This Guidance describes a two-phase approach for a fit-for-purpose method for the assessment of plant pest risk in the territory of the EU. Phase one consists of pest categorisation to determine whether the pest has the characteristics of a quarantine pest or those of a regulated non-quarantine pest for the area of the EU. Phase two consists of pest risk assessment, which may be requested by the risk managers following the pest categorisation results. This Guidance provides a template for pest categorisation and describes in detail the use of modelling and expert knowledge elicitation to conduct a pest risk assessment. The Guidance provides support and a framework for assessors to provide quantitative estimates, together with associated uncertainties, regarding the entry, establishment, spread and impact of plant pests in the EU. The Guidance allows the effectiveness of risk reducing options (RROs) to be quantitatively assessed as an integral part of the assessment framework. A list of RROs is provided. A two-tiered approach is proposed for the use of expert knowledge elicitation and modelling. Depending on data and resources available and the needs of risk managers, pest entry, establishment, spread and impact steps may be assessed directly, using weight of evidence and quantitative expert judgement (first tier), or they may be elaborated in substeps using quantitative models (second tier). An example of an application of the first tier approach is provided. Guidance is provided on how to derive models of appropriate complexity to conduct a second tier assessment. Each assessment is operationalised using Monte Carlo simulations that can compare scenarios for relevant factors, e.g. with or without RROs. This document provides guidance on how to compare scenarios to draw conclusions on the magnitude of pest risks and the effectiveness of RROs and on how to communicate assessment results.

Abstract The European Commission requested EFSA to conduct a pest categorisation of Toxoptera citricida (Hemiptera: Aphididae), an oligophagous aphid developing and reproducing parthenogenetically on tender leaf and flower flush of citrus (Rutaceae). T. citricida is a taxonomic entity with reliable methods available for detection and identification. It is regulated in the EU by Council Directive 2000/29/EC where it is listed in Annex IIAI as a harmful organism whose introduction and spread into the EU shall be banned. T. citricida is native to tropical regions of Southeast Asia and has spread to most citrus‐growing areas worldwide, except California and the Mediterranean basin, causing significant damage to citrus as it is the most efficient vector of the Citrus tristeza virus (CTV). T. citricida occurs in Madeira and, with a restricted distribution, in the north‐west of the Iberian Peninsula, mostly on backyard citrus trees. This may have hindered the effectiveness of the official control measures in these areas. There are further phytosanitary measures in place in the EU in order to limit entry via traded commodities. Citrus plants for planting are regulated and are a closed pathway. However, there is uncertainty regarding host status of some non‐rutaceous plants on which this aphid has been recorded and so other plant genera may provide additional pathways. The EFSA Plant Health Panel concludes that the establishment of T. citricida in the main EU citrus growing areas around the Mediterranean would have significant impacts because of its ability to vector CTV. Considering the criteria within the remit of EFSA to assess the status as a potential Union quarantine pest (QP), as a potential protected zone quarantine pest (PZQP) or as a potential regulated non‐quarantine pest (RNQP), T. citricida meets with no uncertainties the criteria assessed by EFSA for consideration as a potential Union QP.

Abstract The Panel on Plant Health performed a pest categorisation of Colletotrichum gossypii, the fungal agent of anthracnose and ramulosis diseases of cotton, for the EU. The identity of the pest is well established and reliable methods exist for its detection/identification. The pest is present in most of the cotton‐growing areas worldwide, including Bulgaria and Romania in the EU. Colletotrichum gossypii is listed as Glomerella gossypii in Annex IIB of Directive 2000/29/EC and is not known to occur in Greece, which is a protected zone (PZ). The only hosts are Gossypium species, with G. hirsutum and G. barbadense being the most susceptible. The pest could potentially enter the PZ on cotton seeds originating in infested third countries or EU infested areas. Entry into PZ by natural means from EU infested areas is possible, although there is uncertainty on the maximum distance the pest can travel by wind or insects. Bolls and unginned cotton are minor pathways of entry. Pest distribution and climate matching suggest that the pest could establish and spread in cotton‐producing areas of northern Greece. In the infested areas, the pest causes damping‐off, leaf/boll spotting, boll rot, witches’ broom symptoms and stunting resulting in yield and quality losses. It affects also the lint and seeds reducing fibres quality and seed germinability. It is expected that its introduction and spread in the EU PZ would impact cotton yield and quality. The agricultural practices and control methods currently applied in Greece would not prevent pest establishment and spread. Colletotrichum gossypii meets all the criteria assessed by EFSA for consideration as potential quarantine pest for the EU PZ of Greece. The criteria for considering C. gossypii as a potential Union regulated non‐quarantine pest are also met since cotton seeds are the main means of spread.

