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phytothreats workshop 4 october

October 4th 2017, APHA, Sand Hutton, York

Sarah Green, Phyto-threats project co-ordinator, welcomed everyone and introduced the aims of the workshop. These were to:

  • share key science findings from the Phyto-threats project which might help underpin accreditation

  • understand existing UK assurance schemes and how they might be supported

  • generate ideas for how an accreditation scheme should work in order to be effective

The meeting was attended by c50 nursery managers, Plant Health inspectors, foresters, academics, policy makers and others. This report provides an overview of the presentations given on the project team’s research; existing and emerging schemes (UK Sourced and Grown scheme and HTA’s pilot project); and Defra’s position on accreditation. Slides accompanying these talks are available on the Phyto-threats project website (see link above). The report also includes the outcome of discussions when attendees were asked to share thoughts and experiences on ‘how to give accreditation teeth’.


Sarah Green (Forest Research) welcomed the delegates and provided an overview of the project, reiterating the aim to address global threats from Phytophthora species, and to mitigate disease through nursery best practice. The progress of the project to date was summarised, and it was stressed that a number of lessons had been learned surrounding appetite for accreditation, and drivers and challenges facing nurseries (both from partner nurseries and from the overseas perspectives of Susan Frankel (USA) and Giles Hardy (Australia) who featured in last year’s workshop). Sarah concluded by outlining the aim of this workshop: to explore how to make accreditation work and how it should be supported. In addition, the workshop served as an opportunity for partners to hear about the specifics of the research implemented over the past year.

Dave Cooke (James Hutton Institute) spoke on the sampling procedures used during his team’s visits to nursery sites, and the subsequent findings the ongoing analyses are yielding. Samples from fifteen partner nurseries have been collected, including 8 nurseries in Scotland, 6 in England and 1 in Wales. In total over 1700 samples have been collected to date. Analysis of these samples is ongoing. Over 400 samples have been PCR tested for Phytophthora (93 from plant roots of 35 different hosts; 132 water filters; and 170 buffer solutions associated with the filters). The analysis is key to understanding which Phytophthora species are found in nurseries and which management practices contribute to spread or mitigation. This information is expected to help inform nurseries which Phytophthora species represent an emerging threat, allowing proactive action to be taken. Early analysis appears to be demonstrating that mud and puddles, unmanaged shelter belts and ‘hospital areas’ for sickly plants all increase the risk of Phytophthora being harboured.

Mike Dunn (Forest Research) summarised the findings of a consumer survey from 1500 UK plant buyers. The results showed that the public have little awareness about the threats from newly introduced pests and diseases, or the specific pathogens already present. Moreover, when choosing where to buy plants, quality, cost and range of plants are the most important drivers. Presence of biosecurity practices and plant provenance are unimportant in comparison. In terms of acquisition, the most relied upon sources are garden centres (used by 80% of the sample), DIY stores (56%), supermarkets (48%), self-grown from seed (47%) and nurseries (36%) – highlighting the value of an accreditation scheme that could encompass more than just nurseries. Data on purchasing behaviour demonstrated that many of the public buy other accredited/certified products (e.g. Fairtrade products) on the grounds that they agree with the ideals of the scheme, but also because the status implies a high quality product. Forty-five percent stated they would be likely to travel further to buy accredited plants (mean distance of 26.2 miles each way), and 39% reported they would be likely to pay an additional premium (mean premium of 18%). It was acknowledged that the general public represent one of several different types of consumer for nurseries. Further research into other customers (e.g. landscapers) is ongoing.

Dan Chapman (Centre for Ecology and Hydrology) moved away from thinking about nurseries to look at the national and global scales of plant movement and colonisation. Particular attention was paid to variations in environmental conditions, and the associated implications for the level of risk posed by different Phytophthoras. This process has involved tapping into global databases on trade and looking at reports of Phytophthora introductions, understanding links between traits and impact, and working towards predicting ‘invasiveness’ in the UK (on the basis of traits and the country’s climatic conditions). Pursuing this research may aid in assessing whether a newly discovered or introduced Phytophthora will be problematic. As such, it is relevant for national scale biosecurity planning, and collaborators connected to the UK plant health risk register.


Lee Dudley (Woodland trust) described the Woodland Trust’s UK Sourced and Grown (UKSG) assurance scheme relevant to forest nurseries. Prior to the scheme the Trust were ‘spot buying’ plants from mainland Europe, though this was considered a problem in light of the ash dieback outbreaks. After research and face-to-face discussion with nurseries it was decided that contract growing and seed collection would represent a more secure means of attaining healthy trees from within the UK. Nurseries and seed collectors are now encouraged to seek accreditation, and produce assured products for the Trust. Staff training, seed handling, traceability, stock control, biosecurity, plant quality and quantity, care of soil and water, and seed receipts are all assessed as part of the accreditation process. A total of 30 nurseries were approached for inclusion, leading to 19 agreeing to be audited and subsequently passing, and an additional one requiring corrective action. As a result, an estimated 56.8 million plants have been assured. While the contracts are significant to the forest nursery sector (£2-3 million per year), a huge gap is predicted between what is being supplied by forest nurseries and the number of trees that are expected to be needed in the future. It is hoped that more nurseries and seed collectors will be encouraged to join the scheme, which offers a guaranteed market for assured produce and is a good advert for the nursery. Growth of the scheme will continue to reduce the reliance on spot buying.

