This study evaluated the effects of improved tropical grass and grass–legume pastures on the physical condition of an oxisol, previously covered by native savanna. Two long-term pasture experiments with different grass and legume species and with different stocking rates were used. Measurements were made of bulk density, penetrometer resistance, water retention characteristics, total porosity, pore-size distribution and water infiltration rate. The bulk density of the 0–5 cm and 6–11 cm layers was not affected by any of the treatments