Treeworks Environmental Practice Conference – Trees: the key to climate proofing our cities
Click Here to Comment (scroll to bottom of the page)
Temperatures in UK cities are predicted to rise by 3–7°C by the end of the century. Research indicates that a 10% increase in urban tree cover would completely neutralise this impact. According to the Trees in Towns II study trees are being lost at an alarming rate and urban deforestation is offering a hot future for city life.
With better co-ordination, within existing government guidance and management mechanisms, it is possible to achieve the level of canopy cover that will make the difference. This requires a strategy that, wherever possible, all large trees are conserved and planning and design ensures that we grow trees successfully to become big trees with big canopies.
This pioneering conference brought together a wide range of speakers to explore practical possibilities to reverse tree loss within the current planning framework. Our aim is to drive an initiative to achieve the required canopy increase. This can be done but only through the widest possible involvement between all relevant stakeholders, professions, government organisations, citizens groups, etc.
Please continue to provide us with your advice and ideas by using the comment box below. I invite you to become stake holders in this process by contributing to the blog.
Neville Fay, Principal Consultant Treework Environmental Practice
Forestry Commission England
I hope that I reflect the views of other attendees when I congratulate you on an excellent conference. It marked a milestone in bringing scientists and practitioners together to promote the benefits of trees and woodland in adapting the urban environment to climate change – in particular, rising temperatures compounded by the urban heat island effect
We heard that to achieve our objectives a number of actions and outcomes are needed:
·Leadership and focus on this agenda to encourage a more strategic approach for looking at the urban treed resource as a whole;
·An appreciation of the value of street trees outweighing their currently perceived ‘nuisance factor’;
·An improved understanding of the condition and extent of the urban tree resource;
·Greater awareness and understanding of risk and closer collaboration with the construction and insurance industries;
·A reversal in the decline of canopy cover in urban areas, particularly of ‘large canopy trees’;
·Increased planting of large canopy trees, where appropriate, replacing the recent trend to plant small trees that are unlikely to satisfy the future need for increased levels of shade;
·An acknowledgement of the need and financial resources for tree maintenance, reflecting their capital and social value;
·Incorporation of trees at an early design stage of new developments to ensure that the necessary infrastructure is in place to support the establishment and long-term retention of trees;
·Mainstreaming of trees in sustainable urban drainage schemes.
In England, Government policy is set out in ‘The Strategy for England’s Trees, Woods and Forests’ (ETWF). This establishes the principle of “the right tree in the right place” and recognises the broad range of social, economic and environmental benefits trees bring to society. The four letter word – TREE – in the title may seem insignificant, but its implications are more far-reaching and marks a significant broadening of the woodland and forestry agenda and, importantly, signals a new focus on street trees and urban woodland. It also creates many new and exciting challenges for the Forestry Commission in addressing the actions and outcomes outlined above. This of course is not done in isolation and we will continue to work with a wide range of key players such as the Department for Communities and Local Government (CLG), the Local Authorities, the aboricultural industry, CABE Space, Groundwork and the development sector to help drive this work forward.
On climate change specifically, our soon to be published ETWF Delivery Plan commits ‘To fully utilise street trees and woodland in minimising the impacts of climate change on our towns and cities’ as one its main objectives, with corresponding actions including reversing the decline in canopy cover. The Delivery Plan will be launched, formally, in the autumn and I hope that it will demonstrate our commitment to this issue.
In summing up this conference, Neville identified the need for leadership to achieve the outcomes that we all wish to see. The Forestry Commission, in partnership with many of those present at the workshop and others, will endeavour to provide this leadership so that urban trees continue to provide their full range of services and help to make our towns and cities of the future more comfortable and attractive places to live and work.
Comment by Mark Broadmeadow — 25 July 2008 @ 2:44 pm
Peter Thurman
The Thurman Consultancy
Along with the many other more obvious threats to our treescape, the potential loss of the art of designing with trees should be of equal concern.
We must move away from thinking of them as non-essential ‘cosmetic beautifiers’ and consider them as a vital and integrated component of both urban and rural design.
Everyone who plants trees – from architects and developers to local authorities and supermarket chains – should not expose themselves to the accusation of ‘cynical tokenism’.
