14.00 – 16.30, Tuesday 27th January 2026 (via Microsoft Teams)
Meeting chair: David Slawson (DS), Imperial College London
Microsoft Teams Organiser: Lucy Turner (LT), Forest Research, Alice Holt
Decisions and actions – for information only
Welcome
DS welcomed everybody to the meeting, in particular new attendees who introduced themselves, including Allison Terrell (APHA), Catherine Burton (JNCC), Jasmine Salvati (JNCC), Paul McCullough (Welsh Government); and Bryony Littlewood (Welsh Government).
THCSN Business
Actions/matters arising from the July 2025 meeting (if not on agenda)
Two actions are ongoing: inclusion of the Tree Health Citizen Science Learning Pathway in Defra’s Natural Capital and Ecosystem Assessment (NCEA) Citizen Science Resource Library and collaboration with Action Oak.
Communications: website usage, jiscmail, biogs, research summaries, news items etc.
- Website: Tom Jenkins (Forest Research Wales) reported that activity to the website had shown a marked increase; the Tree Health Learning Pathway for Citizens was the most visited page; and most common origins of visitors were: UK, USA, Singapore and Honk Kong.
- News item: DS explained that news items have been posted on the webpage most months; feedback was that the posts were of interest and value.
The Open University have publicised the learning pathway on their Treezilla resources page.
Action 1: All to send interesting items from their work to DS for inclusion on the webpage.
Venues/dates for next meeting(s)
Attendees expressed the following challenges of attending meetings in-person: time, expense and carbon emissions.
Decision 1: All future meetings will be held only online.
Decision 2: The date of the next meeting will be at 09.30- 12.00 on Wednesday 15 July 2026.
Priority Actions update
Enhance the tree health surveillance network
General update: Peter Crow (Forest Research) reported that one future focus for Observatree would be to engage with organisations which have established groups of volunteers.
UK Garden Sentinel Network (UK GSN): DS gave a brief recap and update on development of a UK GSN, including: a brief description of a similar network in the USA – the Sentinel Plant Network; the Memorandum of Understanding between Observatree, PlantNetwork and Botanic Garden Conservation International(BGCI) to lead development work here; an initial focus on trees to make as much use as possible of existing resources, in particular, Observatree/TreeAlert and BGCI’s International Plant Sentinel Network resources e.g. Plant Health Checker recording system; feedback from a small pilot in 2025 which highlighted the challenge of time and resources; a focus in 2026 to review existing to review existing resources, identify gaps, to adopt a train the trainers approach initially with a few willing volunteer organisations.
Mentioned in discussion was the excellent related work carried out by the Yorkshire Arboretum (who run a team of tree health volunteers and who have worked closely with BGCI), ‘Wales plant health sentinel site network’, and the RHS.
A philosophical concern was raised that asking people to focus only on specific pests and diseases might cause them to miss more general loss of health or indeed other pests and diseases.
Observatree are developing a Tree First concept to help people observe trees more systematically. AI was suggested as a potential tool to aid observation.
Data
DS gave a brief recap to set the scene, including: (a) a ‘pyramid of engagement’: low numbers of experts at the top; medium numbers of trained volunteers in the middle; both sitting on a foundation of high numbers of “the public” – the least developed but with the greatest potential to expand the surveillance network and generate data; (b) Tree Health Learning Pathway for Citizens, which shows how expertise can be increased and importantly recognises the potential for two-way engagement and data flow between the biological and biosecurity recording communities; and (c) Australia’s Atlas of Living Australia Biosecurity Hub which uses iNaturalist for citizens to record observations using their smartphone and the IT infrastructure of the Atlas of Living Australia(ALA) for the alert system (the UK’s NBN Atlas’s which use the same IT infrastructure as the ALA.
Defra summarised recent developments on the policy side including: their commitment to expand public engagement in tree health and to tree health citizen science; development of a ‘Trees Action Plan’, which should be published later in the year; work, including background research, to increase of engagement with people possessing some skills and knowledge (the middle tier of the pyramid); a pilot project on iNaturalist (Pest Watch – Plant and Tree Health Project) to examine engagement of the public in recording specific pests and diseases, which will be developed further.
Forest Research reminded attendees of the 2024 development a dashboard feature on TreeAlert to enable registered users to access and view data on the system.
Building on the Trees Outside Woodland (an ongoing National Capital Ecosystem Assessment programme run by Defra and designed to provide accurate information about the size, distribution, composition and condition of Trees Outside Woodland and how they interact with non-woodland ecosystems), the Centre for Ecology and Hydrology described further work to determine whether or not citizens can contribute towards ground-truthing the data, the suitability of CS methodologies and what CS data already exist that could potentially be drawn upon. They also sought other possible data sources and received the following suggestions: Google Maps, Great British Hedgerow Survey and their Healthy Hedges App, Leicestershire Nature Spot, County Highways Asset registers, Oak Mapper used in California to map outbreaks of Sudden Oak Death (Phytophthora ramorum) and ‘Differences between urban and rural hedges in England revealed by a citizen science project’ (Gosling et al 2016). Scotland’ Better Biodiversity Data project was suggested as an example where standardisation of varied data sources was being developed. Michael Pocock requested that anyone else who thinks of any other data should please get in touch with him.
Action
Observatree/TreeAlert update: Peter Crow (Forest Research/Observatree) reported that, to date, Observatree has generated over 30,000 reports; recruitment for new volunteers will commence in February 2026; and much of the funding for Phase 4 of the project has been secured.
Tour d’table
- Andy Moffat: a project is starting in the Petersfield area for local people to monitor the state of tree plantings on new residential estates
- Debbie Harding (BBSRC): a new cross-UKRI funding programme will commence shortly on “Food, Animal and Plant Health.”
- Ginette Alexander (Yorkshire Arboretum): volunteers have systematically recorded their collection; they have collaborated on the UK Garden Sentinel Network and use of TreeAlert; an article and poster (“The Wednesday Tree Murder Club”) are in preparation about the exercise.
- Phillip Wheeler (Open University): a new research paper has been published “A 3D data processing pipeline to automatically estimate tree dendrometric parameters from a single mobile phone video”
- Sam Village (Tree Council): There is a new The Tree Health Operations Forum which will meet three times a year to assess the ongoing challenges facing tree health and establishment, and the effectiveness of interventions to combat them. Get in touch with any questions or topics you’d like discussed in the next Tree Health Operations Forum by email to scienceandresearch@treecouncil.org.uk
Close
The meeting closed at 4.30pm.
6 February 2026
Dr David Slawson,
Coordinator THCSN