13 research outputs found
How environmental managers perceive and approach the issue of invasive species: the case of Japanese knotweed s.l. (Rhône River, France)
We would like to thank Springer for publishing our article. The final publication is available at http://link.springer.com/article/10.1007%2Fs10530-015-0969-1International audienceStudying the perceptions of stakeholders or interested parties is a good way to better understand behaviours and decisions. This is especially true for the management of invasive species such as Japanese knotweed s.l. This plant has spread widely in the Rhône basin, where significant financial resources have been devoted to its management. However, no control technique is recognized as being particularly effective. Many uncertainties remain and many documents have been produced by environmental managers to disseminate current knowledge about the plant and its management. This article aims at characterizing the perceptions that environmental managers have of Japanese knotweed s.l. A discourse analysis was conducted on the printed documentation produced about Japanese knotweed s.l. by environmental managers working along the Rhône River (France). The corpus was both qualitatively and quantitatively analysed. The results indicated a diversity of perceptions depending on the type of environmental managers involved, as well as the geographicalareas and scales on which they acted. Whereas some focused on general knowledge relating to the origins and strategies of colonization, others emphasized the diversity and efficacy of the prospective eradication techniques. There is a real interest in implementing targeted actions to meet local issues. To do so, however, these issues must be better defined. This is a challenging task, as it must involve all types of stakeholders
Can Land Managers Control Japanese Knotweed? Lessons from Control Tests in Belgium
Japanese knotweed Fallopia japonica is an
extremely abundant invasive plant in Belgium and surrounding
countries. To date, no eradication method is
available for land managers facing the invasion of this
rhizomatous plant. We tested different chemical herbicides
with two application methods (spraying and stem injection),
as well as mechanical treatments, on knotweed
clones throughout southern Belgium. The tested control
methods were selected to be potentially usable by managers,
e.g., using legally accepted rates for herbicides. Stem
volume, height and density reduction were assessed after
one or two years, depending on the control method. Labor
estimations were made for each control method. No tested
control method completely eradicated the clones. Stem
injection with glyphosate-based herbicide (3.6 kg ha-1 of
acid equivalent glyphosate) caused the most damage, i.e.,
no sprouting shoots were observed the year following the
injection. The following year, though, stunted shoots
appeared. Among the mechanical control methods, repeated
cuts combined with native tree transplanting most
appreciably reduced knotweed development. The most
efficient methods we tested could curb knotweed invasion,
but are not likely to be effective in eradicating the species.
As such, they should be included in a more integrated
restoration strategy, together with prevention and public
awareness campaigns