Thanks to all those who attended our recent Trees in Crisis conference and helped make it a great success. Once again we hosted it in partnership with Royal Botanic Gardens Kew and hope those of you who took the lunchtime tour enjoyed the surroundings and the iconic trees.
Tony Kirkham, Head of the Arboretum at Royal Botanic Gardens at Kew welcomed the conference and gave an overview on Managing Threats to High Value Trees, reminding delegates that trees did not originate in nurseries, and that their local environment and management is fundamental to their health and longevity. We have to go to where trees have evolved looking at them in their natural ecosystems, such as old growth and savannah landscapes, to appreciate their likely needs in the unnatural situations we may place them – if we are to develop management practices to mimic their evolved conditions. While we can compensate in different (often costly) ways, declining tree health and reduced longevity often reflect the degree to which trees are ‘asked’ to function in non-natural environments. Their beauty and all they do to contribute to such places as arboreta and our landscapes demands that we have better understanding and investment in natural their processes.
In Kew Tony tries to achieve this through using wood chip around compacted trees, macerating rather than removing leaves, “letting our friends the earthworm to do the soil improvement work for us”. Look after them and we are more than half way there.
Neville Fay, Principal Consultant and Director of Treeworks Environmental Practice continued the conference setting the scene around issues relevant to an Integrated Vision of Tree Health and Disease. He considered that our trees are under unprecedented stresses, some dating from increased use of fertilisers, pesticides and herbicides and others from climate change effects, water abstraction, chemically altered environments (e.g. nitrification) and damaged soil ecosystems. He raised questions as to what triggers otherwise weak pathogens such as Massaria platani and some Phytophthoras in their natural habitats to behave differently.
He also discussed how Prof Brasier had conveyed the need to recognise there are serious threats facing human communities from biosecurity dangers due to globalisation, nursery imports and the unconscious spreading tree diseases through human traffic and movement of asymptomatic plant vectors.
Neville explored Massaria Disease of Plane, Acute Oak Decline and Canker Stain of Plane. The former, though more a problem to people than plane trees being only recently recognised in Britain. The latter having been introduced to Europe in WW2, have since caused 50,000 plane tree deaths and currently threaten 42,000 planes (P. orientalis) lining the Canal du Midi alone.
He commented that people, even including our own sector, are moving diseases round and finished stating that “our tree, soil and conservation sectors need to take a lead, joining with other sectors to counteract potentially catastrophic damage to the environment from new tree diseases – as they will be detrimental to human, political, economic and environmental interests, sleep walking through this is not an option”.
Paul Stamets presented the first keynote lecture on Solutions from the Underground: How mushrooms can help save the world.
Paul has written several mushroom related books, which are used as textbooks around the world contributing to improving understanding of the tree-fungi ecosystem. He described how it is impossible to understand how trees have evolved and function in their natural state without a deep and sensitive understanding of fungi and how they work above and below ground. His pioneering work in applied mycology has used fungi for bio-remediation of damaged soils, based on knowledge of anti –fungal, –bacterial and –viral properties of fungi he has demonstrated medicinal and curative preparations.
Paul gave a fascinating insight into the Agarikon (Fomitopsis Officinalis) mushroom which grows to enormous sizes, its fruiting body being decades old (and into the strangest of shapes) on and around old growth trees.
He also covered the relationship between termites, ants and other insects and fungi, sparking discussion and great interest.
Dr Alan Rayner, freelance naturalist, artist and communicator presented the second keynote lecture on Understanding the Tree as an Inclusional System: The hole way of thinking.
In misunderstanding space which we and all things are inseparable from, we make fundamental mistakes that lead to wrong decisions about the relationship between living things and their environment, and therefore how to understand factors connected to health and disease. “There is an inseparable link between life and death and nature and the eco system. Life and death are seen not as opposites, but as inseparable co-creative partners because tangible energetic form and intangible space are recognised to be distinct but mutually inclusive presence”.
He argued that “in an attempt to understand our living environment we have lost our connection with it.”
The only way back is to understand the meaning of inclusionality, how host space and its colonisation are attributes of one another – and so much more. This recognition helps establish a natural basis for engaging with health and disease models by helping humans to find a way back in to re-attuned state with their natural ecosystem, reducing conflict with their habitat.