Abstract The Panel on Plant Health performed a pest categorisation of the South African citrus thrips, Scirtothrips aurantii Faure (Thysanoptera: Thripidae), for the European Union (EU). This is a well‐defined and distinguishable species, recognised as a pest of citrus and mangoes in South Africa, which has been cited on more than 70 different plants, including woody and herbaceous species. It feeds exclusively on young actively growing foliage and fruit. S. aurantii is not known to occur in the EU and is listed in Annex IIAI of 2000/29/EC as a harmful organism presenting a risk to EU plant health. The international trade of hosts as either plants for planting or cut flowers provide potential pathways into the EU. However, current EU legislation prohibits the import of citrus plants. Furthermore, measures aimed at the import of plants for planting in a dormant stage (no young foliage or fruits present) with no soil/growing medium attached, decreases the likelihood of the pest entry with such plants. Interceptions have occurred on Eustoma grandiflorum cut flowers. Considering climatic similarities between some of the countries where S. aurantii occurs (South Africa, Australia) and the EU, its thermal biology and host distribution in the EU, S. aurantii has the potential to establish, especially in citrus‐growing regions of the EU. S. aurantii would most probably breed all year long around the Mediterranean and could cause crop losses in citrus, especially oranges. Phytosanitary measures are available to inhibit the introduction of S. aurantii. Considering the criteria within the remit of EFSA to assess its status as a potential Union quarantine pest (QP) or as a potential regulated non‐quarantine pest (RNQP), S. aurantii meets with no uncertainties the criteria assessed by EFSA for consideration as a potential Union QP.

Abstract The Panel on Plant Health performed a pest categorisation of the citrus snow scale, Unaspis citri (Comstock) (Hemiptera: Diaspididae), for the European Union (EU). This is a well‐defined and distinguishable species, native to south‐eastern Asia, which has spread to many tropical and subtropical regions. U. citri can be a pest of citrus and has been cited on over 28 different species in 16 plant families. In the EU, U. citri occurs in the Azores. There is uncertainty as to whether it occurs in continental Portugal. Reports of it occurring in Greece and Spain are likely to be invalid and based on interception records from these countries. An old Italian record is a misidentification. U. citri is listed in Annex IIAI of 2000/29/EC as a harmful organism. The international trade of hosts, as either plants for planting, fruit or cut flowers, provide potential pathways into the EU. However, current EU legislation prohibits the import of citrus plants for planting from third countries. U. citri is mostly confined to coastal humid tropical areas and does not occur in semi‐arid areas that are irrigated. Nevertheless, given that it occurs in the Azores and that there are regional climatic similarities between places where U. citri occurs and climates within the EU, and taking EU host distribution into account, U. citri has the potential to establish in the EU, especially in citrus‐growing regions around the Mediterranean where losses in quality and yield of citrus could occur. Phytosanitary measures are available to inhibit the likelihood of introduction of U. citri. Considering the criteria within the remit of EFSA to assess the status as a potential Union quarantine pest (QP), or as a potential regulated non‐quarantine pest (RNQP), U. citri meets the criteria assessed by EFSA for consideration as a potential Union QP.

