ANDERSON — On a golf cart ride through some of Anderson’s natural trails, Greg Spencer is on the lookout for some of the state’s famous wildlife.
A tall black vulture sits stooped over in a field. A brown ground squirrel rushes across the path and up a nearby oak tree. A hawk circles, searching overhead.
But more and more, as Spencer, the city’s tree commission liaison, scans the woods, he sees just one thing: Asian bush honeysuckle.
“It’s a scourge, it really is just a scourge,” Spencer says of the tight brown bushes stretching up to 15 feet in the air that have taken over massive swaths of the city’s protected woodlands.
“You look into the woods, used to you could see all the way back,” he said. “Now, you look and you can’t see more than two feet, and it’s all honeysuckle. You get so much honeysuckle and that’s all you can have.”
What started as an ornamental filler for landscaping, with attractive red berries and slick green leaves, has quickly spread out of control across much of the Midwest, particularly in Indiana’s northern and central regions.
The Asian bush honeysuckle is one of what’s known as a non-native invasive species, a plant or animal that can outperform and outgrow species that have traditionally lived in an area, often to dire consequences for native dwellers.
Though honeysuckle can be a beautiful plant, Spencer said, because it grows so high and so fast, it chokes out other plants. The high, dense branches block sun and rain from falling to the woodland floor, leaving only dirt underneath.
“Then it’s just a monoculture with no natural diversity,” Spencer said. “Once all the old growth trees die, there’s nothing left that can grow.”
It’s not just plants that take the damage; animals that rely on native berries and seeds can be forced out of an area if their preferred food is unavailable.
And once a species takes hold, the invasion only gets worse.
The Indiana Department of Natural Resources shows honeysuckle, which was first planted to prevent erosion and quickly spread, has continued to infect new areas each year spreading from the northeastern areas of the country farther west and south.
Not just one species
But prodigious as the honeysuckle might be, it’s not the only plant threatening the state’s delicate natural homeostasis.
Earlier this year, the DNR urged landscapers and homeowners to stop planting ornamental pear trees, most commonly known as Bradford pears, because they are beginning to spread out of control.
“Over time, different varieties of pear have cross-pollinated in our urban areas, allowing them to rapidly spread into our natural resources,” said Megan Abraham, director of the DNR Division of Entomology & Plant Pathology.
Cultivated forms of this invasive species are scientifically known as Pyrus calleryana or Callery pear tree. Commonly available ornamental pear cultivars include: Bradford, New Bradford, Cleveland select, autumn blaze, Aristocrat, capitol and Chanticleer. All of those should be avoided, DNR officials say.
Another plant that’s especially damaging the state’s wetlands is reed canary grass, a tall flat-leafed grass.
It is another species that was originally planted as a way to mitigate erosion because of its deep and creeping rhizomes, but it quickly grew out of control and has created monocultures in many of the state’s low-lying wetlands.
Fighting back
Ridding an area of an invasive plant species takes a lot more than just simply spraying a pesticide or clear-cutting the undesirable plant once or twice a year, said Kim Kaplan, chief of special projects with the agriculture research division of the USDA.
Instead, a landowner will have to inspect their land inch by inch several times throughout the growing season in search of the pest. And different species of plants can require different mitigation techniques.
Spencer, who works with the city of Anderson to control protected wildlands, says many private landowners don’t have the manpower or finances to fight a massive invasion.
“The point is you can’t go in one time and just do it," he said. "You have to be aggressive and clear it constantly. And even if you think it’s gone, it will probably crop up again — it’s an ongoing thing. And a lot of people just can’t keep up with that.”
Once the invasive plant is destroyed, it's important to plant a native species in its place.
The Department of Agriculture maintains a database down to the county level of species that have traditionally lived in an area.
Spence and Kaplan encouraged landscapers, gardeners and landowners to visit the site at plants.usda.gov when they are looking for something to plant.
“Usually, there is something just as beautiful or just as effective as the invasive species that people can plant,” Spencer said. “All they have to do is look.”