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Surface-applied biosolids can affect the physical properties of the topsoil and promote the rehabilitation of degraded soils. In this study, the effects of time after biosolids application (1-3, 6, 12, and 18 months) and biosolids application rate (0, 7, 18, 34, and 90 Mg ha[sup -1]) were assessed on selected physical soil properties, from shrubland (Ustic Calciargid) and grassland (Vertic Paleargid) soils. The bulk density (BD) of the 0- to 2.5-cm soil depth was significantly (P≤0.05) affected in the two soils and decreased approximately 10% in the 90 Mg ha[sup -1] treatment with respect to the 0 Mg ha[sup -1] treatment. Time-to-runoff (TR) in the grassland soil and infiltration rate (IR) in the shrubland soil were significantly affected (P≤0.05) by time after biosolids application, and both TR and IR were significantly increased (P≤0.05) by rate of biosolids application in the two soils. For the shrubland soil treated 18 months before rainfall application, TR and IR increased from 74 sec and 23.7 mm hr[sup -1] in the 0 Mg ha[sup -1] treatment to 446 sec and 104.2 mm hr[sup -1] in the 90 Mg ha[sup -1] treatment. Organic matter (OM) content in the 0- to 3-cm soil depth of the two soils significantly increased as rate of biosolids application increased. Clay dispersibility significantly (P≤0.05) decreased in the 0- to 3-cm soil depth of the soils treated with 90 Mg ha[sup -1] of biosolids as compared to untreated soils. However, neither rate, nor time after biosolids application affected the OM contents, the BD, or CD of the 3- to 8-cm soil depth in any of the two soils. Surface-applied biosolids have the potential to increase the TR and IR of degraded soils, but 18 months after application at rates as high as 90 Mg ha[sup -1], biosolids only affected the physical characteristics of the 0- to 3-cm soil depth. [ABSTRACT FROM AUTHOR] more...