History of discoveries and management of the Citrus longhorned beetle, Anoplophora chinensis, in Europe

Authors: HERARD, FRANCK - European Biological Control Laboratory (EBCL); MASPERO, MATTEO - Fondazione Minoprio

Submitted to: Journal of Pest Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/25/2018
Publication Date: 7/9/2018
Citation: Herard, F., Maspero, M. 2018. History of discoveries and management of the Citrus longhorned beetle, Anoplophora chinensis, in Europe. Journal of Pest Science. 92:117-130. https://doi.org/10.1007/s10340-018-1014-9.
DOI: https://doi.org/10.1007/s10340-018-1014-9

Interpretive Summary: The citrus longhorned beetle, Anoplophora chinensis (CLB), is a large wood-boring insect native to East Asia that has been reported to attack many species of deciduous trees, in 26 families. It is a major pest of citrus in Japan. Larvae bore into the trees near the ground, tunnel in the heart wood and can kill trees. The larvae can take one-to-two years to develop, so they can be mistakenly imported inside bonsai plants and young trees for transplanting. Since 1980, CLB has been accidentally introduced over 100 times in a total of 11 European countries, putting at risk a wide range of broadleaf trees. CLB has also been detected five times in Washington state between 1999 and 2001, but the only established infestation were successfully eradicated after expenditure of $2.2 million, and no detections have occurred since 2002. We present the history of 38 years (1980 - 2017) of CLB, including interceptions, discoveries of infestations, eradication activities, European Union management regulations, and the current situation. The European Union developed regulations requiring the timely reporting of new infestations and aggressive efforts to eradicate them. It also helps to finance eradication efforts when member countries comply with the regulations. In consequence, CLB has been eradicated in 9 of 11 European countries reporting detections. However, infestations in northern Italy were not quickly detected, and initial management responses were inadequate, leading to the eventual infestation of 46 municipalities. Over 50,000 trees have been destroyed in a sustained attempt to contain and eradicate the insect, but it is still present in 41 municipalities and almost 2000 infested trees were detected in 2016. The experience with CLB provides an example of the value and efficacy of surveillance and rapid response programs to prevent costly long-term impacts from invasive forest insect pests.

Technical Abstract: The citrus longhorned beetle (CLB), Anoplophora chinensis (Coleoptera: Cerambycidae), is a wood-boring beetle native to eastern Asia, where it is a major pest of citrus. It attacks many species of broad-leaved trees. The larvae bore into the trees near the ground, and can kill trees. Expanding international trade, especially of bonsais and nursery trees imported from eastern Asia, has led to introduction of CLB in Europe where it is currently a serious threat to ornamentals, the tree nursery industry, urban trees, and is a potential threat to natural forests and the citrus industry. We present the history of 38 years (1980 - Dec 2017) of CLB interceptions and discoveries of infestations in Europe; eradication activities, which are based on the CLB management rules developed by the European Union; and the current status of CLB infestations in Europe. There have been 115 reports of detection of CLB in 11 countries since the first report in 1980 (59 interceptions, and 56 infestations, of which 49 were found in Italy). CLB is reported as eradicated from 9 of the 11 countries as of December 2017, but populations are still established in Italy and Croatia. CLB has also been detected five times in Washington state, USA, between 1999 and 2001, but all infestations were successfully eradicated, and no detections have occurred since 2002.