The Gompertz equation possesses a multiplicative reproductive property, that is, if X follows the Gompertz equation and a and b are oonstants, then aX^b follows the Gompertz equation. Utilizing this property, the height growth and the volume growth of one tree can be estimated by the diameter growth of tbe same tree.
The Gompertz equation was divided into three types according to the number of free parameters in equations, thatis, the 3-parameter Gompertz, the 2-parameter Gompertz, and the 1-parameter Gompertz equations. The application of these three types of the Gompertz equation to 52 observed diameter, height and volume growths showed that the Gompertz equation fitted the observed data sufficiently, and that it was possible and practicable to predict the height growth and the volume growth by the parameter estimates for the diameter growth.