Red-necked longhorn beetle spreads across Japan, threatening fruit trees

The invasive red-necked longhorn beetle (Anoplophora chinensis) is expanding its range across Japan, causing significant damage to fruit trees and ornamental plants. The beetle's larvae bore into the wood of Rosaceae species, including cherry, plum, and peach trees, often leading to the death of the trees.

Recent reports indicate the species has reached the Chugoku region for the first time in Okayama Prefecture. In Fukui Prefecture, the beetle was recently confirmed in Oi Town, where authorities have identified damage to 49 trees. Because the larvae live inside the trunks for approximately two years, experts suggest the infestation may have been present longer than initially detected.

With no natural predators in Japan, the beetle's high reproductive capacity poses a serious threat to the agricultural sector. In Wakayama Prefecture, damage to plum and peach trees has reached approximately 11,000 trees. In response, the Ministry of Agriculture, Forestry and Fisheries and the Ministry of the Environment have established a task force to implement control measures. Local institutions, such as the Fukui City Natural History Museum, are displaying specimens and frass (larval excrement) to help citizens identify and report sightings to facilitate early detection.