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We studied 11 soil profiles representing four physiographic groups. The dominant clay mineral in the total and fine clay of all the pedons was kaolinite, which was less ordered in the fine clay.

Describes the Arizona ghost town of Swansea, in the Buckskin Mountains, which was once a gold and copper mining town. Landscape and ruins; Prospecting, growth and death of town; Travel information.

Total loess (predominantly Peorian loess) thickness in southeastern Illinois and southwestern Indiana ranged from somewhat less than 40 inches to more than 300 inches, and the thinning rate of the loess was a linear function of the logarithm of the distance from the source. Peorian loess was present throughout the area, but Farmdale loess was present in significant amounts only in extreme southern Illinois and in extreme southwestern Indiana. Loveland loess was present sporadically beyond the limit of Illinoian glaciation. In the Wabash basin, loess thickens to the south as the valley becomes wider, the loess‐receiving landscapes become older, and the sediments in the valley become more silty. West‐northwest winds were important in the loess deposition of this region, but deposition of loess by easterly and southwesterly winds in the lower Wabash and Ohio river basins was shown to be more important than has been previously noted.

Surfaces of peds from B horizons of several Illinois soils were studied. Concepts of “structural specific surface” and of “disparity” between the ped surface and ped interior are presented. The ped surfaces are described in terms of accretive (accumulation) and degradational (removal) alteration classes. Aspects of the moisture regime at the ped surface are discussed. Ped surfaces were sampled by washing kerosene‐saturated peds with Calgon solution. Clay in the ped surface generally has more fine clay (<0.04µ) and more coarse clay (>0.5µ) than clay from bulked (whole) peds. Collapse from 14Å to 10Å is less complete on heating to 450°C. for the clay from the ped surface. In samples of peds with significant percentages of both montmorillonite and nonexpanding 2:1 lattice clays, the predominantly accretive ped surfaces have more mortmorillonite than the bulked peds, whereas predominantly degradational ped surfaces have less.

Two Gray‐Brown Podzolic soils and two Gray‐Brown Podzolic to Brunizem intergrade (transition) soils which occur near the forest‐prairie border in east‐central Illinois were studied to determine the effect of vegetation upon soil properties. All four profiles developed in loess and calcareous till of similar age and in the same climatic area so that soil differences are related to length of occupancy by trees, forest composition, and natural drainage. The Gray‐Brown Podzolic soils are more highly weathered and show more forest influence than the transition soils. This is indicated by higher organic carbon content and base status in the Al horizons; higher clay maxima, higher cation‐exchange capacities, lower Ca/Mg ratios, and lower base status in the B2 horizons; and less organic matter in the lower horizons of the Gray‐Brown Podzolic soils than in the transition soils. The relationships between soil properties and the vegetation sequence in north‐central United States are reviewed.

Results are presented from laboratory investigations of Beta horizons (clay‐enriched layers found below the B2horizons) of selected soils in the Wisconsin‐age glaciated region of northern Illinois. Stereoscopic microscopic investigations indicated the peds were microconstructional. This was interpreted to be the result of not only the arrangement of skeletal material in situ, but also the effect of colloidal material which has moved into the horizon from above and deposited on surfaces of grains, peds, and walls of pores to alter the microconfiguration and porosity. Microscopic studies of thin sections showed a rather porous fabric with a large percentage of the clay being strongly oriented in layers along surfaces of mineral grains, walls of pores and root channels, and surfaces of peds. Thin sections of sand columns through which clay suspensions had been passed had a fabric markedly similar to that of Beta horizons. These micromorphological investigations strongly suggest that the Beta horizon is primarily a zone of clay illuviation. Mechanical analyses indicated that the total clay fraction (< 0.002 mm.) was at a maximum in the B2horizon and that fine clay was at a maximum in the Beta horizon of each profile. Amounts of organic matter by weight were about the same in the B2and Beta horizons. On the other hand, if amounts of clay and organic matter were expressed on a specific surface area basis, the Beta horizon was appreciably higher than the B2horizon of the same profile. Clay mineral analyses indicated that the Beta horizons are characterized by a montmorillonitic suite more closely associated with the loess‐influenced material in the upper part of the soil than an illitic clay suite which characterizes the drift material below. The reaction ranged from pH 6.0 to 7.7 for most of the Beta horizons with the lower portion of the horizon having the highest pH. Clay migration was suggested as the dominant process in the development of the Beta horizon and it was closely related to the discontinuity in moisture flow at the boundary of the coarser textured substrata and finer textured subsoil.

Multiple correlations were determined between liquid limit, plastic limit, and plasticity index and various combinations of standard physical and chemical determinations (cation‐exchange capacity, percent of organic carbon, percent of <0.002‐mm. clay, percent of montmorillonite in the clay separate, percent of illite in the clay separate, and percent of 0.05‐ to 0.002‐mm. silt) on a wide range of Illinois soils. Multiple correlation coefficients of 0.959, 0.887, and 0.938 were obtained between liquid limit, plastic limit, and plasticity index, respectively, and three soil properties (percent of organic carbon, percent of clay, and percent of montmorillonite in the clay separaate), indicating that there is a very close relationship between Atterberg limits and these three soil properties. If additional soil properties, such as percent of silt and percent of illite in the clay separate, are included in the analysis the correlation coefficients are increased only slightly. Lower, but highly significant correlations were also obtained between each of the Atterberg limits and cation‐exchange capacity, and a combination of percent of organic carbon and percent of clay.

Precipitation and maximum daily temperatures 50 to 74 days before and 14 to 30 days after full tassel explained up to 67% of the corn yield variability during the period 1903 through 1956. When the upward trend in yields was included in this analysis, approximately 75% of the corn yield variability was explained.