RMD-22-02: Pest risk management decision for the regulation of Cydalima perspectalis in Canada

Effective date: November 23, 2022

Preface

As described by the International Plant Protection Convention (IPPC), Pest Risk Analysis (PRA) includes 3 stages: initiation, pest risk assessment and pest risk management.

Initiating the PRA process involves identifying pests and pathways of concern and defining the PRA area. Pest risk assessment provides the scientific basis for the overall management of risk. Pest risk management is the process of identifying, evaluating and selecting potential mitigation measures which may be applied to reduce the identified pest risk to acceptable levels.

This Risk Management Document (RMD) includes a summary of the findings of a pest risk assessment and records the pest risk management process for the identified issue. It is consistent with the principles, terminology and guidelines provided in the IPPC standards for pest risk analysis available at the International Plant Protection Convention website.

Executive summary

Cydalima perspectalis, box tree moth (BTM) is a serious pest of Buxus spp. (boxwood), a woody ornamental plant that, although not native to North America, represents an estimated annual value of $40 million to the Canadian nursery sector.

In November 2018, the Canadian Food Inspection Agency (CFIA) confirmed the presence of C. perspectalis in an urban neighbourhood in Greater Toronto Area. This was the first confirmed report of this pest in North America. In May 2021, following the first detection of the pest in a nursery facility in Ontario and a subsequent related interception of the pest in the United States (U.S.), the U.S. Department of Agriculture-Animal and Plant Health Inspection Service (USDA-APHIS) published a Federal Order prohibiting the importation of plants for planting of Buxus spp., Euonymus spp., and Ilex spp. from Canada to prevent the introduction of this pest into the U.S. via the plants for planting pathway. To date, C. perspectalis has only been detected in southwestern Ontario.

This document presents 3 risk management options that were considered in 2022 and the CFIA's final decision for managing the pest risk posed by C. perspectalis in Canada. These options were published for consultation in August 2022.

All respondents were in favour of regulation of the pest and the majority supported the CFIA's recommended option to add C. perspectalis on the List of Pests Regulated by Canada, create a regulated area for all of Ontario, and apply phytosanitary risk mitigation measures to the importation and domestic movement of Buxus spp. plants for planting. These measures are intended to protect Canada's economy by preventing the spread of C. perspectalis to non-infested areas of Canada. Specific domestic and import requirements will be available to the public through the CFIA website and the CFIA's Automated Import Reference System (AIRS).

Purpose

The purpose of this document is to communicate CFIA's decision for managing the risk of Cydalima perspectalis, box tree moth (BTM) in Canada and the pest risk management options that were considered.

Scope

This document includes:

a summary of CFIA's assessment of risks posed by C. perspectalis
the risk management options considered, and
CFIA's decision and next steps for mitigating the risk of C. perspectalis in Canada

Information pertaining to import requirements for Buxus spp. plants or plant products can be obtained from the Automated Import Reference System.

Definitions, abbreviations and acronyms

Definitions of terms used in this document can be found in the International Standard for Phytosanitary Measures 5: Glossary of phytosanitary terms or the Plant Health Glossary of Terms.

Background

Native to Japan, Korea, and China, box tree moth (BTM), Cydalima perspectalis (Walker), is an invasive pest causing severe damage to boxwood, Buxus spp., in Europe (Maruyama and Shinkaji 1987; Nacambo et al. 2014; Park 2008; Wan et al. 2014; Wang 1980). C. perspectalis was first detected in Europe in 2007, where it was first observed in Germany (Billen, 2007) and the Netherlands (van der Straten and Muus, 2009). Establishment likely occurred after multiple accidental introductions via shipments of ornamental box trees from Asia (van der Straten and Muus, 2009). In the short time frame since its establishment, C. perspectalis has continued to spread into new areas and is now found in up to 30 European countries (Bella 2013; Nacambo et al., 2014; CABI 2020; Strachinis et al. 2015). This spread has been aided by the free movement of live plants in the European Union and the presence of the 2 native species of boxwood (B. sempervirens and B. balearica)in the natural environment in Europe (Brua 2013; Leuthardt et al. 2010; Matošević 2013).

