We have completed a wide range of tree surgery work in school premises in the Hertfordshire area and also tree surgery in Baldock. During a site visit to the Knights Templar School in Baldock, a large number of Ganoderma brackets were identified on a very large, mature Beech tree. Ganoderma is a type of wood decaying fungus that degrades and breaks down the lignin and cellulose. It’s most often found in the butt and roots of the tree. This indicated that the condition of the tree needed looking in to further as there was decay present in the base of the trunk
We recommended that the base of the tree was scanned using “sonic tomography”. Sensors are placed around the trunk and sound waves travel between the sensors. The velocity of soundwaves is measured through a number of sensors on the tree determining the density of the wood and whether it is decayed. The technology interprets this information as an image which shows areas of rotten and sound wood. This would give us a much more in depth idea regarding the condition of the tree and its trunk
The scan showed that very little sound wood remained in the base of the tree. We used the “Forbes-Laird THREAT analysis” approach. This takes into account defects of the tree, what is nearby, and what impact this would have if the tree failed – we gave the tree a risk score. The tree was in poor condition, close to the school and the consequence of it falling would have been dire. The resulting score meant that the tree had to be taken down within 7 days and that area of the school could not be used until that point
A 5 day notice was given to North Herts District Council to fell the tree. The area of the school adjacent was evacuated until the tree was removed due to the danger that it represented
The tree was taken down, with the use of a crane, and cleared away leaving the school tidy and safe. This meant that the children were able to return to that area of the school without cause for concern. The tree was “sectional felled”. This means that rather than felling the tree in one go, we removed the tree branch by branch. Many sections were lowered down on ropes in a controlled manner. This meant that they did not come into contact with surrounding buildings
The trunk was lifted away onto a “HIAB” lorry using a hydraulic lifting arm. The final section alone weighed in at 7 tonnes!
If the team hadn’t have taken down the tree, it would eventually have failed. Although this case was extreme, it demonstrates the importance of further investigation and evidence based intervention
The School have a duty of care and if they had not done the work. They may have left themselves vulnerable to a claim if the worst had happened
The Blue Tree Company offer a range of pruning services to make trees appropriate for their location including crown reductions, thinning and cutting away from buildings
The central part of the area is in a Conservation Area and can have an impact on the required process for tree surgery in Baldock. As such, notice of intended works needs to be sent through to North Herts District Council; this is a 6 week process. We can handle all of the paperwork on our clients’ behalf as part of the service.