In this dissertation, vertical distribution types of Robinia pseudoacacia and Pinus tabulaeformis were analyzed by field and laboratory experiments and theoretical analysis. Root tensile properties of five woody plants were tested by axial tensile tests. The relation of Pinus tabulaeformis root diameter and tensile property was studied. The effects of sampling time, species, root length and test speed on maximum tensile force and tensile strength of roots were also evaluated. And then effect of different la...