Stopping the Sale of Invasive Plants in Indiana – and How You Can Help!

By Ellen Jacquart 
It started as a conversation between land managers. “I’m at the edge of the forest, spraying the purple wintercreeper that’s taking over the place, and I can see the neighbor actually planting this stuff in his yard!.” We saw the same thing with privet, Japanese barberry, Asian bush honeysuckle, and many other species – land managers killing these invasive plants, and well-intentioned, but uninformed, landowners continuing to plant them. The insanity of this led us to form a group in 2000, the Invasive Plant Species Assessment Working Group (IPSAWG), that brought together everyone with an economic interest in plants – those who sold them, designed with them, planted them, or killed them for a living. We came to the table with very different perspectives, but a shared agreement that there should be a way to measure how invasive a plant species is, and that truly invasive plants should not be bought, sold, or planted in Indiana.
For six years we met. We developed an assessment tool with a set of multiple choice questions and point values for each answer. Add up the points at the end, and the species would be ranked as high, medium, or low invasiveness, or caution (meaning there wasn’t enough information to complete the assessment, but there are indications of invasiveness). Simple, right? Not really. There was a lot of debating and discussing these ornamental plant species over the years, and though the process was long, we all learned a lot. 
What surprised me most was learning that many in the green industry (those who design with, grow, or sell plants for a living) already knew the troublemaker plants. There were plenty of businesses that not only designed and built landscaping, but maintained it. And planting species that took over the landscaping meant a lot more work to maintain it. With that shared understanding – species that can take over the landscaping may also take over our forests, prairies, and wetlands – we moved forward together.
After six years of meetings and assessments, we printed a brochure in 2006 on our results – “Making the Right Choice: Landscaping with Non-invasive Alternatives”. We handed out 100,000 of these brochures, and hoped that this would decrease the sale of invasive plants in Indiana.
It did not.
So in 2009, when the new Indiana Invasive Species Council (IISC) wondered what they should do about invasive plants, I told them we needed an official invasive plant list, and that what IPSAWG had developed was a good starting point. In 2010, the IISC created the Invasive Plant Advisory Committee, which I chair, to work on this list and other invasive plant projects. We spent a couple years updating the assessments, making county maps showing where each species is invading, and assessing new species. And then (drum roll, please) – we asked the IISC to make the invasive plant species that were ranked as ‘highly invasive’ illegal. No buying, selling, planting, or transport in Indiana. They agreed it was the right step to take, and asked the Department of Natural Resources – Division of Entomology and Plant Pathology (which holds authority over most invasive plant issues in Indiana) to examine taking this step.
They did, and they wrote a rule for all the plant species that ranked as ‘highly invasive’ (you can see all the species that ranked as high at would make them “restricted species” which would be illegal to “sell, offer or grow for sale, gift, barter, exchange, or distribute a species”, “transport or transfer a species” or “introduce a species”. That covers pretty much all the bases! For a few species that are not yet well established in the state, there is also a “prohibited species” category, which mean that the species may not even be possessed in the state.
That rule is now moving slowly through the rule-making process. It must first get through the governor’s “Regulatory Moratorium Committee”, which decides which rules may go forward. It is unclear whether the rule will get past this first hurdle. If it gets through that committee, it then goes to the Natural Resources Commission, the rule-making body for the Department of Natural Resources, for preliminary adoption. If it gets through the Regulatory Moratorium Committee, it would be heard at the September 20 meeting of the Natural Resources Commission. We expect a fair hearing at the NRC, and it is likely to be ‘preliminarily adopted’. This means that there would be an open public comment period on the rule. Here is How You Can Help: We need all the public comments we can get to demonstrate the level of concern about the continued sale of highly invasive plants. If you want to know when the comment period is open, and how to comment, send me an email at and I’ll add you to the email list to which I send updates on the rule. 
Once comments have been received, the DNR will evaluate and respond to comments, and bring it back to the NRC for final adoption, probably around 9 months after it goes up for preliminary adoption. If there is final adoption – that’s it. Highly invasive plants will be illegal to buy, sell, plant, or transport in Indiana. 
Does that make all problematic species in the state illegal to sell? No. A few highly invasive species, Callery pear and Norway maple, have already been removed from the rule to avoid a fight with green industry that could kill the rule. A few other species – like burning bush – came out as ‘medium’ in the invasive assessment, so don’t qualify to be in the rule. This is not a complete fix, but a giant step forward. There will be more species to assess in the future, but if this rule goes forward, it will be easier for land managers and landowners to address highly invasive plants and the problems they create.
Ellen Jacquart is the Director of Northern Indiana Stewardship for the Nature Conservancy in Indiana. She has worked in Indiana’s natural areas since 1987. She is also the Chair of the Indiana Invasive Plant Advisory Committee.