Table 6.

Overview of implemented risk mitigation measures for Acer campestre plants designated for export to the EU from the UK

Number	Risk mitigation measure	Implementation in the UK
1	Registration of production sites	All producers are registered as professional operators with the UK Competent Authority via APHA for England and Wales or SASA for Scotland and are authorised to issue the UK plant passports, verifying they meet the required national sanitary standards (Dossier Section 1.0).
2	Physical separation	Producers do not set aside separate areas for export production. All plants within the UK nurseries are grown under the same phytosanitary measures, meeting the requirements of the UK Plant Passporting regime (Dossier Section 1.0).
3	Certified plant material	Seeds purchased in the UK are certified under The Forest Reproductive Material (Great Britain) Regulations 2002. Seedlings sourced in the UK are certified with UK Plant Passports. Seedlings from the EU countries are certified with phytosanitary certificates. Many plants are obtained from EU (mostly the Netherlands) and New Zealand. These are the only two sources of the plants obtained from abroad (Dossier Section 3.0).
4	Growing media	The growing media is virgin peat or peat‐free compost. This compost is heat‐treated by commercial suppliers during production to eliminate pests and diseases. It is supplied in sealed bulk bags or shrink‐wrapped bales and stored off the ground on pallets, these are free from contamination. Where delivered in bulk, compost is kept in a dedicated bunker, either indoors or covered by tarpaulin outdoors and with no risk of contamination with soil or other material (Dossier Section 1.0).
5	Surveillance, monitoring and sampling	For additional information see Section 3.3.3 Pest monitoring during production.
6	Hygiene measures	Growers must assess weeds and volunteer plants for the potential to host and transmit plant pests and have an appropriate programme of weed management in place on the nursery (Dossier Section 1.0). General hygiene measures are undertaken as part of routine nursery production, including disinfection of tools and equipment between batches/lots (Dossier Section 1.0) and different plant species (Dossier Sections 1.0 and 3.0). The tools are dipped and wiped with a clean cloth between trees to reduce the risk of virus and bacterial transfer between subjects. There are various disinfectants available, with Virkon S being a common example (Dossier Section 3.0).
7	Removal of infested plant material	Post‐harvest and through the autumn and winter, nursery management is centred on pest and disease prevention and maintaining good levels of nursery hygiene. Leaves, pruning and weeds are all removed from the nursery to reduce the number of over wintering sites for pests and diseases (Dossier Section 1.0).
8	Irrigation water	Water for irrigation is routinely sampled and sent for analysis (Dossier Section 1.0).
9	Application of pest control products	Crop protection is achieved using a combination of measures including approved plant protection products, biological control or physical measures. Plant protection products are only used when necessary and records of all plant protection treatments are kept (Dossier Section 1.0). Examples of typical treatments used against mildew, Botrytis, spider mites, aphids and thrips are detailed in the Dossier Section 3. These would be applied at the manufacturers recommended rate and intervals (Dossier Section 3.0).
10	Measures against soil pests	There are no specific measures/treatments against the soil pests. However, containerised plants are grown in trays on top of protective plastic membranes to prevent contact with soil. Membranes are regularly refreshed when needed. Alternatively, plants may be grown on raised galvanised steel benches stood on gravel as a barrier between the soil and bench feet and/or concreted surfaces (Dossier Section 3.0).
11	Inspections and management of plants before export	The UK NPPO carries out inspections and testing where required by the country of destination's plant health legislation, to ensure all requirements are fulfilled and a valid phytosanitary certificate with the correct additional declarations is issued (Dossier Section 1.0). Separate to any official inspection, plant material is checked by growers for plant health issues prior to dispatch (Dossier Section 1.0). A final pre‐export inspection is undertaken as part of the process of issuing a phytosanitary certificate. These inspections are generally undertaken as near to the time of export as possible, usually within 1‐2 days, and not more than 2 weeks before export. Phytosanitary certificates are only issued if the commodity meets the required plant health standards after inspection and/or testing according to appropriate official procedures (Dossier Section 3.0). The protocol for plants infested by pests during inspections before export is to treat the plants, if they are on site for a sufficient period of time or to destroy any plants infested by pests otherwise. All other host plants in the nursery would be treated. The phytosanitary certificate for export will not be issued until the UK Plant Health inspectors confirm that the plants are free from pests (Dossier Section 3.0).
12	Separation during transport to the destination	According to the Dossier Section 3.0, the commodities are dispatched as single bare root trees or in bundles as follows: 25 or 50 for seedlings or transplants; 5, 10 or 15 for whips. Bare root plants are placed in bundles, wrapped in polythene and packed and distributed on ISPM 15 certified wooden pallets or metal pallets. Alternatively, they may be placed in pallets which are then wrapped in polythene. Small volume orders may be packed in waxed cardboard cartons or polythene bags and dispatched via courier (Dossier Sections 1.0 and 3.0). Rooted plants in pots are transported on Danish trolleys for smaller containers or certified pallets or individually in pots for larger containers (Dossier Section 1.0).