Resumen
The monetary value of landscape trees is needed for various purposes including tree inventories, real estate transactions, lawsuits, insurance claims, tax purposes, and tree care investment decisions. Several formulas and methods have been developed to determine these values. The most widely used method, the trunk formula method, requires a species rating value for the tree being appraised. Pooling judgments and opinions of tree experts, such as foresters, horticulturists, landscape architects, nurserymen and arborists, is a widely used procedure to derive species rating value. Due to differences in training and background of tree professionals, and the wide variability of landscapes in any given area, professional agreement on the rating of a species is difficult to reach, but yet, necessary to be useful. This study describes our experiences in developing species rating values for Louisiana trees using the traditional technique of pooling expert opinions and the associated difficulties and problems others might encounter going through a similar undertaking in Florida. This study also examines the degree of agreement among the professional groups in the rating of species listed for Louisiana by the International Society Arboriculture (ISA).