Cydalima perspectalis has a narrow host range, preferring boxwood (Buxus spp.). Boxwoods are planted as ornamentals and typically used for edging, as hedges, and/or clipped into different shapes to make topiaries. When infested, the plants are disfigured by the loss of leaves, webbing spun by the larvae, as well as larval excrement. Larvae feed mostly on leaves but may also attack the bark. Boxwood plants are not native to Canada and there are no natural stands, thus making it less significant as a potential environmental threat in Canada. However, Buxus spp. are widely distributed in North American nurseries, gardens, and parks as an important ornamental shrub and prior to 2021, it was a common nursery plant exported to the U.S. Based on a survey conducted in 2019 by Canadian Nursery Landscape Association (CNLA), annual value of boxwood in production (plants sold in 1 year and plants in the field) was $40M, with annual sales by Canadian growers estimated at $15 million annually.

In October 2018, the CFIA was notified of a community scientist report of a detection of C. perspectalis in an urban Toronto neighbourhood and in November 2018, the CFIA confirmed its presence in the area (iNaturalist, 2018; CFIA, 2018). This was the first confirmed report of this pest in North America. In April 2021, the CFIA confirmed the first detection of C. perspectalis at a nursery facility in St. Catharines, Ontario, and the collaborative monitoring program was expanded within Ontario and monitoring was initiated in British Columbia, Quebec, and Nova Scotia. Subsequently, C. perspectalis was detected at facilities in the U.S. that received Buxus spp. plants from the Canadian facility. In May 2021, the USDA-APHIS published Federal Order DA-2021-11 to prohibit the importation of plants of Buxus spp., Euonymus spp., and Ilex spp. from Canada (USDA-APHIS 2021). In October 2021, the Canadian Nursery Landscape Association (CNLA) submitted a letter to the CFIA requesting the regulation of C. perspectalis for all 3 genera of hosts for which export restrictions are currently in place: Buxus spp., Euonymus spp. and Ilex spp.

Euonymus spp. and Ilex spp. were reportedly included in the USDA-APHIS federal order as suspect C. perspectalis hosts, although no detections of this pest have been reported on these taxa in Canada. To date, C. perspectalis has only been detected in Canada on Buxus spp. plants and only in southwestern Ontario. Detections in Ontario in 2021 have been confirmed in: Greater Toronto Area, Cookstown, Georgetown, Milton, Mississauga, Burlington, Hamilton, Waterloo, Grimsby, Vineland, St. Catharines, Niagara-on-the-Lake and North Pelham (figures 1 and 2). During the 2022 survey season more detections are expected and 2022 reports in LaSalle and Tecumseh, Ontario, in the far south western region of the province have been confirmed. To encourage early detection, the CFIA and its partners have an active social media campaign to engage residents in high-risk areas. When C. perspectalis is confirmed in an area, educational information is distributed, and homeowners are encouraged to treat the pest or remove Buxus spp. and replace them with a non-host shrub.

Figure 1 - Box tree moth 2021 survey results for Ontario. Description follows. — Figure 1 – Box tree moth 2021 survey results for Ontario

Figure 2 - Box tree moth 2021 survey results for Canada (BC, ON, QC, NS). Description follows. — Figure 2 – Box tree moth 2021 survey results for Canada (BC, ON, QC, NS)

Pest risk assessment summary

Pest biology

Geographical location, larval food source, as well as temperature have significant impacts on the biology of C. perspectalis with respect to adult longevity and fecundity, larval developmental time, diapause, number of generations in a year, etc.

Eggs are laid on the underside of host leaves, usually in a cluster of about 10 to 20 eggs (Kenis et al. 2013; Salisbury et al. 2012). The eggs hatch in about 3 days and young larvae feed on the underside of the leaves. The larvae produce webbing on the leaves which helps to shield them from predators. Larvae take about 2 weeks to mature and pupate. Pupae take about 2 weeks to transform from caterpillar into moth (Strachinis et al. 2012; van der Straten and Muus 2009).

