MOUNT VERNON — Although this nation is one comprised of immigrants, in terms of plant life, not all immigrants are welcome. Garlic mustard, a plant brought to this continent from Europe, is now reaching the point where it is a threat to the natural biodiversity of the region, according to Kim Marshall, director of the Knox County Park District.
“Garlic mustard was actually introduced into the country by Europeans,” said Marshall. “It is edible. It is an aggressive, invasive plant,” she said.
According the Ohio Department of Natural Resources, the plant was first recorded in North America in Long Island, N.Y., in 1868. Garlic mustard can be easily identified by rubbing the leaf or stem of the plant together and then smelling the pulp; if there is a garlic smell, the plant is garlic mustard.
“There’ve been a lot of plants brought into Ohio and into the U.S. that are pretty benign,” said Marshall, “but ... garlic mustard is definitely one of the most invasive plants that we’ve encountered.”
Because the plant is so aggressive, it chokes out other native plants, which affects local biodiversity.
“It really does impact forest biodiversity,” said Marshall.
Other life forms depend on the diversity of local forests and woodlands, said Marshall, so these other life forms are affected when garlic mustard begins to invade.
“You never want to take a cog out of that biodiversity wheel,” she said. “We want our woodlots to be as ecologically stable as possible.”
Garlic mustard is especially hard to eliminate once it has taken hold in a location. Marshall said one plant can produce up to 600 seeds, and the seeds can lay on the ground for several years before germinating. The only way to completely eliminate the plant is to completely uproot it every year for a period of six or seven years.
“It’s very labor-intensive to try to manage or control this plant once it’s in your woodlot,” said Marshall.
Because garlic mustard is edible, there is an annual event held at the Patapsco State Park in Maryland called the Garlic Mustard Challenge, which is basically a cooking competition for recipes that use garlic mustard.
Doug McLarnan, operations manager for the Knox County Parks District, said that if his department had a full-time employee who worked every day throughout the year, Wolf Run Park would still face the problem of invasive plant species, such as garlic mustard, multiflora rose and autumn olive. Also, said McLarnan, the threat of the emerald ash borer could potentially add to the threat of invasive plant species.
Because 10 percent of the forests in Knox County are comprised of ash trees, if these trees are affected by the emerald ash borer and eventually die, it would create more edge space around forests, where garlic mustard and multiflora rose thrive.
Currently, the emerald ash borer has not affected Knox County, but it has been reported in nearby Delaware County and there are traps in several locations in Knox County — including Wolf Run Park — to try to prevent the spread of the insect.
