Two finite element modelling approaches have been applied and compared to simulate direct shear tests of soils reinforced by roots. The "frictional behaviour" method used with solid elements predicted shear strength of the root-soil system 4.6-6.9% higher than that predicted with "embedded beam elements". This difference can be considered as negligible. Embedded beam elements were thus chosen to discretize digitized Maritime pine root systems in a tree anchorage model. Results exhibited contrasted mechanical responses when considering different root material properties.