In this study, the guide position exponential curve second derivative Age Age 0 as a reference, calculated by reference Metasequoia age 20a (A0 = 20a), a reference age poplar 8a (A0 = 8a)
In this study, the age of the second derivative of the status index-oriented curve was 0 as the base age, the base age of the water fir was calculated to be 20a (A0-20a), and the base age of the poplar tree was 8a (A0-8a)
In this study, the age when the second derivative of the site index guidance curve is 0 is selected as the reference age. Through calculation, the reference age of Metasequoia is 20A (A0 = 20a), and that of poplar is 8A (A0 = 8a)<br>