Japanese knotweed (Fallopia japonica) is an invasive species in Europe and North America; associated with increased soil erosion, loss of native plant diversity, and accelerated destruction of riverbanks. In Nova Scotia, there is growing interest in the management of Japanese knotweed, due to its negative impacts, and the ability of the species to occupy large areas. Between 2016 and 2018, experimentation evaluated: (i) integration of cutting and herbicide application, (ii) injections compared to spot applications of herbicides, and (iii) impact seasonal timing of herbicide application on knotweed stem regeneration. (i) Knotweed stem density was reduced to a similar degree regardless of if cutting was performed prior to herbicide application. (ii) Injections were not significantly different from spot sprays, both reduced knotweed stem density, but required two applications. (iii) Peak height and fall applications were both effective, group 4 herbicides performed best in the fall.
Assessment of Effective Management Strategies for Japanese Knotweed