Slope gradients are 0 to 1 percent in the western part of the series range, and range from 0 to 11 percent in the eastern part of the series range. Slopes are typically convex. The mean annual temperature ranges from 50 to 55 degrees F, and the mean annual precipitation ranges from 22 to 34 inches. These are the Butler , Fillmore , Hall , Hastings , Holdrege , and Wymore soils. Butler soils are on flat or slightly concave uplands and have an abrupt boundary between the A and B horizon.
Fillmore soils have an albic horizon, are somewhat poorly drained and are in depressions.
Hall soils are fine-silty and are on nearly level to gently sloping terraces and uplands. Hastings, Holdrege, and Wymore soils are on nearly level to strongly sloping uplands. Holdrege soils have mollic epipedons less than 20 inches thick and have less clay in the argillic horizon. These soils have a slowly pervious layer within the upper 1 meter that keeps the soil wet close enough to the surface for long enough periods that planting or harvesting operations of field crops are adversely affected on some areas during prolonged wet periods. Nearly all dryland areas are cropped to sorghum and wheat.