Emmanuel College
Detailed Tree Inspection of the Xerxes Plane
ARBORICULTURE
Client ​
Emmanuel College
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Project Type
University college ​
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Following a pledge of funds to provide special care for a particularly notable tree, Emmanuel College approached TMA and asked for a proposal with regard to providing an enhanced level of care and value, whilst ensuring that the donor would have visibility of the benefit of the donation, despite no longer residing at the College. TMA proposed a suite of methods to assess the health and structure of the tree, provide an enhanced level of report and collaborated with Arb Innovators Ltd to simultaneously create a visualisation of the tree for the wider audience, including the donor.
Ground Level Scan
3D Models
Overview
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Emmanuel College maintains around 9 acres of historic garden in central Cambridge. One particular tree, an oriental plane (Platanus x orientalis) known as the ‘Xerxes plane’ sits to the northern edge of the site, and is a notable tree to all visitors and residents of the college. The College received a pledge of funds intended specifically for the care of this tree, and following some initial discussion regarding how this could be used effectively, TMA suggested a way the funds could be used to provide a high level of data, whilst adding value for the College in a way that the benefactor could be part of.
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Challenge
Historic gardens regularly find themselves the recipients of donated trees and benches, as a way to commemorate members or times. Whilst this is usually good, such gardens often have limited space for garden expansion, and so in this case, the proposal of funds for an existing tree was a refreshing change. However, with the benefactor no longer local, we needed to provide a service that not only benefited the tree and College, but also provided value to those further afield.
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​Approach
We proposed and carried out an advanced-level tree risk assessment, accurately measuring the tree and recording observations regarding the health and structural condition of the tree. Handheld LiDAR data of the tree stem was captured and submitted to AdBian®, along with photographic data to provide an enhanced level of report regarding wind loading, biomechanics and beam modelling, to generate a safety factor for the tree, and how various pruning methods could alter this. Whilst this inspection was being undertaken, we carried out an aerial assessment of any identified features using a drone and high-definition camera. This allowed access into the canopy without risk to a climber or the tree through rope damage, etc. Ultimately, the use of the drone also allowed us to capture aerial images of the tree in its setting, and this was combined with the use of photogrammetry capture to render the tree in a 3D visualisation that is hosted online.
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The Outcome
TMA had already carried out a tree survey for the College; however, the enhanced level of data collection and reporting further demonstrated that the tree is retainable long-term with no works required at this stage. The 3D imagery is able to be accessed wherever the viewer is, allowing people to experience the tree worldwide. This method has opened the door for ‘tree sponsorship’ as a viable method of commemoration, rather than donating trees or furniture that might cause unforeseen issues to gardens.
