Tree failure analysis involves the systematic evaluation of tree or limb failures to determine cause, contributing factors, and whether accepted arboricultural practices were followed. Failures may involve root plate instability, trunk defects, structural weaknesses, or environmental loading, and often require careful documentation and interpretation.

In many cases, the condition of the tree prior to failure, the presence of visible defects, and the actions taken by responsible parties are central to understanding what occurred. Proper analysis requires not only technical knowledge of tree biology and mechanics, but also practical experience with inspection methods, maintenance practices, and industry standards.

Tree failure analysis is commonly performed in matters involving property damage, personal injury, and disputes regarding tree care, risk management, and standard of care.

Common Causes of Tree Failure

Tree failures can result from a combination of structural defects, biological conditions, and environmental forces. Common contributing factors include:

• Advanced decay in the trunk or root system
• Root damage or restricted rooting conditions
• Poor structure, including codominant stems or included bark
• Soil instability or saturation
• Wind loading and storm-related forces
• Prior improper pruning or maintenance practices

In many cases, multiple factors are present, and determining the relative contribution of each condition is a key part of the analysis.

Tree Failure Analysis Methods

Evaluation of tree failure typically includes site inspection, documentation of remaining tree structure, and review of available evidence such as photographs, maintenance records, and witness accounts. Where applicable, examination of the failed components may provide additional insight into decay extent, structural integrity, and failure mode.

Analysis may involve assessment of visible defects, decay patterns, load distribution, and site conditions, as well as consideration of industry standards related to inspection, maintenance, and risk assessment. Findings are developed through a combination of field observations, technical knowledge, and experience with similar conditions.