Depending on a number of biological factors such as temperature and humidity, C. perspectalis can have several generations per year (Maruyama and Shinkaji, 1987). In 2021, in Ontario, 2 generations of adult moths (peaking around the last week of June/first week of July and again around the last week of August/first week of September) were observed, in contrast to the 3 to 5 generations reported in Europe. In Canada, larvae of the first generation were observed from April to early June, with the first pupa observed in late May. Adult activity began during the second week of June. The second generation of larvae were observed from late June to mid-August. Pupae were found from late July to mid-September.

Cydalima perspectalis overwinters in the larval stage in a silken cocoon spun between host leaves. Adult moths live for about 2 weeks and can fly up to 10 km per year (Brua 2013; Leuthardt et al. 2010; Matošević 2013). During the day, they can be found resting on host plants or on other surrounding plants. Larvae representing the overwintering population in Ontario in 2021 were found actively feeding on Buxus spp. plants from late August to mid-October. Overwintering structures were observed beginning in July.

Damage to boxwood plants is caused by the larvae feeding on the leaves and sometimes on the bark. Boxwood trees can survive being attacked by C. perspectalis provided that the larvae do not eat the bark of the main stems. Younger larvae feed by eating the lower surfaces of the leaves, leaving the upper epidermis intact. Older larvae feed inside a pale white tent of webbing that they have spun for protection and skeletonize the leaves, leaving only the midribs and outer margin intact. Signs of an infestation include: webbing, green pellet shaped frass, cast skins, head capsules, and chewed leaves. Boxwood plants can be infested with all life stages of the C. perspectalis (Nacambo et al., 2014). Unlike the severe damage reported in Europe, most of the boxwood plants observed to be infested with C. perspectalis in Canada sustained only minor to moderate damage in 2021. However, some unmanaged hedges were reported to be completely defoliated by C. perspectalis feeding occurring over approximately 2 years.

Given that the pest has only been reported in Ontario since 2018, there is still limited information on the behaviour and possible impacts of C. perspectalis in North America. Trapping and scouting activities continue to provide data on the phenology and biology of C. perspectalis in Ontario.

Host plants for C. perspectalis

Cydalima perspectalis is primarily a pest of Buxus plant species (Family Buxaceae) (van der Straten and Muus 2009). In Europe, Buxus spp. recorded as hosts of this moth are:

Buxus balearica (Balearic boxwood)
Buxus bodinieri
Buxus harlandii (Harland boxwood)
Buxus megistophylla
Buxus microphylla (Little-leaf box)
Buxus rugulosa
Buxus sempervirens (Common boxwood)
Buxus sinica (Chinese box)

1 species of boxwood, Buxus vahlii, is native to Puerto Rico and the U.S. Virgin Islands (van Kretschmar 2017). Currently, Canadian nurseries propagate their boxwood from on-farm stock as a recommended best practice for the prevention of Cylindrocladium buxicola (boxwood blight). Some Canadian nurseries will purchase finished boxwood plants from US suppliers for re-sale if stock is in short supply domestically. Boxwoods were originally brought to North America as nursery stock from Europe and Asia, bred, and sold to homeowners. Thus, they are primarily found in urban areas, where they are planted around houses and in small gardens. There are no natural stands of boxwood in Canada unlike the situation in Europe (CFIA 2011).

In Asia, C. perspectalis is also a pest of Buxus spp., although some authors note plant species other than Buxus as hosts in Asia (Wang 2008, Korycinska and Eyre 2011): Euonymus alata (Winged spindle) and E. japonicus (Japanese spindle tree, family Celastraceae), Ilex purpurea (Purple-leaved holly, family Aquifoliaceae), Murraya paniculata (Orange jasmine, family Rutaceae).

It should be noted that Murraya plant species are absent in Canada because of their tropical origin. This species is not expected to survive in the Canadian environment (CFIA 2017, 2019).

