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Invasive Species: Don't get knotted (2 photos)

Japanese Knotweed 'a nightmare' says Invasive Species Centre officer

Feb. 27 through Mar. 3 marks National Invasive Species Awareness Week in the U.S.

At the same time, Sault Ste. Marie’s Invasive Species Centre will be holding its own awareness week for our area.

The Sault’s Invasive Species Centre’s staff fight against those species that have made their way here, and also have their eyes peeled on keeping even more unwelcome insects, fish, plants and trees out of our area’s precious ecosystem.

The public is invited to follow the Invasive Species Centre’s campaign on Facebook and Twitter (@InvSp) and to follow it through the week using the hashtag #InvSpWk

The theme of the week is ‘Protect What You Love.’

SooToday, with research provided by the Invasive Species Centre, will be highlighting a different form of invasive bug, vegetation or fish each day this week.

So far, we’ve taken a look at Oak Wilt (a disease which affects oak trees) and the Asian Long Horned Beetle

Add Japanese Knotweed, a large plant, to the list of concerning species.

Unlike Oak Wilt and the Asian Long Horned Beetle, which have so far been kept from the Sault and area, Japanese Knotweed is very much present, said Taylor Wright, Invasive Species Centre project manager.

“This plant grows, and it’s in Sault Ste. Marie,” Wright said, pointing to public property located on Queen Street East, in an area where many people walk their pets and located close to a municipal snow dump.

The area affected, Wright estimated, spans over 40 feet wide and the weed itself is 15 feet high in some places.

“It’s a woody shrub, the stem on it is hollow and a lot of people nickname it Japanese Bamboo.  It was brought over from Asia as an ornamental plant because it is absolutely gorgeous, in the fall it has a beautiful white flower and it’s very appealing.”

“(However) people started to realize it grows very quickly and competes with a lot of our native species, and later on we found out how destructive it can be to infrastructure.” 

How destructive?

“A lot of people have planted this next to their house as a hedge line and the root system is so strong and extensive it can actually break through the foundation in your home, so people have experienced it breaking through the concrete foundations of their house and growing into their basements,” Wright said.

Japanese Knotweed was brought over as an ornamental plant for gardens and a lot of people are still splitting it and giving it to friends and neighbours for their gardens, not realizing the major problems that will arise 10 years later.

“The root systems can grow down as deep as five metres (16 feet) and this plant can reproduce from fragmentation,” Wright said. 

“That means even if you try to dig it up, if you leave just a little bit of the root, it’ll sprout again.  It’s really hard to get rid of.  You’ve got to, essentially, bring in a backhoe, you have to remove the plant and you have to take all the soil to a contaminated soil site because it has all the root fragments.”

“Once you have this, it’s a nightmare,” Wright said.

The Invasive Species Centre has no authority to forbid a private citizen from planting of species such as Japanese Knotweed, and “there are very limited (governmental) resources available to manage invasive plants because it’s often a multi-year battle, and we’re also limited by law with the type of herbicides we can use,” Wright said.

“(But) we have seen some successful attempts at eradicating this plant, particularly in Thunder Bay.”

“It’s a tough battle, a lot of times gardeners and homeowners like the look of certain plants and they aren’t able to see the long term repercussions of introducing these species.”


Watch for it, stay away from trails where Japanese Knotweed is known to be, clean and remove mud, seeds and plant parts from clothing and pets after being out on the trails, don’t disturb soil and keep it natural (plant native plants only).

More information on the attractive but pesky Japanese Knotweed can be found online

SooToday will highlight another form of invasive species Thursday.



Darren Taylor

About the Author: Darren Taylor

Darren Taylor is a news reporter and photographer in Sault Ste Marie. He regularly covers community events, political announcements and numerous board meetings. With a background in broadcast journalism, Darren has worked in the media since 1996.
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