Jim Smith, Project Development Manager of the Forestry Commission presented Tree Disease, Loss and Human Impacts: Challenges facing custodians of our tree heritage.
He focused on trees and their standing with our urban environments and it is fundamental that we consider “our interaction between trees and trees with people.” Demonstrating a slide of trees bent nearly double in supermarket car parks, he pointed out that urban environments are not naturally tree friendly. But to deal with this we need to integrate trees into our built environment more sympathetically with consideration to their natural system through wide engagement across disciplines.
Jim also announced that there would soon be the launch of the National Tree Safety Group’s (NTSG) report, Common Sense Tree Management. We need trees to be providing the ecosystem services that make cities a better place to live. Our urban forest planting programme needs to be sustainable if it is to provide future city generations with the same ecosystem services that we benefit from today.
Delegates Share Experience
After lunch Neville invited delegates to share their arboricultural experiences with the conference.
Neville had invited John and Maureen Bissell of Hazeleigh Wood, Maldon (who could not attend) to describe their experience of using charcoal as a form of AOD remediation. They claim to have successfully treated AOD woodland trees using charcoal kiln residue (dust and ash) placed around base of affected trees “for the rain to wash into the roots”. In their view oaks show AOD symptoms after being under stress (e.g. drought). A tree with bleeding lesions had weeping arrested after charcoal-treatment. They have similarly treated 60 – 70 trees with a reasonable success (though this is has not been documented) and regard the charcoal benefits of charcoal and ash not to be simple coincidence. They have saved charcoal burn residues for Treeworks to include in trials. The idea first came from a TV programme (Eldorado-the real gold of the Amazon) about how indigenous people instead of slash and burn incorporated charcoal into agriculture with beneficial results.
Jonathan Meares from City of London Open Space talked about AOD in Highgate Wood, where trees of predominantly woodland character with high general public use by local residents are being assessed and recorded with a view to improving understanding of patterns of symptoms relating to AOD, stress factors. They are initiating remediation measures to improve growing conditions, improve light to affected trees, monitoring tree response for indicators of improvement.
Dr Glynn Percival talked about pest disease control and alternatives to it. He argued for treating the patient not disease, that pest and disease control is demanding, though without there being a “magic bullet”. Conventional pest and disease control and management strategies focus on plant protection techniques, relying heavily on treating pathogens with biological or chemical agents. However, management strategies designed to increase tree vitality will improve capacity for disease self recovery – mulching, fertilization and soil decompaction represent integrated replicable approaches for improving tree vitality, aimed to alleviate stress and improving resilience, recovery and longevity. These are important compared to strategies that fail to deal with assessing and alleviating stress related factors that pre-dispose trees to pests and disease.
Richard Page, Business Development Manager for Laverstoke Park Laboratory explained that given the underlying importance of soil ecosystems, LPL’s interest is in understanding and maintaining healthy soil food webs. There’s is an organic approach to soil health and therefore plant care. LPL has partnered Treeworks in its study of soil condition at The Royal Parks (TRP) exploring remedial treatments for AOD affected trees. When there’s a dislocation between ho we understand the soil and ecology, detrimentally affects plant health and resilience. Treatment of the plant which ignores functioning soil ecosystems is superficial with potentially disastrous results. Working in collaboration with Treeworks and TRP, Richard hopes that through learning about how organic amendments, including compost teas, can beneficially affect tree health, protocols for cost-effective AOD control will be established.
Dave Lofthouse, Chair of London Tree Officers Association (LTOA) warned of the increased emphasis required to make Biosecurity effective. There are real problems in developing coordinated systems for treating Oak Processionary Moth (OPM) and with the Emeralds Ash Borer now in Paris and could be carried here tomorrow in someone’s car, we need to ramp up our systems, communicate the issues at a political level and engage across relevant sectors to ensure our urban and national forest species populations are protected.
Please leave your comments below on how you found the conference and what you’d like to see going forward.
“The 2011 Trees in Crisis conference represents a new milestone in understanding that trees are complex communities, undergoing constant change, and that the role of fungi is critical for sustaining their health. By bringing together scientists, arborists and policy makers, this conference will be viewed for many years to come as historic. It is only through cooperation at all levels that we will be able to ensure future generations enjoy the many benefits trees and forests provide to people and planet.”
Photos by Edward Parker