City hall is encouraging residents to watch for purple loosestrife, leafy spurge, bindweed or Dutch Elm Disease, invasive species that can damage and kill other native plants.
Purple loosestrife is a wetland invasive species that has taken over the river systems in Eastern Canada. While it looks beautiful, it is extremely aggressive and can wipe out cattails and other native flora.
Purple loosestrife is native to Europe and Asia and was brought to North America in the early 19th century. It was likely introduced when its seeds were included in soil used as ballast in European sailing ships and discarded in North America.
Sarah Regent, parks gardener for the City of Moose Jaw, explained that purple loosestrife grows and thrives along bodies of water, including near rivers and creeks.
“Unfortunately, it is a hard one to control because it is semi-aquatic, so you can’t spray for it (because it would harm other plant and animal life). But we do monitor for it, and we do go in in the summer and we will hand pull it out and take it to the dump,” she said.
Sometimes crews learn about purple loosestrife infestations on private property, such as on rural land or in Wakamow Valley, so they will notify those people how to mitigate its spread.
City hall does not quantify the amount it finds since it doesn’t survey how many square metres of land contain the plant, said Regent.
“We do know we have patches, and it seems to flare up in some areas, and in other areas, it’s quieted down,” she continued. “So, it’s hard to say year to year, but we have seen some progress definitely (in eliminating it) since we started the pull-out programs a couple of years ago.”
City crews were aggressive in removing purple loosestrife from Spring Creek a few years ago, with that area still free of that invasive weed, Regent added. This year, though, the city has had troubles in Sunningdale and near the Moose Jaw River along the Manitoba Expressway.
If residents see purple loosestrife on their property, they should remove it and take it to the landfill. If they see it on city property or elsewhere, they should report it to city hall — preferably through the app — and submit pictures and the location.
City hall has not discovered any new invasive species growing but is working to contain weeds such as leafy spurge or bindweed, Regent said. City crews can spray for these perennial plants, which usually occurs in the fall when the herbicides can better kill them.
Crews also mow leafy spurge to keep it in check.
There are some patches of those two weeds around the city, but they are usually found on the outskirts since they’re more of an agricultural problem, said Regent.
Meanwhile, it’s been “a pretty standard year” for Dutch Elm Disease, with city hall waiting for the results of a survey that crews conducted of the trees. Crews will conduct a second survey in August to ensure they found all infected trees since the disease can manifest later in the year.
“We are removing anything that we find. So if people see orange Xs on trees around the city and the tree is looking not very good, it will have Dutch Elm Disease,” Regent said.
The Dutch Elm beetle carries the disease and spreads it by flying and landing on trees, she continued. That is why there is a pruning ban from April 1 to Aug. 31; the smell of cut Dutch Elm branches attracts the pests.
Regent reiterated that people should submit pictures through the app if concerned about sick-looking trees — or other nature-related issues.
