Speelyai soils are on terraces and terrace escarpments at elevations of 400 to 600 feet. Slopes are 0 to 60 percent. The average annual soil temperature ranges from 49 to 53 degrees F. Depth to weakly cemented lahar ranges from 10 to 20 inches. The soil is 10 to 25 percent volcanic ash and 15 to 35 percent rock fragments in the particle-size control section.
Soil reaction ranges from neutral to very strongly acid throughout.
They are 15 to 35 percent pebbles and 5 to 25 percent volcanic ash. This is the Pacifico series. Pacifico soils are 5 to 15 percent granitic rock fragments and lack volcanic ash in the particle-size control section. Speelyai soils occupy dissected lahar terraces at elevations of 400 to 600 feet. They formed in aerially deposited volcanic ash and lahar of sand, gravel, and volcanic ash overlying weakly cemented very gravelly lahar.