Urban trees: three million more by 2040
Each year London’s 8.4 million trees remove 2.4 million tonnes of air pollution, including carbon dioxide, dust and other gaseous toxins. That’s around a quarter of a tonne per resident, on top of the handy shade, flood prevention and visual benefits that they provide – not to say the positive impact on real estate capital values. And urban tree planting in the capital is on the rise, with former Mayor Boris Johnson claiming over 20,000 street trees planted in London over his eight year tenure, and the Forestry Commission funding another 84,000 in the capital alone.
Figure 1: London and Glasgow tree count compared with Barcelona
Source: Forestry Commission
And more widely, in England between 2010 and 2014 over 800,000 trees were planted on 3,300 sites, over 70% of which were in urban areas. City authorities are giving it a great deal of thought, as Bristol’s design guide shows. Even so, tree density in some UK cities is still short of that achieved in other European cities, such as Barcelona (Figure 1). However, if the same pace of urban tree planting experienced in English urban areas persists from now until 2040, then there will be another three million trees in our towns and cities by then.
And some cities have much greater ambitions than that. Manchester, for example, has a plan to plant three million trees in that city alone by the early 2040s – implying that the pace of planting will intensify.
Where street trees are threatened in mature urban areas, they can become extremely political, as the controversy over Sheffield City Council’s tree felling programme showed. So, alongside increased planting, we predict increased ‘tree rage’ ahead from protesters concerned about tree losses. As the city becomes greener, so will expectations that it stays green.