The Effect of Moisture on the Color of Certain Iowa Soils

The"official series descriptions, as given by the U^ S» Bureau of Soils, describe the color of each horizon. These must be interpreted by the field men and used as standards against ~which to check. In other words, the Carrington series is described as having dark brown surface soils and yellow to light brown subsoils* But will the soil surveyors conception of this "description coincide -with the authors or will different men interpret it alike. It is quite evident that the personal equation will enter too largely into the matter and that there is-grave danger of lack-of coordination,