Client Overview

Cork City Council’s Parks & Recreation Department plays a vital role in managing Cork’s urban trees, parks, and green spaces. Their dedicated team works year-round to protect mature trees that contribute to the city’s character and biodiversity, while also ensuring public safety and responsible risk management.

Urban trees bring huge value, providing shade, improving air quality, and supporting local wildlife but they also need careful monitoring as they age, especially when signs of decay or fungal infection appear. Visible cavities and fungal fruiting bodies can be indicators of internal decay that may compromise a tree’s structural stability. If decay is present, how advanced is it?. Is the tree posing an unacceptable risk to the public or property? Does the tree need remedial work or worse full removal?. Removing a mature urban tree unnecessarily is a loss for the community, the local landscape and for the many other species that rely of urban trees for habitat.

Recognising this, the City Tree Officer, requested a detailed investigation that would go beyond a standard visual check. Using sonic tomography technology, we could get an accurate, non-invasive view of what was happening internally without causing further harm.

Challenges & Solutions

The subject tree, a mature lime, had a notable cavity on the western side of the main stem. Pronounced reaction wood and hollow-sounding areas indicated potential structural weaknesses. Its location along a busy public road meant that the risk of harm resulting from a structural failure is high.

To address these issues, we:

• Carried out a detailed visual inspection to identify external defects and signs of decay.

• Used the Fakopp Arborsonic 3D Tomograph to perform non-invasive internal decay detection at three heights, 30 cm, 60 cm, and 90 cm above ground.

• Positioned 24 sensors at each level to generate high-resolution sonic tomograms.

• Analysed the results, which confirmed extensive heartwood decay but a healthy, structurally sound sapwood layer maintaining the tree’s stability.

• Provided a clear report with calculated safety factors, showing that the tree remains within safe load-bearing limits for its size and location.

The findings supported retaining the tree with a proactive pruning plan and ongoing monitoring to ensure public safety.

Key Benefits of Using a Tomograph

• Provided a non-invasive, data-driven assessment of the tree’s internal structure, ensuring no harm to the living tissue.

• Identified a pocket of heartwood decay, giving the client clarity on the tree’s true condition.

• Confirmed the tree’s stability, avoiding unnecessary removal and enabling the tree’s retention.

• Offered clear, actionable recommendations.

• Reduced the client’s liability by demonstrating due diligence and risk assessment using advanced testing technology.

 

If you’d like to explore how sonic tomography could support your project, Holly Arboriculture is here to help. Our advanced tree decay detection services provide the data and insights you need to make informed, confident decisions about tree retention, safety, and long term plans.

For more information or to discuss a project, please contact us at info@hollyarb.ie.