Social weaving moth larvae spotted in Enfield Chase
On 3rd June 2026, Open Woods wrote to key government agencies raising a serious concern about social weaving larvae observed near Rectory Farm. The letter is shared below and we will share responses as we receive them. Our aim with this campaign is to prevent threats to plant, animal life and especially trees from the moth larvae and advocate for urgent action from government agencies and local councils.
Dear Sir or Madam,
Subject: Social Weaving Larvae: Spread and Presence in Enfield Chase Green Belt
I write on behalf of Open Woods, a community-led environmental evidence-gathering initiative operating within the Enfield Chase area of the Metropolitan Green Belt, to formally notify the above agencies of the observed spread and presence of social weaving larvae and related gregarious, web-spinning caterpillar species across woodland and hedgerow trees in this protected landscape.
This letter requests urgent attention, survey, assessment and where necessary intervention from the relevant competent authorities.
1. Nature and Extent of the Observed Problem
The members of the Open Woods Community Project have recorded, with photographic and observational evidence, conspicuous silk webbing nests and associated larval colonies on a number of broadleaf tree species within the Enfield Chase green belt. Affected trees include, but may not be limited to, oak, hawthorn, blackthorn. The infestation appears to be spreading across multiple woodland parcels and hedgerow corridors within the EN2 postcode area.
The social nature of the larvae characterised by communal silk tent construction, gregarious feeding behaviour, and sequential defoliation of host branches poses a significant threat to tree health, biodiversity, and the ecological integrity of this protected open space. Left unaddressed, such infestations can cause severe defoliation, weaken trees and render them susceptible to secondary infections and bark pathogens, ultimately contributing to tree loss within the green belt. We bring your attention to the Rectory Farm area just off the Ridgeway where we have observed significant activity. This pest infestation is counter-productive to the Enfield Chase Restoration Project at Rectory Farm creating over 60 hectares of new public woodland and a threat to the newly planted trees close to the social weaving larvae. Evidence of the larvae can be found https://www.youtube.com/watch?v=0hODjJRB6UE and also within our reports for May 2026 https://www.openwoods.org/reports/rectory-farm-to-windrush-may-31-2026
2. Legal and Regulatory Framework
We draw your attention to the following legislative and regulatory provisions relevant to this notification:
• Plant Health Act 1967 — This Act confers upon the Forestry Commissioners the role of competent authority for the protection of forest trees and timber in Great Britain from pests and diseases, and grants powers to make orders for the control of timber pests. Section 2 of the Act enables relevant Ministers and the Forestry Commission to make statutory orders requiring the destruction or treatment of infested trees or material.
• Forestry Act 1967 — Section 1(4) requires the Forestry Commissioners, in exercising their functions, to comply with directions relating to the control of timber pests and diseases under the Plant Health Act 1967. The Commissioners hold a general duty to promote the establishment and maintenance of adequate reserves of growing trees in Great Britain.
• The Official Controls (Plant Health and Genetically Modified Organisms) (England) Regulations 2019 — These Regulations govern official controls relating to plant health in England. The Animal and Plant Health Agency (APHA) is the regulator responsible for plant health protection controls in England other than those regulated by the Forestry Commission.
• Environment Act 2021 — Part 6 of this Act introduces legally binding environmental targets and biodiversity net gain requirements. Local authorities and public bodies are under a duty to conserve and enhance biodiversity, and it is submitted that failure to address a significant invertebrate pest infestation spreading within a protected green belt is inconsistent with these duties.
• Town and Country Planning (Tree Preservation) (England) Regulations 2012 — The London Borough of Enfield holds statutory responsibilities in relation to tree preservation and the protection of trees in conservation areas and the green belt. We ask that the Council's Arboricultural Service liaises closely with national agencies in responding to this notification.
• National Planning Policy Framework (NPPF) 2023 — The NPPF places strong protections on the Metropolitan Green Belt and identifies protection of the natural environment, biodiversity, and the character of the landscape as material planning considerations. Any damage to the tree stock of Enfield Chase resulting from unchecked infestation would be contrary to these objectives.
3. Recommended Next Steps
We respectfully urge the relevant agencies to take the following steps as a matter of priority:
• Formal survey and assessment: Commission an urgent field survey by a qualified arboriculturist or Forest Research entomologist to identify the species, extent, distribution and severity of the infestation across the affected parcels of Enfield Chase.
• We request a report is raised on the the Forest Research TreeAlert online system. We request that these reports are escalated to the Tree Health Diagnostic and Advisory Service (THDAS) for formal diagnosis and a written response within the standard two-week window.
• Coordination between agencies: We request that Forest Research, the Forestry Commission (England), APHA, and the London Borough of Enfield Tree Management Service coordinate their response under the concordat arrangements established to govern multi-agency tree health interventions.
• Intervention and management plan: Where infestation is confirmed, a written management plan should be prepared and shared with detailing proposed treatment, removal or monitoring measures.
• Community engagement: Open Woods and the local community should be kept informed of findings, decisions and actions. We are willing to support ongoing monitoring and evidence gathering as part of a collaborative effort.
• Precautionary protection: Pending formal assessment, we request that steps are taken to prevent activities that might further stress affected trees, including postponement of any scheduled pruning or ground disturbance work in the immediate vicinity.
4. About the Open Woods Community Project
The Open Woods Community Project is a community environmental initiative dedicated to gathering and preserving evidence about the health, biodiversity, and ecological value of the woodland and open green spaces of Enfield Chase and its surroundings. Our work is carried out by two founders with the longer-term aspiration of training volunteers and local residents committed to protecting this irreplaceable green belt landscape for the benefit of the local community. We are grateful to the support of the Enfield Society who have enabled us to establish and develop methods with a view to longer term sustainability. Our pilot is now underway to collect photographic, observational and biological records which we make freely available to statutory bodies, researchers and the public. Our work complements and supports the surveillance activities of national bodies. We invite you to visit our project website for further information, evidence submitted to date, and to learn more about our community monitoring efforts: Open Woods Community Project: www.openwoods.org
5. Request for Formal Response
We respectfully request a formal written acknowledgement of this notification from each of the agencies named above within 14 days of receipt, together with confirmation of the steps that will be taken in response. Should any agency require further information, photographic evidence, or for us to accompany on-site visits to support their assessment, the Open Woods Community Project is pleased to assist. We are conscious that early detection and swift intervention are critical to preventing the spread of tree pests and diseases and to safeguarding the ecological, amenity, and landscape value of Enfield Chase. We trust that the agencies will treat this notification with the urgency it merits.
Yours faithfully,
Helen Moulinos
Co-Founder, Open Woods Community Project
