Trees can be damaged on construction sites by a number of means.
- Physical damage – Physical damage to the upper part of the tree, the bark and breaking branches. This will almost always lead to permanent damage to the tree and can often be fatal.
- Root Damage Severance – Trees are also damaged when root systems are not properly protected. Digging and trenching which are necessary to construct a building can have catastrophic implications to trees health and stability. 90% of the tree feeding roots (fine roots that absorb water and minerals) are located within the top 6″ – 12″ of soil. For this reason Tunnelling or hand digging is recommended if utilities are to be placed within the vicinity of the tree.
- Compaction – Compaction of soil caused by heavy machinery and storing of building materials around the tree reduces the amount of pore space within the soil. This not only inhibits root penetration and growth but also decreases the amount of oxygen required for healthy growth and function of the roots.
- Soil piling – Piling soil over roots during construction or landscaping will also have an adverse effect on the trees ability to absorb water and nutrients. Only a few extra inches of soil can prevent water getting to the feeding roots in the upper part of the root system. This will often lead to drought symptoms like dieback in the upper crown becoming evident.
When preparing reports for trees on development sites Brockwell Forestry and Tree Surgery follow the guidelines set out in British Standards 5837: 1991 Trees in relation to Construction. (Soon to be updated. Draft document out for consultation). Thi report identifies trees which are suitable for retention / removal, we give recommendations for any remedial works which may be required to trees that are to be retained and also give safe protection zones for the trees. We can also act as intermediaries during planning and development, liaising with the local authority planning department, architects and sub-contractors if required. Brockwell Forestry and Tree Surgery can also make interval site visits during construction to ensure standards are being met.