you’re taking a photo or set of photos and turning them into a map.”
Another application that’s important to Maine’s forest industry, where workers are often in remote locations, is search and rescue. A recent report by DJI noted stories in English-language news publications about lives saved that were saved when drones were used in search and rescue operations.
“Increasingly, UAS are proven to be essential tools for a wide range of lifesaving missions around the world,” said Dr. Robert Bowie of Down East Emergency Medical Institute (DEEMI), a nonprofit based in Orono.
In 2015, DEEMI became the first civilian search and rescue organization to receive FAA permission to use drones. They’ve proven their value in search and rescue, he added, by helping find people in places helicopters and fixed-wing aircraft can’t reach.
UAS with heat sensors can spot lost or injured people and deliver precision location information, Bowie said. They can even send information about the lost person’s medical status so that rescuers can bring the right treatment. They also can deliver supplies, including cell phones.
“We have a duty to use every tool we have at our disposal to help find, assess and intervene on behalf of the lost or injured patient,” Bowie said. “This includes UAS technology with imaging and sensor platforms to help find them faster and more reliably.”
Under Maine law, the commissioner of the Maine Department of Inland Fisheries and Wildlife (IFW) has the authority “to take reasonable steps to ensure the safe and timely recovery” of lost or missing persons.
IFW doesn’t own any UAVs, Col. Dan Scott said, because they are too expensive, especially to deploy across the state; limited by dense tree canopy, and can be borrowed (along with UAV pilots) from other law enforcement agencies, such as the Maine State Police, Maine Forest Service or local search and rescue groups. The state police, for example, used drones a total of 41 times in 2018, according to the Maine Criminal Justice Academy annual report on UAVs.
“On rare occasions, other agencies have assisted us with a drone in a search and rescue,” Mark Latti, IFW communication director, said in an email, “but Major (Chris) Cloutier said that we have found their use in search and rescue operations ‘extremely limited.’”
Lt. Kevin Adam, search and rescue coordinator for the Warden Service, says drones are most useful in searches around open water and open land and they also “have to be very careful how we deploy them because we might have helicopters and fixed wing airplanes around.”
The fact that UAS have to be in sight of the operator does limit their effectiveness, including the ability to drop supplies to lost persons, Adam said. “That’s at the most 1,500 feet,” he said, “so we could get people there (to help) quickly.”
“They’re certainly a tool, though, in search and rescue,” Adam said. “I could see how you could use them, for instance, in a scenario like the other night with that rescue on the Penobscot River (in Old Town, Nov. 11). You could have used a drone to maybe drop ropes.”
Bryan Courtois is president of Pine Tree Search, education director for the Maine Association for Search and Rescue (MASAR) and a certified UAS pilot. He agrees that “drones can be effective in the right conditions. Large open areas such as fields, open water, thin ice, swamps, etc. would be good candidates. Areas with tree cover would not be a good use of the drone. ”
The Maine Warden Service has called on Maine All Terrain Search and Rescue (MATSAR) and the York County Emergency Management Agency (YCEMA) to deploy UAS, Courtois said. The YCEMA has several drones, including two with thermal imaging cameras.
“Another good use for the drone would be to look at areas that would be potentially dangerous for people such as fast-moving water, chemical spills etc.,” Courtois said. “The drone can also be used to get an overhead view of an area such as a climbing accident, which would allow the (search and rescue) command to see the area without being in harm’s way.”
As Ranger Jeff Currier emphasized, people across the state are discovering ways that UAS can make a difference in Maine’s forests.
Remember Currier’s video of the forest fire caused by lightning? Because Currier had a UAS, he directed rangers to the exact GPS coordinate of the fire. An engine with 1,000 gallons of water was brought to a nearby road and rangers strung out 1,500 feet of hose. In an hour, the fire was out.
“We are just scratching the surface with the very most rudimentary uses of unmanned aerial systems and there are tons and tons of resources out there that are going to help us fine-tune it,” Currier said. “I think we’re going to show people very quickly that we can save time and money and put them to use to do good.”