When Sierra Vilmo looks back on her year of GreenCorps service at Cedar Creek Ecosystem Science Reserve, one image in particular stands out: looking out over an expanse of newly opened understory in the forest, then loading 13 large garbage bags full of invasive garlic mustard into a truck with a team of volunteers.
“It was really rewarding to see the tangible evidence of two hours of work,” she remembered. “And hearing all the volunteers talk about how cool it was to see the change after such a simple task — it brought me a lot of joy.”
In addition to leading volunteer and educational programs, Vilmo has spent the last year as a Minnesota GreenCorps member tackling another invasive species at Cedar Creek: the black locust. Valued for its excellent timber, as well as the tasty honey made from its flowers, the black locust was brought to Minnesota from Appalachia in the mid- to late 1800s. And, while it has done its part in its new home by helping stop erosion and by fixing nitrogen in the soil, the invasive tree is also choking out native plants.
At present, the most common way to rid the landscape of black locust is simply to pull out young trees. But this is not only slow going, it can be a Sisyphean effort, as the plant spreads through seeds that can stay viable up to 10 years, as well as through an expansive underground network of suckers. In collaboration with Anoka County Conservation District, Vilmo is testing two newer methods of eradication: girdling, or stripping off a ring of bark around the tree to cut off the flow of nutrients, and an herbicide treatment. So far, results show that girdling barely even slows the hardy trees down, but the herbicide is showing some promise.
Vilmo has tracked the progress of her efforts by mapping and measuring more than 500 trees in three sites near Fish Lake, risking swarms of biting insects and inch-long thorns. A good day at the office for her is a good day out in the woods, which was something she was missing in her original undergraduate major, pre-veterinary science.
“I loved science and I loved being out in nature, so I took some more ecology classes and ended up switching,” she explained. Having earned her bachelor’s from Minnesota State University Moorhead in ecology and evolutionary biology in 2022, Vilmo now gets the best of both worlds.
“We have been a host site for Minnesota GreenCorps members for a number of years, and each year it is a joy to see how the service members take ownership of their service plan,” says Kara Baldwin, education and community engagement coordinator at Cedar Creek. “Sierra’s passion and energy around land restoration, science, and the outdoors was a great fit. I am very impressed by her passion, perseverance, and creativity around the black locust project, and am grateful to have her as part of the Cedar Creek team this service term.”
Vilmo says she’s learned two things about conservation research during her time in the GreenCorps: first, that it rarely goes in a straight line, and second, that she can’t wait to do more of it.
“Research can be a kind of meandering process,” she said. “Things happen, and you can have a really tight plan and know exactly what you’re doing, but then one thing changes and you have to start from square one to figure things out again.”
But that hasn’t put Vilmo off at all. She’s now weighing her future options for graduate study and thinking hard about restoring and conserving wetlands in particular. Invasive species of the Upper Midwest had better watch their backs. –Tricia Cornell