Tree Appraisal


The Guide for Plant Appraisal, 10th Edition is the most informative and comprehensive alignment of current knowledge of the approaches, processes, and methods of plant valuation. This edition represents a systematic evolution of plant appraisal that integrates new research into a deeper understanding of the strengths and weaknesses of the available methods. Included in this edition are detailed discussions of newly streamlined core concepts and terminology, a review of the organization and context of appraisal reports, and an updated emphasis on appraiser awareness of the environmental and ecological benefits plants provide. Also new to this edition are appendices and a glossary. You can purchase this Guide here

Notice Regarding the Texas Supplement to the 10th Edition of the Guide for Plant Appraisal: The Texas Chapter ISA Regional Plant Appraisal Committee (RPAC) is working to implement significant technical changes between the 9th and 10th Editions of the Guide for Plant Appraisal.  Publication of a Texas Supplement to support the 10th Edition of the Guide is currently delayed pending additional clarification from CTLA.
In the meantime, the Texas RPAC has determined that 3” caliper (or #65 container), will remain the Largest Commonly Available size for calculating Unit Costs and other uses outlined in the 10th Edition of the Guide.
Under guidelines set forth in the 10th Edition, when utilizing the Trunk Formula Technique, it is now recommended that unit costs be calculated for each separate species of tree being appraised.  Tree costs are widely available from nursery catalogs and internet-based websites (such as, and tree appraisers are encouraged to utilize these or similar tree pricing sources when determining unit costs for a particular appraisal assignment.
If you have any questions or issues about the 10th Edition, please contact Micah Pace, Chair of the Texas RPAC, at

(For those who choose to continue using the 9th Edition, unit costs are provided in the 2019 Texas Supplement for the 9th Edition of the Guide available here. The 2019 update is the last update for the Texas Supplement for the 9th Edition of the Guide and it will no longer be updated annually by the Texas Chapter.)