Abstract The Panel on Plant Health performed a pest categorisation of the Siberian moth, Dendrolimus sibiricus Tschetverikov (Lepidoptera: Lasiocampidae). D. sibiricus is a well‐defined and distinguishable species, native to Asian Russia and northern regions of Kazakhstan, Mongolia, China and North Korea, and recognised as a severe pest of Pinaceae conifers, mainly larch (Larix spp.), fir (Abies spp.), spruce (Picea spp.), five‐needle pines (Pinus spp.). It has also a potential to develop on non‐native Pinaceae: Cedrus, Pseudotsuga, Tsuga. It defoliates healthy trees and kills thousands of hectares of forests. It is absent from the EU and is listed as a quarantine pest in Annex IAI of Directive 2000/29/EC. Plants for planting, branches of conifers and non‐squared wood from its distribution range are considered as pathways for the pest, which can also disperse by flight over tens of kilometres. The females produce sex pheromones. Adults do not feed and can survive for about 2 weeks. One female lays up to 400 eggs, attaching them to needles. One generation usually develops in 2–3 years, with larvae passing winter diapause and some undergoing facultative summer diapause. Exceptionally, 1‐year generations may occur if the number of degree‐days above 10°C is higher than 2,200. Larvae feed on needles through 5–6 instars and pupate in a cocoon on tree branches. Mature larvae have urticating setae on thoracic segments that protect them from enemies and may cause allergic reactions in humans and animals. The contradictory studies regarding the climatic requirements of D. sibiricus make the issue of its establishment in most of the EU territory uncertain, although its host trees are widely present. All criteria for considering D. sibiricus as a potential quarantine pest are met. The species is presently absent from the EU, and thus, the criteria for consideration as a potential regulated non‐quarantine pest are not met.

The Plant Health Panelreviewed the paper by Guarnaccia etal. (2017) and compared their findings with previous predictions on the establishment of Phyllostictacitricarpa. Four species of Phyllosticta were found by Guarnaccia etal. (2017) in Europe. P.citricarpa and P.capitalensis are well-defined species, with P.citricarpa recorded for the first time in Europe, confirming predictions by Magarey etal. (2017) and EFSA (2008, 2014, 2016) that P.citricarpa can establish in some European citrus-growing regions. Two new species P.paracitricarpa and P.paracapitalensis were also described, with P.paracitricarpa (found only in Greece) shown to be pathogenic on sweet orange fruits. Genotyping of the P.citricarpa isolates suggests at least two independent introductions, with the population in Portugal being different from that present in Malta and Italy. P.citricarpa and P.paracitricarpa were isolated only from leaf litter in backyards. However, since P.citricarpa does not infect or colonise dead leaves, the pathogen must have infected the above living leaves in citrus trees nearby. Guarnaccia etal. (2017) considered introduction to be a consequence of P.citricarpa having long been present or of illegal movement of planting material. In the Panel's view, the fruit pathway would be an equally or more likely origin. The authors did not report how surveys for citrus black spot (CBS) disease were carried out, therefore their claim that there was no CBS disease even where the pathogen was present is not supported by the results presented. From previous simulations, the locations where Guarnaccia etal. (2017) found P.citricarpa or P.paracitricarpa were conducive for P.citricarpa establishment, with number of simulated infection events by pycnidiospores comparable to sites of CBS occurrence outside Europe. Preliminary surveys by National Plant Protection Organisations (NPPOs) have not confirmed so far the findings by Guarnaccia etal. (2017) but monitoring is still ongoing. (c) 2018 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.

The Panelon Plant Health performed a pest categorisation of the non-EU Pissodes spp. (Coleoptera: Curculionidae). They constitute a well-defined taxon, with non-EU species distributed in the USA, Canada, Mexico, Guatemala, El Salvador, China, Japan, Korea, Russia and South Africa, some of which are recognised as severe pests of conifers, mainly Pinus spp. and Picea spp., or vector pathogens. The immature stages either live in the phloem and cambium of healthy, weakened or dead trees, or in the terminal shoots of living trees. They are listed as quarantine pests in Annex IAI of Directive 2000/29/EC. Plants for planting, branches of conifers and non-squared wood are considered as pathways. The pest can also disperse by hitchhiking, and fly over kilometres. The adults are long-lived (up to 4 years). They feed by puncturing the bark of stems or shoots. Females lay eggs in chewed-out cavities in the bark. The life cycle varies with species and local climatic conditions. At the end of the larval stage, the larva excavates a pupal cell between the sapwood and the bark, in the sapwood or in terminal shoots. Pissodes spp. overwinter as adults in the litter or as larvae or teneral adults in the galleries or pupal cells. The current geographic range of the non-European Pissodes spp. suggests that many of them may establish in the EU territory, where their hosts are widely present. We list some species which, if introduced to the EU, would most probably have an economic impact on plantations or may interfere with forest ecosystem processes although they are mainly abundant and damaging in intensively managed monocultures. All criteria for considering those non-EU Pissodes spp. as potential quarantine pests are met. The criteria for considering them as non-regulated quarantine pests are not met because they are absent from the EU territory. (C) 2018 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.

