Giant knotweed

Perennial shrub reaching 3 m. Introduced to Québec and invasive. Grows in forests.

There are 89 observations of Giant knotweed in Québec, mostly in Capitale-Nationale, Gaspésie–Îles-de-la-Madeleine and Estrie, and it has been reported in 10 of the 17 regions. They peak in May and June and become rare from November to April.