OPM Services: Protecting Your Oaks


Understanding Oak Processionary Moths

Oak Processionary Moth, commonly referred to as OPM, are not just your typical moths. Originating from southern Europe, these pests have migrated and established themselves in parts of the UK, becoming a significant concern for oak trees.

Life Cycle & Identification: The life cycle of OPM begins when they lay their eggs on oak tree branches. These eggs hatch into caterpillars, which are most active between April and June. These caterpillars are easily identifiable by their long, white hairs and their unique behavior of moving in a nose-to-tail procession, hence the name. As they mature, they build distinctive white, silken webbing nests on the trunks and branches of oak trees.

The Threat: While they might seem harmless, OPM caterpillars pose a dual threat. Firstly, they feed on the leaves of oak trees, which can lead to significant defoliation and weaken the tree, making it susceptible to diseases and other pests. Secondly, the tiny hairs on the caterpillars contain a toxin that can cause skin rashes, eye irritations, and respiratory issues in humans and animals upon contact.

REMOVAL: Before removing OPM nests, operatives will dress in full Personal Protective Equipment (PPE) including Hazmat suits, high-efficiency respiratory protection and eye protection.

Vacuum removal is the most efficient and safe method for removing nests, and dead and living caterpillars and their hairs. This method requires the trained team to use commercial vacuum cleaning equipment. Cleaners need to be capable of working to a high-efficiency particulate air filter (HEPA) specification. Filter specifications of H14 and H13 should meet OPM requirements.

opm (oak processionary moths) service

Spread & Impact:

Over the years, the spread of OPM in the UK has been facilitated by the movement of infested plants and the natural migration of adult moths. Their presence has had a notable impact, not just on the health of oak trees but also on public health and the broader ecosystem.



Why Addressing OPM Matters

Managing and controlling OPM infestations is crucial for several reasons:

Tree Health

Oak trees, with their majestic presence, are a testament to nature’s grandeur. However, their health can be compromised by OPM infestations. Effective OPM control is paramount, ensuring that these trees retain their vitality, stand tall, and continue to grace our landscapes for generations.


The seemingly innocuous OPM caterpillars carry a hidden danger. Their tiny hairs, when airborne, can become a health hazard. These hairs can cause skin irritations, and when inhaled, lead to respiratory discomfort. It’s essential to manage OPM to ensure the well-being of both people and animals.


Oak trees play a multifaceted role in our ecosystem. Beyond their aesthetic appeal, they offer habitats for diverse wildlife and act as natural air purifiers. By maintaining healthy oaks, we not only preserve these benefits but also contribute to a balanced and thriving environment.

OPM survey


Is OPM Affecting You?

Anyone with oak trees on their property, especially in affected regions, should be vigilant. This includes:


Oak trees enhance gardens, offering nature’s touch to homes. However, with Oak Processionary Moths (OPM) around, these oaks face threats. Homeowners must be vigilant to protect their trees and family.

Schools & Institutions

Schools and educational institutions with oak trees on their grounds need to manage OPM to safeguard the students, staff, and visitors from the health risks posed by these pests.

Land Managers & Local Authorities

Many educational campuses boast oak trees, enhancing their green spaces. It’s vital for institutions to monitor and address OPM, ensuring a safe environment for students and staff alike.


Landscaped areas elevate business premises. However, oak trees in these spaces can attract OPM. Businesses should prioritise tree health, safeguarding their environment for employees and clients.


Protect Your Oaks Today

Don’t let OPM compromise the health of your oak trees. With Green Canopy’s expertise, ensure a safe and thriving environment for your oaks and those around them.