A review of the host range of C. parasitica (CABI Crop Protection Compendium, 2013), identified species of Castanea and Quercus as the most important susceptible taxa.

Castanea dentata) and the European chestnut (C. sativa) are considered to be the worst affected, though the European chestnut is considered to be less susceptible due to the presence of a virus which can infect strains of C. parasitica. The virus has been shown to reduce disease and promote canker healing.

Other non-European Castanea spp. are reported to have a range of disease susceptibilities to C. parasitica. All are considered much less susceptible to the pathogen than the European or American sweet chestnuts none however are immune, despite having co-evolved with the pathogen.

In addition to Castanea ssp. a number of Quercus spp. have been reported as being infected with the disease. In many cases the affected trees are associated with mixed plantations of Quercus spp. and C. sativa. The paucity of reports of diseased oaks from Europe which were not associated with infected C. sativa suggests that European oak species are mainly incidental hosts. Q. virginiana and Q. stellata are the only oaks in North America to be seriously affected.

Cryphonectria parasitica, a fungus which causes Chestnut blight, is native to eastern Asia and is now widespread in North America and many European countries. It was first detected in the UK in November 2011 following the import of infected planting material and statutory eradication measures were implemented. The pathogen, for which a Protected Zone is in place, is not currently considered to be present in the UK.

Statutory action against Cryphonectria parasitica is a requirement of the EU Plant Health Directive 2000/29/EC. The pathogen is listed in Annex II/AII of Council Directive 2000/29/EC. Currently the requirements are that plants of Castanea and Quercus, intended for planting, other than seeds, must be free of C. parasitica and originate either from a Pest Free Area, or from a place of production where no symptoms of the organism have been observed, including in the immediate vicinity, since the beginning of the last complete cycle of vegetation. However, evidence regarding the potential for there to be a significant latent period between the time of infection of Castanea and the emergence of symptoms suggests that the current requirements are not providing sufficient assurances of freedom, when the material originates in a nursery which is not situated in a Pest Free Area. The current Protected Zone requirements in Annex IVB of the Directive do not provide protection against the introduction of infected planting material, as they are restricted to wood and bark.

Should the pathogen enter the UK, eradication could be achieved if infection was detected soon after import of the plants via the destruction of infected plants and all other plants from the same lot. A survey of hosts in the surrounding area over a minimum period of 2 years would also be required, to ensure spread has not occurred prior to the identification of infection. It is also recommended that Forestry surveillance of C. sativa should be stepped up in the south of the UK, to demonstrate freedom form C. parasitica.

This Rapid Pest Risk Analysis is based on the current available data and literature. There remain uncertainties in the analysis, particularly regarding risks posed by hosts other than Castanea, whether there may be a northern limit on the potential spread of this pathogen, and the short and long term role which hypovirulence could play in the UK. These uncertainties are, however, unlikely to be addressed by a more detailed PRA at this time. If available, further information on uncertainties identified in the rapid risk assessment should be included in any response to this consultation.

A more detailed PRA is not recommended at this time.

Statutory action is required, the following measures are recommended:

General requirements -

• Protected Zone for the UK should be extended to include Castanea plants for planting, including seed, with the requirement that any plants moving into and within Protected Zones should originate either from a Pest Free Area or a Protected Zone.
• The UK Protected Zone should be extended to include the Isle of Man.
• Forestry surveillance of C. sativa should be increased in the south of the UK, to demonstrate freedom form C. parasitica.

For outbreaks -

• Destruction of infected plants and all other plants from the same lot.
• Survey of hosts within the surrounding area over a minimum period of 2 years.

Platanus x acerifolia (London plane), Platanus occidentalis (American Sycamore, American plane tree) and Platanus orientalis (Oriental plane).

Platanus x acerifolia and P. orientalis both have a considerable presence in the UK. Some plantings of P. orientalis occur in England and Wales.

A serious disease of plane trees both in the USA and Europe, C. platani has killed tens of thousands of plantation trees and street trees in the eastern United States, California, and southern Europe. Infected trees typically die within 3-6 years.

The pathogen is already present in Europe and, despite current EU wide legislation designed to limit its further spread, the pathogen is still spreading in France and other southern member states. Although it is moderately likely that the pathogen could enter the UK, the likelihood of establishment is assessed as very uncertain because, although hosts are widespread and the known climatic responses suggest that the climate is suitable, since its arrival 70 years ago the pathogen has spread widely in southern Europe but has never been reliably confirmed north of a latitude approximating to Geneva.

If the pathogen establishes, large economic impacts may occur. Felling, removal and destruction of infested material would be very costly. Biosecurity measures during clean up operations to prevent further dispersal of the pathogen would need to be stringent and therefore add to the cost. Plane trees are a very common urban tree and if the disease becomes widespread, several major UK cities would lose a considerable proportion of their trees from parks, roadsides and squares. This could affect the character of certain cities and ultimately have adverse affects on tourism and access to green spaces for the residents.

The Plant Health (England) (Amendment) Order 2013, which came into force in January 2013 strengthened existing EU measures to limit the spread of this pathogen through the introduction of statutory notifications requirements for all imports of Platanus (Plane), along with several other genera of trees. A major uncertainty is the risk that the pathogen could be introduced via asymptomatic host planting material and associated soil / growing media. Although not all imported material can be checked, the notification requirements enable further evaluation of this risk through the development of a surveillance strategy, enabling targeted inspection of the highest risk imported planting material i.e. trees imported from areas where the disease is known to occur. Trees showing damage or suspicious symptoms would be submitted for more detailed laboratory examination and testing for the presence of the pathogen.

