Lane
By KADY LANE, guest columnist
A 2021 study estimated that invasive species cost North America $2 billion per year in the early 1960s to over $26 billion per year since 2010, according to the United States Department of Agriculture.
Globally, it is estimated that the economic cost of invasive species has been $1.288 trillion over the past 50 years.
The Indiana Terrestrial Plant Rule has designated 44 different plant species in Indiana as invasives. Invasive plants are defined as plants that are non-native to the area and because of their introduction to the area there is potential to cause harm to humans or the environment.
It is true that most non-native plants cause little harm, but others are blamed for destroying thousands of acres of natural plant communities in Indiana. They have been known to displace native plants, eliminate food and cover for wildlife, and threaten rare plant and animal species.
Plants topping Indiana’s list of most invasive plants include Japanese honeysuckle, Asian bush honeysuckle, purple loosestrife, crown vetch, wintercreeper and Japanese stiltgrass. I want to focus on Japanese stiltgrass for the remainder of this article.
Japanese stiltgrass (Microstegium vimineum) is a sprawling densely matted annual grass that grows from six inches up to three feet. There is a slightly silver stripe down the leaf blade that can help to identify this plant. Often you can find it bending over and rooting at nodes.
It has alternative leaf blades up to four inches long, and it is easy to spot this tall tan grass in the winter. It flourishes near stream sides, forest edges, ditches, damp fields and yards, and trail sides.
This plant is very shade tolerant and each plant can produce up to 1,000 seeds. These seeds can remain dormant in soil for up to three years and spread from place to place on hiker’s shoes and clothes as well as on logging equipment.
Management strategies include mowing before it can come to seed, and hand pulling. Make sure to clean tiny seeds off of shoes, clothes and pets if the plant has already gone to seed, which is generally in September.
Dense infestations of this plant can fuel fires. Prescribed burning is not recommended because it can actually promote the spread of existing infestations. If you want to treat with a late winter or early spring pre-emergent, the suggested time frame is late February through March.
Kady Lane has worked as an educator for many years, teaching science in grades seven to 12 as well as adult education for Indiana University-Purdue University Indianapolis. Her master’s degree is in environmental studies and her undergraduate is in human services and psychology. Lane is currently the Brown County Soil and Water Conservation District educator and can be contacted at [email protected].
