London and Berkshire people reminded about caterpillar pest in oak trees

People in parts of London and Berkshire are being reminded not to touch caterpillars of the oak processionary moth (OPM), which are beginning to emerge in oak trees in these areas.

They are also advised to keep children, pets and livestock away from the caterpillars and their nests, which can cause health problems, and to report any sightings.

Affected areas are several boroughs in West and South-West London, Bromley and Croydon in South London, Elmbridge in Surrey, and Pangbourne in Berkshire.

OPM caterpillars are a tree pest which was accidentally introduced to Britain. They feed on oak leaves, and in large numbers they can severely defoliate trees and leave them vulnerable to other pests and diseases.

Their tiny hairs contain a protein which can cause itchy skin rashes, eye and throat irritations and, occasionally, breathing difficulties, in people and animals. The hairs can be blown on the wind, and left in their nests in and under oak trees. The greatest risk period is May to July, although nests should not be approached at any time.

The Forestry Commission, Councils and land managers are tackling the pest with a carefully controlled programme of tree treatment and nest removal. Ian Gambles, the Forestry Commission's Director England, said that monitoring at the end of last year’s government-funded control operations showed signs of significant improvement, including:

• a 53% reduction in nest numbers, from 10,163 in 2012 to 4756;

• a slowdown in the rate of spread of the London outbreaks to 17 per cent compared with a 54 per cent increase the previous year; and

• no nests found in Pangbourne, Berkshire, compared with four in 2012 and 61 in 2011, indicating that the Pangbourne outbreak might be close to eradication.

Mr Gambles said the public had a valuable role to play in helping to control the pest by reporting sightings, but advised caution.

“We welcome reports of the caterpillars or their nests from the public or others, such as gardeners, tree surgeons and groundcare workers, who are out and about near oak trees,” he said.

“However, they should not try to remove the caterpillars or nests themselves. This needs to be carefully timed to be effective, and is most safely done by specially trained and equipped operators.”

Dr Yvonne Doyle, London Regional Director of Public Health England, endorsed this advice, saying:

“We strongly advise people not to touch or approach the caterpillars or their nests because of the health risks posed by the toxin-containing hairs. Pets can also be affected, and should be kept away as well. If you would like to know what these caterpillars look like, please see the Forestry Commission’s website for pictures.

“See a pharmacist for relief from milder skin or eye irritations following possible OPM contact, or consult a GP or NHS111 for more-serious reactions. Contact a vet if pets are affected.

“We have issued advice to local GPs and health professionals to help them identify when patients have been affected by the caterpillars and to advise them on appropriate treatment.”

Trees are treated by fully qualified operators under strict health, safety and environmental controls to ensure it is safe for people and animals.

• Sighting reports can be sent to the local council, or to the Forestry Commission via its Tree Alert app or on-line form available from www.forestry.gov.uk/opm, or by email to This email address is being protected from spambots. You need JavaScript enabled to view it..

• Health advice is available from the “Insects that bite or sting” area of the NHS Choices website, www.nhs.uk/livewell.

• Working on oak trees – Anyone having oak trees pruned or felled in the affected areas must contact the Forestry Commission’s Plant Health Service beforehand on This email address is being protected from spambots. You need JavaScript enabled to view it. or 0300 067 5155 for advice about safe removal of the material.

Further information is available from www.forestry.gov.uk/opm

What we know and don’t know about the physical benefits of trees and where are the gaps in research

Professor Roland Ennos, describes how the focus of this gap-fill research work undertaken in association with the Trees and Design Action Group (TDAG) and supported by Fund4Trees identifies the current state of knowledge of three key physical areas which can be influenced by the presence of trees. The research also highlights areas where more research could be beneficial. The target audience for this research paper are those involved in policy, management/protection, design and delivery of urban trees.

“We have focused on three key areas:

• Carbon storage and sequestration: this has been researched and written up in the agreed format.
• Cooling: this has been researched and split up into 3 separate benefits: local cooling of people; local cooling of buildings; and regional cooling and urban heat island reduction. We’ve finished all the text for this and just need a few diagrams and references.
• Flooding: work has been begun in this area.

The other major issue to consider is reduction of pollution but this would require specific expertise in this area to investigate. As far as noise reduction is concerned, this is not something trees are actually good at, and reduction in wind is far too difficult to quantify. We propose to approach Landscape and Urban Planning about publishing our reviews.”

Martin Kelly, TDAG Chair and Land Planning Director at Capita Property and Infrastructure, commented that “this is a very important step for urban trees. As practitioners it is vital that we work with evidence based research in order to make appropriate long-term decisions which are what is required if we are to have an effective well-distributed urban forest for the future benefit of our towns and cities. TDAG thanks both Fund4Trees for financial support and Professor Ennos and Dr Asrafur Rahman for their expertise in making this important piece of work possible."

Next Ride4Research Ride: Sunday - 14th September

A circular 25m bike ride of two halves, starting from the AA’s 50th national conference venue the Royal Holloway College, through the leafy back lanes of Chobham Common (National Nature Reserve & SSI) to the winding paths within Windsor Great Park.

The ride will join the AA Ancient Tree Management Field Day (led by Ted Green & Bill Cathcart) in the early afternoon before returning to the College.

More details to follow in the AA e-newsletter and on the F4T website: http://fund4trees.org.uk

Arboriculture Association Conference Attracts Global Speaker Roster and Senior Health Figures

‘Applied Arboriculture: Healthy Trees, Healthy People’

14th - 17th September, Royal Holloway, Egham, Surrey.

Excitement is building as the 2014 Arboricultural Association adds the finishing touches to its three day Amenity Conference in September. The event takes place at the prestigious Royal Holloway in Surrey and has attracted enormous interest as it focuses on some of the key issues associated with the benefits of healthy trees and healthy people.

Baroness Fookes of Plymouth will deliver the opening conference address. The health perspective will be represented by, amongst others, Sir Richard Thompson (recent past president of Royal College of Physicians) and Professor Nicola Spence (Chief Plant Officer, DEFRA).

Simon Richmond Conference Manager comments on the build up to the conference:

‘This year’s conference is breaking records all round. 2014 marks the 50th anniversary of the establishment of the Association and combined with such a topical theme we have attracted unrivalled interest from presenters and delegates. 36 speakers will be taking to the podium representing the very latest opinions, research and commentary. We have attracted 13 international speakers from as far afield as Australia and the Czech Republic who will provide new insights into the key topics of tree health and human well-being. This is not an event to be missed.’

The Principal Conference Themes

“ …an exceptional opportunity to learn, collaborate and share with global opinion makers and thought leaders..”

• Tree Populations: Climate change and biodiversity
• Managing Tree Health
• Trees and Human Health
• Challenging Established Practices
• Delivering Health and Well-being with Trees

Read more: Arboriculture Association Conference Attracts Global Speaker Roster and Senior Health Figures