The pretty purple blossom of the summer lilac, the yellow flowers of the ragwort or the large white flower clusters of the giant hogweed: these plants are beautiful to the eye and seem harmless at first glance. But they are in fact invasive neophytes that can pose a threat to the environment. They will therefore be banned in Switzerland from September. Measures to prevent the spread of invasive neophytes are taken for every Swissgrid project. The steps taken include washing all tools and excavators before they are used again on another construction site. 

Combating invasive neophytes to support biodiversity

Neophytes are non-native species that did not originally occur in Switzerland. They were introduced by humans or brought into the country as crops or garden plants. The majority of these exotic plants are harmless or even enrich Swiss flora. However, some of them cause problems: they are invasive neophytes.

A danger to people and the environment

Invasive species are those known to pose a risk to biodiversity and ecosystem services or that could endanger humans and the environment if they were to spread in Switzerland. In Europe, around two percent of established non-indigenous plant species are considered invasive. They can impair the health of humans and livestock, harm native flora and fauna, and jeopardise agriculture and forestry. Invasive aquatic plants can also clog irrigation and drainage systems and restrict the electricity production of hydropower plants.

Rapid spread over green areas

Due to the potential of invasive neophytes to cause damage, specific measures must be taken to actively combat their growth. Swissgrid is taking various steps to prevent the spread of invasive neophytes in the green areas near its lines and substations. These plants spread rapidly and in large quantities, displacing native flora and fauna. The federal government has laid down the legal basis for combating invasive neophytes, including the Federal Act on the Protection of Waters, the Federal Act on the Protection of the Environment, and the Ordinance on the Handling of Organisms in the Environment. The measures that Swissgrid implements as part of each project are based on this legislation.

Pulling up and digging out neophytes; washing excavators

After completing each project, Swissgrid carries out follow-up inspections or verifications along the route for several years. If no more invasive neophytes are found within five years, the measures can be discontinued. If there are still neophytes in the area, the measures must be maintained. Swissgrid also takes regular action at its substations. To control the spread of neophytes, Swissgrid pulls them up, digs them out with an excavator, removes all the roots and regularly mows any grassland. Excavators must be thoroughly washed and disinfected after each use. This prevents neophyte seeds from being transported to another area by the excavator, where the plant can continue to spread. All tools are also washed and disinfected after each use.

Links

Background information: Invasive non-indigenous species (admin.ch, in German, French and Italian)