Churchill College i-Tree Eco Study
ARBORICULTURE
Client
Cambridge University Botanic Gardens
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Project Type
Park, Education
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Location
Cambridge
TMA Environmental Consultants (TMA) was commissioned by Churchill College, University of Cambridge, to undertake a comprehensive tree inventory and risk assessment across the college estate. In addition to assessing tree condition and safety, the project sought to better understand the environmental benefits provided by the site’s extensive tree population. By combining arboricultural survey data with ecosystem service analysis, TMA helped the college quantify the value of its urban forest and support its wider environmental objectives.
Overview
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The Cambridge University Botanic Garden (CUBG) is a 16-hectare living museum and research site within central Cambridge. TMA have been appointed as consultants for arboricultural risk management for over 10 years, and have supported the gardens manage their tree collection balancing the need to retain trees within the gardens for educational, environmental and cultural purposes, against the risk of harm to the thousands of daily visitors.
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Challenge
The gardens receive around 350,000 visitors per year, making the paths and benches within the gardens relatively high occupancy. During the winter, when occupancy might be expected to be lower, the gardens put on a winter lights show, resulting in high visitor numbers year-round. The trees at CUBG have varied lineages and origins – many species are rare having been collected from the wild internationally, or particular varieties such as the Cambridge oak, and are a mixture of ages and sizes smaller young planted species, to large spreading mature trees planted during the gardens original development in 1846.
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Approach
TMA carried out a full tree inventory survey, risk assessing trees as necessary, using an industry recognised target-driven risk assessment methodology. Works were recommended using a timescale priority in accordance with the client’s instruction. Each tree was risk categorised, to inform a recommended survey cycle, based on the tree size, target level and condition.
Outcome
Following several survey cycles, TMA continue to advise the gardens on tree risk management and general arboricultural practice, have carried out specialist investigations such as sonic tomography, resistance drilling and dynamic load testing and have provided training and information about tree risk management inspection to the garden apprentices, including demonstration advanced diagnostic techniques when such work is being carried out at the garden. TMA have also provided advice relating to research projects requiring use of the garden tree stock and suggesting methodologies to facilitate this.
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​Services Provided
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Risk & Condition survey
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Special investigations
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Ecology
