For use by qualified professionals in conjunction with the 10th Edition of the Guide for Plant Appraisal published by the International Society of Arboriculture. As of July 2019 the Appraisal Factors for Illinois have been updated. These factors will be updated by the Regional Plant Appraisal Committee every 4-5 years, or as needed.
Updated Illinois Appraisal Factors
The Plant Appraisal Committee has updated the Appraisal Factors for use in plant appraisals in Illinois. Below are links to the Illinois Regional Map and updated appraisal factors for each region in Illinois. In past surveys only a handful of species were surveyed. In the 2019 data collection a total of 60 deciduous and evergreen plants were surveyed and calculated based on the following criteria:
Region 1 Factors
Region 2 Factors
Region 3 Factors
Region 4 Factors
The Regional Map has also been redrawn in order to better reflect the areas where regional grower markets exist. Please use this map to determine which set of regional replacement tree data to consult while performing your appraisals.
The 10th Edition of the Guide has brought a few changes to the appraisal process. Below are a few them:
Plant Appraisal Committee Members:
Aaron Schulz, Chair