Swiss canton fights spread of Japanese beetle

Valais fights against the spread of the Japanese beetle Keystone-SDA

The invasive Japanese beetle has been discovered in Valais, southwestern Switzerland. The canton now wants to stop the spread of the voracious plant pest.

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Twenty specimens of the Japanese beetle were detected in the Rhone plain in Valais between the end of July and mid-September 2024 in the municipalities of Raron, Visp, Lalden, Brig-Glis, Naters, Ried-Brig and Termen, canton Valais said on Friday. Residents also found a single specimen in a house in Sierre.

The canton has issued bans and restrictions in the affected area. These relate to the transportation of compost, green waste, soil, potted plants and the cleaning of equipment and vehicles for ground work. Next year, the authorities will continue to control the pest using pheromone traps. In addition, the buffer zone will be monitored more closely.

The beetles were probably introduced by road from northern Italy or from the south side of the Simplon, the press release continued. Originally from Japan, the leaf horn beetle species has been detected in northern Italy since 2014 and in Ticino since 2017. Last year, the insect was found for the first time in Valais in the municipalities of Simplon and Zwischbergen.

+ Spread of Japanese beetle leads to lawn-watering bans in Basel

The Japanese beetle feeds on over 400 plant species. Adult specimens can cause great damage by eating the leaves, flowers and fruit of various plants, including apple trees, stone fruit trees and vines. The larvae feed on the roots of various grasses.

As it is considered a major threat to agriculture and the environment, the authorities regard the Japanese beetle as a priority quarantine organism. It must be reported in Switzerland as well as in the European Union.

+ How Switzerland is battling invasive species

Last summer the Japanese beetle caused FC Basel’s training pitch in Münchenstein to be closed. The footballers had to move to an alternative pitch to combat the insect.

Translated from German by DeepL/ts

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