Tree Risk Assessment & Decay Detection – Purple Beech – Sheffield
Location: Sheffield
Service: Tree Risk Assessment, Sonic Tomograph & Resistograph Testing
Tree Type: Overmature Purple Beech
Objective: Assess structural integrity due to visible wound and deadwood
Project Overview
JCA was initially commissioned to carry out a BS5837 development tree survey at a proposed site in Sheffield. During this survey, one prominent tree—a large overmature Purple Beech—was flagged for further investigation due to a significant stem wound and the presence of moderate deadwood.
Without the defect, this tree would have likely been classified as Category A, due to its landscape and arboricultural value.
Reason for Further Testing
The development survey identified:
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A large wound on the eastern side of the stem and canopy
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Overhanging branches close to an existing unit and car park
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Potential targets in the event of limb or stem failure
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The possibility of a lightning strike, later determined to be the likely cause (initially believed to be branch tear-out)
Due to the location and potential risk to people and property, advanced decay detection methods were recommended.
Decay Detection Methods Used
To accurately assess the internal structure of the tree, JCA carried out:
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Sonic Tomography (Sonic Decay Detection)
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Resistograph Testing
Key Findings
✅ Sonic Tomograph Results:
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The tree was structurally sound overall
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Only two minor areas of decay were detected
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The decay was not located near the visible wound
✅ Resistograph Results:
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The wood showed good structural integrity
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No evidence that decay had spread radially from the wound
Outcome & Recommendations
Despite some minor decay, the Purple Beech was found to be structurally stable at the time of inspection. As a result:
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No immediate remedial action was required
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The tree was retained in place
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Annual re-inspections were recommended to monitor its condition and ensure continued safety, especially due to its location overhanging high-traffic areas