JCA held a contract with an estates manager for all over North Yorkshire and at this particular site in York, our role was to survey the trees and provide recommendations where necessary to ensure that the risk to visitors and the heritage structures at each site, as a result of tree failure or damage, was kept as low as reasonably practicable.
During the first year’s surveying, the main task was to identify the trees on each site, record the relevant data (species, age class, stem diameter, canopy spread), make specific comments about each tree with regards to e.g., form, pruning history, note any defects and assess their physiological and structural condition. Where defects were identified which presented a potential hazard or where general maintenance was considered necessary, appropriate recommendations were prescribed, including tree felling or pruning.
The trees on these sites were generally considered important to the aesthetic value of the site. As such, whilst the safety to the public and the Heritage structures was paramount, on occasions it was possible to retain trees rather than felling them by installing fencing, ensuring the public remained out of potential harms way.
Each tree surveyed was individually tagged to assist with on site identification. The trees at each site are surveyed annually over a period of seven years. Each annual survey takes place at a different time of year so that the trees are viewed and surveyed at different times of the year. This is beneficial as it allows the trees to be assessed in greater detail. For example, each tree is surveyed when it is in full leaf, so that the vitality and vigour of the foliage can be assessed. When the same tree is surveyed in winter, this allows for the branches and limbs and overall crown structure to be more clearly viewed (with the foliage no longer present on the deciduous trees) and any defects identified. When surveyed in autumn, the presence of any fungi can be more easily identified and symptoms of ill health, such as early leaf drop, can be better determined.
If an issue arises regarding a tree, records of the management of this tree through the years can be easily accessed, providing proof of a responsible tree safety management programme.