LOCATION GROUSEHILL OREstablished Series
TAXONOMIC CLASS: Medial-skeletal, amorphic Oxyaquic Duricryands
TYPICAL PEDON: Grousehill gravelly medial loam, woodland. (Colors are for moist soil unless otherwise noted.)
Oi--0 to 3 inches; slightly decomposed needle litter; clear wavy boundary. (1 to 4 inches thick)
A--3 to 10 inches; dark brown (7.5YR 3/3) gravelly medial loam, yellowish brown (10YR 5/4) dry; weak fine granular structure; soft, very friable, nonsticky and slightly plastic; many very fine, fine, medium and common coarse roots; many fine interstitial pores; 10 percent rounded andesite gravel, 5 percent rounded andesite cobbles and 5 percent pumice paragravel; slightly acid (pH 6.4); clear wavy boundary. (5 to 10 inches thick)
Bw1--10 to 31 inches; dark brown (7.5YR 3/4) very cobbly medial loam, brown (7.5YR 5/4) dry; weak very fine subangular blocky structure; soft, very friable, nonsticky and slightly plastic; many fine, medium and common coarse roots; many very fine interstitial pores; 10 percent andesite gravel, 30 percent rounded andesite cobbles, 15 percent rounded andesite stones and 15 percent pumice paragravel; slightly acid (pH 6.4); clear wavy boundary. (15 to 25 inches thick)
Bw2--31 to 39 inches; very dark grayish brown (10YR 3/2) very cobbly medial loam, yellowish brown (10YR 5/4) dry; weak very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common medium and few fine and coarse roots; many fine interstitial pores; 10 percent andesite gravel and 30 percent rounded andesite cobbles; slightly acid (pH 6.2); abrupt wavy boundary. (0 to 15 inches thick)
Bqm--39 to 56 inches; dark gray (10YR 4/1) moderately cemented duripan, light gray (10YR 7/1) dry; massive; extremely hard, slightly rigid.
TYPE LOCATION: Klamath County, Oregon; About 2.5 miles north of highway 62 and 1/4 mile east of park boundary; Latitude 42 degrees, 55 minutes, 53.52 seconds North; Longitude 122 degrees, 16 minutes, 41.48 seconds, NAD 83. (GPS)
RANGE IN CHARACTERISTICS: 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. Depth to a moderately cemented duripan is 20 to 40 inches. Clay content by field observation is 15 to 25 percent. The shape of the rock fragments are rounded to subrounded. The solum has estimated moist bulk density of 0.80 to 1.00 g/cc, phosphate retention of 85 to 95 percent and acid oxalate extractable aluminum plus one-half the iron of 2.0 to 5.0 percent. Based on observations during the spring snowmelt period the layers above the duripan are saturated for 20 or more consecutive days in April through June; (Oxyaquic). Andic soil properties are present throughout the soil material above the duripan.
A horizon:
Hue-10YR or 7.5YR
Value-2 through 4 moist, 4 through 6 dry
Chroma-2 through 4 moist and dry
Rock fragments-10 to 50 percent
Pumice paragravel-0 to 15 percent
Bw horizon:
Hue-10YR or 7.5YR
Value-3 or 4 moist, 4 through 6 dry
Chroma-3 through 4 moist and dry
Texture-medial loam or medial sandy loam
Rock fragments-35 to 70 percent
Pumice paragravel-0 to 20 percent
Bqm horizon:
Hue-10YR or 7.5YR
Value-3 or 4 moist, 4 through 7 dry
Chroma-1 through 4 moist and dry
Rock fragments - 25 to 60 percent
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: The Grousehill soils are on ridges and benches at elevations of 4,500 to 7,000 feet. The soil formed in volcanic ash over glacial till. Slopes are 0 to 35 percent. Climate is characterized by cold wet winters and cool dry summers. The average annual precipitation is 45 to 70 inches, mainly as snow. The average annual air temperature is 38 to 42 degrees F. The frost-free period is 10 to 35 days.
GEOGRAPHICALLY ASSOCIATED SOILS: This is the Llaorock soils. Llaorock soils are on bedrock knobs and are medial-skeletal.
DRAINAGE AND PERMEABILITY: Moderately well drained; moderate permeability.
USE AND VEGETATION: These soils are used for and recreation, wildlife habitat and timber production . Vegetation consists of Douglas fir, shasta red fir, white fir, mountain hemlock, incense cedar and an understory of many varieties of forbs and shrubs.
DISTRIBUTION AND EXTENT: Cascade Mountains of central Oregon; MLRA 3. The series is not extensive.
MLRA OFFICE 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 the mineral surface to 39 inches (A, Bw1 and Bw2 horizons)
Ochric epipedon
Cambic horizon - 10 to 39 inches (Bw1 and Bw2 horizons)
Cemented glacial till - 39 to 56 inches (Bqm horizon)
Volcanic ash is from Mt. Mazama.
Particle-size control section - from the mineral surface to the duripan.
Soil temperature regime - Cryic
Soil moisture regime - Udic
This series will be reclassified to the Oxyaquic subgroup when the subgroup is approved. A proposal for recognition was sent on July 2000.