Euonymus alatus is a deciduous shrub in the Celastraceae family. The leaves of this species turn bright red or reddish purple in the fall and are shed from the bush, revealing the corky branches. This makes the plant unsuitable and unattractive to hibernating C. perspectalis larvae. Brua (2013) reported that Euonymus plants are not suitable hosts for C. perspectalis. In this study, C. perspectalis was reported to cause significant damage to the leaves of 6 Buxus spp., however there was no damage to the leaves of E. europaeus and E. japonicus and just an insignificant amount of damage to the leaves of E. alatus. (Details on how these results were obtained were not provided.). In addition, Matošević et al. (2017) reported that field-collected C. perspectalis larvae starved to death (100% mortality) when provided with E. japonicus leaves. Similarly, Wiesner et al. (2021) also concluded that C. perspectalis could not survive or successfully pupate while being fed with E. alatus or E. fortunei during larval development in laboratory studies. In Europe, C. perspectalis has only been recorded from Buxus species (Bury et al 2017, Kenis et al 2013, Wan et al 2014). Van der Straaten and Muus (2009) also cite unpublished tests performed by the Plant Protection Service of the Netherlands that showed that European populations do not attack anything but Buxus. Based on the surveillance and control activities in Ontario, C. perspectalis has only been detected on Buxus spp. plants and not on Euonymus spp. or Ilex spp. When scouting C. perspectalis populations, field technicians would check nearby plants for C. perspectalis larvae or feeding damage (Euonymus spp., Pachysandra terminalis, Ilex spp.) but no signs of damage or C. perspectalis life stages have been found on these species to date. Given the above observations, it is reasonable to conclude that Euonymus spp. and Ilex spp. are not suitable hosts for C. perspectalis in Europe or in Canada.

Pathways for entry, establishment and spread

Introduction of C. perspectalis into Europe is believed to be via infested Buxus plants imported from East Asia (Kenis et al. 2013; Salisbury et al. 2012). Natural dispersal of adult moths might have been the primary method by which this moth arrived in the southern coast of England from continental Europe (Korycinska and Eyre 2011), from Germany to Switzerland (van der Straten and Muus 2009), and from Turkey to Greece (Strachinis et al. 2011). Data from Germany indicate that natural dispersal is about 5 to 10 km (van der Straten and Muus 2009). Eggs, laid on the underside of host leaves, and young larvae, with their greenish colour, can travel undetected on host plants (Kenis et al. 2013; Salisbury et al. 2012). Eggs, larvae, and pupae could survive long distance transport or storage on boxwoods (Plant et al. 2019, van Kretschmar 2017). There are 2 native species of boxwood, B. sempervirens and B. balearica that are found in the natural European environment. The shrubby nature of boxwood, especially in the nursery stage, provides deep pockets that make it easy for eggs and larvae to be well hidden inside the plant such that it takes effort to find them if present. In this state, they can survive and travel easily on plants, without being detected (Salisbury et al. 2012, Kenis et al. 2013).

There are currently no specific import requirements for boxwood coming into Canada. In general, consignments of plants for planting must be free of regulated pests and of soil and may also be subject to additional requirements depending on the species and country or region of origin. A phytosanitary certificate is required for all plants for planting imports, which includes inspection by the exporting country, and may be subject to inspection at the time of entry into Canada. Importation from areas other than the continental U.S. must be free from soil. Currently, Canadian nurseries propagate their boxwood from on-farm stock as a recommended best practice for the prevention of Cylindrocladium buxicola (boxwood blight). Some Canadian nurseries will purchase finished boxwood plants from U.S. suppliers for re-sale if stock is in short supply domestically. Best Management Practices at Canadian nurseries, including the adoption of a C. perspectalis pest module (trapping, monitoring, treatments, etc.), greatly support efforts to mitigate risks at nurseries and represent the best approach for limiting the spread of C. perspectalis via the nursery pathway.

In April 2021, C. perspectalis was first detected in a nursery through the on-farm C. perspectalis surveillance pest module. Following the detection, the nursery immediately stopped all shipments of host plants, notified customers, industry and government agencies, inspected and treated all host plants. Community science and surveillance was further expanded in the region in the Greater Toronto Area to delimit pest infested area.