• Statutory action against Ceratocystis platani is a requirement of the EU Plant Health Directive 2000/29/EC.
• Statutory notification of imported plants has been introduced as a supplementary measure.
• The introduction of a surveillance strategy to target inspections at the highest risk imported planting material, with any plants exhibiting suspect symptoms to be submitted for laboratory testing.
• The need for additional action (e.g. EU Protected Zone status) to be reviewed in response to evidence emerging from the surveillance programme.

Information on the host species for the pest is unclear. The main hosts in the beetle's home range are reported to be Prunus species, in particular peach and apricot, and to a lesser extent plum and cherry.

However, the full extent of the host list for this beetle is not at present known and is likely to be much wider than just those species referred to above. There are for example references that suggest other species which may also be at risk include willow, elm, oak, maple, walnut, crab apple and pine.

One of the key challenges in completing a RA for this pest is that much of the data that exists in Europe is from a secondary source, the original information coming from China. Whilst a more detailed PRA and review of such information is considered unlikely to change the outcome of the RA for the UK. To help inform the appropriate action to be taken at the EU level for this pest a more detailed PRA including a review of such information would be required.

The beetle's distribution currently appears to be limited to Asia including most of China, with particular prevalence in northern and central provinces, North and South Korea, Mongolia, Taiwan and Vietnam. In Europe outbreaks have been recorded, seven in Italy and one in Germany and eradication measures are ongoing.

The UK and the USA have reported a single interception. The UK interception was of three adults (two alive) in wood packaging material believed to originate from China. A pathway associated with the interception of a number of invasive longhorn species of concern.

In its native range the beetle has been recorded as infesting between 30 to 100% of fruit trees in a crop and of causing considerable damage to peach, apricot and plums, though no records were available regarding actual crop losses. Cherry, poplar and plum are likely to be of significant concern to the UK, with plums alone having an estimated value of £12 million to the UK markets.

There is some debate over the pest's ability to develop and establish under different climatic conditions such as those experienced in the UK. However, experience of other longhorn beetles, the outbreak in Bavaria in Germany and the hosts native range including the Northern regions of China and Mongolia would suggest it is possible.

Although the most likely pathway for entry into the UK is considered to be infested wood packaging material originating in the pests native range. There is also a possible risk for plants for planting originating in Europe, where outbreaks have been known to occur. It is suggested that the recent Plant Health (England) (Amendment) Order 2013 that requires prior notification of all Castanea, Fraxinus, Platanus and Quercus plants for planting imports from the EU be extended to Prunus and Populus. National measures could also be considered against imports of Italian host trees in particular, by requiring imports only from pest free areas and by actively targeting plant material for inspection.

Defra recommends statutory action based on the three options proposed:

• Option 1 - Statutory action on findings + an awareness raising campaign across the PHSI and industry, + support proposals for ISPM 15 to be introduced for all intra-EU trade as well as 3rd country imports. In addition Neil Giltrap would raise at EPPO to try and push for the RA to be put on the agenda for discussion at SC. Or a joint PRA could be pursued with Germany.
• Option 2 - Option 1 + the introduction of a requirement for imports of host species from Italy to be notified (could be voluntary/statutory notification).
• Option 3 - Option 2 + national measures requiring material to originate from a Pest Free Area (PFA) + active targeting of inspections on Italian imports.

European mountain ash ringspot associated virus (EMARAV) is the tentative name of a virus obtained from symptomatic S. aucuparia. Symptoms of ring-spots and line patterns on the foliage of affected trees was first recorded in 1960 and further reference to the presence of symptomatic S. aucarpia in Finland and the UK was made in 1979 where diseased trees are described as frequently occurring.

Economically mountain ash is used as an ornamental species in parks and gardens and for decorative carpentry. EMARaV-infected mountain ash trees suffer from chlorosis and growth reduction of varying severity, which impairs the value for ornamental and carpentry use. Although it is unclear from the information available as to whether it actually killed trees, there are reports of trees suffering a slow dieback within a few years of symptoms first being observed.

The distribution of the virus is not known within Europe the symptoms and/or the virus have been reported from the Czech Republic, Finland, Germany, Poland, Sweden and the UK. Within the UK the virus is known to be widespread in NW Scotland and the Central Highlands. The distribution could be even more widespread given the availability of the host species. However to date, there was no evidence available to show that it had spread to the rest of the UK despite having been present for at least 30 years. Neither does it appear to have had a significant impact on populations of mountain ash in areas where it is known to occur.

D. decempuncta is one of the most commonly intercepted whitefly species in England and Wales. Since 1996, it has frequently been found on imported aquatic plants at exceptionally high densities. Statutory action has been taken against D. decempuncta on two occasions, when it was found infesting 30 plants of Echinodorus radican and Piper sarmentosum imported from Singapore in 2003, and Limnophila plants imported from Singapore in 2012.

The pest is a tropical species native to southern Asia, which has spread to Australia, the Pacific Region and the Middle East. It is very unlikely to naturalise and overwinter outdoors in Britain. It has been regularly intercepted in the UK for a decade on growing plants, and no incursions have so far been reported. The pest is broadly polyphagous and it is therefore possible that it could transfer from aquatic plants to other ornamental plants grown under protection in the vicinity.

The pest can breed on a range of glasshouse vegetable crops, including aubergine, cucumber and tomato, although it has not been recorded having an economic impact on these crops and there is no clear pathway from protected ornamental plant collections to commercial vegetable glasshouses.

