By Laurie Fagan, CBC News Ottawa, July 21, 2017
Conservation experts in Ottawa are waging war on Japanese knotweed, an aggressive, invasive plant species which has taken root in more than a dozen places on the city's shorelines. If it's not controlled, biologists warn the foreign plant — strong enough to break through walls and roads — will spread, displacing wildlife and crowding out native plant species in many areas.
"It grows so aggressively that it overpowers and overtakes shoreline areas where native vegetation would normally establish," said Rosario Castanon, who is co-ordinating the Rideau Valley Conservation Authority's efforts to control the weed.
http://www.cbc.ca/news/canada/ottawa/plants-invasive-japanese-knotweed-ottawa-1.4214989