LANSING, Mich. (WILX) – It’s a fast-growing, troublesome invader that could cause damage to the roads and your home.
State officials are warning about high levels of Japanese knotweed here in Michigan. The invasive plant could break through concrete causing you some pretty costly damage.
“If a small piece dropped, it could become a new plant over time and it changes the environment,” according to Shika Singh of the Jackson, Lenawee, Washtenaw Cooperative Invasive Species Management Area. She’s an invasive species biologist.
“So, as you can see in some of the sites we visited, there’s not a lot of diversity there in the plant community,” Singh said, “It’s just a lot of Japanese knotweed.”
The invasive species is prohibited and it’s on the watch list for Michigan’s invasive species.
Singh said Japanese knotweed out-competes native plant species that are important to birds and pollinators. The knotweed smothers other plants causing native species, like insects and birds, to leave the area.
However, that’s not the only issue.
She said, “It’ll exploit any holes or cracks in the foundation of a building or by a cement wall or by a parking lot.”
“Crumbling infrastructure, damages, potholes. You can see raised edges as you drive in parking lots and or on roads.”
This type of knotweed, Singh said, also causes damage to your property. She said the horizontal underground stem is a major cause of issues because it is always looking for water.
“So, in the search for water, I’ve seen cases where the rhizome has actually made its way from outside into someone’s basement and that could be a very expensive problem.”
Herbicide is the best way to treat Japanese knotweed. Singh said mowing the plant only stimulates more growth. She said the best time to treat it is either at the end of summer or early fall.
According to the Michigan Department of Agriculture and Rural Development, you should not mow or compost Japanese knotweed.
Severe infestations will require repeated attacks throughout the year:
- Smothering: Spring
- Cutting: Throughout the summer
- Digging: Anytime, especially just before using the smothering technique
- Herbicide: Summer or early fall
If you believe you may have seen this plant, you should visit the Michigan Invasive Species Information Network (MISIN) where once registered, you can file your report.
Subscribe to our News 10 newsletter and YouTube page to receive the latest local news and weather. Looking to hire people, or grow your business through advertising? Gray Digital Media is your one-stop marketing solution. Learn more.
Copyright 2024 WILX. All rights reserved.