No statutory action

Furthermore the pest is not of sufficient concern to justify a more detailed PRA

P. solenopsis is polyphagous feeding on more than 200 plant species assigned to approximately 60 families, with a preference for Asteraceae, Euphorbiaceae, Fabaceae, Malvaceae and Solanaceae. It feeds on a range of important crops grown in the UK, including asparagus, peppers, tomato, aubergine, potato and grapevine. It also feeds on many ornamental plants.

P. solani is polyphagous feeding on plants belonging to at least 31 families, with a preference for Asteraceae and Solanaceae. It feeds on a range of important crops grown in the UK, including cabbage, peppers, tomato, aubergine and potato. It also feeds on important flower crops, such as chrysanthemum, and on many common weeds, such as common sowthistle.

P. defectus is polyphagous feeding on plants belonging to nine families. It appears to show a preference for Asteraceae and Crassulaceae. None of its host plants are of major economic importance in the UK.

Due to the taxonomic uncertainty, which is unlikely to be resolved soon, leading to possible confusion in the literature, all three nominal species (Phenacoccus solenopsis, P. defectus and P. solani) are considered together in this rapid assessment. None are listed in the EC Plant Health Directive, or in any of the EPPO lists.

P. solenopsis is a highly invasive agricultural and horticultural pest that has recently been introduced to Europe (Cyprus) in 2010. In Cyprus it has had a high impact on a range of ornamental plants grown in urban areas, and a medium impact to non-commercial production of aubergine, grapevine, okra and tomato. There have been multiple interceptions of P. solenopsis in England on fresh vegetables from West Africa, and most recently on herbs from Israel and bell peppers from East Africa. Both P. defectus and P. solani have also been introduced to the EU. P. defectus/solani (identity is uncertain) has been found breeding and causing serious damage to succulent plants at a public botanical garden and in private plant collections in the UK.

Statutory action should be taken if found on plants for planting as the most likely pathway for entry and two of these nominal species, P. solani and P. solenopsis, could transfer between hosts and cause serious damage to tomatoes. Interceptions have been made on imported herbs and there is some concern that action should be taken on this commodity if there is the potential that these herbs could be planted, rather than being already cut.

These pests are likely to present more of a risk to southern EU countries than the UK.

The pest is not of sufficient concern to justify a more detailed PRA.

Statutory action should be taken if found on plants for planting, and imported herbs suitable for planting.

The pink tea mite is an invasive species outside its native range and as such there are some aspects of the biology of this species, for example, the damage caused in its current distribution, its host range, cold hardiness and host plant preferences, which could be investigated in more detail. However, these factors do not impact on the overall conclusion of the Rapid Assessment, which is a recommendation for no statutory action. A full PRA is not therefore required. The pest is now established in at least four European countries, and probably goes un-noticed in others. It is not a high priority.

Furthermore the pest appears to have been present in the UK for a number of years, has already had the opportunity to spread widely and is very likely to be present (undetected) at camellia growers nurseries in the UK. It is very difficult to detect because of its small size and consequently it would be very difficult to prevent spread of this pest. The pest appears relatively straightforward to control, and as it is one of an assemblage of mites and insect pests on camellias, it will probably be controlled by generic control measures for camellia pests. Spray programs appear to have successfully controlled the pest where it has occurred to date in the UK.

Agrilus anxius

Agrilus anxius Summary

The European and Mediterranean Plant Protection Organization (EPPO) have produced the attached draft Pest Risk Analysis (PRA) and datasheet for A. anxius following concerns raised regarding the increasing trade of wood chips from North America, which might constitute a pathway for the entry of the pest into the EPPO region. The PRA also considered the risk from imported plants for planting (Betula Spp.), and other wood products such as logs for power stations and furniture.

The PRA concluded that there is a high risk of establishment and spread if the pest is introduced into the EPPO region and that if this occurred it would have major economic and environmental consequences. The probability of entry of the pest from the identified pathway was assessed as low to moderate. The PRA concluded that management measures to prevent the introduction, establishment and spread of the pest are appropriate and a number of recommendations were made.

In responding to the consultation we would be particularly keen for views on the proposed management options in the PRA, for example, would they be practical from an industry perspective and about the level of trade, and sources of material.

Defra recommends a two stage approach to the introduction of measures.

In the short term:

• A publicity/awareness raising campaign
• Possible national measures (based on the PRA)

Longer term:

• Push for EU wide measures based on the PRA

Aleuroclava jasmini is a polyphagous whitefly, of most concern to the EU and EPPO as a pest of Citrus and some ornamentals. However, there are no records describing significant plant damage and it is possible that this is only a minor pest of Citrus. It has spread from Asia throughout the warmer parts of the world. It is reported from Croatia but its status is unclear.

In the absence of phytosanitary measures the whitefly is likely to continue to enter the UK. With the information that we currently have available on the whitefly it is not of sufficient concern to the UK to justify a more detailed assessment. No specific management options are available. Destruction of infested plants and precautionary treatment of those remaining may be the simplest and most straightforward way of achieving eradication.

The host plant genus that is of most economic importance in Britain is Prunus, because of the fruit crops cherry and plum. A. psidii also feeds on several genera grown as ornamentals in Britain: Celtis, Citrus, Morus, Prunus, Salix and Sambucus.

The host plant genus that is of most economic importance in Europe is Citrus, although there do not appear to be published records of A. psidii causing economic damage to citrus.

Aleuroclava psidii has been detected on at least 46 occasions in England and Wales since 1997 on imported produce, mainly guava leaves used for packing fruit from India and Pakistan. A live puparium was recently detected on a bonsai Chinese bird plum tree (Sageretia theezens) imported from Hangzhou, Zhejiang Province, China.

