As Observatree continues to expand our collaborative networks, we have recently teamed up with the Botanic Gardens Conservation International (BGCI) and PlantNetwork to help raise awareness of tree health in wider audiences and promote surveillance and reporting by more people.  

The BGCI coordinates a project called the International Plant Sentinel Network (ISPN), where more than 90 botanic gardens located around the world share information on non-native plants within their collections and how the cope with any plant pests or diseases that are found within those countries. As more pests and pathogens are now moving around the planet, there is always a risk that one of them will arrive here in the UK. Working with colleagues from across the IPSN help us to understand how our trees may react to any invasive pest or pathogen and what the symptoms may look like. Additionally, the IPSN aids the tracking of any pest or pathogen as they move from one are to another, helping to highlight particular risks that may be approaching and helping to act as an early warning system.

PlantNetwork is a collaboration of more than 80 gardens, groups and organisations from across the UK and Ireland who aim to promote public benefits of plant collections, support the use of collections for education, research and conservation, and promote high standards of management practice. Formed in 1996, the network continues to bring together representatives from various NGOs, gardens and collections, volunteer groups and anyone with an interest in plant growth or management to share expertise and practices through meetings, newsletters and events.


Through this collaboration, we are aiming to establish a UK Garden Sentinel Network (UKGSN), an initiative that is partly modelled on the US Sentinel Plant Network, which is a collaboration between the American Public Gardens Association and the National Plant Diagnostic Network (NPDN). That partnership provides public garden professionals with training and diagnostic support to better monitor and protect their collections. It also enhances garden outreach efforts to educate their communities on the impact of high-consequence plant pests and pathogens.

Our proposed UKGSN brings together:

  • Technical expertise on the identification and monitoring for key tree pests and diseases through a number of sources including tree and plant health staff within Observatree and other members of the International Plant Sentinel Network (IPSN ).
  • Citizen science experience within Observatree, where an understanding of training methods, and reporting systems, are well established.
  • The combined plant collections of the UK botanic gardens, arboreta and other organisations include a very wide range of species and provide ideal locations for pest monitoring, particularly because the host tree species to be monitored are well identified. These collections are already linked through membership of PlantNetwork, and have significant numbers of staff and volunteers who would be well placed to contribute to plant health monitoring activities.


As a proof of concept, the UKGSN will initially focus on tree health where Observatree and TreeAlert are already in place to support training and data capture. Future discussions will explore opportunities with other stakeholders and potential partners for wider expansion or replication into other areas of plant health.

For this initial survey, we have asked potential participants in the UKGSN to look for the Great spruce bark beetle, the Elm zigzag sawfly and the European mountain as ringspot associated virus, as they are believed to be widely distributed, but data on their current whereabouts is often sparse. Where they are not found and the host trees appear to be otherwise healthy, that information can also be submitted through TreeAlert to help us build a clear understanding of distributions.

We are pleased to be working with both the BGCI and Plant Network on this new initiative and we look forward to developing strong links with them as this work develops.