Effect of tree roots on shallow-seated landslides

Abstract

Forest vegetation, especially tree roots, helps stabilize hillslopes by reinforcing soil shear strength. To evaluate the effect of tree roots on slope stability, information about the amount of roots and their strength should be known. A simulation model for the root distribution of Cryptomeria japonica was proposed where the number of roots in each 0.5-cm diameter class can be calculated at arbitrary depths. The pull-out strength of roots was used to analyze the stability of four different types of forested slopes. Root reinforcement is important on slopes where roots can extend into joints and fractures in bedrock or into a weathered transitional layer between the soil and bedrock. Root reinforcement of soil increases quickly after afforestation for about the first 20 years, then remains about constant thereafter.

Parent Publication

• Proceedings of the IUFRO technical session on geomorphic hazards in managed forests: 5-11 August 1990: Montreal, Canada

Citation

Abe, Kazutoki Abe; Ziemer, Robert R. 1991. Effect of tree roots on shallow-seated landslides. Rice. Raymond M., technical coordinator. 1991. Proceedings of the IUFRO technical session on geomorphic hazards in managed forests; 5-11 August 1990; Montreal, Canada. Gen. Tech. Rep. PSW-GTR-130, Berkeley, CA: Pacific Southwest Research Station, Forest Service, U.S. Department of Agriculture; p. 11-20