Cydalima perspectalis can survive in areas with Buxus spp. hosts where the minimum winter temperature is about -30°C. It overwinters in the larval stage in a silken cocoon spun between host leaves. Temperature threshold for the development of eggs, larvae, and pupae vary between 8°C and 12°C. Main Buxus species in trade in Canada are Buxus sempervirens and B. microphylla. Buxus sempervirens is grown for landscaping purposes in the most temperate regions of Canada (Brouillet et al. 2010 +). Buxus microphylla is cultivated in Canada and nurseries in both British Columbia and Ontario offer this species for sale (Brouillet et al. 2010 +). Hybrid Buxus cultivars are very popular in Canada. They are hardy in both southern Ontario and British Columbia (Drysdale 2008). CLIMEX modelling maps, using both past and future realistic climate normals, strongly indicate this moth can and will survive in Canada. Specifically, In Ontario, from Toronto southward. It may also infest areas north of Toronto from Montreal to North Bay. Future establishment in British Columbia and the Maritimes seems possible (CFIA 2019d).

Potential economic consequences

Boxwood plants are considered by the nursery industry to be among the top 5 most important woody ornamental plants in Canada, with the annual value of transactions estimated at approximately $40 million, of which domestic sales amount to $15 million.

In June 2022, the CNLA reported a loss-to-date of sales of over $6.5 million dollars to their growers since the publication of U.S. Federal Order DA-2021-11. Most customers order boxwood as 1 of multiple items in an order and as such, growers are losing, or at risk of losing, customers due to their inability to supply all requested products. The CNLA has also reported that there will be potential impacts to U.S. customers, who rely on Canadian growers as seedling and transplant providers.

Pest management

Boxwoods infested by C. perspectalis can be treated with registered chemical insecticides or biopesticides based on Bacillus thuringiensis (Bt) (Kenis et al. 2013). Bioinsecticides based on Bt serotype kurstaki (Btk) have been effective against C. perspectalis larvae and is the recommended control method in Europe (Guérin, 2018; Göttig and Herz, 2016; Lefort et al., 2014). In Ontario, Btk provides excellent control of C. perspectalis larvae and can be used to effectively manage this pest when peak larval feeding for each generation is accurately identified. Some defoliated hedges were observed to recover after Btk treatment during each C. perspectalis generation.

Chelonus tabonus, Tyndarichus spp. and Trichogramma spp. are reported to parasitize C. perspectalis eggs (Göttig and Herz, 2016; Wan et al., 2014). Casinaria spp., Compsilura concinnata, Dolichogenidea stantoni, Exorista sp., Protapanteles mygdonia and Pseudoperichaeta nigrolineata are larval parasitoids of C. perspectalis (Belokobylskij and Gninenko, 2016; Shi and Hu, 2007; Wan et al., 2014). In laboratory studies, entomopathogenic nematodes Steinernema carpocapsae and Heterorhabditis bacteriophora caused high mortality of C. perspectalis larvae. Brachymeria lasus and Apechthis compunctator are pupal parasitoids of C. perspectalis (Wan et al., 2014). In 2021, scouting in Ontario led to observations of a parasitoid wasp (Ichneumonidae) attacking C. perspectalis pupae. A total of 7 specimens were collected over the summer. More research is warranted to assess wasps native to North America as well as Asian parasitoids of C. perspectalis to establish a viable biological control program in Ontario. Chelonus tabonus (Sonan), a larval braconid parasitoid, was identified as the most promising candidate for classical biological control due to its high parasitism in China.

In Ontario, pheromone traps, ground scouting, and community science surveillance (outreach and assistance with trap placement and monitoring) have been used to delineate the area of C. perspectalis infestation. Pheromone traps are an effective method of capturing adult male moths and are used to detect presence or absence of the pest in an area as well as to indicate flight period(s). Ground scouting is an effective means of detecting C. perspectalis. Removal and replacement of host plants from private properties was attempted when C. perspectalis was first detected in Toronto, but it was difficult to identify the location of all host plants and not all home owners were open to removal of host plants from their property. As this pest is reported to fly up to 10 kilometers, pest eradication by targeted removal or treatment of host plants from individual properties was deemed not feasible. The province of Ontario is working towards supporting long term management tools including insecticides and mating disruption. An integrated pest management approach is recommended for management of C. perspectalis in Southern Ontario which includes ground scouting, trapping, well-timed insecticide applications and a communication plan to engage and educate property owners to help detect, report and manage this pest.

