Improved topsoil structural quality is expected under no‐till farming, but soil physical constraints can develop under continuous no‐till. Our objectives were: to evaluate the properties of loam, silty loam, and silty clay loam soils under various management practices on a regional scale; to clarify the relationship between soil organic matter pools and soil physical properties; and to find a minimum set of topsoil properties to characterize trends established by tillage. Thirty‐nine loam, silty loam, and silty clay loam soils were sampled from cropped fields managed using conventional tillage (CT) and no‐till (NT) as well as six undisturbed soils (uncropped). The A horizon thickness did not differ among soil textural groups and was 4 cm thicker in uncropped soils. Total and particulate organic C were significantly affected by management (uncropped > CT = NT, P < 0.001). Soil structural instability of uncropped soils (0.317 mm) differed from CT soils (0.723 mm) but not from NT soils (0.573 mm). Soil structural instability was negatively related to total and particulate organic C, and no relation was found with the resistant organic C pool. Water infiltration rate was the only topsoil property affected by a significant texture × management interaction. Lower infiltration rates in NT silty soils were caused by platy structural forms with horizontal pores. Soil penetration resistance (0–5 cm) was 0.77 MPa higher in NT than in CT soils. A minimum set of topsoil properties to evaluate tillage management includes structural instability, total or particulate organic C, infiltration rate, and penetration resistance.

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A regional study was conducted in the northern Pampas of Argentina in order to compare soil quality at proximal cropland sites that are managed under either continuous cropping (CC) (n = 11) or integrated crop–livestock (ICL) (n = 11) systems under zero tillage. In the ICL system, samples were taken in the middle of the agricultural period. Although soil total and resistant organic carbon (TOC, ROC) were significantly higher in silt loam soils than in loam/sandy loam soils, variations in carbon concentration were not associated with differences in soil management. Soil relative compaction was the only property that was significantly (P < 0.05) affected by the soil type × management interaction. Soil relative compaction values were significantly lower with ICL in loam/sandy loam soils, but there were no significant differences in silt loam soils. Structural instability index showed little change from CC to ICL sites, indicating that there was no soil structural damage. Soil penetration resistance was significantly higher in ICL soils within the first 0.075 m of soil depth, slightly exceeding the critical threshold (2000 kPa). However, firmer topsoil under ICL was not due to shallow compaction, as evidenced by no increase in soil bulk density.