Abstract:Based on the analysis of the correlation between diameter and height of forest trees, in consideration of topographical and geomorphic features on flat farmlands, site index table and quantified site index table of Paulownia plantations are worked out respectively, with average DBH as dependent variable of trees within the highest diameter diameter class replacing average height of dominant trees, and with stand average age and some qualitative factors as independent variables, such as soil type, thicknes of soil layers, underground water level, and tree spacing in the row. Further, Paulownia plantations are divided into 14 site types. The results are universal suitable to the method of related management tables, the dividing of site types and the pre-evaluation of stand growth for main tree species on flat farmlands.