In conducting an appraisal of trees on commercial property, the value of landscape trees is based on the cost of replacing them in the same location with a plant of the same (or comparable) species. The formula used is called the Replacement Cost Method. Another approach commonly used is referred to as the Trunk Formula Method. Values are obtained using the International Society of Arboriculture (ISA) Guide for Plant Appraisals in conjunction with the Western Chapter Species Classification & Group Assignment Guide. Appraisals are based on the following factors:
~ Size: A measurement of the diameter of the tree at breast hieght (DBH). 4-1/2' above grade level.
~ Species: This factor considers the tree's adaptability, suitability, and performance within our valley.
~ Condition: This factor reflects on the overall health and structural integrity of the individual tree.
~ Location: This factor evaluates the site in which the tree is growing, its contribution to the site, and its placement with regards to the surrounding environment.