Asian longhorn beetle is a native of China and is present in the Korean peninsula, and poses a serious threat to a wide range of broadleaved trees. It has caused extensive damage to trees in the USA and Italy since being accidentally introduced there in recent years.
We and the Food & Environment Research Agency (Fera) are working to eradicate a breeding population of Asian longhorn beetle (ALB) found in the Paddock Wood area of Maidstone in Kent. The existence of this population was confirmed by Forest Research scientists in March 2012.
Situation update, 13th June 2012
Close inspection of potential host trees after they have been felled has identified an infested tree, Ash-leaved Maple (Acer negundo), right at the northern edge of the current infestation zone. The larvae found in this tree were very young, which suggests that the adult beetle that laid the eggs only reached the tree last year.
The implications of this finding are that the current infestation zone will be extended by a further 100m northwards and all potential host trees within this area will need to be felled. Work is progressing to determine the exact number of trees to be felled in the extended area.
To date 65 trees have been found to be infested or highly likely to be infested. Over 100 live larvae have been recovered from tree samples taken within the infestation zone and this is expected to increase as further samples are analysed.
All potential host trees within the extended infested zone area are being mapped and the size, species and numbers of trees felled is being recorded. It is expected that the new finding on the edge of the infestation zone will extend the felling operation by two to three weeks, with expected completion towards the end of June, which is in advance of the anticipated main emergence period of the beetle. An incinerator for destruction of the felled material is now on site and in operation. It is expected that the incinerator will be on site for about another two weeks
Fortunately this outbreak was detected before the 2012 adult beetle emergence period, providing time to inspect and deal with infested trees.
Residents and landowners within the 2km buffer zone were asked to hold back from any felling/tree surgery or pruning of woody shrubs in gardens. This is because the beetle's larvae live in trunks and branches so it is important to make sure these are properly disposed of. Residents in this zone who do need to prune or fell trees or woody shrubs, have been asked to ensure that all woody material is taken to an appropriate Kent County Council waste transfer station or recycling site.
We urge everyone within the 2km buffer zone to keep a look out for the beetle or evidence of its presence to ensure the best prospects for eradicating this outbreak.
A public meeting was held at Hop Farm, Kent in April 2012 to provide local residents with information about the pest and the action being taken. Presentations about the biology of the beetle and the action being taken to eradicate it were provided by Fera and the Forestry Commission. The opportunity for questions and discussion following these presentations was well received.
A further public awareness exercise over the whole area (and nationally) took place in mid July 2012, just before the start of the adult beetle emergence period.
Tree professionals’ awareness
A meeting was held in April, 2012 at the outbreak site to provide information about the beetle to tree professionals based in the area, together with an opportunity for them to see the signs of infestation for themselves. This was aimed at helping them to spot the signs of the beetle during their working activities. About 120 people attended, and they responded positively to the action needed to eradicate this outbreak quickly
A leaflet about the beetle and what the public can do to help stop it spreading has been distributed to homes in the buffer zone (i.e. within a 2km radius from the edge of the infestation zone), including areas of Paddock Wood and East Peckham.
This pest is regulated, so movement of plants, logs and wood from infested areas is subject to statutory controls. Movement restrictions on host plants and woody material for two commercial retailers in the affected areas have been implemented by the Fera Plant Health & Seeds Inspectorate and Forestry Commission by way of plant health notices.
Some common native beetles can be mistaken for Asian Longhorn beetles. The adult beetles are large (about 20 - 40 mm long) and shiny black with variable white markings. Particularly distinctive are their antennae, which are longer than their bodies (up to twice the body length) and are black with white or light blue bands. They are almost identical in appearance to citrus longhorn beetle (Anoplophora chinensis), another non-indigenous longhorn beetle that threatens trees in Britain.
The most obvious symptoms of Asian longhorn beetle damage are the circular exit holes made by the emerging adult beetles in the trunks and branches, which are about 10 mm in diameter and are usually found in the main trunk and above.
Other signs which might be present, but less obvious, include piles of sawdust-like droppings at the base of infested trees, scraped bark, possibly sap bleeding from sites where eggs have been laid, and feeding damage on the bark of smaller branches and shoots.
We urge the public and industry, especially businesses receiving materials in wooden packaging from China or Korea, to keep a look-out for the beetle or evidence of its presence, and to report any sightings using our online form.
Or call us on 0844 2480071
If possible, the beetle should be caught and placed in a secure container such as a sealed glass jar so that an inspector can collect it. The beetles are not harmful to humans, although they should be handled with caution because they can nip the skin, although the nip is unlikely to penetrate the skin or draw blood. For most people the nip is likely to be no more uncomfortable than a nip by one of our larger native beetles. Nor is it poisonous.
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