Invasive plant species are becoming a major concern for Indiana’s environmental, ecological and economic sectors. Experts want to add more invasive species to the banned list of plants for lawns and gardens.
Dawn Slack, project manager at the Indiana Invasives Initiative, said they have requested more species be added to the Terrestrial Plant Rule.
“We do actually have about 10 species that we would like to add to the current terrestrial plant rule,” she said.
The current terrestrial plant rule has 44 invasive plant species on the prohibited list.
Adding more species to the list takes some time because the rule is going through a re-codification process. In 2021, the Department of Natural Resources (DNR) division of entomology and plant pathology proposed an amendment. In 2023, the DNR decided that all rules must be re-codified and during this process no rules could be amended.
“When we get the okay, then we hope that the rule making process will begin to add those new species to the current terrestrial plant rule,” Slack explained. “And those new species include Callery pear, burning bush, made in grass. we would like to add those to the terrestrial plant rule.”
The DNR says it is committed to ensuring invasive terrestrial species do not spread through the nursery industry.
Marty Benson, spokesperson at the DNR, said it is monitoring possible invasive species. “DNR is evaluating options to add new species of invasive terrestrial plants to the existing terrestrial plant rule that became effective in 2019,” he wrote to WFIU/WTIU News in an email.
How do species get onto the TPR list?
Plants that are non-native may cause harm to the economy, human health or the environment and are considered invasive. Assessment of a plant can take years, per the federal definition.
“If we say it's invasive, it is run through a very rigorous multi-year process, questionnaire and habitat assessment and all kinds of things to include even looking at its commercial value,” Slack said.
Experts constantly assess plants to determine if they're invasive. Based on the assessment, the Indiana Invasive Species Council has an official invasive plant list that is ranked.
Seventy-nine plants are ranked as highly invasive out of 128 on the official list. Only 44 that are ranked "high" are in the current TPR.
Even though some species are not on the state TPR list, community effort to remove and replace them with native plants is ongoing. Monroe County-Identify and Reduce Invasive Species (MC-IRIS) is a citizen coalition working to reduce the environmental and economic impact of invasive species.
MC-IRIS is providing 20 landowners up to $400 to reimburse the cost to remove Callery pear, Tree of Heaven or white mulberry. Landowners removing Callery pears can also get a replacement tree.