Abstract
In March 2012, an outbreak of
Anoplophora glabripennis
was detected at Paddock Wood, Kent, UK. The epicentre of the outbreak was adjacent to a site that a company had used for storing ...imported stone in wood packaging. An eradication campaign was initiated involving the agencies responsible for plant health and forestry in England and Wales. The area was initially surveyed by visual inspection of standing trees from the ground and 24 infested trees were detected. This method was more effective for detecting trees with
A. glabripennis
exit holes than trees at an early stage of infestation. A further 42 infested trees were detected when the infested trees and host trees within 100 m of them were felled and the felled material was inspected. The most important host tree species was
Acer pseudoplatanus
(43 of the 66 infested trees). Tree climbers inspected the trees between 100 and 300 m of infested trees three times. They found damage caused by native pests that it had not been possible to detect from the ground but no
A. glabripennis.
Other surveillance techniques used were the regular inspection of favoured host trees over a wide area and the planting and regular inspection of favoured host trees in the core of the outbreak area. Pheromone trapping and the use of detection dog teams were trialled during the outbreak
.
Public meetings, leaflet drops, press releases, television features and school visits were all used to communicate with local residents and other stakeholders. No
A. glabripennis
were detected after the initial removal of trees in 2012 and eradication was declared after seven years of surveillance in 2019. The outbreak was likely to have been present for 10 or 11 years, but population development is likely to have been limited by the sub-optimal climatic conditions, especially the UK’s relatively cool summers.
The multidisciplinary ‘Phyto-threats’ project was initiated in 2016 to address the increasing risks to UK forest and woodland ecosystems from trade-disseminated Phytophthora. A major component of ...this project was to examine the risk of Phytophthora spread through nursery and trade practices. Close to 4000 water and root samples were collected from plant nurseries located across the UK over a three-year period. Approximately half of the samples tested positive for Phytophthora DNA using a metabarcoding approach with 63 Phytophthora species identified across nurseries, including quarantine-regulated pathogens and species not previously reported in the UK. Phytophthora diversity within nurseries was linked to high-risk management practices such as use of open rather than closed water sources. Analyses of global Phytophthora risks identified biological traits and trade pathways that explained global spread and host range, and which may be of value for horizon-scanning. Phytophthoras having a higher oospore wall index and faster growth rates had wider host ranges, whereas cold-tolerant species had broader geographic and latitudinal ranges. Annual workshops revealed how stakeholder and sector ‘appetite’ for nursery accreditation increased over three years, although an exploratory cost-benefit analysis indicated that the predicted benefits of introducing best practice expected by nurseries outweigh their costs only when a wider range of pests and diseases (for example, Xylella) is considered. However, scenario analyses demonstrated the significant potential carbon costs to society from the introduction and spread of a new tree-infecting Phytophthora: Thus, the overall net benefit to society from nurseries adopting best practice could be substantial.
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