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Introduction The International Society of Arboriculture (ISA) developed a specialized Tree Risk Assessment Qualification (TRAQ), training arborists to effectively assess tree risk using a systematic and documented process. TRAQ arborists are equipped to systematically assess tree health, structural integrity, likelihood of tree failure, time frame in which failure may occur, likelihood of impact to target (e.g., people, home, car), and severity of impact should it occur. TRAQ arborists are trained to consider solutions to mitigate tree risk prior to considering removal as a recommendation. Tree risk management begins with the tree owner establishing an acceptable level of risk (ISA 2017) and identifying the appropriate level of assessment to determine the risk of individual trees. Three levels of risk assessment exist in the ISA TRAQ program which vary in detail and equipment used to complete the assessment: level 1 limited visual assessment, level 2 basic assessment, and level 3 advanced assessment (shown in the table below). Municipalities often utilize all levels of assessment throughout the City to balance risk assessment programs with responsible use of public funds. A level 1 assessment is often used to first identify trees that are high risk. Once high-risk trees or areas of concern are identified, a level 2 assessment occurs for individual trees and mitigation follows, A level 3 assessment is typically reserved for trees of significance, protected trees, or large mature trees that provide value to the community with costly replacement. Effective risk management depends on tree risk assessments being conducted on a regular basis, occurring every 3-5 years as tree risk conditions may develop as trees continue to mature. By utilizing these three assessment levels, the City can manage tree risk prior to failure and retain trees where risk can be mitigated. ISA Risk Assessment Levels Risk Assessment Level Description Level 1 ‘Windshield’ survey to identify high risk trees while driving or walking. Only major defects or concerns are observed and recorded. Level 2 360-degree observation of the crown, limbs, and trunk. Determination of targets (homes, people, cars) that may be impacted by tree or limb failure. Level of damage to the target should impact occur. Level 3 Advanced assessments of the roots, stem, or crown. Analyze internal aspects of trees using sophisticated tools and technology.