通过对坡面崩塌地残存根系分布的调查和根系抗拉试验，得知直径d≤20mm与d≥20mm的根系在破坏时会产生不同的抵抗力，将底面、侧面、源头部的根系抵抗力合计起来则是崩塌地的全部抵抗力。根系抵抗力用简易亚恩布法进行固地解析，其结果在降雨时，即使粘着力C＝0，也不会发生崩塌，坡面安全系数FS1≥1，FS2≥1。然而在无树木的坡面上，当c≤0．197t／m2时，却易发生崩塌，FS3≤1。 Through the investigation of the residual root distribution and the root tension test, it is found that the roots with diameters d≤20mm and d≥20mm will produce different resistance when destroyed, and the root resistance of the bottom, side and head Taken together is the collapse of all the resistance. The root resistance is analyzed by simple Yanb method for soil analysis. As a result, it will not collapse even when the cohesion C = 0 during rainfall. The slope safety factor FS1≥1 and FS2≥1. However, on the treeless slope, when c≤0.197t / m2, it is easy to collapse, FS3≤1.