Unlike other Asian whitefly species that have spread (for example Dialeurodes citri) A. psidii has so far only been recorded in the Andaman and Nicobar Islands and within mainland Asia. This suggests that it may have limited ability to colonise new areas, even when it is carried to areas where hosts are available and the climate is suitable. A. psidii has not demonstrated much capacity to invade new geographical areas.

A. psidii is likely to be restricted to protected ornamental plants and may be controlled by using the same products used against the regulated whitefly pest Bemisia tabaci. With the information that we currently have available on the whitefly it is not of sufficient concern to the UK to justify a more detailed assessment. The EU and EPPO will be notified as it may be more of a concern to southern member states with its hosts including Citrus.

The pests current geographical distribution is North America, Central America and Oceania. A UK pest risk assessment (PRA) was produced for this pest in 1993, however this was written at a time when the EU, including the UK, did not import Capsicum from countries where the pest was known to be present.

Following a serious outbreak in the Netherlands during July 2012 in four glasshouses used for the production of Capsicum a review of the UK PRA was undertaken. The review concluded a moderate risk of entry for the pest from Mexico, southern USA, central America and Oceania and that establishment outdoors in the UK was unlikely given the cooler climate and limited host availability. Experience indoors in other countries suggests that establishment is very likely in such conditions. However transfer to a growing crop would depend on the extent of hygiene measures in place at packing and production facilities. Outbreaks in protected Capsicum production are likely to cause serious impacts because detection of even a serious outbreak can be difficult and there is no reliable method of control. Crop destruction is likely to be the only method available.

To prevent entry, listing of the pest in Annex IAI and the inclusion of fresh Capsicum from North America, Central America and Oceania in Annex IVAI are the only clear risk management options available.

Although a more detailed PRA is not recommended on the basis that little additional useful information is likely to be available, if recommended for listing further consideration of the impact to southern EU Member States may be beneficial.

Bemisia tabaci
(Tobacco Whitefly)

Consultation letter

List of consultees

Consultation paper

Consultation outcome

Ceroplastes rubens has been intercepted on several occasions in England and Wales and statutory action has been taken twice to prevent the introduction of the scale insect (on an unspecified plant, 2007, and Aglaonema, 2011). However, although C. rubens occurs widely in tropical, subtropical and warm temperate areas, it is very unlikely to be able to overwinter outdoors in the UK and therefore establishment will be restricted to protected ornamental plants.

It is an important economic pest of many tropical and subtropical crops, and citrus, none of which are grown as commercial crops in the UK. It may have a small impact on the aesthetic quality and market value of indoor ornamental plants but there is little data available to quantify the economic implications. In the absence of phytosanitary measures the scale is likely to continue to enter the UK. It may be controlled using the same products used for other soft scales already present in the UK.

The rapid assessment was undertaken to determine if continued statutory action is justified.

No Statutory Action

With the information that we currently have available on the pest it is not of sufficient concern to the UK to justify a more detailed assessment.

Based on its biology and low potential impact continued action on this pest in the UK would not be considered appropriate. It is likely to be of more concern to southern Member States of the EU, as it is an economic pest of citrus.

Ceroplastes rusci has been detected on many occasions in England and Wales and statutory action has been taken to eradicate incursions of the scale on five occasions.

C. rusci occurs widely in tropical, subtropical and warm temperate areas. It is unlikely to be able to overwinter outdoors in the UK and therefore establishment is likely to be restricted to protected ornamental plants. All previous populations on indoor plantings have been transient.

With the information that we currently have available on the scale it is not of sufficient concern to the UK to justify a more detailed assessment. It is already present in many areas of Europe and the Mediterranean where its most economically important hosts are found. As such a recommendation for no statutory action is proposed.

See covering letter here
Consultation Outcome

An eradication or suppression strategy is proposed depending on the outcome of surveillance into the extent that C. fraxinea is already present.

The beetle is very common and widespread on the continent. There is free movement of its host plants within the European Union and recent findings in Kent and Norfolk may have resulted from beetles being blown across the channel or being brought in accidentally on transport.

It is likely to be able to naturalise, at least in southern England, wherever mint is grown. This is what has recently happened with the closely related rosemary beetle, C. americana, which is native to southern Europe, but is now widely naturalised on rosemary across much of the UK.

C. coerulans is not recorded as an economic pest of commercial mint production in Europe, although it is recorded damaging mint in gardens. In some circumstances it is likely to cause serious damage (complete defoliation) to individual cultivated plants in private gardens. On rare occasions, management action may be required in commercial mint crops. Potential yield losses are likely to be small, although it may be more important in organically grown crops. It is unlikely to have any significant impact on biodiversity, ecosystems and forestry in the UK.

In the absence of phytosanitary measures the beetle is likely to continue to enter the UK and measures would be difficult to implement for casual introductions. It is most likely that this beetle will turn up in private gardens, rather than at commercial premises, which could restrict management options.

This is a highly polyphagous pest, the larvae boring into fruit, seeds and stems of plants in many different families.

Economic hosts grown in the UK include Allium cepa (onion), Malus (apple), Prunus (plum, cherry), Pyrus (pear), Vitis vinifera (grape vine), and Zea mays (maize).

Other recorded hosts include Castanea (chestnut), Citrus, Curcuma longa (tumeric), Durio zibethinus (durian), Elettaria cardamomum (cardamom), Helianthus annuus (sunflower), Punica granatum (pomegranate), Quercus acutissima (Japanese chestnut oak), Ricinus communis (castor oil plant), Tectona grandis (teak), Theobroma cacao (cocoa tree), Zingiber officinale (ginger), and many others.

