Arid soils can be highly susceptible to erosion following disturbances and, due to the lack of moisture and vegetation, do not tend to “heal” readily.  The Desert Research Institute in Las Vegas, Nevada has a highly instrumented lysimeter facility operational for the last five years.  A comparison of the surface properties of the lysimeter soils with the soil surface properties of undisturbed soil from the nearby borrow site from which the lysimeter soils were obtained, provided the opportunity to assess the effect of disturbance.  Surface cover and crust development were characterized on both sites, hydraulic conductivity was measured using tension infiltrometers, and air permeability was measured using an air permeameter. There were marked differences between surface soil properties between sites due to structural development within the upper few millimeters of the soil.  Because the same surface soil was present at both sites, these differences between sites highlighted the role structure has in water and air flow in soils and the time scale of surface soil structural development in arid areas.