Abstract Following a request from the European Commission, the EFSA Plant Health Panel updated its pest categorisation of Xylella fastidiosa, previously delivered as part of the pest risk assessment published in 2015. X. fastidiosa is a Gram‐negative bacterium, responsible for various plant diseases, including Pierce's disease, phony peach disease, citrus variegated chlorosis, olive quick decline syndrome, almond leaf scorch and various other leaf scorch diseases. The pathogen is endemic in the Americas and is present in Iran. In the EU, it is reported in southern Apulia in Italy, on the island of Corsica and in the Provence‐Alpes‐Côte d'Azur region in France, as well as in the Autonomous region of Madrid, the province of Alicante and the Balearic Islands in Spain. The reported status is ‘transient, under eradication’, except for the Balearic Islands, Corsica and southern of Apulia, where the status is ‘present with a restricted distribution, under containment’. The pathogen is regulated under Council Directive 2000/29/EC and through emergency measures under Decision (EU) 2015/789 (as amended Decision (EU) 2017/2352). The pest could enter the EU via host plants for planting and via infectious insect vectors. The host range includes hundreds of host species listed in the EFSA host plant database. In the EU, host plants are widely distributed and climatic conditions are favourable for its establishment. X. fastidiosa can spread by movement of host plants for planting and infectious insect vectors. X. fastidiosa is known to cause severe direct damage to major crops including almonds, citrus, grapevines, olives, stone fruits and also forest trees, landscape and ornamental trees, with high impacts. The criteria assessed by the Panel for consideration as a potential Union quarantine pest are met (the pathogen is present in the EU, but it has a restricted distribution and is under official control). X. fastidiosa is not considered as a regulated non‐quarantine pest (RNQP) as the pathogen may spread also via insect vector transmission.

The Panelon Plant Health performed a pest categorisation of Teciasolanivora (Lepidoptera: Gelechiidae) the Guatemalan potato tuber moth, for the EU. T.solanivora is a well-defined species which feeds exclusively on Solanumtuberosum. It was first described from Costa Rica in 1973 and has spread through Central America and into northern South America via trade of seed potatoes. It has also spread to Mexico and the Canary Islands and most recently to mainland Spain where it is under official control in Galicia and Asturias. Potatoes in the field and storage can be attacked. Some authors regard T.solanivora as the most important insect pest of potatoes globally. T.solanivora is currently regulated by Council Directive 2000/29/EC, listed in Annex II/AI as Scrobipalpopsissolanivora. Larvae feed and develop within potato tubers; infested tubers therefore provide a pathway for pest introduction and spread, as does the soil accompanying potato tubers if it is infested with eggs or pupae. As evidenced by the ongoing outbreaks in Spain, the EU has suitable conditions for the development and potential establishment of T.solanivora. The pest could spread within the EU via movement of infested tubers; adults can fly and disperse locally. Larval feeding destroys tubers in the field and in storage. In the warmer southern EU, where the development would be fastest, yield losses would be expected in potatoes. Measures are available to inhibit entry via traded commodities (e.g. prohibition on the introduction of S.tuberosum). T.solanivora satisfies all of the criteria assessed by EFSA to satisfy the definition of a Union quarantine pest. It does not satisfy EU regulated non-quarantine pest (RNQP) status because it is under official control. There are uncertainties over the effectiveness of preventing illegal imports via passenger baggage and the magnitude of potential impacts in the cool EU climate. (c) 2018 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.

Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of the seed-borne bacterium Curtobacterium flaccumfaciens pv. flaccumfaciens. The pest is regulated in Council Directive 2000/29/EC (Annex IIB) as a harmful organism whose introduction into, and spread within, the protected zones (PZ) of Greece, Portugal and Spain shall be banned if present on seeds of Phaseolus vulgaris and of Dolichos. The bacterium is widely distributed outside the EU and causes a systemic vascular disease (bacterial wilt of bean) as well as bacterial tan spot disease on soybean. The pest was sporadically recorded in several EU Member States in the past, but is currently not known to occur in the EU. The identity of the bacterium is well established and identification methods are available. The major host is common bean (Phaseolus vulgaris), but other crops and weeds are, or may be, hosts or play a role as reservoirs, with uncertainties. Seed transmission remains uncertain for minor and alternative host species. The main pathway for entry is seed. The role of other pathways (e.g. irrigation water and infected residues) is uncertain. Should the bacterium enter the EU (including the PZ), it may establish, spread and have an impact on its host crops. The use of healthy seeds is the most effective control measure. Curtobacterium flaccumfaciens pv. flaccumfaciens fits all the criteria assessed by EFSA to be regarded as a Union quarantine pest.

Following a request from the European Commission, the EFSA Plant Health (PLH) Panel performed a pest categorisation of Bretziella fagacearum, a well-defined and distinguishable fungal species of the family Ceratocystidaceae. The species was moved from the genus Ceratocystis to a new genus Bretziella following phylogenetic analysis of the species and its close relatives. The former species name Ceratocystis fagacearum is used in the Council Directive 2000/29/EC. The pathogen is regulated in Annex IAI as a harmful organism whose introduction into the EU is banned. B. fagacearum is only reported from the USA, where it causes a wilt disease on Quercus spp. Other hosts are reported based on inoculation trials, although Chinese chestnut (Castanea mollissima) is reported to be naturally infected. No North American oak species has been found to be immune to the disease. The European oak species Quercus robur, Quercus petraea and Quercus pubescens were found to be susceptible in inoculation experiments. The pest could enter the EU via wood (with and without bark, including wood packaging material), plants for planting and cut branches. Hosts and favourable climatic conditions are common in the EU, thus facilitating establishment. The pest would be able to spread following establishment by means of root grafts, insect vectors and movement of wood, plants for planting and other means. The pest introduction would have impacts in woodland and plantations, as oak wilt disease is often lethal in a short period of time. Wood treatment (debarking, kiln drying, fumigation), prompt removal of affected trees and creating root-free zones between affected and healthy stands are available control measures. The main knowledge gaps concern (i) the survival of the fungus in wood during transport and the association with propagation material, (ii) the presence of suitable vectors in Europe and (iii) the relative susceptibility of the oak species native to Europe under natural conditions. The criteria assessed by the Panel for consideration as a potential quarantine pest are met. For regulated non-quarantine pests, the criterion on the pest presence in the EU is not met.

The Panelon Plant Health performed a pest categorisation of nematodes belonging to the genus Hirschmanniella (Nematoda: Pratylenchidae). Twenty-nine species in this genus have been considered of which five species are present in the EU (Hirschmanniellabehningi, Hirschmanniellagracilis, Hirschmanniellahalophila, Hirschmanniellaloofi and Hirschmanniellazostericola). The whole genus except H.gracilis is regulated by Council Directive2000/29/EC (Annex IAI). Hirschmanniella species are root endoparasites uniquely adapted to aquatic environments. Most species are reported from tropical regions. Monocotyledons including aquatic plants are main hosts and some Hirschmanniella species are important pests of rice. Plants for planting are potential pathways for entry. Hirschmanniella species are frequently intercepted on imported aquarium plants. Measures are available to avoid entry. Environmental conditions in greenhouses and potentially in rice production areas of the EU are suitable for establishment. The nematode may be spread with irrigation, tools or plants for planting. Hirschmanniella species were categorised into four groups. The first group includes species reported as pests of crop plants; those satisfy all the criteria that are within the remit of EFSA to assess to be regarded as Union quarantine pests. The second group includes species that are not reported to cause economic damage to crop plants; those species do not satisfy all the criteria to be regarded as Union quarantine pests. Uncertainty exists whether species in this group can cause damage once introduced into the EU. The third group includes species that are known to be present in the EU and do not cause damage; they do not satisfy the criteria to be regarded as Union quarantine pests or regulated non-quarantine pests. The fourth group consists of H.gracilis only. This worldwide occurring species is present in the EU where it does not cause economic damage. It does not satisfy all the criteria to be regarded as a Union quarantine pest. (C) 2018 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.