Trees should be considered as bold, living, building blocks that provide vital green bulk rather than as dispensable trinkets.
They must be planted meaningfully and strategically to provide unity and structure, to define space, offer a degree of enclosure and most importantly, a sense of scale and proportion in the designed landscape. They have so much to offer.
Trees uplift our spirits. We have a primeval union with them. The better we use them the happier we will be.
Comment by Peter Thurman — 25 July 2008 @ 4:44 pm
Keith Sacre
Barcham trees
To achieve an increase in the canopy cover in urban areas it is not enough to just plant more shade trees. It has to be ensured that these young trees survive to provide the legacy desired.
The resources need to be made available to continue to build on the starter tree grown on the tree nursery, and this production process needs to be re-examined, to produce the mature specimens desired. Tree establishment has to be seen as a process and not something achieved, at a fixed moment in time, on some designated date, after planting has taken place.
This perceptual change has to be coupled with fresh standards and guidance notes, based on current research, endorsed by all those involved in the process, providing a framework for eventual success.
Comment by Keith Sacre — 25 July 2008 @ 5:00 pm
Jeremy Barrell
Barrel Tree Consultancy
Reversing the decreasing urban canopy cover trend; is it feasible?
From the very early days, one of the primary purposes of TEP XI was to provide as much information to as many people as possible in a bid to make connections that had been missed up until that point. The reasoning behind this was that the methods and ideas needed to reverse the decreasing UK urban canopy trend were out there scattered around, but they had never before been pulled together into one place for urban managers to review and contemplate. Of course, one day was not nearly enough time to do this comprehensively, but it was a start and an effective one at that. Making lots of very small connections to deliver a big idea is a counterintuitive concept because, superficially, it is hard to see how it works. But it does and the more ideas and the more people that can be thrown together into one melting pot, the greater the chance of the result that has been missing up to now. Increasing urban canopy cover is well within our reach if enough of those bright ideas and eureka moments can be stimulated through the facilitating framework that we are developing.
Here are two new connections that I made from the presentations that day:
·The potential of pollarding: Jim Smith has come up with a dramatic and innovative take on pollarding that I would never have even conceived if he had not enlightened us.
Of course, the conventional wisdom is that dramatically reducing big trees is a disaster and, from a purist perspective, I am sure we can all align to that idea. But, when we are facing the increasing loss of big trees because our present perception is that they cause much more disbenefits than benefits, then the idea of topping as a temporary stopgap suddenly starts to become a lot more attractive.
Because the value of big established trunks just sitting there waiting to explode into big trees within a few years will be immense when we need the benefits of big crowns without having to wait 30–40 years for them to grow to a size where they can make a difference. That is the problem with relying on new planting to provide the benefits; new trees take so long to establish and grow to a size where the big temperature and rainwater runoff buffering benefits kick in.
These established roots and trunks are a future resource that can be realised when the perceived balance of disbenefits against benefits tips in their favour. Of course, this can only be applied to certain species, oak, lime and plane being the most obvious, but it is still one small facet of a much bigger solution that deserves some serious consideration.
·Rainwater runoff buffering: John Young set out his vision of using trees as viable rainwater management buffering mechanisms, something we have all suspected would work but nobody has quite put the figures together to convince the engineers. He had not done it either but what he set out could be easily converted into a simple research project to establish precisely what the interception of various sized trees would be. Those figures could then be used to feed into the capacity calculations for new developments. Yet another significant benefit of trees that has been completely missed through a lack of focus and coordination but is emerging onto the radar because of this seminar. Through its capacity to adversely affect so many people, there is no doubt that flood management is one of the highest urban management priorities and trees can easily be an integral part of the emerging solutions. The connection here is that high priority equals money for research; the reasoning is there, the idea just needs to be kick-started, which is the next stage of the process that TEP XI started.
There are lots of other connections and ideas that will emerge from that day. We need to know about the ones we have missed to take this urban canopy initiative forward quickly and effectively.
Comment by Jeremy Barrell — 26 July 2008 @ 12:16 pm
John Young
Engineer, Edenvale Young Associations ltd
As a civil engineer involved on a day to day basis with evaluating the impact of climate change on flooding, The Key to Climate Proofing our Cities Conference was an interesting day in the smoke and I particularly liked Keith Sacre and Helga Fasbiner’s contributions.
