Aspen site index as related to plant indicators

Eighty-five fully stocked, even-aged, aspen stands representing a wide range of ages were examined. Using published site index equations, the site index of these stands was estimated. A second available indicator of the site quality was the soil productivity group used by the Soil Survey. Each of these site quality indicators was related to synecological coordinates (moisture, nutrient, heat, light) of 85 stands. In this case, synecological coordinates were identified through the use of indicator plant species (synecological coordinates)