Author:  Dr Matt Elliot (RBGE) and Alistair Yeomans (Plant Healthy Certification Scheme)

The role of live plant movements in the spread of plant pests and diseases is now widely acknowledged. It is becoming increasingly clear that growers and plant handlers have responsibility for ensuring that the biosecurity risks along the supply chain are kept to an appropriate level. But how do they know where the high-risk points are and how do they minimise these risks?

The Plant Health Centre is funding two projects which aim to clarify the risks associated with a) plant waste disposal and peat free media, and b) visitors to sites, tools and machinery movement, and come up with solutions for all live plant handlers.

What to do with plant waste material has been an issue for some time, particularly in plant production nurseries. Material is often just added to a waste heap somewhere on the nursery in the hope that it will eventually breakdown. This has been shown to be a biosecurity risk as quite often these heaps contain pests and diseases which can leach out onto nearby healthy plants. Project PHC2021/02 is therefore in the process of producing very clear management guidance for anyone who has to manage plant waste. This will improve biosecurity in many businesses and organisations across the country.

Plant producers face another dilemma, they want to move towards peat free production but there are a number of issues. There is currently considerable inconsistency in peat free compost that translates to the irregular growth of plants, which is unacceptable to growers who can’t afford to absorb such failures. In addition, it is not always clear where the components of peat free compost come from (e.g., coir, bark) and this represents a biosecurity risk. Project PHC2021/02 is also looking at these risks and other barriers that are preventing businesses moving to peat free production.

It is well known that plant pathogens can move around on footwear, tools and machinery. Public gardens need visitors and volunteers to function, while agriculture often needs to share expensive machinery cooperatively, so how can the risk of disease spread in these cases be reduced? Project PHC2021/01 is investigating current biosecurity practices related to these risks, as well as examining other sectors (e.g. animal health, invasive species management) and international examples, to potentially find novel solutions. The resulting review will clarify the current situation and provide a clear way forward for improvements in biosecurity.

In addition to this, both of these PHC funded projects will provide evidence that will be used to inform the Plant Health Management Standard (PHMS). Any business or organisation that handles plants can apply to become Plant Healthy Certified where they undergo a plant health audit (against the PHMS) to assess their plant biosecurity systems and improve them over time. The evidence and guidance produced by these projects will be included in the Standard, thereby improving biosecurity practices across sectors.

Photo courtesy of Sarah Green, Forest Research^©