Officials with the Bighorn National Forest are moving ahead with plans to apply herbicide to large areas of the forest by plane, helicopter, or drone beginning next year. The plans were met with both support and concern from government organizations, environmental groups, and ranchers who use U.S. Forest Service (USFS) lands.
Thad Berrett, a Rangeland Management Specialist with the USFS, said an aerial application aims to improve the reach of herbicides over a larger area than what can be done with the current ground-level approach.
"The aerial application [is] looking at the different options we have from drones to helicopters," he said. "The really hard to get to weed locations that are just hard to access or in rough terrain that you couldn't take an ATV on—those are the types of spots we'd consider going in with a drone."
Berrett says he can't recall herbicides having ever been aerially applied in the Bighorn National Forest previously, though they have been used at ground level for many years. A draft Environmental Impact Statement (EIS) lists 5,310 acres that would be treated for invasive plant species under Alternative 2, which is the Forest Service's proposed plan. 5,100 acres would be treated for Mountain Big Sagebrush.
The proposed herbicides target invasive species, which often grow along travel corridors and areas that are otherwise disturbed, such as those that are popular for recreation activities.
Aerial application can lessen the impacts that herbicides will have on ground crews in addition to saving time and money.
Some supporters of the USFS’s plans include ranchers who use the Bighorn National Forest.
"I am supportive of aerial application of herbicides," said Dan Rice, a Ten Sleep rancher who grazes cattle there. "The ability to do aerial application is an effective way to do management with herbicide on a broader scale. I also support it because of the additional use of our public lands through recreation. The opportunity for a larger and greater spread of invasive species is there."
Currently, herbicides are applied by ATV or by backpackers. The Forest Service has agreements with county Weed and Pest offices to do the actual application process. This includes Sheridan, Johnson, Big Horn, and Washakie counties, which are the four counties that are part of the Bighorn National Forest.
"There's just so much forest up there, there's so many acres up there to cover and be able to manage," Rice said. "Like with anything, a ranching operation or any business, it has to become more effective in the use of the dollars that are available."
The USFS’s plans have drawn some concern, including from the Bighorn Audubon Society. Rob Davidson is on the Bighorn Audubon's board of directors. He said they have concerns about what the impacts of herbicides will be on small bird and wildlife species.
"It doesn't seem like we have much problem making more deer and more elk," he said. "But we do have a real problem making more songbirds and more sage grouse."
Davidson said that these smaller birds, such as sage grouse, are dependent on sagebrush for their habitat. Some of the proposed herbicides target sagebrush, in part to allow for more grass growth.
"When we look across the West, how much sagebrush habitat that we've lost, and how many sage grouse are [in a] much more precarious situation, this is just a non-starter for us," he said.
Some of Davidson's other concerns focus on what he claims is the Forest Service’s lack of knowledge as to the numbers of birds in areas to be treated with herbicides. He’s also concerned that budget cuts have reduced the ability of the USFS and the Wyoming Game and Fish to adequately prepare and execute these plans.
Ideally, Davidson would like to have invasive plant species treated differently from how they currently are.
"No use of aerial [application of] herbicides on sagebrush or to the other native plants like larkspur," he stated. "Opening up the process of when they have to do the [prescribed] burning to a project level, which would basically revert back to the preferred alternative, which is going back to the mowing, burning. But it needs to be done better."
According to Berrett, the Forest Service has taken the concerns of the public into consideration and considers the costs to resources and the public.
"We've got a good team of folks with the Forest Service as well as the Wyoming Department of Environmental Quality, Game and Fish, [and] Department of Agriculture," he said. "If it comes to aerial application, we'll be thinking about the chemicals we're using, whether we need buffers around streams, whether we've got sensitive plants or animals. All those things people brought up as concerns, we're taking that into consideration and we’ll ensure that we're providing the right treatment with the least amount of negative impact and the best long-term positive impact."
The public comment period was from June through August of 2021. The Forest Service is currently reviewing comments and working on responses and how they will be addressed in the plans.
"We're working for a final environmental impact statement and the draft record of decision that will be coming back out to the public in January of 2022," Berrett said. "So that will be everybody's chance to see what it is that we're planning to do and how we analyze the effects and how we took the public comments and incorporated those into the document. At that time, anybody who commented before will have an opportunity to object if we didn’t address their concerns adequately in their view."
Following the second public comment period, the plans should be finalized in April with herbicide application possibly beginning by summer.
