Dynamic Analysis of the Annual Growth of Paulownia Clones in Seedling Stage

The properties of annual growth of Paulownia clones were simulated by Logistic curve, and the maximum points of growth rate per day and durations of fast-growing stage were estimated. The clonal growth curves were approached by cross cut polynomiad and the coefficients β0、β1 and β2 which made up the growth curves were tested. The results show that the differences of growth curves are significant. The annual growth process of Paulownia clones was classed into early, intermediate and later three periods.