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The goldspotted oak borer Agrilus auroguttatus Schaeffer is an invasive pest of three Quercus species in southern California, U.S.A. As a native and potentially indigenous exotic species, its distribution and potential damage is largely unknown in Mexico., We used the maximum entropy algorithm to determine the bioclimatic variables that may explain the distribution of A. auroguttatus, as well as its interaction with the distribution of known hosts in Mexico., Our model calculated high suitability for A. auroguttatus in the biogeographical provinces of California, the northern and southern areas of Sierra Madre Occidental and the northwestern area of the Mexican Plateau; moderate suitability was projected in the Baja California, Sonora and Sierra Madre Occidental provinces. Potential distribution of A. auroguttatus was overlapping with native ranges of Quercus agrifolia, Quercus emoryi Torrey and Quercus hypoleucoides A. Camus. Precipitation of the coldest quarter (23.6%), isothermality (23.5%), precipitation seasonality (17.3%) and mean temperature of the coldest quarter (11.2%) contributed most to explaining its distribution in Mexico., The geographical interaction (i.e. the likelihood that the habitat would be suitable for coexistence) of A. auroguttatus with its hosts in Mexico was projected in the California province (46 382.60 km2, probably as an exotic species) and the northwestern areas of Mexican Plateau and Sierra Madre Occidental provinces (74 013.45 km2, probably as native)., Determining the areas of environmental suitability for A. auroguttatus and its host distribution can focus ground surveys, contribute to management efforts and assist in the development of risk assessments for Mexico. [ABSTRACT FROM AUTHOR]

BACKGROUND The invasive goldspotted oak borer, Agrilus auroguttatus, is threatening the health and survival of oak trees in San Diego County, California. From two sites in the core area of the infestation, we report a 2.5 year investigation of the impact of A. auroguttatus on coast live oak, Quercus agrifolia, before and after treatment with two systemic insecticides, emamectin benzoate ( EB) and imidacloprid ( IC). RESULTS None of the 446 survey trees died during the study. The crown dieback rating of most trees at both study sites remained unchanged, regardless of insecticide treatment. A higher cumulative increase in the number of A. auroguttatus emergence holes was observed on trees that were previously infested and on trees with larger diameters. Over the 2.5 year period, the new infestation rates of initially uninfested trees across the untreated and treated groups were 50% ( EB) and 32% ( IC), and neither EB nor IC treatment affected cumulative increases in the number of emergence holes. EB-injected trees did not have significant annual increases in the number of A. auroguttatus emergence holes at either 1.5 or 2.5 years compared with that at 0.5 years, whereas untreated trees had significant annual increases. Although IC-injected trees had a significantly greater annual increment in the number of emergence holes than untreated trees during the last year of the study, treated trees had significant reductions in annual increases in emergence holes at both 1.5 and 2.5 years compared with that at 0.5 years. Untreated trees had no significant reduction in the annual increase in emergence holes at 1.5 and 2.5 years. CONCLUSIONS A. auroguttatus preferentially attacked previously infested and larger (diameter at breast height > 15-30 cm) oak trees, but the attacks led to very gradual changes in the health of the trees. Both EB and IC provided minor suppressive effects on A. auroguttatus emergence. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. [ABSTRACT FROM AUTHOR]

This pest survey card was prepared in the context of the EFSA mandate on plant pest surveillance (M‐2017‐0137), at the request of the European Commission. The purpose of the document is to assist the Member States to plan annual survey activities of quarantine organisms using a statistically sound and risk‐based pest survey approach, in line with current international standards. The data requirements for such an activity include the pest distribution, its host range, its biology and risk factors, as well as available detection and identification methods. This document is part of a toolkit that consists of pest‐specific documents, such as the pest survey cards, and generic documents relevant for all pests to be surveyed, including the general survey guidelines and statistical software such as RiBESS+. [ABSTRACT FROM AUTHOR]