Erosion becomes a problem when human activity causes it to occur much faster than under natural conditions.
When properly installed and maintained, vegetation can protect slopes by reducing erosion, strengthening soil, and inhibiting landslides.
Too often, well intended erosion control and slope stabilization programs do not recognize and incorporate vegetation as a legitimate design tool to address these slope processes. Primarily, these oversights are due to the use of vegetation alone (soil bioengineering) or together with other slope stability structures (biotechnical engineering, hydroseeding etc.) for slope protection is poorly understood.
Therefore, the value of vegetation along a slope is either underestimated or ignored during the important project planning, design, and agency permitting periods.