Planting trees in urban areas has a number of environmental, social and ecological benefits. Street trees:
- Offer cooling effects due to shading and evapotranspiration from the canopy
- Help to improve air quality due to production of oxygen and adsoprtion of ari-borne pollutants such as polycyclic aromatic hydrocarbons (PAHs) and by mitigating carbon emissions
- Improve aesthetics and quality of place
- Improve health and well-being
- Encourage biodiversity due to provision of habitats.
Further indirect benefits include the reduction in building energy-use due to reduced air conditioning in summer and reduction in heating in winter due to sheltering buildings from sun and wind.
The tree species that are chosen for urban areas all exhibit characteristics associated with urban suitability, such as tolerance of harsh conditions. All tree plantings are site specific and careful species selection represents a fundamental part of any good urban forestry project.
There are a number of street tree planting schemes across the UK, including the Mayors Street Tree programme which aims to plant 100-400 trees per area in 40 'Priority Areas' of London. Further information on this can be obtained from Mayors Street Trees and Street tree initiatives.