Acute Oak Decline

Acute Oak Decline (AOD) affects native oak trees in Britain and can cause their death.

It is a relatively new disease that first made its presence in the UK 30-35 years ago. Acute Oak Decline mostly effects pedunculate or English oak (Quercus robur) and sessile oak (Quercus petraea).

Trees that are affected by AOD produce vertical, weeping fissures that ooze black fluid down their trunks. A lesion then forms in the live tissue beneath this "stem bleed". This is a sign of decay and many trees die 4-6 year after the onset of symptoms.

Woodland Heritage have helped launch the Action Oak initiative to help raise awareness and research this killer disease. You can make a donation directly to us, or Action Oak.

Make a Donation

Action Oak

This campaign to protect oak trees - was officially launched at the RHS Chelsea Flower Show 2018 by Biosecurity Minister Lord Gardiner.

Woodland Heritage is a founding member of the Action Oak initiative which also includes the Woodland Trust, National Trust, the Duchy of Cornwall, Forest Research, Royal Botanical Gardens Kew, the Forestry Commission, the Northern Ireland Forest Service, Defra and the Scottish and Welsh Governments.

The Action Oak initiative is seeking to raise £15 million for research and monitoring to help safeguard the 121 million oaks in UK woodlands.

Action Oak is supported by Woodland Heritage's Patron, HRH, The Prince of Wales. In February, 2018, HRH, The Prince of Wales held a top-level, cross-sector summit to discuss Xylella plant disease threat and biosecurity at his residence in Gloucestershire, Highgrove. 

Celebrating our Oaks : Foreword by Dame Judi Dench

This wonderful book features ‘tree-mendous’ photographs from the ‘Celebrating Our Oaks’ category in International Garden Photographer of the Year (IGPOTY) competition, including ‘Oak Sunrise’ by Alan Price. Plus exclusive contributions from celebrities including Joanna Lumley, Jon Snow and Alan Titchmarsh.

Proceeds from the sale of the book will be go direct to Action Oak to fund research and monitoring, helping to protect our oaks and ensure their place in the British landscape for future generations.

Buy Now


Supporting research into Acute Oak Decline

This film documents the challenge posed by Acute Oak Decline (AOD) to British oak trees. Entitled ‘Saving our Oak’, the film can be viewed below. The film gives thanks to past supporters showing snapshots of the research that their donations have made possible, but also highlights that despite great progress made, so much more needs to be learned, for which another urgent appeal is underway. (A 3 minute version of the films can be viewed here.)

A priority for Woodland Heritage is to support all ongoing scientific research into the threats to our oaks. Woodland Heritage is a founding member of the Action Oak initiative.

Attending an event to launch the film, Minister for Biosecurity Lord Gardiner of Kimble said:

“This film highlights some of the crucial research that is ongoing to counter Acute Oak Decline.

“This disease puts the majestic oak, our national tree, in jeopardy. It is vital that we develop further our knowledge of how to unlock the disease’s defences and tackle this threat.”

Acute Oak Decline (AOD) is a condition affecting several thousand oak trees, mostly across East Anglia, the Midlands and Southern England as far west as Somerset. It affects both of Britain’s native oak species: pedunculate or ‘English’ oak (Quercus robur) and sessile oak (Quercus petraea) as well as other species of oak.

AOD is characterised visually by dark fluid oozing from cracks in the bark, rapid decline of the tree, and the eventual death of affected trees. Death can occur within four or five years of symptoms first becoming visible. Many affected trees also have characteristically D-shaped exit holes of the buprestid, or oak jewel beetle, in the bark.

Acute Oak Decline is killing our native British oaks, here are the signs of AOD:

Donate to AOD Research

Woodland Heritage’s Chairman of Trustees, Lewis Scott said: “As with so much linking Woodland Heritage with the challenge of Acute Oak Decline, and developing management strategies to protect our oak, this film was the brainchild of the charity’s past Chairman and fellow Co-Founder of Woodland Heritage, Peter Goodwin. From the moment that Peter became aware of the threat that AOD posed to his beloved oak tree, now a decade or so ago, Peter headed a relentless campaign to highlight the risks and raise funds to help support research into understanding the causes and managing the problem. He was always the first to promote what could and should be done to reduce the threats; he was always focused on acting and not talking, with the results showing themselves so clearly in this inspirational film”.

The story told in ‘Saving our Oak’ is one of partnerships and collaboration towards a shared objective. Peter used his energy and vision to highlight the plight of the oak and to persuade donors to help this wonderful, iconic tree have a more secure future. But he left the science to Forest Research to co-ordinate, carry out and direct, always working with Dr Sandra Denman, who had shared Peter’s concerns about AOD from the outset.

“Combining the expertise and resources at Forest Research with new ones that we were able to harness at universities and research organisations thanks to the money that Peter secured, this has been such an inspirational example of a private-public partnership working to great effect”, said Dr Sandra Denman. “The special opportunity that the charitable funding afforded us was to be nimble in response to research needs, able to widen our collective knowledge and better understand, and so manage this disease, in the future”.

Many of the scientists involved in the research are doctoral or post-doctoral researchers and their studies are showcased in the film using a holistic multi-disciplinary approach tackling topics as diverse as predisposition, soils, biogeochemistry, tree genetics and metabolomics, dendrochronology and chemical ecology, which are the factors that are increasingly recognised as contributing to the spread of AOD.

“It takes time and resource to carry out research that leads to greater scientific understanding and practical solutions, but the investment that Woodland Heritage and associated charities have made in this are starting to yield important results that are vital stepping stones to the solutions. Our future research programme lays out a path that we believe will help AOD to be further understood and better managed”, added Dr Denman.

Over £2m has been raised so far by Woodland Heritage towards research into AOD, but further studies to a value in excess of £1m are needed. To help these get underway, donations are being sought towards Woodland Heritage’s AOD Appeal and can be made above.


Support Research into AOD 

We need your help to continue to support research into Acute Oak Decline!

Join Woodland Heritage today and help Woodland Heritage raise awareness of Acute Oak Decline (AOD) and support research into this disease that is killing British oaks.

The special opportunity that the charitable funding afforded us was to be nimble in response to research needs

Dr Sandra Denman

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