This is a complex of species, and incomplete information on their separation has been published to date, reports have suggested that there may be around 20 species in the genus. Since the number of species within the complex is unknown and their biology cannot be distinguished, this assessment has been made on information on all putative species within the C. punctiferalis species complex. An attempt has been made to separate southern and northern populations in this rapid PRA, which have been assumed to have different levels of cold-adaptation and thus differ in the risk posed to the UK.

Live larvae were first intercepted in England and Wales in 2007 and, in 2011, 13 interceptions of larvae were made. Statutory action was recommended on consignments of fruit with the pest due to reports of damage to apples in Northern China (CABI, 2011), these UK findings were considered to be significant and a rapid PRA was requested to clarify the threat to the UK. The pest is a concern to the NPPOs of several countries including New Zealand, South Africa, Canada and the USA.

For the UK, statutory action is only appropriate for imports from northern populations (i.e. China, Korea and Japan) when the pest is found on plants for planting (on any type of plant), and on certain temperate fruit produce (e.g. apple, plum, cherry, and pear).

Statutory action is not recommended when the pest is found on other hosts including tropical or sub-tropical produce, especially those on which the pest has already been detected such as Annona squamosa, Psidium sp. and Mangifera, as the pest would not be expected to survive in the UK.

C. maculipennis is a polyphagous species that has been recorded from eight plant families with the greatest number of separate hosts recorded from the Solanaceae. However, the primary hosts appear to be species of Dendrobium orchids, and possibly also bitter gourd (Momordica charantia), although reduction of fruit yield on the latter has not yet been reported.

The pest is not known to be present in the UK; it is known only from interceptions at UK points of entry. It was intercepted on four occasions in 2011, in each case on a consignment of orchids from Thailand.

A Dutch PRA already exists for this pest (van der Gaag et al., 2007). This Rapid Assessment was requested for this pest to help identify the most appropriate actions to take when it is intercepted.

This pest has been intercepted by the PHSI on six occasions since 2006, with statutory action being taken twice. It is found in Central and South America and also southern USA, and appears to have spread in plant trade; recorded in Hawaii, Maderia, Germany and France. UK interceptions were made on plants from Malaysia, Mauritius and Singapore, which are all first records for these countries and it is suspected it may be more widespread than reported in the literature as the puparia are translucent and difficult to detect.

Very few of the known host genera are grown outdoors in the UK, being mostly unable to survive harsh winters. They are mainly kept as household ornamental plants and the pest is therefore most likely to find hosts under protection. The optimum conditions for development (23.4°C, 70% humidity), suggests that areas most at risk would be botanical collections with 'tropical glasshouses', their optimum humidity being higher than would normally be found in domestic situations.

The rapid assessment is being carried out to determine whether this pest should be notifiable and if statutory action against it should continue.

No Statutory Action

With the information that we currently have available on this whitefly it is not of sufficient concern to the UK to justify a more detailed assessment. As such a recommendation for no statutory action is proposed.

Consultation letter

EPPO PRA

Consultation outcome

A highly polyphagous pest, which can cause significant damage to a number of cultivated berry and stone crops, including Prunus spp. (mainly sweet cherries, but also on peaches and apricots), Vaccinium spp. (blueberries), Rubus spp. (e.g. raspberries and blackberries) and Fragaria anannassa (strawberries). Grapes are probably not a significant host, but further investigations are needed to determine whether this applies to all varieties. Likewise, other soft fruits, e.g. gooseberries, currants (red and black) and plums are not thought to be major hosts. It also attacks wild hosts, such as wild blackberries, which makes it a particularly challenging pest to control.

This pest, unlike other vinegar flies lays eggs within ripening fruit (rather than ripe fruit) while they are still attached to the plant (i.e. well before harvest) and this can lead to severe crop losses. SWD is also highly mobile, being an active flyer and able to move onto crops from wild hosts, where they overwinter.

The attached PRA prepared by an EPPO Expert Working Group in July 2010, concluded that "based on the current knowledge there is a strong probability that SWD could cause significant yield loss and reduction in crop quality". In addition, only the very northern areas of Europe are unsuitable in terms of climate, with all of England and Wales (and most of lowland Scotland) being at risk.

There is no EU regulation of SWD, and this is unlikely to change. The response of other European countries to their findings to date has been focused on trapping surveys to monitor for pest presence, advice on Integrated Pest Management (IPM), information campaigns and destruction of infested host material. Many countries in the EU are now carrying out research into the biology of the pest and the efficacy of different control measures; adapting these measures to develop strategies appropriate to their geographical location and fruit production industries.

• No statutory action, leave to industry to manage
• Work in collaboration to limit spread including limited statutory action when necessary

Further information on the advantages and disadvantages for each option is provided in the attached PRA cover note.

Fusarium oxysporum f.sp. lactucae

Consultation letter

A fungal pathogen which is the cause of a wilt disease of lettuce. Refer to the Rapid Assessment summary for further information.

Lettuce is an important crop in the UK with a 'field-gate' value of £82 million in 2008 (Defra, 2008). It is thought that F. oxysporum f.sp. lactucae is specific to lettuce (Lactuca sativa) and lamb's lettuce (Valerianella locusta) and it is likely that other species are not at risk. The pathogen is known to occur in the EU, having been recorded in Italy in 2001 and Portugal in 2004. It is also present in the USA (the main source of UK seed), parts of Asia and possibly Brazil. As far as is known, this pathogen is not established in field-grown or protected lettuce in the UK. However, there have been no specific surveys for the pathogen. The pathogen has never been regulated, trade in lettuce plants and lettuce seed into and within the EU are not specifically regulated under phytosanitary legislation. This means that the pathogen has not been restricted in its movement and may have already entered the UK. Therefore there may be implications for the prospects of eradication.

