DULUTH -- The annual search for rare plants across Wisconsin has turned up a meat-eating plant in Ashland County that hasn’t been seen in the state in 45 years.
The English sundew (Drosera anglica), a carnivorous plant that traps and then absorbs its prey, was found in a bog in Ashland County last summer — the first time it’s been confirmed in Wisconsin since 1975.
It was first found by Don and Judy Evans, volunteers for the Wisconsin Department of Natural Resources Rare Plant Monitoring Program. When DNR botanists saw the rare finding, they sent Northland College Professor Sarah Johnson out to confirm it.
“We weren’t sure if it was English sundew, which is very rare, or another sundew, the linear, which hadn’t been documented at all since 1832,” said Johnson, who canoed to the site with two of her botany students from Northland. “It turned out to be English sundew, but it’s still a pretty big find.”
That single population of several individual plants remains the only one known in the state. The plant grows in wetlands like bogs and fens and can also be found on Isle Royale, Johnson said. Minnesota DNR botanists note it also exists in some northern Minnesota fens stretching from the Duluth area to about Lake of the Woods.
The English sundew attracts insects by secreting a smelly, sticky substance from its hair-like tentacles. When the insect lands, the plant secretes even more of the stuff and essentially drowns the insect.
“What’s really cool is that the plant can actually move its tentacles to slowly, over several hours, close in around the insect and help in the digestion,’’ Johnson said.
The English sundew is one of about 15 carnivorous plants known in Wisconsin. A more common species, the pitcher plant, uses vase-shaped flowers to attract and drown insects and even some small amphibians. Plants use insects, or meat, to supplement the nutrients they take up through their roots for photosynthesis.
“It’s sort of like people popping vitamin pills to supplement our nutrients,’’ Johnson said. “These plants grow in really nitrogen-poor environments, so they use the insects to supplement those nutrients that are lacking.”
Wisconsin has 2,366 native plant species and 344 of them — nearly 15% — are considered rare, meaning they are listed as endangered, threatened or of special concern. Sixty trained volunteers for the rare plant program fanned out across the state and turned in over 250 reports of rare plants they found last summer, including 59 populations in areas of Wisconsin where they have not been documented before.
The program, underway since 2013, recently posted its 2020 annual report at wiatri.net/inventory/rareplants/volunteer/newsletters.
“This is the most productive year we’ve ever had from the standpoint of volunteers finding rare plants in new locations,” Kevin Doyle, a DNR Natural Heritage Conservation botanist who coordinates the program, said in a statement. “These new discoveries are very exciting. They help increase our understanding of the number and locations of rare plant species so we can better monitor and protect them.”
The bad news is that volunteers didn’t find 63 previously documented plant populations. Some have likely disappeared only temporarily as many lakes, including Superior and Michigan, experience their highest water levels in decades and have submerged shoreline vegetation.