A greener capital - communities make their mark with 12,000 free trees from the Mayor of London and the Woodland Trust
Trees will be planted in a range of locations across the city - from parks and community gardens to allotments, housing associations, schools and youth centres - giving local people the opportunity to transform the places where they live, work and rest.
Boris Johnson, Mayor of London, said: ''The Woodland Trust is a key trunk of the RE:LEAF programme and I am delighted to be able to provide 12,000 trees to be planted across London. I want to increase the city's tree canopy and plant one tree for every Londoner by 2025.'
Over 60 groups will receive a small pack of 105 trees or a large pack of 420 trees. Each pack is available in three different themes: year-round colour, wildlife or wild harvest, all of which are ideal for planting as hedging and copses to fit best within neighbourhood spaces. Species in the packs support a variety of wildlife including songbirds such as starlings, blackbirds and mistle thrush. This is part of the Mayor's RE:LEAF campaign which aims to promote the capital's trees and to encourage more to be planted. The Mayor wants to increase London's tree cover from 20 percent to 25 per cent by 2025.
Trees play a vital role in urban areas, helping improve air quality, manage water and provide important shade and shelter for people and buildings. The UK has one of the world’s highest rates of childhood asthma however asthma rates among children aged four and five fell by a quarter for every additional 343 trees per square kilometre 1. Concrete surfaces in shade can be up to 20°C cooler than concrete in sun2, and trees can reduce surface water runoff by up to 60 per cent compared to asphalt 3. In London it is estimated that 3,200 ha of front gardens have been paved over, increasing the number of hard surfaces in the capital.
Victoria Hodson from the Woodland Trust added: "We are really delighted to be working with the Mayor of London to provide free trees for communities in the capital. Planting trees is a great way for local people to help transform their neighbourhoods; to grow fruits and food and provide new homes for wildlife. These 12,000 trees will make a real difference and we would like to help communities in the capital do even more. Throughout 2012, we are offering 2,500 free tree packs as part of our Jubilee Woods Project to celebrate Queen Elizabeth's Diamond Jubilee, and we would love more communities to get involved."
Part of a wider national scheme supported by Ibuyeco, the London tree packs are some of over 230,000 free trees being distributed to groups across the UK by the Woodland Trust this autumn. The community tree packs enable communities to take part in the Trust's Jubilee Woods project, which aims to plant 6 million trees by the end of 2012. With HRH The Princess Royal as patron, it is only one of a handful of projects to carry official Royal approval.
In February, the Trust is encouraging millions of people across the UK to come together and plant one million trees in one month to celebrate 60 years since The Queen's accession to the throne. Communities can plant in February by applying for one of 1,000 free packs available at www.jubileewoods.org.uk/treepacks . Applications for February packs close on Wednesday 7th December.
RE:LEAF is a partnership headed by the Mayor of London to create opportunities for Londoners, businesses and local communities to help protect London’s trees and increase London’s trees cover. London’s population is expected to increase to about 8.5 million by 2025. RE:LEAF is committed to increase tree cover by 5 per cent by 2025 – equating to one tree for every Londoner.
Working in partnership with the Forestry Commission and third sector organisations such as the Woodland Trust and Trees for Cities the Mayor is developing projects and initiatives to support Londoners to green the capital. RE:LEAF was launched by the Mayor at a mass tree planting in January 2011.For further information about the Mayor’s RE:LEAF London campaign please visit www.london.gov.uk/releaf-london
The Woodland Trust now offers a range of mechanisms to inspire and enable large organisations, schools, community groups and individuals to plant trees on their own land.
The Jubilee Woods project has The Queen's support - and HRH The Princess Royal as patron. It will commemorate the 2012 Diamond Jubilee, marking Queen Elizabeth's 60th year as monarch. Next to Queen Victoria in 1897, she is the only British sovereign ever to celebrate a Diamond Jubilee. The Woodland Trust is the UK’s leading woodland conservation charity. It has 300,000 members and supporters. Visit www.jubileewoods.org.uk for more details.
The Woodland Trust is the UK’s leading woodland conservation charity championing native woods and trees. It has more than 200,000 members and its three key aims are: i) to enable the creation of more native woods and places rich in trees ii) to protect native woods, trees and their wildlife for the future iii) to inspire everyone to enjoy and value woods and trees. Established in 1972, the Woodland Trust now has over 1,000 sites in its care covering approximately 20,000 hectares (50,000 acres). Access to its sites is free.
ibuyeco (www.ibuyeco.co.uk) was launched by the BGL Group Ltd on World Environment Day, 5th June 2007. In 2008 it won two industry awards. The BGL Group was founded in 1992 and has grown to become one of the UK’s leading personal lines insurance group’s.
1. Air quality
Trees and woodland improve air quality by adsorbing pollutants such as nitrogen dioxide and ozone, intercepting harmful particulates from smoke, pollen and dust and of course release oxygen through photosynthesis. This can help to alleviate the problems caused by chronic respiratory disease.
Although some trees produce pollen which can affect a proportion of hay fever sufferers, the overall benefits of trees to air quality respiratory health are overwhelmingly positive (Hewitt 2005). Research by the British Lung Foundation suggests that one in every seven people in the UK is affected by lung disease, almost 8 million people (British Lung Foundation, http://www.lunguk.org/media-andcampaigning/media-centre/lung-stats-and-facts/factsaboutrespiratorydisease.htm accessed 4th July 2011).
Trees will have a proportionately greater effect where they are close to sources of pollution and nearer to people who might be affected.
