13th September 2024
Many of the things for which urban trees offer us protection are at the same time threats to the tree themselves.
Urban trees suffer from:
- constricted and compacted soil, especially where they share the soil with pipes, drains and foundations, and where the soil is heavily trafficked by feet and wheels
- Damage to roots caused by excavations, damage to branches caused by high vehicles
- Strong wonders where buildings form wind tunnels
- Extremes of heat and cold, as well as ‘burns’ when sunlight is reflected off glass surfaces onto their leaves
- Air pollution affecting their leaves and bark
- Water-born pollution affecting the whole tree
- Artificial light which can disrupt normal photosynthesis, and disrupt the signals by which the tree knows when to sprout leaves in the spring and shed them in the autumn.
- Lack of light because of shading from tall buildings
- Lack of water especially where hard surfaces channel rain water away into drains
The first years of a newly planted urban tree are critical. They need to be kept well watered, their root space kept clear of weeds and their trunk kept free of abrasive damage. GreenBlue offers some useful advice – https://greenblue.com/gb/who-is-responsible-for-maintaining-our-public-trees/
Urban tree stress https://www.mdpi.com/1999-4907/11/9/932
The Green Tau 