Tim Edwards (Boningale Nurseries) provided an overview of the HTA Plant Health Assurance Scheme which is now in its pilot stage. The scheme includes 10 nurseries of varying size and type that are currently being audited as a means of testing the proposed standard for the scheme. It was noted that the nurseries participating are likely to be better than average at managing for biosecurity risks having volunteered to be part of the pilot. However, auditors are noting a number of shortcomings such as a lack of risk assessment, the absence of records of disposals, and a need for further staff training. Those involved are said to be pleased with the process which is helping them to become exemplars within the sector – something which customers such as retailers and amenity planters look favourably upon. A project meeting in November 2017 will explore the governance of the scheme and establish an independent entity that will own and oversee a refined standard for future use. All nurseries will be offered the chance to get up to speed for when the scheme rolls out to avoid giving undue advantage to those participating in the pilot scheme.


Nicola Spence (Defra’s Chief Plant Health Officer) acknowledged Defra’s interest in accreditation as well as preventative measures, for example through more thorough host inspections (particularly for highly susceptible species). To illustrate the scale of the challenge faced, Nicola referred to the growing risk register, which typically receives 5-10 new additions at each monthly meeting, and emphasised the need for 5 P’s within the trade: predicting, preventing, protecting, preparing and partnering. Defra’s stance is that nursery accreditation could be an important element in shaping the UK as a trusted provider of quality plants (with reduced pest and disease risk) and thus a bigger exporter. Reducing the number of imports and employing measures on those that do still need to be imported (e.g. quarantining) could not only lower biosecurity risk but also foster financial resilience within the industry. This resilience could be furthered by restructuring of a grant scheme currently operating for Phytophthora and a limited number of other pathogens. Defra and APHA should remain a source of information on plant pests and diseases via the plant information portal. In addition, Nicola agreed with a suggestion that Defra should influence planning and development policy to insist on the use of accredited nurseries or products during developments, once a standard had been agreed upon as to what is a bio-secure plant.

2. How to Give Accreditation Teeth: Uptake, Compliance and Impact

2.1 Accreditation coverage

Need for extensive coverage : In order for an accreditation scheme to have impact it was agreed that it would need to be; endorsed by the government, critical to the business, and to encompass the products/practices of as many actors within the supply chain as possible. This coverage is deemed necessary given that retail outlets received criticism for current practices, such as offering ‘bargain priced plants’ which had been retained so long as to increase the probability that they harboured pathogens – something which would not be tolerated with the sale of food or animals.

Challenges for widespread inclusion: Developing and implementing a scheme capable of maintaining relevance and appeal to all of the actors within the supply chain is considered a key challenge, undermined by a number of factors. UK nurseries were said to be too small to satisfy the enormous customer base resulting in a sizeable market share for non-specialist traders including supermarket and DIY chains. While the establishment of UK cooperatives emerged as a potential means of rolling out accreditation to a larger number of growers, it was noted that at present different actors appear to be pursuing their own approaches rather than uniting towards a single cross-cutting, standardised approach. For example, one DIY store are said to have a new ‘unification scheme’ which may involve selling only their own branded products, similar to the Ikea model. Other groups have sought to improve the quality of plants by using suppliers accredited under the BOPP scheme. While these developments serve to demonstrate that many have come to recognise the value of some form of assurance/accreditation approach, it is possible that the diversity of what is being proposed will lead to confusion among customers.

Building on existing frameworks : Examples given of successfully established, widespread schemes included sustainable timber schemes and pesticide schemes, raising the question as to whether lessons could be learned from these, or if there was an opportunity to ‘piggyback’ – adding biosecurity best practice to an existing scheme. It was agreed that ideally the UK should have a single, recognisable assurance scheme and that existing schemes (ie UKSG, HTA, BOPP) should be amalgamated, yet how this could be achieved was not clear.

International coverage: While discussions focussed on encouraging accreditation coverage among the different stakeholders in the UK, others felt strongly that a UK wide accreditation scheme would in fact need to be mandatory for all growers if it were ever to be effective. Certain nursery managers and DIY chain representatives went further still, expressing that accreditation should extend not only to countries on the continent – from which the UK receives the majority of its plants – but also to countries outside of Europe. This, they believed, was necessary to ensure that the plants arriving to and leaving from European nurseries could be considered “safe”.

