LOCATION SUNNOTCH OREstablished Series
TAXONOMIC CLASS: Ashy-skeletal, amorphic Typic Vitricryands
TYPICAL PEDON: Sunnotch gravelly ashy sandy loam, on a 7 percent slope, forest. (Colors are for moist soil unless otherwise noted.)
Oi--0 to 1 inch; slightly decomposed needle litter, abrupt smooth boundary. (1 to 3 inches thick)
A1--1 to 3 inches; very dark brown(10YR 2/2) gravelly ashy sandy loam, very dark grayish brown (10YR 3/2) dry; weak fine and medium granular structure; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine interstitial pores; 10 percent black cinder gravel, 10 percent andesite gravel and 10 percent pumice paragravel; moderately acid (pH 5.9); abrupt smooth boundary. (1 to 5 inches thick)
A2--3 to 11 inches; very dark grayish brown (10YR 3/2) ashy loamy sand, brown (10YR 5/3) dry; weak fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine, fine, medium and few coarse roots; many very fine interstitial pores; 5 percent black cinder gravel, 5 percent andesite gravel and 5 percent pumice paragravel; slightly acid (pH 6.3); clear wavy boundary. (4 to 10 inches thick)
Bw--11 to 25 inches; dark brown (10YR 3/3) very gravelly ashy loamy sand, brown (10YR 5/3) dry; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine, fine and common medium roots; many very fine interstitial pores; 20 percent black cinder gravel, 10 percent red cinder gravel, 10 percent andesite gravel and 10 percent pumice paragravel; slightly acid (pH 6.4); clear smooth boundary. (9 to 25 inches thick)
2C--25 to 61 inches; dark brown (7.5YR 3/4) very gravelly ashy sand, brown (7.5YR 5/4) dry; single grain; soft, very friable, nonsticky and nonplastic; few fine roots; many very fine interstitial pores; 20 percent black cinder gravel, 10 percent black cinder cobbles, 15 percent andesite gravel, 15 percent pumice paragravel and 3 percent pumice paracobbles; slightly acid (pH 6.4)
TYPE LOCATION: Klamath County, Oregon; Crater Lake National Park, about one mile north of Red Cone spring and about 350 feet west of Boundary Springs trail, Latitude 43 degrees, 01 minutes, 0.37 seconds North, Longitude 122 degrees, 11 minutes, 29.83 seconds West; NAD 83. (GPS)
RANGE IN CHARACTERISTICS: Depth to bedrock is greater than 60 inches. The solum is 14 to 30 inches thick. The average annual soil temperature ranges from 39 to 43 degrees F. The soils are usually moist but are dry in all parts of the moisture control section for 30 to 45 consecutive days following the summer solstice. The solum has andic soil properties with 60 to 90 percent volcanic glass, 1.0 to 2.5 acid oxalate extractable aluminum plus one-half iron, 50 to 85 percent phosphate retention, 3 to 12 percent 15-bar air-dry moisture content and 4 to 13 percent moist 15-bar water content. The weighted average of 8xSi+2xFe is 5 to 8. The particle-size control section averages 35 to 50 percent rock fragments and 5 to 20 percent pararock fragments. Field estimated clay content is 0 to 5 percent.
A horizon:
Hue-10YR or 7.5YR
Value-2 through 5 moist, 4 through 6 dry
Chroma-2 through 4 moist and dry
Cinder gravel content-5 to 20 percent
Andesite gravel content-5 to 25 percent
Pumice paragravel content-0 to 20 percent
Bw horizon:
Hue-10YR or 7.5YR
Value-3 or 4 moist, 4 through 6 dry
Chroma-2 through 6 moist and dry
Texture-ashy sandy loam, ashy loamy sand, ashy loamy coarse sand, ashy coarse sand or ashy sand
Cinder gravel content-15 to 35 percent
Andesite gravel content-5 to 20 percent
Pumice paragravel content-0 to 10 percent
2C horizon:
Hue-10YR, 7.5YR or 5YR
Value-3 or 4 moist, 5 or 6 dry
Chroma-3 through 6 moist and dry
Texture-ashy loamy sand, ashy loamy coarse sand, ashy coarse sand or ashy sand
Cinder gravel content-15 to 40 percent
Cinder cobble content-0 to 15 percent
Cinder fragments larger than 10 inches-0 to 15 percent
Andesite gravel content-15 to 60 percent
Pumice paragravel content-0 to 15 percent
Pumice paracobble content-0 to 5 percent
COMPETING SERIES: These are the Currier, Domerir, Douthit, Esmeralda, Howson, Jimek, Lemah, and Nomalas series. Currier soils have 5 to 12 percent clay, have fine earth textures of loam or sandy loam, and have a solum thickness of 30 to 45 inches. Domerir soils are deep to bedrock and have channer shape rock fragments. Douthit soils have glacial till at 10 to 20 inches and have 5 to 15 percent clay. Esmeralda soils have a spodic horizon, have fine-earth textures of sandy loam or loam, and 15-bar water on dry samples is 12 to 15 percent. Howson and Jimek soils are moderately deep to bedrock. Lemah soils have a mean annual soil temperature of 44 to 46 degrees F. Nomalas soils have less than 30 percent glass and less than 0.4 percent acid oxalate aluminum plus half the iron below a depth of 30 inches.
GEOGRAPHIC SETTING: The Sunnotch soils are on volcanic debris flows at elevations of 5,000 to 8,000 feet. The soils formed in volcanic ash and cinders. Slopes are 0 to 45 percent. The climate is characterized by cold wet winters and cool dry summers. The average annual precipitation is 40 to 70 inches, mainly as snow. The average annual temperature is 38 to 42 degrees F. The frost-free period is 0 to 50 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Castlecrest and Llaorock soils. Castlecrest soils are ashy and found on the contiguous ash flows. Llaorock soils are medial-skeletal.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; rapid permeability.
USE AND VEGETATION: These soils are used for wildlife and recreation. Vegetation consists mainly of mountain hemlock, Shasta red fir, lodgepole pine with a sparse understory of balsam wood rush and forbs.
DISTRIBUTION AND EXTENT: Cascade mountains of central Oregon; MLRA 3. This series is of limited extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Crater Lake National Park, Klamath County, Oregon, 2001.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Andic properties - from 1 to 25 inches, based on laboratory data from associated Timbercrater, Umak and Llaorock soils.
The particle-size control section has a weighted average of 35 percent rock fragments.
Ochric epipedon - pedon has mollic colors to a depth of 25 inches but organic matter content is less than 1 percent below about 7 inches.
All depths to diagnostic horizons or other features are measured from the top of the first mineral horizon.