Maya Porter reported this story on assignment from the Barre-Montpelier Times Argus. The Community News Service is a program in which University of Vermont students work with professional editors to provide content for local news outlets at no cost.
Intentionally or not, many species of plants and animals hitch a ride, set up camp in a new environment and, as far as people are concerned, get a little too comfortable. Invasive species are a big issue in Vermont, and the debates surrounding their management often center on another contentious issue — herbicides and pesticides.
In February this year legislators and regulators updated the Vermont Rule for Control of Pesticides. The revised rule came after a mandate from the Environmental Protection Agency in 2017 giving states until 2025 to match or exceed federal regulations enacted that year. The Vermont bill, which increased the regulation of pesticides, was unpopular with environmentalists who said it didn’t go far enough to limit the use of pesticides.
The management of invasive species is not simple, with different tactics deployed against the three main categories of the ecological interlopers: terrestrial plants, aquatic species and forest insects and pathogens that invade trees. Each is managed by a different government organization, sometimes multiple, and sometimes those organizations overlap.
Vermont Department of Forest, Parks and Recreation Invasive Plant Assistant Coordinator Lina Swislocki explained that for a species to be considered invasive, it must meet two criteria: It must have evolved somewhere else and cause harm to humans, the ecosystem or the economy.
Without the natural predators and competitors from their home environments, these newcomers can take over and wreak havoc. “When plants evolve in an ecosystem, they have predators and diseases and all these other entities that compete and help keep their growth in check,” Swislocki said. “When invasive plants arrive in a new ecosystem, they don’t have any of those, which is one of the ways they are able to grow so aggressively because there’s nothing to counterbalance those adaptations.”
Swislocki’s department is a part of the Forest Health program, a research program within the Parks department, and works on manual invasive plant removal and educating the public about invasive species prevention and management.
“We don’t have a ton of tools we can use to stop them from spreading really quickly, and chemicals are one of the few tools we have,” said Swislocki. “Chemicals get a really bad rep and for good reason — they are poison. The intention is to kill the plant, but sometimes that is the best option. We want to keep certain species out of certain areas, and chemicals are sometimes the best way to do that.”
The Vermont Natural Resources Council, a nonprofit environmental advocacy and research group, on the other hand takes a hard stance against the use of herbicides or pesticides for controlling invasive species.
“I would never want to use a chemical unless there was real ecological harm that is happening and the chemical is the only to respond to that — I don’t think we should just default to chemical application,” said Karina Dailey, restorative ecologist at the council.
Dailey often deals with invasive plants in her work removing dams from Vermont’s rivers. One of the biggest problems the plants pose for Dailey’s work is in sediment removal. If there are invasive species upstream of the sediment, then it must be handled carefully to prevent spreading invasive species’ seeds.
Many organizations with stakes in the dam removal projects support the use of chemicals, Dailey said, but she disagrees: “I think sometimes the risk of using chemicals outweighs the ecological benefits of the project itself.”
When it comes to invasive species, experts say prevention is key. “A lot of the invasive plants that we have in Vermont are so well established that we’re not going to be able to get rid of them, but theoretically we could prevent them from spreading to more places if we’re able to disrupt their reproduction,” said Swislocki.
“For people who are concerned about the spread of invasive plants, knowing what species they’re dealing with and how to disrupt the reproduction of that species is key.”
Dailey says the best way you can manage invasives on your own property is to avoid gardening with chemicals, pull up what you can manually and be mindful when bringing new soil onto your property of where it’s coming from.
“We’re all invasive on some level,” she said. “Is that a fight I want to fight all the time? No. I don’t think it’s a battle that we’re winning or that we need to win.”