LOCATION DYAROCK OREstablished Series
TAXONOMIC CLASS: Ashy, amorphic Oxyaquic Vitricryands
TYPICAL PEDON: Dyarock very gravelly ashy loamy sand, rangeland. (Colors are for moist soil unless otherwise noted.)
A1--0 to 1 inch; very dark brown (10YR 2/2) very gravelly ashy loamy sand, grayish brown (10YR 5/2) dry; single grain; loose, nonsticky and nonplastic; few very fine and fine roots; many very fine interstitial pores; 25 percent andesite gravel, 5 percent andesite cobbles, 5 percent andesite stones and 15 percent pumice paragravel; moderately acid (pH 6.0); clear wavy boundary. (0 to 3 inches thick)
A2--1 to 7 inches; very dark brown (10YR 2/2) ashy sandy loam, brown (10YR 5/3) dry; weak very fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine roots; many very fine and common fine interstitial pores; 5 percent andesite gravel and 5 percent andesite cobbles; slightly acid (pH 6.2); clear wavy boundary. (1 to 7 inches thick)
AB--7 to 17 inches; very dark brown (10YR 2/2) ashy sandy loam, brown (10YR 5/3) dry; weak very fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; many very fine and common fine interstitial pores; 2 percent andesite gravel; slightly acid (pH 6.2); clear wavy boundary. (3 to 15 inches thick)
Bw--17 to 30 inches; very dark grayish brown (10YR 3/2) ashy loamy sand, grayish brown (10YR 5/2) dry; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine and fine interstitial pores; 2 percent andesite gravel; slightly acid (pH 6.2); clear wavy boundary. (0 to 15 inches thick)
C1--30 to 44 inches; dark brown (7.5YR 3/3) gravelly ashy loamy coarse sand, brown (7.5YR 5/2) dry; massive; slightly hard, very friable, nonsticky and nonplastic; many very fine and common fine interstitial pores; 15 percent andesite gravel; slightly acid (pH 6.2); clear wavy boundary. (5 to 20 inches thick)
C2--44 to 62 inches; dark grayish brown (10YR 4/2) ashy coarse sand, light brownish gray (10YR 6/2) dry; single grain; loose, nonsticky and nonplastic; many fine and medium interstitial pores; 3 percent andesite gravel and 7 percent pumice paragravel; slightly acid (pH 6.2).
TYPE LOCATION: Klamath County, Oregon; Crater Lake National Park, about 100 feet west of caldera rim and 800 feet north of Watchman lookout; Latitude 42 degrees, 56 minutes, 58.45 seconds North, Longitude 122 degrees, 10 minutes, 13.95 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, 0.4 to 1.5 acid oxalate extractable aluminum plus one-half iron, 40 to 70 percent phosphate retention, and 3 to 12 percent 15-bar air-dry moisture content and 4 to 13 percent 15-bar water content moist. Clay content 0 to 5 percent by field estimate. Pumice content is 0 to 15 percent. Based on observations during the summer months and during the spring snowmelt period, the upper meter of the soil is saturated in some part for 20 or more consecutive days.
A1 horizon:
Value-2 or 3 moist, 3 through 5 dry
Chroma-2 or 3 moist and dry
Texture-ashy loamy sand or ashy sandy loam
Rock fragment content-0 to 55 percent
Organic matter - 1 to 2 percent
A2 horizon
Value - 2 or 3 moist, 4 or 5 dry
Chroma - 2 or 3 moist and dry
Texture - ashy sandy loam or ashy loamy sand
Rock fragment content - 0 to 30 percent
Organic matter - less than 1 percent
Bw and AB horizon:
Hue-10YR or 7.5YR
Value-2 through 4 moist, 3 through 5 dry
Chroma-2 through 4 moist and dry
Texture-ashy loamy sand or ashy sandy loam
Rock fragment content-0 to 25 percent
Organic matter - less than 1 percent
C horizon:
Hue-10YR, 7.5YR or 5YR
Value-3 or 4 moist, 4 through 6 dry
Chroma-2 through 4 moist and dry
Texture-ashy loamy sand, ashy coarse sand or ashy loamy coarse sand
Rock fragments-0 to 25 percent
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: The Dyarock soils are in swales on ash flows in mountain at elevations of 6,000 to 7,500 feet. The soils formed in ash mixed with rock fragments of pumice, cinders and andesite. Slopes are 2 to 20 percent. The climate is characterized by cold wet winters and cool dry summers. The average annual precipitation is 60 to 80 inches, mainly as snow. The average annual temperature is 38 to 42 degrees F. The frost-free period is 0 to 30 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cleetwood and Llaorock soils. Cleetwood soils are excessively drained. Llaorock soils are medial-skeletal and somewhat excessively drained.
DRAINAGE AND PERMEABILITY: Moderately well drained; rapid permeability.
USE AND VEGETATION: These soils are used for wildlife and recreation. Vegetation consists mainly of Brewers sedge, bottlebrush squirreltail, Parry's rush and western needlegrass.
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 0 to 30 inches
Ochric epipedon - although the color quality as mollic, the epipedon lacks the organic matter and/or thickness requirement for a mollic or umbric epipedon. The dark colors are lithochromatic.
Oxyaquic features - Redoximorphic features do not exist because of cold temperatures
Volcanic ash is from Mt. Mazama.
Particle-size control section - 0 to 40
Soil temperature regime - Cryic
Moisture regime - Udic