Establishment of poplar (Populus spp.) plantations for meeting the demand of wood and bioenergy production necessitates reclamation of agricultural lands such as those in the Columbia Plateau of Oregon. The effects of management on soil C storage and nutrient concentrations were evaluated, using a chronosequence of poplar stands on soils of eolian origin (Xeric Torripsamments). Stands of ages 1, 3, 4, 7, 9, and 10 years, as well as adjacent agricultural and desert lands, were compared based on soil C, inorganic C (SIC), total N, and nutrient concentrations within the 0- to 50-cm soil depth. The 7- through 10-year-old stands that were in a first-rotation cycle were irrigated and fertilized. The 1- through 4-year-old stands in a second-rotation cycle received a mulch application treatment in addition to the irrigation and fertilization treatments. At age 11 years, the projected plantation C (147.5 Mg ha^-1) accumulated almost entirely in the aboveground biomass (62.2 %), forest floor (24.3 %), and roots (11.7 %). There were no significant increases in soil C and N contents with stand age, despite the presence of increasing trends within the surface layer. The accumulation in soil C content (~ 1.8 %), from the first- (23.5 ± 1.7 Mg C ha^-1) to the second-rotation stands (26.3 ± 3.5 Mg C ha^-1), was partially offset by a loss of SIC due to irrigation. The SIC content had a decreasing trend, which was related to dissolution of calcite along the soil profile, from the first- (16.7 ± 3.4 Mg C ha^-1) to the second-rotation stands (8.4 ± 5.0 Mg C ha^-1). Soil pH (r > 0.6) and exchangeable acidity (r = – 0.5) patterns were dependent upon the concentration of exchangeable Ca²⁺. In coarse-textured soils, a decadal time scale was insufficient to measure significant changes in soil C content.