Armed with shovels, shears and a lot of enthusiasm, students in the Master of Environment and Sustainability (MES) program took part in a ‘Buckthorn Bust’ earlier this week.
The bust happened along the forested area of the Thames River behind the practice fields across from the FIMS/Nursing building on Lambton Drive, in collaboration with Landscape Services and Western Sustainability, as a project within the unit’s ‘Campus as a Living Lab’ initiative.
Western campus offers outdoor classroom
Students worked together pulling and digging out buckthorn shrubs of a small diameter, flagging larger ones, which were removed with chainsaws by a Landscape Services crew.
This past September, the students conducted ecological sampling of buckthorn in the area to prioritize a location for its removal. They took that data back to the classroom and analyzed it spatially to know where to target their efforts.
“We went in exactly where the data was showing there were high levels of buckthorn from our sampling,” said professor Paul Mensink, director of the MES program, adding that the project provides an opportunity for learning, with practical applications.
“It allows us to take the classroom outside, with the students collecting all the data and then taking action on it by removing the plants they’ve found earlier,” Mensink said.
MES students took part in a “Buckthorn Bust,” Wednesday, Oct. 25, 2023. Above: Josiah Esau, Aaron Mostbacher and Will Franklyn. Below: Sam Sears and Lela Burt.
Data collected at Western suggests that on average, 20 per cent of the forested area around the river on campus is covered in buckthorn, and up to 90 per cent in some areas.
What is buckthorn and why is it harmful?
The common buckthorn (Rhamnus cathartica) is an invasive species introduced from Europe in the early 1900s that has now spread throughout North America. It is harming biodiversity by preventing plant growth, decreasing soil quality and negatively impacting wildlife.
The woody shrub can grow to the height of small trees. It produces black berries in the summer that remain until mid-winter.
Mike Lunau, manager of Landscape Services, calls the berries “junk food” for the birds.
“It gives them a burst of energy, but buckthorn berries don’t support wildlife as well as berries from native plants,” he said.
The seeds of the berries move through their digestive tracts fairly quickly, with their excrement helping the buckhorn to spread. With the branches of the shrub running close to the ground, birds are more vulnerable to predators.
The shrubs’ leaves are rich in nitrogen, which is released into the surrounding soil when the leaves fall to the ground and degrade. Many native plants can’t tolerate the higher nitrogen levels in the soil around the common buckthorn.
Lunau noted there will be a two- to three-year lag before native plants will be planted to replace the removed buckthorn.
“The berries exist in the soil seed bank already,” he said. We’ll do successive removals to flush that growth. Once that’s knocked out, we will look at a replanting program.”
Mensink said the ongoing collaboration will continue to foster learning year after year.
“Our plan is to keep coming back every year, hammering at this area, and also measuring how the buckthorn is going down over time, with the students accessing data sets from previous years and analyzing it. It’s all part of their learning process. Many MES students go on to internships and careers that involve invasive species management, where they can use this practical knowledge.”
Jessica Cordes, engagement coordinator for Western Sustainability, said the buckthorn bust is “creating tangible change on campus,” which is one of the positive, ongoing outcomes of the overall ‘Campus as a Living Lab’ initiative.
“Students learn from the data they analyze in class and then experience hands-on learning by actually taking it out, having that rewarding feeling of making that physical change. This is something we can build on, not only with the living lab program, but with one-off events. We’ve made such a big dent in the forest, and we can keep expanding on that,” she said.