LAPORTE, Ind. – Invasive plant species are posing a threat to the nation’s forests, but the public can help stop the spread.

That was the message of A.J. Popovic, a specialist with the State of Indiana Cooperative Invasives Management organization, during his Feb. 27 speech at the annual meeting of the La Porte County Soil and Water Conservation District Board.

Unless the problem is fixed, “our kids won’t see our forests. Our grandchildren won’t see our forests,” he said.

According to USDA, fast-growing invasive plant species also pose a growing threat to yields by competing with crops for sunlight, water, space and other shared necessities, increasing the cost to farmers to control the spread.

Popovic said 25 percent of all plants in Indiana are invasive. He said many invasive plant species were brought to the nation from other countries in the 1700s and 1800s for landscaping, preventing soil erosion and for medicinal purposes.

Invasive plants such as burning bush and garlic mustard often spread because their seeds are taken and dropped birds while in flight. The result can be invasive plants taking root in forests and quickly multiplying until they choke out the native species.

He said the burning bush looks nice and harmless but the ability of the species to penetrate undisturbed forests has “done a lot of damage.”

Popovic said Asian bush honeysuckle, for example, can grow with such density that native plants and young trees below them don’t receive sufficient enough sunlight to survive.

“If you got infestation, your forest is at-risk because it does not have trees to replace the ones there currently,” he said.

Another invasive species, round leaved bittersweet, has vines that can wrap around trees and kill them by restricting the flow of nutrients. Tree of Heaven is another invasive plant species that spreads quickly from new growth emerging from their roots, which can grow 50 feet long in either direction.

Popovic said that species thrives in areas like former industrial sites like the old Studebaker plant on the south side of South Bend, where one Tree of Heaven plant reached 80 feet in height.

He said 85 percent of invasive species spread from landscaping while 14 percent of invasive plants migrate from agricultural areas.

Popovic also cited examples of what organizations like his have done to try to curb the spread of invasive plants.

He was directly involved several years ago with restoring the Lydick Bog property, where burning bush took over the entire back half of the 200-acre site acquired in 2017 by the Shirley Heinze Land Trust.

Popovic said the restoration involved taking out the burning bush and other invasive seed-producing plants. “We were able save that forest,” he said.

The Shirley Heinze Land Trust is dedicated to preserving and restoring natural areas throughout northwest Indiana and has about 4,000 permanent protected acres across Lake, Porter, LaPorte, St. Joseph, Marshall and Starke counties.

Popovic also talked about a trip he took to Boston before Thanksgiving where he discovered major infestation of invasive plants.

“Every single forest I saw was completely overrun with burning bush. It was a complete take over,” he said.

He said individuals can also do their part in the battle by educating themselves about invasive species so they can recognize and act against any that might be in their yards or landscaping arrangements.

Popovic said individuals should replace invasive species with native plants and manage the property correctly to prevent the emergence of invasive plants in the future. He said people should also report the presence of any invasive species and their location to the proper authorities.

USDA, through various departments like the Animal and Plant Health Inspection Service, works to prevent invasive plant and insect species from entering the U.S. and control their spread once established.

Other departments include the Agricultural Research Service, which conducts research on the biology, ecology and impacts of invasive plants and provides safe management strategies.

USDA’s Natural Resource Conservation Service and Farm Service Agency provide technical and financial assistance to landowners for invasive plant control.

According to USDA, invasive plants can also impact livestock by damaging the health of the plants they consume in pastures.

About 200 people attended the meeting and enjoyed a free dinner in the Community Building at the LaPorte County Fairgrounds.