Soil Survey of Crater Lake National Park, Oregon
General Soil Map Units
Soils That Are in Valleys and Formed in Ash and Pumice Flow Deposits of Ash, Pumice, and Cinders
Number of map units: 4
Percentage of park: 42 percent
5. Castlecrest-Umak (mountain hemlock with lodgepole pine)
Percentage of park: 25 percent
Location in park: Lowlands and valleys near the northern, western, and southern boundaries
Crater Lake National Park, Oregon 19
Depth class: Very deep
Elevation: 4,500 to 7,500 feet
Average annual precipitation: 50 to 70 inches
Average annual air temperature: 38 to 42 degrees F
Frost-free period: 0 to 50 days
Minor components: 5 percent Timbercrater soils, 5 percent Unionpeak soils, 5 percent Sunnotch soils, and 5 percent Llaorock soils
Present vegetation: Mountain hemlock and lodgepole pine
Castlecrest soils
Drainage class: Somewhat excessively drained
Permeability: Rapid
Position on landscape: Mountain flanks and mountainsides
Parent material: Ash and pumice
Surface and subsoil texture: Paragravelly ashy loamy sand
Substratum texture: Ashy coarse sand and ashy sand
Slope range: 0 to 80 percent
Umak soils
Drainage class: Excessively drained
Permeability: Very rapid
Position on landscape: Pumice flows
Parent material: Pumice and ash
Surface texture: Paragravelly ashy fine sandy loam
Subsoil texture: Extremely paracobbly ashy loamy sand
Slope range: 0 to 10 percent
