Abstract:In order to understand the differences of fine root morphology and biomass allocation among different provenances of Phoebe zhennan, the fine root morphology and biomass of 2.5-year-old seedlings of 13 provenances in natural distribution areas were studied by root investigation method. The results showed that the average diameter, total root length and surface area of fine roots among P. zhennan provenances were different significantly, with root order increased the average diameter of fine roots enlarged within provenances, but the difference of total root length and surface area between root orders was not obvious. Allocation of biomass enhanced as root order increased, which from 1- to 4- grade-root accounting for 6.33%, 14.47%, 25.03% and 54.17%, respectively. Through comprehensive evaluation, the root system of HT, LF, ES and WC provenances were optimized with high growth potential.