Here at agb Environmental we are always on the lookout for new techniques to produce accurate results. Firing a laser at a tree doesn’t sound like the best way to help protect it from development, but that’s what was needed for one site in Chelsea recently.
Normally tree surveying involves little more than a tape measure and pen to capture the vital statistics. For this site, a small but potentially controversial development was proposed, entirely beneath the crown of a large, impressive street tree! The challenge was to demonstrate convincingly that the tree would not be compromised.
Due to the development being wholly beneath the crown of the tree, it required a much more accurate and extensive survey of the tree’s main branch spread than would normally be the case. We wanted to be able to plot the new building against this, showing if and where any branches would need to be removed. A few branches headed directly over the site, raising concern they would conflict with the design.
We contacted a specialist survey company and arranged for them to carry out a 3D laser survey. The level of detail they could capture was amazing – down to individual twigs and leaves, if we wanted, although we’d have to hope for a day free from any wind! Not needing that level of detail, we opted for the main scaffold limbs and the overall extent of the crown.
The images were available shortly after the survey and once we had plotted the development we could clearly see there was more room than initially hoped for. We were able to produce both plan and cross-sections, showing where the building would be in relation to the tree’s branches and crown.
Other than the removal of a few small areas of twiggy growth, no pruning would be required, demonstrating that the tree’s crown would remain unchanged. That just left the small challenge of building entirely within the tree’s roots, something that even lasers beams couldn’t help us with.
If you have a development that may require an arboricultural survey please contact Richard, our Principal Arboriculturalist on firstname.lastname@example.org or 01638 663226.