Pests Valais fights against the spread of the Japanese beetle

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

20 specimens of the Japanese beetle were detected in the Valais Rhone plain between the end of July and mid-September 2024 in the municipalities of Raron, Visp, Lalden, Brig-Glis, Naters, Ried-Brig and Termen, the canton of Valais announced 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.

Presumably from Italy

The beetles were probably introduced by road from northern Italy or from the south side of the Simplon, the press release continued. The leaf horn beetle species, which originally comes from Japan, 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.

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.

Last summer, the Japanese beetle caused FC Basel's training pitch in Münchenstein BL to be closed. The professionals of the first team had to move to an alternative pitch due to control measures against the insect.

SDA