The Panelon Plant Health performed a pest categorisation of Listronotus bonariensis (Coleoptera: Curculionidae), the Argentine stem weevil, for the EU. L.bonariensis is a well-defined species, recognised as a serious pest of pasture grasses, especially Lolium spp. and Poa annua, in New Zealand, and a rare pest of cereals in Argentina, Brazil and New Zealand. Larvae feed within the tillers and stems of grasses; adults can cut emerging cotyledons although they usually graze on leaves. Larval damage is most serious. Larval feeding causes a reduction in pasture quality that impacts on the production of grazing animals. L.bonariensis is not known to occur in the EU and is listed in Annex IIAI of Council Directive 2000/29/EC. L.bonariensis established in New Zealand via imported grass seeds and has been intercepted on grass seeds entering the EU. Considering the climatic similarities of the regions where the pest occurs and the very great extent to which hosts are grown across the EU, L.bonariensis has the potential to establish within the EU with two or three generations possible per year. Impacts could occur in grassland pastures and perhaps occasionally in cereals. In New Zealand, endophytic fungi occurring on potential hosts deter L.bonariensis from ovipositing on leaves and are toxic to larvae. Whether endophytic fungi on grasses in Europe could provide some resistance to L.bonariensis is uncertain. Phytosanitary measures are available to reduce the likelihood of introduction of this weevil. L.bonariensis fits all of the criteria assessed by EFSA to satisfy the definition of a Union quarantine pest. L. bonariensis does not meet the criterion of occurring in the EU territory for it to be regarded as a Union regulated non-quarantine pest. (C) 2018 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.

Following a request from the European Commission, the EFSA Plant Health Panel performed a pest categorisation of Sphaerulina musiva, a well-defined and distinguishable fungal species of the family Mycosphaerellaceae. Following a recent phylogenetic analysis of the genus Septoria and other closely related genera, a new name (S. musiva) was introduced for the species. The former species name Mycosphaerella populorum is used in the Council Directive 2000/29/EC. The pathogen is regulated in Annex IAI as a harmful organism whose introduction into the EU is banned. S. musiva is reported from North and South America and not known to occur in the EU. S. musiva causes Septoria leaf spots and cankers of poplar (Populus spp.). Of the poplars native to Europe, Populus nigra is reported as susceptible and Populus tremula as susceptible when planted in North America. The hybrid Populus x canadensis (arising from a cross of P. nigra and the North American Populus deltoides), widely grown in the EU, is also susceptible. The pest could enter the EU on plants for planting, cut branches, isolated bark and wood with and without bark. S. musiva could establish in the EU, as hosts are common and favourable climatic conditions are widespread, and could spread following establishment by natural dispersal and movement of infected plants for planting, cut branches, isolated bark and wood with or without bark. The pest introduction would have impacts in woodlands, plantations and nurseries. The pathogen is considered the most serious disease affecting hybrid poplar production in North America. Selection, breeding and planting of resistant species and clones are the main methods used to control the damage caused by the pathogen. There is some uncertainty on the geographical distribution of the pest in the Caucasus, the Crimean Peninsula and South America and on the level of susceptibility among Populus species native to Europe as well as Salix spp. The criteria assessed by the Panel for consideration as a potential quarantine pest are met. For regulated non-quarantine pests, the criterion on the pest presence in the EU is not met.