2.2 Support needed within the trade

Ensuring demand for accredited plants : Growers investing in enhanced biosecurity practices seek assurance that their products will be in demand. One way to help ensure this is for the government to insist that contracts must specify the need for accredited trees/plants. However, at present Local Authorities are routinely awarding contracts to the lowest bidder, with little to no attention being paid to plant type, quality or health. More generally, contract growing has not been successful because of a tendency for schemes to be put on hold or not to materialise at all. As a result, it can be extremely difficult to match supply with demand. Ideally procurement/contract growing should nominate an accredited supplier to ensure that plants and trees purchased arrive from a site with the necessary biosecurity practices in place. In addition, there should be a guarantee that the plants/trees will be needed and therefore purchased. This would ensure that growers can manage their supply without fear of the demand disappearing at short notice, and losses being incurred.

Benefits for accredited growers : In the event that a contract is terminated or amended (thus reducing the number of plants/trees required) growers would require an insurance policy or compensation to offset any costs invested in producing the order. By making access to this type of insurance scheme available only to those growers that had been accredited, it would be possible to discourage acquisition of plants from riskier pathways typified by the ‘white van man’ – since traders ineligible for the insurance would be subject to wasted resources when a contract is cancelled, and therefore be at a disadvantage in the marketplace. Other suggested benefits to holding accreditation included eligibility to grant funding and access to different markets (i.e. allowing for the purchase of plants from certain places). Again, these measures would potentially put those without accreditation at a disadvantage and reduce their market share.

Insurance providers : While it was suggested that the government may oversee the administration of financial incentives/reimbursement for those with accreditation, there was a degree of cynicism about how likely this would be. Nevertheless, some did view revisions to the government’s post-Brexit budget as an opportunity to introduce such measures. Other insurance providers were also suggested though it was acknowledged that more discussion would be needed to outline the specific circumstances required for reimbursement, and what level of reimbursement would occur. At present insurance policies which reflect the complexities of the trade were said not to exist, prompting some to highlight a need for the insurance sector to adapt.

Consistent support : In addition to a proposed role in reimbursement, there was also consensus that the Government would need to offer wider support for an accreditation scheme, and be consistent in its efforts to encourage its uptake and effectiveness, for example, by outlining a joined up vision between departments (less silo-ing). Consistency should be visible from the national level (e.g. increasing border controls and inspections), down to local governments, who are considered important due to their role in dealing with outbreaks on the ground. Many also noted a desire for the government to act in an educational role through the provision of more information on the cost of outbreaks, so as to highlight the extent of financial impacts which result.

2.3 Awareness and Education

Importance of awareness and education : Discussions around education and raising awareness were deemed relevant to plant buyers (including the plant buying public, landscapers, and middle-men in the supply chain) and wider society. Without the knowledge of what accreditation is trying to achieve and what it represents, it cannot be expected to garner support or influence spending behaviour.

Government signs : Achieving improved awareness of Plant Health and its importance was seen by many to be the responsibility of the government and its relevant departments (e.g. DEFRA, APHA). To achieve this aim it was agreed that the problems accreditation would attempt to solve must be made visible to the point where they simply cannot be missed or ignored. Suggested strategies for public spaces included signage throughout transport networks, typified elsewhere by the large, unmissable signs (e.g. bordering Canadian highways in and out of at-risk areas). Bus shelters and airport signage were similarly suggested. The imagery used in these instances could include altered landscapes, featuring ‘before and after’ photographs in outbreak areas, or artificial images to demonstrate how a currently valued landscape would likely appear following a loss of trees.

Media campaigns : TV campaigns, comparable to anti-smoking and green cross code advertisements were thought to be the most effective way to bring the message around the need for accreditation into the publics’ homes. This was thought to give the public little choice but to see and hear the required information. In contrast, online resources (such as videos or factsheets) are thought to have less impact – since people would actively have to seek out this information themselves it is unlikely that a sizeable proportion of the population would benefit from this form of exposure. For both TV and online content there was some concern that cartoons have a lifespan, and that beyond this the content may become ignored or tiresome if not periodically reinvented. Even with an ongoing campaign, there remained some scepticism that awareness would be long-lasting, and that many people would pay little attention to the issue until they themselves were directly impacted – i.e. through receiving diseased plants or recognising degradation or loss in a forest they used (e.g. discolouration or removal of numerous trees).

The role of growers and sellers : In addition to a government led blanket approach to raising awareness, it was agreed that growers and sellers have an important role to play owing to their first-hand interaction with consumers. As well as having signage and staff on-hand to communicate the problems associated with poor biosecurity and the goals of the scheme, it was felt that compliance with accreditation would need to be visible. This task would be best achieved with the presence of a recognisable accreditation logo that featured on accredited premises and products, alongside an explanation of the scheme’s aims and requirements.

