New Edition
This manual is a valuable resource for both the expert and novice risk assessor. As the companion publication for the Tree Risk Assessment Qualification (TRAQ) program, this manual provides a systematic and structured approach to tree risk assessment, including levels of assessment, target and site assessment, tree biology and mechanics, tree inspection, mitigation, and reporting. The combined subjects of this manual guide assessors in estimating the likelihood of a tree or tree part failing as well as the amount of damage that would result from failure.
Key additions and revisions in this edition include:
- The text and terminology have been updated to be consistent with ISA’s BMP—Tree Risk Assessment, Third Edition (2025).
- Terminology is defined to reflect current industry practices and to be consistent with other disciplines, such as meteorology and engineering.
- Modules 1, 3, 4, and 5.3 were reorganized to improve flow and comprehension.
- The type of work to be performed in a tree risk assessment, a tree inspection, and a worksite inspection has been described.
- New guidance for assessing the likelihood of impact has been provided.
- Advanced assessment techniques descriptions have been expanded. Use of advanced techniques (e.g., drilling, tomography) to quantify the extent of decay, how decay reduces load bearing, and limitations of formulas to estimate loss of load-bearing capacity have been expanded.
- Several case studies have been rewritten or added, including an example of a written tree risk assessment report.
- More drawings, photos, and diagrams have been added to illustrate key concepts.
- In each module, key information has been summarized in sidebars.
- The roles of the tree risk manager and the tree risk assessor have been clarified.
- Additional guidance for calibrating assessments and ratings has been added.
- Consideration for wildlife habitat has been expanded throughout the text.
- The ISA “Basic Tree Risk Assessment Form” has been revised to enhance ease of use and to reflect changes in terminology.
(©2025, softcover, 238 pp., full-color illustrations and photos, glossary, index)
Also available as part of the TRAQ 3.0 Bundle which consists of the Tree Risk Assessment Manual, Third Edition (2025) and the Tree Risk Assessment Clipboard.
Download Basic Tree Risk Assessment Form.
**If you plan to take the Tree Risk Assessment Qualification program, please be advised that a downloadable digital copy of the Tree Risk Assessment Manual will be provided as part of the registration, with the option to acquire a print copy at a discounted rate. No discounts or refunds are provided for ISA TRAQ program registration for those who have previously purchased the Manual. For more information click here.