Sometimes the most destructive species are also the most beautiful. Invasive species in Illinois include the spotted lanternfly with its vibrant red body, while the massive Burmese python has had a devastating impact on Florida’s Everglades. Now, there’s a non-native plant in Indiana that’s been long appreciated for its beauty, but its spread is growing out of control. It’s called the oriental bittersweet, a vine that grows eye-catching orange-and-red berries, and its once-beloved reputation is quickly degrading in the face of the takeover.
The oriental bittersweet is known by many names. It’s also been called the round-leaved bittersweet, the oriental staff vine, and the climbing spindle berry. First brought to the northeastern United States from eastern Asia in the 1860s, the plant was often bought, sold, and shared among homeowners in the Great Lakes region. Gardeners loved the thick vines, clustered orange berries, and plump round leaves, and it was a common ingredient in wreath-making. Few suspected that after 100 years, the curious vine would start wreaking havoc in national park forests.
Oriental bittersweet is destructive in several ways. The most devastating is how quickly it hogs sunlight. The leaves blanket forest canopies, while the vines spread from tree to tree, preventing native plants on the forest floor from getting adequate sunlight. Sometimes, its curtains grow so densely that it’s difficult to even identify the plant species underneath them. The oriental bittersweet hogs nutrients, as well. Vines can grow as thick as six inches across as they wind up tree trunks, sapping nutrients and water from the soil at the base of the tree and disrupting capillary action.
Why Indiana’s parks are suffering from an oriental bittersweet takeover
According to a 2016 report from the United States Department of Agriculture, the oriental bittersweet is prevalent in 11 U.S. states: Connecticut, Delaware, Indiana, Maryland, Massachusetts, New Hampshire, New Jersey, Ohio, Pennsylvania, Rhode Island, and West Virginia. While infestations are growing concerns in all 11 states, the plant’s widespread proliferation in Indiana’s state parks in particular, has bloomed in recent years. Hoosier park authorities have lately reported “massive” infestations, especially mentioning Brown County and Clifty Falls State Park…