Controlling Japanese Knotweed
Evidence shows that manual removal, digging it up or chopping the stalks, is not a viable long term solution. The species of Knotweed that the City of Pitt Meadows is dealing with does not ‘seed' like other invasive weeds. The combination of the deep root network and the fact that the smallest amount of the plant, less than 5 grams of material, can re-root making the eradication of the plant very difficult.
One consistent message that we are hearing from experts throughout the region is that organic chemical controls, such as vinegars, are not effective in controlling Japanese Knotweed. The use of specific chemicals seems to be the most effective, and the method we will be using in Pitt Meadows is the injection of the chemicals into the plant stalks. The City is proceeding with caution due to our Bylaws which limit the use of chemicals to control nuisance weeds. The method that the City deploys in dealing with the Japanese Knotweed and other Noxious Weeds is done in ways that ensure that the eradication is targeted and mitigates any impact on native plant species.
If you see Japanese Knotweed, or signs indicating the plants being treated, avoid contact and keep pets away. If there is contact with plants that have been treated and should any skin irritation occur, wash affected areas with soap and water.