They have a small amount, less than 20 percent, of volcanic ash in the surface layer. These soils are in a semiarid climate with cool, moist winters and warm, dry summers. The average annual precipitation is 9 to 12 inches. Average January temperature is 28 degrees F., average July temperature is 71 degrees F., and average annual temperature is 48 to 52 degrees F. Frost-free season is about 130 to 180 days. These are the Esquatzel , Gravden , Mikkalo , Ritzcal , and Willis soils.
Esquatzel soils are on bottomlands and have irregular distribution of organic matter.
Gravden soils are on terraces and are loamy-skeletal and have a duripan. Mikkalo soils are on uplands and are 20 to 40 inches deep to bedrock. Ritzcal soils are on uplands and are calcareous throughout. Willis soils are on terraces and have a lime-silica duripan at a depth of 20 to 40 inches. Native vegetation is bluebunch wheatgrass, Sandberg bluegrass, Wyoming big sagebrush, and yarrow.