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Soil physical properties crucially affect vegetation restoration on the semi-arid Loess Plateau. Understanding how converting cropland into grassland affects soil physical properties is essential throughout a long-term natural vegetation restoration chronosequence. The objectives of this study were to determine the effects of naturally restored grassland from cropland (wheat) on soil physical properties over time. Hence, we analysed the effects on various soil physical properties at different restoration ages (0, 5, 15 and 30 years). Our results revealed that soil physical properties changed dynamically in response to the land use change over time. Grassland restoration increases soil texture coarseness in the upper soil layer (0-5 cm). After a 15-year restoration, soil hydraulic conductivity attained the maximum measured value, but in restoration age (to 30 years) did not further improve soil hydraulic conductivity. Restoration increased the field capacity and the soil water content under the restored grassland when compared with the cropland, but increases were not linearly related to the restoration age. Our study suggests that converting cropland into grassland improved the soil structure and soil-water conditions, and that the first 15 years of restoration was sufficient in order to achieve most of the improvements in soil physical properties. Our results will be helpful in providing soil hydraulic parameters to other researchers with the aim of improving the restored grassland to become more effective and sustainable on the semi-arid area. Copyright (C) 2016 John Wiley & Sons, Ltd.