Inefficiency of cutting stems once during the vegetative growth of Fallopia spp.

Abstract : The management of some invasive plant species is difficult because species can exhibit high productivity despite control measures. Inefficient control methods may even produce unwanted side effects. We conducted an experimental study on Fallopia spp., a major invasive plant in Europe. We tested the effects of two different stem-cutting frequencies on the aboveground and belowground traits of several genotypes in a greenhouse experiment against control plants (no cuts). Plants receiving one cut per month for a total of 4 cuts experienced 30% mortality of the individuals, surviving plants had greatly reduced values of the measured traits, especially for biomass and height. In contrast, plants in the treatment group, consisting of a single cut in five months, were eventually able to compensate for the loss of aboveground parts despite reduced length and biomass of the rhizome. Our results indicate that minimal mechanical intervention has limited effects on Fallopia spp. During the vegetative season, managers can increase control efficacy through regular cutting rather than a one-time intervention for these species.