Hydrological scores for grades of pedality based on correlations with measured steady infiltration rates for a wide range of soils, as determined by Lin et al. (1999): single grain (50), massive (0), weak (1), moderate (5), or strong (25). In this classification, single grain is listed as a very strong class under ped grade to compare sand with other textural soils. Pedality derives from McKenzie et al. (2000).