Risk management considerations

Standards of the International Plant Protection Convention

Cydalima perspectalis is listed by USDA-APHIS on its Regulated Plant Pest List (USDA-APHIS 2020b).

International Standard for Phytosanitary Measures 5 (ISPM 5) defines a regulated quarantine pest as a pest of potential economic importance to the area endangered thereby and not yet present there, or present but not widely distributed and being officially controlled (IPPC 2022).

A quarantine pest must meet the definition of "a pest of potential economic importance to the area endangered thereby and not yet present there, or present but not widely distributed and being officially controlled". The guidelines for official control include, among other elements, that measures be mandatory and that domestic and import requirements should have the same or equivalent effect.

The CFIA conducted multiple assessments on various aspects of C. perspectalis including pestcategorisation, biology, hosts, pathways and potential impact over the past 10 years (2011-061, 2018-175, 2019-060, 2019-061, 2019-135, 2019-150, 2019-179, 2019-193, 2019-199, 2021-086, 2021-087, 2021-091, 2021-096).

Although the source of the detection of C. perspectalis in Canada remains unknown, its presence is an indication that there is a viable pathway of entry. The experience in Ontario has shown the ability of the pest to establish and spread. However, the pathway for introduction of the pest in Ontario remains unknown as it was first reported in an urban neighbourhood. There were no reports in the nursery sector until it spread naturally from the Toronto infestation. Natural dispersal is possible, but limited due to the lack of natural boxwood stands in Canada that would contribute to population growth and spread. Human-mediated spread is the primary means by which this moth spreads from 1 place to another. Economic and environmental consequences are rated medium as this moth has the potential to have significant negative impact on the trade of boxwood, especially with the United States.

Cydalima perspectalis satisfies the criteria of being present but not widely distributed and being of potential economic importance.

Risk management considerations

The CNLA has worked closely with its members and provincial partner associations to educate on this pest, and pest modules have been drafted to mitigate the risk of moving C. perspectalis with nursery plants. Since 2020, the CFIA has been working closely with the industry sector to develop a C. perspectalis systems approach, based on the principles of pest free place of production/site as per ISPM 10, to establish confidence and ensure the nursery pathway is not a pathway for spread. A pest-free place of production must have systems in place to: establish and maintain pest freedom, verify pest freedom, and maintain product identity and phytosanitary security of any shipment. In addition, Buxus spp., Ilex spp. and Euonymus spp. from Ontario are not sold to British Columbia. British Columbia is a major producer of these species and sells them to buyers in other provinces but, because of movement restrictions related to Lymantria dispar dispar (spongy moth) and Popillia japonica (Japanese beetle) in addition to the extended growing season and warmer climate in British Columbia, there is no market for Ontario product west of the Rocky Mountains.

Based on the surveillance and control activities in Ontario, C. perspectalis has only been detected on Buxus spp. plants. When scouting C. perspectalis populations, field technicians would check nearby plants for C. perspectalis larvae or feeding damage (Euonymus spp., Pachysandra terminalis, and Ilex spp.) but no signs of damage or C. perspectalis life stages have been found on these species to date. These observations align with the findings of Wiesner et al. (2021), who confirmed that C. perspectalis could not survive or successfully pupate while being fed E. alatus or E. fortunei during larval development in laboratory studies. Following the detection of C. perspectalis in New York State, control activities within the state have so far only applied to Buxus spp. plants from regulated counties to prevent the spread of C. perspectalis to other parts of the U.S. The CFIA believes that the scientific data currently available does not support the development of phytosanitary measures for Euonymus spp. and Ilex spp.as hosts of this pest.

Risk management proposals

In August 2022, the CFIA presented pest risk management options for C. perspectalis in Canada for consultation. Pros and cons are provided below for each proposed option.