There is evidence that urban trees remove large amounts of air pollution and improve urban air quality (Nowak et al 2006). The UK has one of the world’s highest rates of childhood asthma, with about 15 per cent of children affected and a higher prevalence in lower socio economic groups in urban areas (Townshend 2007). Columbia University researchers found asthma rates among children aged four and five fell by a quarter for every additional 343 trees per square kilometre (Lovasi et al 2008).
Some tree species are better for air quality than others. Field maple, silver birch, elder and hawthorn are all small trees which are good for air quality. Some species emit biogenic volatile organic compounds (BVOCs) which can contribute to the generation of ground level ozone. These include oak and some species of willow – in many cases the size of these species also make them unsuitable as garden trees (Stewart et al 2002).
2. Urban heat island effect and shade
Increasing tree cover in urban areas can help mitigate the ‘urban heat island effect’. This occurs in towns and cities as the buildings, concrete and other hard surfaces such as roads act as giant storage heaters, absorbing heat during the day and releasing it at night. The resultant effects can be dramatic; on some days there is a difference of as much as 10oC between city centres and the surrounding areas (British cities ‘could be up to 10oC hotter than countryside by 2100’, Daily Telegraph online http://www.telegraph.co.uk/earth/earthnews/5303682/British-cities-could-be-up-to-10C-hotter-than-countryside-by-2100.html., accessed 4th July 2011) Projections for our changing climate suggest urban heat island effect will get markedly worse.
The problem is exacerbated by a lack of green space. Green space and trees in particular, provide both direct cooling from shade and reduce the ambient temperature through the cooling effect of evaporation and transpiration from the soil and plant leaves.
The impact on health of urban heat islands is two-fold; firstly higher temperatures increase ground level ozone, exacerbating the symptoms of chronic respiratory conditions. Secondly prolonged high temperature can precipitate cardiovascular or respiratory failure or dehydration, particularly amongst the elderly, very young or chronically ill (Bhattachary 2003). In the 2003 summer heat wave over 2,000 people died in Britain alone and more than 50,000 died across Europe.
Preliminary results from the itrees project, collaboration between Red Rose Community Forest and Manchester University, suggest that;
Concrete surfaces in tree shade can be up to 20°C cooler than concrete in sun.
Tree shade can cool people by up to 7°C on hot days.
Research using computer modelling has shown how increasing urban green space can mitigate urban heat island effect. Without any increase in green space, by 2050 the temperature in Manchester is projected to rise by 3oC. However if the amount of green space increases by just 10 per cent then the effects of climate change on increasing surface temperatures could potentially be mitigated. However, reducing tree cover by the same percentage could lead to an increase of 8.2oC under some scenarios (Handley and Carter, 2006).
Providing direct shade in gardens reduces the risks from UV radiation (Heisler and Grant, 2000). Children’s’ skin is more sensitive to UV damage and the amount of sun exposure during childhood is thought to increase the risk of developing skin cancer in adult life. Shading is particularly important in gardens and where children play.
Radiant heat is also more important in terms of comfort than air temperature per se. Tree shading reduces the radiant temperature by up to 80C greatly increasing human comfort (Ennos. 2010).
3. Trees and water
Recent years have seen an increase in flooding. Many factors contribute to this. Clearly heavy and prolonged rainfall is a primary cause, and with climate change the occasions on which we suffer a deluge have increased UK Climate change projections (UK Climate Projections) and are likely to increase further. In towns and cities the increase in hard surfaces, unable to absorb rainfall, often mean drains are overwhelmed and water quickly collects on the surface rushing down streets and over paved areas. In London it is estimated that 3,200 ha of front gardens have been paved, and in Leeds an estimated 75 per cent of the increase in impervious surfaces that has occurred from 1971 to 2004 is a result of the paving of front gardens (Davies, 2011).
The Pitt Review following the 2007 flooding identified the paving over of front and rear gardens as having a major impact on drainage of surface water in towns and cities around two thirds of all the flooding in 2007 was as a result of surface water. The insurance cost of the 2007 floods was thought to have been around £3 billion, but the Environment Agency expect the regular annual cost of damage to property alone to be in excess of £1 billion. When the cost of further disruption, damage to infrastructure and loss of business is added this increases to £2.5 billion and could rise to £4 billion by 2035 (Environment Agency).
More trees in gardens could contribute to reducing the risk of flooding, and in particular surface water flooding, which threatens up to 3.8 million homes in the UK. Trees intercept rain and increase infiltration of water into the soil.
The potential for trees in managing flood risk was recognised in the Natural Environment White Paper for England (DEFRA 2011). Trees can decrease the rate at which rainfall reaches the ground and runs off into drains. This allows more time for the natural and man-made drainage system to take the water away, and can reduce the likelihood or severity of surface water inundating homes.
Interception by trees in urban areas can be critical in reducing the pressure on the drainage system (Gill, 2009) and lowering the risk of surface water flooding. Slowing the flow increases the possibility of infiltration and the ability of drains to take away any excess water.
Preliminary results from research by the University of Manchester has shown that trees can reduce surface water runoff by up to 60 per cent compared to asphalt (Armson et al 2011). The reduction in runoff, slowing the rate at which rainfall reaches the ground, increases the possibility of infiltration and the ability of engineered drains to take away any excess water.
When combined with other measures as part of sustainable urban drainage schemes, trees have an important role to play in consideration of flood risk.
Recent years have also seen a decline in the numbers of trees planted in urban areas which, combined with a loss of trees planted during the Victorian era, should send a warning signal about the future for urban tree cover (Britt and Johnston, 2008).
This press release is presented for your information only.
Full Disclosure Statement: The GREEN (LIVING) REVIEW received no compensation for any component of this article.