For for me, an outsider, it was obvious that tree professionals were having a difficult time, grappling with climate change. The arb community is not alone in this respect. As a civil engineer working in flood and coastal defence business we have huge problems. Climate change may have a profound impact on the way we inhabit our cities and live by the coast. Too many issues are not well comprehended by professionals; less well understood by politicians and poorly appreciated by the general public.
So the question for large trees is, “what strategy for climate change?” Well for me it boils down to site and regional strategies much the same manner as the Suds.
Helga Fassbinder’s presentation was great and showed what can happen if communities are given the latitude to reclaim the urban environment. Community schemes are fantastic but we obviously need lots more trees.
Lots of large trees planted in appropriate locations can be used as a growing response to mitigate the impact of climate change on: the urban heat island: diffuse pollution and surface water run-off.
This is a climate change issue for public Authorities who must be in the vanguard educating, facilitating and planting large trees.
Comment by John Young — 26 July 2008 @ 12:19 pm
Climate change, CO2 content and microscopic particles pose problems, which find urban trees in completely different situations compared to the past.
We can no longer regard them as ‘cosmetic beautifiers’ but we have to consider them a vital and integrated component of livable and healthy cities.
In fact trees form machineries for conditioning urban climate and cleaning urban air which work independently and do not cost any electric energy.
In the long run the cost of maintaining trees is much lower and trees are more efficient in conditioning and purifying air than all other technological solutions.
Trees share these positive effects with other forms of urban greenery (like green roofs, pocket gardens, vertical gardens etc.) which fulfill a similar function. But the advantage of trees is: they are much more efficient because of the amount of leaves and the double use of space. (The upper part having climate functions; under the tree canopy are other urban functions).
To extend policies to increase the number of trees it is wise to cooperate with other groups that have similar aims to green the city.
Cooperation means:
- reinforcing all these initiatives by pooling, and
- forming a broad movement for another kind of design integrating greenery from the very beginning into the language of architecture and urban planning.
This is a condition for a final breakthrough to obtain more urban trees.
So let us unite in a campaign to attain that aim.
Prof. Dr. Helga Fassbinder
Amsterdam
Comment by Prof. Dr. Helga Fassbinder — 28 July 2008 @ 5:36 pm
Thanks for a really useful conference. Are there plans to make any of the presentations available online? I would be particularly interested in having some of the images available for use – they would be enormously useful in ‘selling’ the message about trees.
I am thinking particularly of Martin Kelly’s ‘missing trees’ images and the concept drawing of designing places for trees; Peter Thurman’s good and bad design examples; and John Young’s diagram of trees as self-contained SUDS. (We have access to the data behind Roland Ennos’s presentation but I am sure many people would really value the slides showing how 10% increase in tree cover will climate-pro0f urban areas…)
The i-trees project that Red Rose Forest and University of Manchester are developing should yield valuable hard evidence of what trees are doing for climate change – but it will probably be at least 2 years before we get any data. We will keep everyone posted!
Looking forward to Part 2 of the Conference! We would be happy to provide information on the development and use of Tree Canopy Surveys if that would be useful.
Mike Savage
Operations Manager, Red Rose Forest
Comment by Mike Savage — 29 July 2008 @ 10:24 am
An excellent conference and timely reminder to rejoin our individual efforts to plan ahead and make space for large urban trees.
The Chair’s comment was perhaps one of the most relevant and pointed remarks – ” where are the local authority CEO’s?” We need senior decision makers and other opinion formers to engage at a more strategic level, so let’s hope Part Two can include councillors, heads of regeneration, environment and public realm departments. I’d certainly be happy to encourage colleagues and managers in my own Authority.
Comment by Oliver Stutter — 31 July 2008 @ 10:25 am
I strongly support Oliver’s comment that the second conference on this theme should target professionals other than arboriculturists. Not only the sundry array of Chief execs, heads of regeneration etc, but also the designers and engineers who put together schemes that are long on hard surface but short on soil volumes.
Comment by Edmund Hopkins — 31 July 2008 @ 4:30 pm
One of the most valuable and informative days I’ve spent. To be presented with the papers at the start of the day is particularly helpful.