Risk management option 1 – Status quo: No specific phytosanitary measures for C. perspectalis

Under this option, C. perspectalis would not be designated as a regulated pest in Canada. The CFIA would continue to work with stakeholders, including provinces and industry associations, to monitor the spread of the pest. CFIA will continue to support community science efforts, but will not conduct its own pest surveys. The CFIA will continue to advocate on the behalf of Canadian growers with respect to the U.S. Federal Order, based on surveillance data from growers, public reports, and provincial stakeholders. Pest modules for C. perspectalis will continue to be recommended for any facility that produces Buxus spp., Euonymus spp., and Ilex spp. Establishment of Pest-Free Places of Production and Pest-Free Production Sites based on the principles of ISPM 10 will also be encouraged. Industry has recently expressed a commitment to ensure that the nursery stock pathway will not be a pathway for spread of the pest. Emerging populations, when detected, could be controlled by host removal or treatment by industry and/or provincial stakeholders.

Pros:

as Buxus spp. are the only hosts of C. perspectalis and as Buxus spp. are non-native to Canada, the economic and environmental impacts to Canada will be limited to the nursery and landscape industry in Canada
natural spread of C. perspectalis may be slowed by the absence of natural stands of boxwoods in Canada
industry would continue to be able to trade inter-provincially without restrictions or additional phytosanitary requirements
continue to rely on industry best practices

Cons:

the nursery industry may be limited to domestic sales for an extended period of time
domestic sales of Buxus spp. may decline as the risk of the pest increases, further impacting the $15 million domestic market
it is anticipated that exports of the 3 plant taxa will continue to be prohibited entry into the U.S. until USDA-APHIS de-regulates C. perspectalis, recognizes trapping data indicating that the pest is confined to Ontario or is satisfied that the risks associated with the importation of the 3 taxa has been sufficiently mitigated and amends their current import requirements

Risk management option 2 – Federal regulation of the pest – Creation of a localized regulated area in the Greater Toronto Area (GTA) and Niagara peninsula (municipalities with positive detections from 2021)

Under this option, C. perspectalis would be added to CFIA's Regulated Pest List and would become federally regulated pest. This option would involve:

the establishment of a regulated area in the Greater Toronto Area (GTA) and the Niagara peninsula which would be considered infested with C. perspectalis (see figure 3)
regulatory controls applied to Buxus spp. only (see Host plants section above)
implementation of domestic movement controls for Buxus spp. moving out of the regulated area. Specifically, facilities producing Buxus spp. within the regulated area would be required to implement a systems-approach to prevent pest spread (for example, pest module) if they want to move or sell Buxus spp. outside the regulated area
movement of Buxus plants out of the regulated area would require authorization by an inspector, through an inspection and issuance of a Domestic Movement Certificate
- Authorization would be dependent on the systems in place at the facility and may require visual inspection by CFIA inspectors
unrestricted movement of Buxus spp. within the regulated area
surveillance focussing on production areas outside the regulated area
implementation of import restrictions including prohibition of imports of Buxus spp. from the infested area in New York State, U.S, into British Columbia.
Other prohibitions/restrictions may also be necessary

Pros:

provides control measures to slow the human assisted spread of the pest throughout Ontario and the rest of Canada
alignment of pest regulatory status with the U.S.
responds to industry request for regulation to support re-establishment of trade with the U.S

Cons:

requires a more labour-intensive systems approach for preventing movement of potentially-infested plants until treatment has been applied
CFIA will be required to enforce domestic movement requirements and resources will be redirected from other priority activities
this option is the most resource intensive for the CFIA and potentially also for industry
expansion of the regulated area may be required soon after publication based on the results of the 2022 survey
- While the distribution of C. perspectalis in 2021 was restricted to the Greater Toronto Area and Niagara region, new detections reported in 2022 are well outside these areas including the far south west of the province (that is, Windsor area)

Proposed regulated area in the GTA and Niagara peninsula. Description follows. — Figure 3 – Option 2 – Proposed regulated area in the Greater Toronto Area (GTA) and Niagara peninsula
(note the actual regulated area may vary)

Risk management option 3 – Federal regulation of the pest – Creation of a regulated area for all of Ontario (recommended)