Following a request from the European Commission, the EFSA Plant Health Panel performed a pest categorisation of Pantoea stewartii subsp. stewartii (hereafter P. s. subsp. stewartii). P. s. subsp. stewartii is a Gram-negative bacterium that causes Stewart's vascular wilt and leaf blight of sweet corn and maize, a disease responsible for serious crop losses throughout the world. The bacterium is endemic to the USA and is now present in Africa, North, Central and South America, Asia and Ukraine. In the EU, it is reported from Italy with a restricted distribution and under eradication. The bacterium is regulated according to Council Directive 2000/29/EC (Annex IIAI) as a harmful organism whose introduction and spread in the EU is banned on seeds of Zea mays. Other reported potential host plants include various species of the family Poaceae, including weeds, rice (Oryza sativa), oat (Averta sativa) and common wheat (Triticum aestivum), as well as jackfruit (Artocarpus heterophyllus), the ornamental Dracaena sanderiana and the palm Badris gasipaes, but there is uncertainty about whether these are hosts of P. s. subsp. stewartii or of the other subspecies. The pest could enter the EU via host plants for planting (including seed) and via insect vectors from neighbouring countries. Host plants are widely distributed and climatic conditions are conducive in the EU. P. s. subsp. stewartii could spread by movement of host plants for planting (including seeds) and insect vectors. Impacts could occur on maize and rice. Methods to certify pest freedom of maize seeds are available. The main knowledge gaps concern the availability of vectors in the EU, the level of susceptibility of the maize cultivars grown in the EU, the virulence of strains in recent outbreaks, and the host range of the bacterium. The criteria assessed by the Panel for consideration as a potential quarantine pest are met. (C) 2018 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.

Following a request from the European Commission, the EFSA Plant Health (PLH) Panelperformed a pest categorisation of Anisogramma anomala, a well-defined and distinguishable fungal species of the family Valsaceae. The pathogen is regulated in Annex IIAI of Council Directive 2000/29/EC as a harmful organism whose introduction into the EU is banned on plants of Corylus L., intended for planting, other than seeds, originating in Canada and the USA. The fungus is native to eastern North America and causes eastern filbert blight on cultivated hazel, Corylus avellana, as well as on wild hazel (Corylus spp.). In the 1960s, the disease spread on infected plant material to Oregon, where it then threatened US hazelnut production in the Willamette Valley. The pest could enter the EU via plants for planting. Hosts and favourable climatic conditions are common in the EU, thus facilitating establishment. The pest would be able to spread following establishment through infected plants for planting and ascospore dispersal. A. anomala leads to canopy and yield loss and can cause death of Corylus trees. Should the pathogen be introduced into the EU, impacts can be expected not just on hazel as a crop and as an ornamental but also in coppices and woodlands, where Corylus species provide an important habitat. In Oregon, scouting for cankers, therapeutic pruning and copious fungicide applications are reported to be necessary (but costly measures) to continue hazelnut production in the presence of the disease. Breeding for resistance led to the selection of resistant cultivars. The main knowledge gaps concern (i) the role of deadwood and cut branches as potential entry pathways and means of spread and (ii) the susceptibility of C. avellana cultivars and of Corylus spp. in the wild in the EU. The criteria assessed by the Panelfor consideration as a potential quarantine pest are met. For regulated non-quarantine pests, the criterion on the pest presence in the EU is not met. (c) 2018 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.

Abstract The Panel on Plant Health performed a pest categorisation of the fungus Apiosporina morbosa, the causal agent of black knot, for the EU. The identity of the pest is well established and reliable methods exist for its detection/identification. The pest is listed in Annex IIAI of Directive 2000/29/EC and is not known to occur in the EU. Apiosporina morbosa is present in Alaska, Canada, Mexico and the continental states of the USA. The major hosts of A. morbosa are Prunus domestica and Prunus cerasus; the host status of other Prunus species and hybrids is uncertain because of contradictory reports or lack of information. The pest could potentially enter the EU on host plants for planting and plant parts originating in infested third countries. Wood of Prunus spp. is also a pathway of entry, but of minor importance. The current pest distribution and climate matching suggest that the pest could establish and spread in the EU wherever the hosts are grown. In the infested areas, the pest causes girdling of twigs and occasionally of larger branches, whereas trees with multiple infections loose vigour, bloom poorly, and become unproductive, stunted and susceptible to winter injury and infection by other pathogens. The presence of black knots makes trees unsuitable for timber production. It is expected that the pest introduction and spread in the EU would impact host production. Uncertainty exists on whether the agricultural practices and chemical control methods applied in the EU could prevent the establishment and spread of A. morbosa. A. morbosa meets all the criteria assessed by EFSA for consideration as potential Union quarantine pest. As the pest is not known to occur in the EU, this criterion to consider it as Union regulated non‐quarantine pest is not met.