The two possible options are outlined below. The recommendation of the RA is that no statutory action is taken.

1. Immediate move to no statutory action in the event of any future outbreak - i.e. industry management

2. Statutory action against initial outbreaks, but keeping under review and moving to no statutory action if eradication/containment is not achievable.

Further information on the advantages and disadvantages for each option is provided in the attached rapid assessment and summary note.

Liriomyza spp.
(Leafminers)

Consultation letter

Consultation paper

Cost benefit analysis

List of consultees

Consultation outcome

The aim of this review is to consider whether or not the UK should introduce (or retain, in the case of L. bryoniae) a PZ for some or all Liriomyza species. During the late 1980s through to the mid 1990s Liriomyza spp., in particular L. huidobrensis, outbreaks were prolific in UK ornamental production premises and to a lesser extent, commercial salad producers. Since then the numbers of outbreaks have gradually fallen and in recent years appear to have been restricted to outbreaks on imported plant material.

Since 2009 there has only been one recorded outbreak of L. huidobrensis in the UK (in 2011), despite an increase in interceptions from Third countries in recent years. There were also interceptions of Liriomyza sativae and Liriomyza trifolii in 2011.

The main question, therefore, is, whether in the absence of these pests, PZ arrangements should be retained or extended? The PZ would place an emphasis on the supply of clean planting material, serving as a mechanism to shift the focus for controlling and eradicating the pest onto suppliers from outside of the UK reducing the risk of the pest being re-introduced. But it would also involve burdens for industry and Government, to maintain pest free status.

In this consultation no specific policy recommendation is proposed. Respondents should consider the information provided and submit their own views on what the future policy should entail. Options for the future:

• Maintain the status quo i.e. a Protected Zone for Liriomyza bryoniae in Northern Ireland and existing restrictions on the introduction and movement of L. huidobrensis and L. trifolii
• Maintain the Northern Ireland Protected Zone for Liriomyza bryoniae and expand the requirement to incorporate a UK wide Protected Zone for L. huidobrensis and L. trifolii
• No PZ for any of the Liriomyza spp. on the basis that detections in imports have in general fallen in recent years possibly as a result of improved control measures in other MS and third countries resulting in a reduced risk of the pest being imported and therefore a reduction in the need for a PZ

The pest is not listed in the Annexes of the EC Plant Health Directive 2000/29/EC and is not recommended for regulation as a quarantine pest by EPPO, nor is it on the EPPO Alert list. It is listed as an A2 quarantine pest of Triticum spp. by the Inter-African Phytosanitary Council, African Union. It has been detected in England in association with fresh apple, citrus, nectarine, peach and plum fruit imported from South Africa. The most significant finding was in February 2011, when several hundred live adult bugs were detected with South African peaches at the Port of Tilbury, Essex. The consignment was destroyed under statutory notice to prevent the introduction of the pest.

It is a serious pest of wheat, oats and barley in South Africa. Attacks by the bug in the drier grain-growing area of the Western Cape Province often make cultivation of these crops uneconomic. However, outdoor establishment in the UK is unlikely because the climates of the Western Cape and the UK are very different and this species is unlikely to survive the prolonged cold and damp conditions of British winters except where they are protected, e.g. in farm buildings. This species has not been observed in protected crops. The poor wintering survival, coupled with low population densities if survival did occur, indicates that any impacts are expected to be very small. Where populations have been able to overwinter and establish on grasses and grain crops in the vicinity, densities are likely to be highest in the warmest and driest areas of eastern England but these are still significantly cooler and wetter than areas of South Africa where it is a damaging pest. Control on cereal crops would probably be relatively straightforward, in the absence of insecticide resistance, although it could involve additional treatments and there is some uncertainty concerning the effectiveness of available products. The key issue for this RA is the climatic suitability of the UK in comparison with areas of South Africa where it is a serious pest. Since this has already been explored, a more detailed UK PRA on this pest is not required. Details of this risk assessment should be passed to EPPO for awareness and to alert southern EPPO countries which may be more at risk.

The pest is not listed in the EC Plant Health Directive and is not recommended for regulation as a quarantine pest by EPPO, nor is it on the EPPO Alert List.

It is likely that M. nitidalis entered the UK in association with tree ferns imported from Australasia. Due to the level of non-native organisms that may be associated with this trade, tree ferns are treated prior to export. Previously, the trade in tree ferns was largely unregulated for 10 years or more and this may have been when this particular pest entered. Some uncertainty exists over the potential economic and environmental impact of the pest on native species. However, there are no records of damage reported in its native habitat. Specialist growers of ferns could also be at a low risk of the moth spreading from tree ferns to other species in a nursery. Overall the environmental and economic impact is expected to be low.

Given that M. nitidalis is already likely to be naturalised, probably having entered on a pathway which has since been regulated, further action and a more detailed PRA are not required.

Until 2011, O. kwansonis was unknown outside Japan and Taiwan. Then, in 2011 it was reported as a pest in the USA (from 15 states in the eastern half of the USA, from Maine in the north to Florida in the south). Evidence suggests that it has been present in the US since at least 2008, but possibly since 2006. This is particularly significant as there is very active development of new Hemerocallis cultivars and European nurseries obtain some of these from nurseries in the USA, creating a potential pathway for the introduction of the pest into Europe. An analysis of UK plants for planting phytosanitary certificates revealed that, in 2010-2011, 223 Hemerocallis plants (recorded as bare-rooted or as bulbs) were imported from the USA. The pests mining and hibernation in the base of leaves makes association with imported plants for planting likely.

Affected plants are disfigured lowering their value.

