Improving the management of Japanese knotweed s.l.: a response to Jones and colleagues

Abstract

In a recent paper, Jones et al. (2020a) claimed that we recommended the use of mowing for the “landscape management of invasive knotweeds” in an article we published earlier this year (i.e. Martin et al. 2020), a recommendation with which they strongly disagreed. Since we never made such a recommendation and since we think that, in order to successfully control invasions by Japanese knotweed s.l. taxa (Reynoutria spp.; syn. Fallopia spp.), stakeholders need to acknowledge the general complexity of the management of invasive clonal plants, we would like to (i) clarify the intentions of our initial article and (ii) respectfully discuss some of the statements made by Daniel Jones and his colleagues regarding mowing and knotweed management in general. Although we agree with Jones et al. that some ill-advised management decisions can lead to “cures worse than the disease”, our concern is that the seemingly one-sided argumentation used by these authors may mislead managers into thinking that a unique control option is sufficient to tackle knotweed invasions in every situation or at any given spatial scale, when it is generally admitted that management decisions should account for context-dependency (Wittenberg and Cock 2001; Pyšek and Richardson 2010; Kettenring and Adams 2011).