Variation of soil properties within mapping units of Seward, Rimer, Wauseon, Rawson, Haskins, and Mermill soils in northwestern Ohio was statistically summarized. These series have sandy or loamy upper sola that overlie a fine‐textured substrata. Ten randomly selected profiles within each of 22 delineations of these soils were characterized by field study. Standard deviation, standard error of the mean, and coefficient of variation were computed for each of 48 selected properties. The most variable properties were depth to mottling, depth to fine‐textured discontinuity, horizon thickness, texture, and chroma of the B2t horizon, percent of mottles having chromas of two or less, and grade of structure. Hue, value, and pH of all horizons, texture of the IIB horizon, and size and shape of structure were the least variable. 54% of the profiles had IIB horizons in areas mapped as soils in which this horizon was lacking; 78% had IIB horizons in areas mapped as soils having this horizon. Little difference in other properties was noted between areas mapped as soils representing the two conditions. These soils were correctly classified with regard to soil series at 37% of the 220 observations. Careful study in such complex areas is essential before establishing a legend.