Search for the eradication techniques on the noxious liana kudzu (Pueraria lobata (Willd.) Ohwi) in consideration of cut-slope vegetation recovery

Kudzu (Pueraria lobata) is native to Japan and one of most noxious woody vine species causing adverse effects on ecosystems due to its strong reproductive ability. Its eradication from urban-rural landscape, especially revegetated areas is urgent. The ecological effects of five successive treatments (non-treatment, herbicide imazapyr, digging, biannual cutting, and shading) on the coverage of kudzu and composition of cut-slope vegetation were assessed for three years between June and December each year. Among the five treatments, a shading treatment was conducted from the second-year experiment on behalf of an annual cutting. Eradication of kudzu was rapidly achieved after implementation of digging and shading treatments. Especially, in the case of digging method, there is no need for continuous treatment after the initial one. Furthermore, although vegetation cover, number of species, and their life cycle composition diversity on cut-slopes increased in digging treatments, these recovery after shading treatment were not found throughout the experimental periods possibly due to the short non-shading treatments. Little eradication effects of other treatments on kudzu were found. From these results, we suggested that, among the treatments selected, the digging treatment, regardless of its high initial treatment costs is most effective to eradicate the noxious liana kudzu and taking into account recovery of vegetation on cut-slopes.