Brinkerton , Calvert , Croton , Ginat , Robertsville , Sheffield , and Thorndale soils are in the same family. Brinkerton, Sheffield and Thorndale soils have bedrock deeper than 5 feet. Calvert and Croton soils have sola of less than 40 inches thick. Ginat soils have mica and a few pebbles in the lower part of the series control section. Robertsville soils do not have an argillic horizon above the fragipans.
Doylestown soils are on nearly level and gently sloping upland flats and depressions.
Slopes range from 0 to 8 percent. These soils formed in silty materials, presumably eolian, deposited over a wide variety of material weathered from shale, sandstone, limestone, schist and gneiss. The climate is humid temperate, with mean annual precipitation of 38 to 48 inches, mean annual air temperatures of 50 to 55 degrees F., and a growing season of 170 to 200 days. Abbottstown , Chester , Duncannon , Glenelg , Lansdale , Lawrenceville , Penn , Readington , Steinsburg and the competing Croton soils and Chalfonte are on nearby uplands. Abbottstown, Lawrenceville and Readington soils do not have a dominant chroma of 2 or less immediately below the A horizon.