Following a total of 10 findings of O. kwansonis in the Ljublijana region of Slovenia in 2011/2012 (two private gardens, a public park and a botanical garden) on leaves of imported plants of Hemerocallis species (day lilies), the pest can now be considered as present in the EU. However, measures could be introduced to stop further entry of the pest into the EU or movement within the EU, via the listing of O. kwansonis in Annex IIAII of Directive 2000/29/EC with Annex IVAI and IVAII requirements, requiring plants for planting of Hemerocallis spp. to come from an area free from this pest. Area freedom would be most effective means of preventing entry into the UK because the pest is too cryptic for place of production or consignment freedom with inspection to be effective.

A more detailed PRA is not recommended.

To prevent entry into the UK, listing in Annex IIAII of Directive 2000/29/EC with IVAI and IVAII requirements, requiring the plants to come from an area free from this pest is recommended.

In the UK, P. fletcheri is only known to occur on a single Western cedar tree in London, where it appears to have been present for eight years (the infested tree was imported from Italy in 2004). The pest is however highly cryptic, particularly when the population density is low, and is therefore easily overlooked. The possibility that it occurs elsewhere in the UK cannot be ruled out. Fletcher scale has the potential to naturalise widely in England and Wales, wherever its host plants occur, as it has been breeding outdoors in London for several years and is present in Canada and Scandinavia. The winters of 2009/10 and 2010/11 were the coldest in southern England for decades but the scale survived outdoors. Natural dispersal of the pest is likely to be limited, with distribution of the pest likely to be as a result of movement in trade of infested plants for planting.

There are several closely related species of Parthenolecanium already present in Britain which are controlled by a complex of naturally-occurring parasitic wasps, insect predators and entomopathogenic fungi. P. fletcheri is likely to be controlled, at least partially, by these same natural enemies already present in the UK, so control measures are unlikely to be necessary unless severe infestations occur on individual plants. The population found in Britain was already being controlled to some degree by hymenopteran parasitoids.

Economic impacts are expected to be restricted to a reduction in the aesthetic appearance and therefore market value of ornamental plants although the potential losses are likely to be small.

No Statutory Action

With the information that we currently have available on the scale it is not of sufficient concern to the UK to justify a more detailed assessment. As such a recommendation for no statutory action is proposed.

Pepino mosaic virus (PepMV)

PepMV PRA cover note

The PRA recommends listing under Annex IIAII of the EU Plant Health Directive 200/29/EC with requirements for seeds.

Fera supports the PRA recommendation but also asks respondents for their views on plants for planting. At present statutory action is taken when PepMV is detected in tomato plants for planting but this would not be possible if an Annex IIAII listing was restricted to seeds. Respondents are asked to consider the information at section 3.4.2 of the PRA in considering this issue.

Following a PRA for a Peronospora sp. on sweet basil in 2005, a new species of Peronospora infecting sweet basil plants was described as P. belbahrii. This Rapid Assessment is being done in response to the first finding of P. belbahrii in the UK as well as the first finding on a new host, Agastache spp.

To date there have been seven UK findings of P. belbahrii on Agastache (5) and sweet basil (2) plants in commercial nurseries (UK and European origin), on which statutory action was taken, and two interceptions of P. belbahrii on sweet basil leaves imported from Kenya.

P. belbahrii is considered endemic in Europe and has been found on sweet basil both under protection and outdoors. The pathogen appears to spread internationally with seed. In the UK outbreaks on Agastache, it seems likely that infected plants have been moving in trade within the UK as infected plants at one of the outbreak sites were sourced from another UK nursery and infection has been confirmed in plants grown from seeds sourced within the EU.

For specialist herb growers, severe outbreaks have caused significant crop losses (at least on sweet basil). However, in the UK herb production is relatively small in comparison to major crops and this pathogen has the potential to be managed by non-statutory means.

Phenacoccus peruvianus is native to South America and has been introduced to Europe where it has naturalised widely along the Mediterranean coast of France, Monaco, Spain, southern coast of Portugal, the Balearic Islands, Corsica and Sicily. The pest is not currently known to be established anywhere in the UK, although breeding populations under protection (commercial glasshouses, botanical gardens) have been found on three occasions. Action to eradicate the mealybugs was taken in each case.

If P. peruvianus became established in Britain, the economic impact is likely to be very small, as although it may damage individual bougainvillea plants grown indoors, its host plants are not common in Britain. It is unlikely to have any impact on biodiversity, ecosystems, crops or forestry in the UK. However, there is a degree of uncertainly as it was only described recently (2007) and its full host range, biology and economic importance have not been studied in detail.

No Statutory Action

With the information that we currently have available on the scale it is not of sufficient concern to the UK to justify a more detailed assessment. As such a recommendation for no statutory action is proposed.

There have only been six putative interceptions of P. quercus in the UK to date, all on Holm oak imported from Italy. The UK has a number of native phylloxerid, which have been misdiagnosed as P. quercus and vice-versa, as such it is possible that P. quercus is already established in the UK.

The highest risk areas are restricted to southern England and the economic impact is expected to be small. Natural predators exist for native phylloxerid, which it is expected, would help to control infestations of P. quercus to an acceptable level.

Given that it is not known with any degree of certainty whether or not P. quercus group species are already established in the UK, and that control measures are in any case often unnecessary (as the damage is largely aesthetic) no statutory action is recommended.

Phytophthora austrocedrae.

Consultation letter (PDF 30KB)

Phytophthora pseudosyringae

Consultation outcome

Woodland: mainly beech and oaks but also other tree species including hornbeam, sweet chestnut, rauli etc. Understory bilberry in woodland and possibly heathland.

