A tree is a tree, right? You just find one that you like, plant it and enjoy it. Well, not exactly. There are actually invasive species of trees that damage the ecosystem by taking resources from native plants — and this is true here in Indiana.
Each region will have different trees that evolved to be in balance with the other plants and animals of that area. And sometimes just one single species from another ecosystem can do incredible damage. Nature magazine, for example, calls kudzu “The invasive vine that ate the South.”
Banning of invasive plants in Indiana
In 2018, the State of Indiana passed a law, known as the Terrestrial Plant Rule, that banned 44 plants as invasive. The law went into effect in 2019. According to the state’s website, “This rule makes it illegal to sell, gift, barter, exchange, distribute, transport, or introduce these plants in the State of Indiana.”
These 44 plants were chosen by the Indiana Invasive Species Council, formed by the state government, after years of research into all the plants that were present, where they are native to, and what impact they were having. The invasive species were mostly introduced by the “horticulture industry,” meaning gardening and landscaping, and the ones chosen have become harmful and often difficult to manage after they spread from their original plantings into the wild.
Trees to watch out for in Indiana
On that list of 44 invasive plants, there are a number of shrubs, vines, weeds, grasses, herbs and trees. Much of the list is inhabited by vines and shrubs. If you are curious what they all are, click here for the full list. But since we are discussing invasive trees, here are the three trees that are listed among the 44 banned plants.
- Amur cork tree: As the name suggests, the amur cork tree has corky wood. The trunk is short, but it can grow up to 45 feet tall, because the branches grow far beyond the trunk. The tree comes from China and Japan and was introduced as an ornamental tree. They are invasive in that they will outgrow their plantings and displace hardwood trees in suburban and urban areas.
- Black alder: The black alder has a lot of close relatives in the birch family in the Midwest but is itself from Europe. It is larger than its American cousins; however, growing to 50 feet, and will replace them in the areas they both inhabit. Black alders form single-species colonies that suppress all other plants and change the soil conditions in ways that have unpredictable impacts.
- Tree of heaven: This native-Chinese tree was brought over as an ornamental tree, but quickly became a problem. It spreads chemicals that suppress the growth of all other plants around it, and cutting it down only triggers an aggressive growth reaction, where the roots grow into new trees. The tree of heaven has heart shaped leaves and smooth bark. It grows quickly and can survive in even the poorest soil.
Fighting invasive plants
As a landscaping company, Anthony’s takes seriously our responsibility to ethically provide the best plants, not only for you but for the whole area. We don’t want to provide a plant that looks great if it ends up harming the region’s ecosystem. Thankfully, there are great native alternatives to all the invasive species that were introduced in Indiana, and they look just as good and won’t harm our ecosystem.
With that in mind, we report any invasive species we are aware of and eliminate them where appropriate. We also, of course, do not buy, sell or plant any of these species on the properties we manage.
If you see one of these three trees listed above, or any of the other 41 species on Indiana’s invasive species list, please report them at 1-866 NO EXOTIC (1-866-663-9684). It will be a constant effort from everyone to get some of these problem plants under control and out of the ecosystem.
If you are in the Bloomington, Indiana, area, give us a call at (812) 345-5694 if you have any questions about invasive species or what some good native alternatives might be.