Pressure groups : Pressure groups were also suggested as a means of raising the public’s awareness of risks within the trade. Greenpeace’s campaign to raise awareness about the use of neonicotinoids in pest control put pressure on growers to stop using these products, leading some to suggest that similar action could be employed to address the sale of high risk plants.

Message tone and content : In terms of the tone of the information being disseminated, it was suggested that finger pointing be avoided and instead the focus be on informing about the problem and its solutions. Others felt that there was a need to go beyond informing on the threat to the landscape, and to educate customers on what goes into growing a plant – something which may chime with the large proportion of those whose buying choices are influenced by plant quality. Some went as far as to say that accreditation should include a warranty/guarantee to customers to demonstrate that the product is high-end and worth paying for. Whatever the avenue for engaging with the public, it was deemed important that the message be succinct and trustworthy. Indeed, trust in the accreditation scheme and the growers are considered vital to the public’s receptiveness to supporting the scheme’s goals.

2.4 Training for the trade

Integration of training into accreditation : Early discussions around the posited and emerging accreditation schemes (including the HTA pilot project) have included proposals for ongoing improvement of a nursery’s practices in combination with staff training. Although the HTA pilot nurseries were described as having, “a lot to do, with few provisions” there is some optimism that inroads are being made, with DEFRA being particularly helpful in thinking about how training might be delivered.

Training options : Although the likes of SRUC’s new MSc on forensic plant health were highlighted as potentially valuable courses, they tend to be in short supply. In addition, the workforce of some nurseries are without the qualifications – and perhaps desire – to attain the level of expertise suggested to be necessary, meaning this formal education approach would prove inaccessible or incongruous to many workers. Instead, the idea of having an assigned officer within the organisation (equivalent to a health and safety officer) was proposed. This could be encouraged by making the presence of such a position a compulsory requirement for accreditation.

Knowledge and skills throughout the sector : Some felt that plant health professionals should be embedded in other professions including landscape design and retail. This measure was seen as a means of reducing the promotion and demand for high-risk trees and plants (such as olive trees and Himalayan balsam). It would also presumably help move towards a sector-wide commitment to selling only those plants which are in season, and more generally, facilitating sound biosecurity becoming revered throughout the supply chain. The upcoming introduction of a training module by the Landscape Institute is one example where increasing knowledge of plant health and best practice will soon be encouraged. Meanwhile in Scotland, the Confor nursery group is looking to see how to offer and deliver training on plant health to growers.

The rewards of training : Finally, it was suggested that the best practice and training required for accreditation should be something which is promoted to the growers on the grounds that a better quality product would result. On this basis, accreditation may become an asset (a badge of honour for growers and sellers), rather than representing red tape or a tick box exercise.

2.5 Challenges

Added costs : One nursery manager queried whether accreditation would necessitate more costs for the consumer – something which may undermine a scheme and accredited businesses should plant buyers opt to go elsewhere in search of cheaper goods. They reasoned that if implemented efficiently within nurseries, biosecurity should not be excessively costly and thus the costs passed on to consumers would be negligible. However, others with knowledge of schemes elsewhere insisted that it would be impossible for many nurseries to enact management changes and improved biosecurity measures without increasing the price of its products. In addition, it was noted that any input from plant health inspections would be expensive to growers, since inspectors charge even for 15 minutes of their time. Therefore, resources need to be put in place so that a scheme can be policed without excessively burdening growers. This policing may involve inspectors and auditors being granted the power to force changes on nurseries. The idea of a yellow/red card system for those who have failed to comply was also suggested, yet the specifics about whether non-compliance would result in any loss of privileges or the incurrence of fines – and over what timeframe – require further discussion.

Limitations to accreditation : Finally, it was acknowledged that an accreditation scheme could only be expected to reduce the risk of pathogen spread as oppose to eliminate it. For this reason, some raised concerns about the robustness of a scheme’s credibility in the event of an outbreak, particularly if it were to occur in the early days of a scheme being rolled out. As it is impossible to discount this possibility, the participant cautioned against overselling what the accreditation scheme could achieve.


  • A single, all-encompassing UK accreditation scheme is preferred

  • Accreditation needs to cover the entire supply chain if it is to have impact

  • Demand for accredited products should be ensured to incentivise uptake in the scheme

  • Accreditation could also be incentivised by allowing access to grant funding, and through financial reimbursement when contracts to supply accredited plants are cancelled/altered

  • It is necessary to raise public awareness about the need and benefits of accreditation through highly visible campaigns and signage, including a recognisable logo

  • Training for growers and others in the sector should be integral to accreditation so that practices continue to improve

  • For a scheme to be respected and to generate improvement it must be effectively policed