Red-necked longhorn beetle infestation in Japan

The invasive red-necked longhorn beetle (Anoplophora chinensis) is expanding its range across Japan, posing a significant threat to the agricultural sector by damaging Rosaceae species such as cherry, plum, and peach trees. Larvae bore into the wood, often leading to tree death.

Initial reports highlighted the beetle reaching the Chugoku region for the first time in Okayama Prefecture, alongside damage in Fukui Prefecture and approximately 11,000 trees in Wakayama Prefecture. In response, the Ministry of Agriculture, Forestry and Fisheries and the Ministry of the Environment established a task force to implement control measures. In Fukui, authorities identified damage to 49 trees in Oi Town, noting that because larvae live inside trunks for approximately two years, infestations may exist longer than initially detected.

As the infestation persists, damage has been noted in Minabe Town, a major plum producer, where the number of affected trees has risen to 25. Local authorities have responded with specific countermeasures, including a task force in Minabe Town and an incentive program in Hyogo Prefecture. The Hyogo program offers digital gift certificates to individuals who report sightings of frass to facilitate early detection.

Recent developments confirm the spread of the beetle, also referred to as the Rubia japonica beetle, into new areas. In Amagasaki, Hyogo Prefecture, officials confirmed the first instance of damage to cherry trees on private land in the Tsukaguchi Honmachi area, noting the discovery of frass and actual tree damage. Additionally, in Achi Village, Nagano Prefecture, local authorities have established a response project team to protect approximately 10,000 peach trees from the infestation.