Introduction
Arboraeration were asked to investigate damage to a driveway that was suspected to have been caused by a group of neighbouring Pine (Pinus sylvestris) trees or an Oak (Quercus Robur) tree on the clients property that had been removed previously. It was Important to investigate and discover the cause of the damage prior to deciding on or attempting mitigation measures because if the damage was being caused by the removed tree it will not get any worse and the roots can be removed once the driveway is repaired.
Investigations
It was decided that we could cut holes into the driveway where the damage was being caused and airspade down until we discovered the roots that are damaging the driveway. The roots were found approximately 30cm below the depth, small samples were collected from the roots causing the damage and DNA tested to determine their species.
The DNA test results concluded that the roots that caused the driveway damage were coming from the neighbouring Pine trees. This meant that even if the damaged driveway was repaired, the conflict is still there, and the damage would continue.
Mitigation options:
It was decided with the client that we would excavate a trench on the edge of their driveway, adjacent to an area of shrubs and next to the area that the damage was being caused. We used an airspade tool to excavate the trench so that we could see the roots that were encroaching and prune them in the best way possible without causing any damage or pulling the remaining root system out of the ground.
Once excavated we are then able to carefully root prune any of the root system that is coming into conflict with the driveway, or in the case of smaller roots that are flexible they can be manipulated away from the area that the root barrier is to be installed.
Following the preparation the root barrier was installed, we used a product from Green Blue Urban (https://greenblue.com/gb/) called a Re-Root 1000. This is a 1m tall plastic barrier that is constructed from heavy duty, recycled HDPE Plastic. This root barrier will prevent any further roots from encroaching into the driveway moving forwards.
