Ghent Combats 583 Knotweed Infestations Using Technology, Trees, and Sheep

Ghent (Eurotoday) – Ghent is tackling 583 outbreaks of Japanese Knotweed with the help of a digital tracking system and environmentally friendly strategies. Alderman Bram Van Braeckevelt emphasized the city’s innovative approach, which includes sheep grazing, tree planting, and cautious soil management.

As reported by VRT News, Japanese Knotweed was initially brought to Europe as an ornamental plant but has since become a serious invasive species across Flanders. In response, the city of Ghent has developed a digital platform that monitors the plant’s spread and outlines tailored action plans for each affected location.

Currently, Ghent is addressing 583 known infestations of the plant, each requiring a strategy tailored to the local environment and the severity of the outbreak. The campaign was detailed by Alderman Van Braeckevelt following a query from fellow council member Liesbet De Weder.

How is Ghent combating Japanese Knotweed without chemicals?

To avoid chemical use, Ghent uses various ecological techniques. Where feasible, authorities dig up and repeatedly cut the plant to deplete its energy reserves—a process that takes time and consistent monitoring.

In areas where digging could inadvertently cause the plant to spread, the city refrains from disturbing the soil. Instead, local vegetation—particularly trees—is encouraged to grow. Shade from the trees suppresses Knotweed growth, using natural methods to control the invasive plant.

One of the city’s more novel methods involves deploying sheep to graze on Knotweed in areas such as Gentbrugge. City officials say the sheep consume young shoots, gradually weakening the plant’s underground root system. Unlike machinery, sheep can reach difficult areas and also support the growth of other local flora.

Unlike some municipalities, Ghent has opted not to use electrical treatments to control Knotweed. Officials consider such methods unsuitable for the local context, citing potential risks. The city also ensures that construction practices don’t inadvertently spread the plant by carefully handling and controlling the movement of contaminated soil. While above-ground parts of the plant can be safely discarded, underground roots must be handled with care, as they can easily regrow.

Officials stress that Japanese Knotweed grows rapidly, displaces native species, disrupts ecosystems, and can even damage infrastructure due to its aggressive root system.