I would support most of the comments made so far.
I think it might be valuable to develop Jeremy’s point about interception rates to research whether certain species are more effective than others in reducing the volume or rates of run off – might this ultimately affect our species choice when designing new planting? As I write this my oaks have been devastated by tortrix and other moths, secondary growth has been hit by mildew, the horse chestnuts have all been got by the leaf miners, the squirrels are doing a fine job on beech and hornbeam and Oak Processionary moth is 400 yds from our boundary….. can anyone advise me what we should be planting in the future!!
Comment by Simon Richards — 31 July 2008 @ 6:16 pm
Trees have been identified as a key landscape element for making our cities of the future cooler, more pleasant and engaging places to live and work than would otherwise be the case in relation to the urban heat island effect. However, cities are not the natural environment for trees or indeed of people. The relationship between trees and the built environment is critical if we are to achieve the level of canopy cover required to really make a difference in terms of climate adaptation.
The limiting factor for achieving large landscape trees in cities is invariably how the buildings and infrastructure are designed and constructed and therefore able to accommodate the presence of these large long lived growing organisms. To be able to flourish and provide the benefits we know they are capable of delivering they require enough water, nutrients and soil capacity throughout their entire life cycle and not just what is provided in a new tree planting pit.
The urban forestry and arboricultural professions must persuade their colleagues who are responsible for the built enviroinment that they need to consult with them at the earliest opportunity in the preparation of designs so that the trees planted have the best possible chance of achieving their species potential in terms of size and scale without the requirement for intensive management. By their turn the built environment professionals need to develop a new culture of seeing trees as an integral element of their designs, an element that requires physical accommodation rather than constraint in terms of root and branch development.
Sound advice by the appropriate professional at the appropriate time is the cornerstone of deliverying trees as an adaptive response to climate change in cities, without this co-operative working delivered now it is questionable whether or not we will achieve the canopy cover required to ameliorate the expected impacts of climate change in the future.”
Comment by Jim Smith, London Tree and Woodland Framework Manager — 7 August 2008 @ 1:09 pm
I just found out about this conference – two months too late. I have set up a group called ‘More Trees for Bath and North East Somerset’. One campaign we are currently planning is to get our local authority to adopt a strategy like this to prepare for climate change. If anyone has any advice or can point me towards an authority that is currently setting an example in this area, I’d be very grateful. Also please let me know of any future events on this subject.
Comment by Adam Gretton — 21 September 2008 @ 3:02 pm
Our biggest enemy in this most important task is the insurance sector. I have been a technician for many U.K firms and have a broad experiance base both of clients needs and contractors morals etc.
I can without hessitation state quite catagoricaly that there are major contractors and consultants who have taken work by telling the clients what they want to hear and contractors who dont want to turn down the work or are too afraid to stand up and say this is wrong.
I know of one VERY high profile arboriculturist who was asked on aplying for a position with a top consultancy ” could you fell a tree that was the best specimen you have ever seen” this was considered a vital interview question.
Large oaks and other specimen trees are being removed daily from london and the suburbs on the “dodgy” claim of soil dessication. The reality is that to remove a 300year old oak tree is far cheaper than underpinning a house.
It is obvious to me that dessication of soils is only going to increase without the canopy and shade of our urban forest. a walk in a forest on a hot summers day in august confirms the simple truth of a trees capacity to cool the surface of the earth.
I believe changing the way trees are viewed from an insurance point of view needs to be changed most urgently, this is the area we are losing the most trees to and magnificent trees not just poor ones.
A T.P.O order should be absolute for specimen trees, no felling a no fell policy for subsidance. insurance cannot be allowed to underwrite its responsabilities by slaughtering the environment.
Comment by Antony croft — 26 September 2008 @ 10:14 pm
Waiting for a hearing in Oregon one day, one State Representative with an interest in trees and a few spare minutes asked me why we don’t have more trees than we do. Or why some trees don’t last longer.
The answer was along the lines that all the efforts locally are to plant more trees, but maybe just the beginnings for protecting the soil.
To get 10% more tree canopy cover, we may need to triple efforts protecting soil.
MDV
Oregon
Comment by M. D. Vaden - Portland Landscape & Trees — 15 October 2009 @ 4:28 pm