Herbicides and Japanese knotweed
The majority of Japanese knotweed herbicide treatments use glyphosate as the main active ingredient. This is based on decades of experience and academic research, especially a recent field trial which confirmed optimum methods and frequency/timings to achieve best control in the long term.
Glyphosate has been subject to many years of intense debate regarding its safety, but in the UK, Europe and the US, glyphosate-based herbicides continue to satisfy the very highest standards of critical assessment for safety in use and to the environment.
Glyphosate has a unique advantage for use against perennial invasive weeds like Japanese knotweed and Giant Rhubarb, Bamboo etc. which is its ability to move through the vascular system (so-called systemic herbicide) to accumulate in root structures thereby preventing, after several years, new growth emerging each year. This unique benefit helps in the fight against the most ‘aggressive’ invasive weeds and consequently the battle to manage their damaging impact on habitats and biodiversity.
However, it should be remembered that glyphosate is a non-selective herbicide so it must always be used cautiously where there are non-target plants and especially when used on or near water (glyphosate is approved by Government for use in these situations, once a suitable permit is obtained, but application methods still need to be targeted to optimise dose and achieve accurate delivery).
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Japanese Knotweed Management >>