More rarely nursery stock and gardens.

The rapid assessment was initiated as a result of the first finding of P. pseudosyringae on a new host, Vaccinium myrtillus (bilberry). As part of the official surveys for Phytophthora kernoviae and Phytophthora ramorum in England and Wales, in January 2009, diseased bilberry plants in ancient woodland in Staffordshire, England were sampled and tested positive for P. pseudosyringae. In May 2009, symptomatic plants of V. myrtillus in woodland in the south-west of England (Cornwall) were also found to be infected with this pathogen. These are the first reports of P. pseudosyringae on V. myrtillus. The rapid assessment was conducted to determine the status of the pathogen in the UK, whether or not a full PRA is required, and to determine future action.

Although it was thought that the 2009 findings were the first records of the pathogen in the UK, subsequent investigation has revealed that records date back to at least 2004. The pathogen may even have been present at least as far back as early as 1938 but misidentified as another Phytophthora species, many years before P. pseudosyringae was first described (in 2003). P. pseudosyringae is therefore considered to be established here with no prospect of eradication or official control.

Plum pox Potyvirus (PPV)

PRA cover note

Rhagoletis cingulata (Eastern cherry fruit fly)

PRA Summary

Major hosts:Prunus avium - Sweet/wild cherry; Prunus cerasus - Sour, pie or tart cherry; Prunus salicina - Japanese plum; Pyrus communis - European pear, species from which most orchard cultivars in Europe, USA and Australia are developed

Minor hosts: Prunus serotina - Wild black cherry, normal wild host in USA; Prunus virginiana - Common choke cherry tree; Prunus mahaleb - Mahaleb cherry

Incidental: Other Prunus spp

Rhagoletis cingulata (Eastern cherry fruit fly) is spreading in Europe. It's potential to spread to the UK poses a risk to the cherry industry, but also of concern is the risk posed to international trade, as the UK does not currently have any fruit flies that cause economic damage to orchard grown fruit.

Overall assessment of pest: It is possible for it to enter the UK along the pathways discussed, but unlikely that it would transfer to hosts, find a suitable environment and establish. More information on host and environmental preferences would be required to reduce the level of uncertainty. If it did establish, however, the pest would be difficult to eradicate as it could easily survive in untreated and unmonitored wild host populations. The pest is likely to be detected early in the UK though, due to our lack of other fruit fly pests on cherries with which it may be confused. The area most at risk is the south-east, where conditions are most likely to be favourable and where the largest concentration of hosts (commercial and other) are found.

Stenchaetothrips spinalis was first found in the UK at a commercial nursery in 2002 and that population was at first subjected to statutory control. However, this requirement for statutory control was later removed on the basis that the thrips were restricted to bamboo and unlikely to survive outdoors. This species was subsequently found outdoors on bamboo at a public botanical collection in July 2010. The bamboo was located right up against a wall in a warm, dry, protected, spot, and had been present there since the mid 1990s. However, it is suspected that introduction of the thrips may have occurred in 2008 when two large "architectural" bamboo plants were stationed only a few metres away. The bamboo was also infested with bamboo mites and was cut down to the ground and the stems burnt.

The species is not known to have caused any economic impact in either its area of origin or where it has established elsewhere.

Forestry Commission and Fera pest risk analysts have identified the PPM as a priority pest for evaluation. Until recently it was only found in the Mediterranean region, North Africa and some areas of the Middle East and southern Europe. However, since the 1990s the pest has been moving north through France and is now breeding near Paris. Unsubstantiated reports also state that PPM is found in the USA and Canada. The recent expansion of PPM in France has raised concerns for the UK and in particular for the south coast of England which is climatically similar to areas of northern France where the pest is now known to be established.

At present plants for planting are considered an unlikely potential pathway for introduction into the UK. This assumption is based partly on the low volume of trade in host material and the low level of previous findings. Should either of these variables change then the likelihood would need to be revised accordingly.

The rapid assessment recommendation given the similarity in climate between northern France and the southern coast of England is that a detailed PRA is required to assess the risk of establishment and the associated uncertainties.

In the meantime, statutory action will be taken on findings on a precautionary basis, in response to the potential risk to the south of England. An awareness raising programme will be undertaken to encourage vigilance within the trade and by members of the public.

TMGMV was first reported in the Canary Islands in the wild host Nicotiana glauca and it is thought to be widespread within this host wherever it is distributed, including the USA, Australia, and in the European and African countries of France (including Corsica), Madeira, the Canary Islands and Tunisia. In Germany TMGMV is common in field tobacco (Nicotiana tabacum). There have been reported findings in other hosts on a range of continents in Korea, Taiwan, Venezuela, southern France, Italy, Israel, Tunisia, Panama, and recently in Iran on tomato as well as on more hosts in the USA.

The main pathway on which TMGMV is likely to enter the UK is the movement of infected ornamental host plants from countries where the virus occurs. The UK has found the virus in UK nurseries twice on material on (impatiens - 2007 and osteospermum - 2008) imported from Belgium and Denmark, although there are no records of the virus in these countries. Both outbreaks were eradicated, but there is concern that infected ornamental plants may act as a reservoir for infection of Capsicum and possibly tomato and this initiated a rapid assessment. Subsequently (January 2012) it was agreed that a full UK PRA was required.

Given the limited amount of information currently available and the level of uncertainty regarding the potential damage to tomatoes in the UK, the recommendation of the PRA is that there is sufficient justification for continued action. However in the event of further information on TMGMV becoming available or there being a dramatic increase in the number of outbreaks in ornamentals (or indeed) tomatoes then it will be important to review action being taken.