Flux boundary measurements for the study of tree stability.

The shear strength of soil is an important parameter that affects tree stability and can vary depending on the magnitude of the soil's negative pore-water pressure (matric suction). The surface flux boundary condition affects the matric suction of soil, and therefore is important for tree stability. Field measurements were performed around a roadside tree for 2 years. The instrumentation results show that the matric suction in the soil fluctuated between 0 and 35 kPa. Matric suction changes in the soil could lead to a decrease in the tree resistive moment of up to 80 %. [ABSTRACT FROM AUTHOR]