Under this option, C. perspectalis would be added to CFIA's Regulated Pest List. This option includes:

establishing a regulated area encompassing the entire province of Ontario (see figure 4)
regulatory controls applied only to Buxus spp. (see Host plants section above)
implementation of domestic movement controls for Buxus spp. moving out of the regulated area
- Specifically, facilities producing Buxus spp. within the regulated area would be required to implement a system to prevent pest spread (such as, pest module) if they want to move or sell Buxus spp. outside the regulated area. Facilities further from main area of infestation may qualify to establish Pest-Free Places of Production and Pest-Free Production Sites in accordance with ISPM 10
movement of Buxus spp. plants out of the regulated area would require authorization by an inspector, through an inspection and issuance of a Domestic Movement Certificate Authorization would be dependent on the systems in place at the facility and may require visual inspection by CFIA inspectors
unrestricted movement of Buxus spp within the regulated area
surveillance focussing on production areas outside the regulated area
implementation of import restrictions including prohibition of imports of Buxus spp. from the infested area in New York State, U.S., into British Columbia. Other prohibitions/restrictions may also be necessary

Pros:

no domestic movement restrictions within Ontario
provides control measures to slow the human-assisted spread of the pest out of Ontario to the rest of Canada
alignment of pest regulatory status with the U.S.
responds to industry request for regulation to support re-establishment of trade with the U.S.
new detections in Ontario will not require a change to the regulated area and provides a significant buffer from the current infested area to other provinces

Cons:

requires a more labour-intensive systems approach for preventing movement of potentially-infested plants until treatment has been applied but number of impacted plants will be reduced as all sales within Ontario will be in the regulated area
CFIA will be required to enforce domestic movement requirements and resources will be redirected from other priority activities

Figure 4 - Proposed regulated area for all of Ontario. Description follows. — Figure 4 – Option 3 – Proposed regulated area for all of Ontario

Risk management decision

Consultation

Comments on this risk management document were solicited from stakeholders from August 5 to September 3, 2022. All comments received were reviewed and taken into consideration. All comments received supported regulation of the pest. The majority respondents expressed support for option 3. A small number of respondents supported option 2 as more suitable for a slow-the-spread approach to the management of C. perspectalis, but with 2022 reports of C. perspectalis in LaSalle and Tecumseh, Ontario, in the far south western region of the province, regulation of the entire province was determined to be the most appropriate regulatory option. It should be noted that Buxus spp. plants are not winter hardy in the most northern regions of Ontario and regulating all of Ontario will not impact nursery producers in those areas.

Decision

Based on the risk assessment, and after analyzing all comments received, the CFIA has decided to move forward with option 3.

This option protects the nursery industry with a responsive approach to risk mitigation of C. perspectalis, while supporting market opportunities.

Under this option, C. perspectalis will be added to CFIA's Regulated Pest List and a regulated area for the entire province of Ontario will be created with regulatory controls applied on domestic movement and importation of Buxus spp.

By regulating C. perspectalis, the CFIA has the authority to apply phytosanitary measures on movement of host material and to respond to incursions by applying official control measures. The decision to regulate strengthens our cooperation and aligns with current U.S. requirements for C. perspectalis.

Endorsement

This risk management document has been approved by the Chief Plant Health Officer.

References

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Date modified:: 2022-11-23

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RMD-22-02: Pest risk management decision for the regulation of Cydalima perspectalis in Canada

Preface

On this page

Executive summary

Purpose

Scope

Definitions, abbreviations and acronyms

Background

Pest risk assessment summary

Pest biology

Host plants for C. perspectalis

Pathways for entry, establishment and spread

Potential economic consequences

Pest management

Risk management considerations

Standards of the International Plant Protection Convention

Risk management considerations

Risk management proposals

Risk management option 1 – Status quo: No specific phytosanitary measures for C. perspectalis

Pros:

Cons:

Risk management option 2 – Federal regulation of the pest – Creation of a localized regulated area in the Greater Toronto Area (GTA) and Niagara peninsula (municipalities with positive detections from 2021)

Pros:

Cons:

Risk management option 3 – Federal regulation of the pest – Creation of a regulated area for all of Ontario (recommended)

Pros:

Cons:

Risk management decision

Consultation

Decision

Endorsement

References