There are few sites in the world where long-term effects of tillage on production systems can be evaluated. In NW Ohio (Hoytville), and NE OHIO (Wooster) no tillage (NT) and plow tillage (PT) have been continuously applied for 44 years to soils with contrasting characteristics: Wooster silt loam, well drained, and Hoytville silty clay loam, poorly drained. To investigate the effect of tillage on soil macro and micromorphology, porosity, and chemical soil properties, pits were excavated at both sites in NT and PT continuous corn plots and in adjoining grassed and wooded areas with less intensive land use. At both sites stronger structure and more bioturbation were evident in the topsoil of NT relative to that of the topsoil of PT, leading to lower bulk densities and increased macroporosities, fostering the expression of incipient E horizons in the NT soils. Liming influence is evident in Wooster between 0 and 57 cm under PT and between 0 and 77 cm under NT due to greater permeability as a result of greater pore continuity and basic cation retention related to greater C contents in the NT soils. The carbon pool (volumetric C content to a depth of 31 cm) is the same (6.72 and 6.75 kg m^-2, respectively) in the forest and NT soils in Wooster, and somewhat greater in the grass (7.45 kg m^-2) with lowest values (5.56 kg m^-2) occurring in PT. In the Hoytville soils, the forest and grass have the highest C pool values (11.85 and 9.35 kg m^-2, respectively) with slight differences between NT (7.04 kg m^-2) and PT (6.34 kg m^-2). These results suggest that there are constraints to the effectiveness of NT in sequestration of C in poorly drained soils; micromorphological observations reveal better stabilitization of organic matter decomposition products and increased structure amelioration with NT in Wooster.