The Panelon Plant health performed a pest categorisation of the Australian Eucalyptus snout-beetle Gonipterusscutellatus (Coleoptera: Curculionidae), for the EU. G.scutellatus should be referred as the G.scutellatus species complex because it includes several cryptic species. A complete nomenclature of the species present in the EU is still pending. It is a quarantine pest listed in Annex IIB of Council Directive 2000/29/EC. Protected zones are in place in Greece and Portugal (Azores). In the EU, it has been found in Italy, France, Spain and Portugal. It only consumes Eucalyptus species leaves. The main pathways of spread are the trade of Eucalyptus timber, hitchhiking in various commodities, trade of apple fruit as well as of plants for planting or plant parts. Spread by flight is also possible. The climate of the EU protected zones is similar to that of the Member States (MS) where the G.scutellatus complex is established, and the pest's main host plants are present. The damaged trees suffer die-back and the development of epicormics shoots. Severe attacks may provoke massive amounts of tree death. Biological control by using the egg parasitoid wasp Anaphesnitens is the most effective control measure. Some species within the G.scutellatus complex are not yet present in the EU (including G.scutellatus sensu stricto) and might therefore be considered as potential union quarantine pests for the EU territory. At least two species within the G.scutellatus complex (most likely G.platensis and Gonipterus species no. 2) meet the criteria assessed by EFSA for consideration as potential protected zone quarantine pests for the territory of the protected zones: Greece and Portugal (Azores). The criteria for considering the G.scutellatus complex as a potential regulated non-quarantine pest for the EU are not met since plants for planting are not the main pathway. (c) 2018 European Food Safety Authority. EFSA Journal published by John Wiley and Sons Ltd on behalf of European Food Safety Authority.

Abstract Following a request from the European Commission, the EFSA Panel on Plant Health performed a pest categorisation of Coniferiporia sulphurascens and Coniferiporia weirii, two well‐defined and distinguishable fungal species of the family Hymenochaetaceae. The pathogens are regulated in Council Directive 2000/29/EC (Annex IAI, under the previous name Inonotus weirii for both species) as a harmful organism whose introduction into the EU is banned. The two pathogens are native to North America, where C. sulphurascens causes laminated root rot primarily in Douglas fir (Pseudotsuga menziesii) and grand fir (Abies grandis), while C. weirii causes cedar laminated root and butt rot mainly in cedars (Thuja plicata and Cupressus nootkatensis). C. weirii has been reported from Japan and China, and C. sulphurascens from China, Russia and Turkey. Neither species has been reported from the EU. C. sulphurascens may infect all conifers, while C. weirii is reported to mainly cause disease in tree species of Thuja spp. and Cupressus spp. The two pathogens could enter the EU mainly via wood with bark, isolated bark and plants for planting (including artificially dwarfed plants) of Pinaceae and Cupressaceae. Both fungi could establish in the EU, as hosts are present and climatic conditions are favourable. The two pathogens would be able to spread following establishment by the pathways mentioned for entry and also by dissemination of basidiospores and root contact with infected root/wood. Should the pathogen be introduced in the EU, impacts can be expected on coniferous woodlands, plantations and ornamental trees, thus leading to reduced tree growth and ecosystem service provision. The key uncertainties concern (i) the distribution of the two pathogens in Asia, (ii) the level of susceptibility of conifers native to Europe and (iii) the role of plants for planting as a pathway of entry and spread. For both pathogens, the criteria assessed by the Panel for consideration as a potential quarantine pest are met. As the two pests are not present in the EU, not all the criteria for consideration as regulated non‐quarantine pests are met.