LOCATION TERRACELAKE CAEstablished Series
The Terracelake series consists of moderately deep, well drained soils that formed in tephra over or mixed with colluvium and residuum from volcanic rock. Terracelake soils are on glaciated volcanic domes, glaciated mountain slopes, glaciated lava flows, scoured glacial-valley walls and floors, and roche moutenees in the Southern Cascade mountains. Slopes range from 1 to 95 percent. The mean annual precipitation is about 99 inches (2515 mm) and the mean annual temperature is about 41 degrees F (5 degrees C).
TAXONOMIC CLASS: Ashy-skeletal, amorphic Xeric Vitricryands
TYPICAL PEDON: Terracelake gravelly ashy sandy loam, on a south facing (195 degrees) slope of 34 percent, under a cover of pinemat manzanita at an elevation of 7590 feet, (2313 m). When described on 8/1/2007, the soil was dry throughout. (Colors are for dry soil unless otherwise noted).
Oi--0 to 1 inches (0 to 3 cm); leaf and twig litter; abrupt smooth boundary.
A--1 to 3 inches (3 to 7 cm); dark grayish brown (10YR 4/2) gravelly ashy sandy loam, very dark brown (10YR 2/2) moist; 3 percent clay; moderate thick and very thick platy parting to moderate coarse granular structure; many very fine and fine roots; common very fine and fine tubular and many very fine and fine irregular pores; 12 percent subangular fine gravel, 5 percent subangular medium and coarse gravel; strongly acid, pH 5.5 by Hellige-Truog; NaF pH 9.2; abrupt smooth boundary. (1 to 4 inches (2 to 10 cm) thick)
2Ab--3 to 7 inches (7 to 18 cm); brown (10YR 5/3) gravelly ashy sandy loam, brown (10YR 4/3) moist; 4 percent clay; weak very fine to medium subangular blocky structure parting to single grain; many very fine to coarse roots; many very fine and fine irregular, many very fine tubular and few medium tubular pores; 15 percent subangular fine gravel and 18 percent subangular medium and coarse gravel; moderately acid, pH 6.0 by Hellige-Truog; NaF pH 11.5; abrupt smooth boundary. (3 to 13 inches (8 to 33 cm) thick)
2Bwb1--7 to 19 inches (18 to 49 cm); pale brown (10YR 6/3) very gravelly ashy fine sandy loam, brown (10YR 4/3) moist; 5 percent clay; weak very fine and fine subangular blocky structure parting to single grain; many very fine and fine, common medium, and many coarse and very coarse roots; many very fine and fine irregular and common very fine tubular pores; 13 percent subangular fine gravel, 27 percent subangular medium and coarse gravel, and 15 percent subangular cobbles; slightly acid, pH 6.3 by Hellige-Truog; NaF pH 11.7; abrupt irregular boundary.
2Bwb2--19 to 24 inches (49 to 62 cm); very pale brown (10YR 7/3) extremely gravelly ashy fine sandy loam, dark yellowish brown (10YR 4/4) moist; 6 percent clay; weak very fine to medium subangular blocky structure parting to single grain; many very fine and fine, common medium, and many coarse and very coarse roots; many very fine and fine interstitial and irregular, and common fine tubular pores; 15 percent subangular fine gravel, 25 percent subangular medium and coarse gravel, 20 percent subangular cobbles, and 2 percent subangular stones; slightly acid, pH 6.3 by Hellige-Truog; NaF pH 11.4; abrupt wavy boundary. (Combined thickness of the Bw horizon is 7 to 31 inches (18 to 79 cm) thick)
2Bqb--24 to 37 inches (62 to 95 cm); pale brown (10YR 6/3) extremely stony ashy sandy loam, brown (10YR 4/3) moist; 3 percent clay; massive; common very fine and fine roots between rock fragments; common very fine to medium irregular pores; 10 percent threadlike silica masses around rock fragments; 7 percent subangular fine gravel, 27 percent subangular medium and coarse gravel, 15 percent subangular cobbles, and 40 percent subangular stones; slightly acid, pH 6.3 by Hellige-Truog; NaF pH 11.4; abrupt wavy boundary. (0 to 13 inches (33 cm) thick)
2R--37 to 41 inches (95 to 104 cm) dacite bedrock
TYPE LOCATION: Shasta County, California, about 1 mile east north east of the Kings Creek Picnic Area, approximately 1,450 feet south and 500 feet east of the northwest corner of sec 17, T. 30 N, R. 5 E, 40 degrees, 27 minutes, 51 seconds north latitude and 121 degrees, 27 minutes, 26 seconds west longitude, NAD83; USGS Quad: Reading Peak, California.
RANGE IN CHARACTERISTICS:
Depth to restrictive feature: Lithic contact 20 to 40 inches (51 to 102 cm).
Mean annual soil temperature: 40 to 43 degrees F (4 to 6 degrees C).
Soil moisture control section is dry: July to October (about 90 days).
Particle-size control section (thickest part): 3 to 6 percent clay, and 60 to 89 percent rock fragments.
Surface fragments: 0 to 75 percent gravel, 3 to 30 percent cobbles, 0 to 25 percent stones, and 0 to 20 percent boulders.
A horizon:
Color dry: 10YR 3/2, 4/2, 5/2, 6/2, 6/3, 2.5Y 4/2
Color moist: 10YR 3/1, 2/2, 3/2, 4/2, 4/3
Texture: ashy loamy very fine sand, ashy loamy coarse sand, gravelly ashy loamy coarse sand, ashy very fine sandy loam, gravelly ashy fine sandy loam, gravelly ashy sandy loam, very gravelly ashy fine sandy loam, very gravelly ashy sandy loam, very bouldery ashy sandy loam
Clay content: 2 to 6 percent
Rock fragments: 0 to 27 percent fine gravel, 0 to 23 percent medium and coarse gravel, 0 to 50 percent total gravel, 0 to 35 percent cobbles, 0 to 10 percent stones, 0 to 10 percent boulders, 8 to 60 percent total rock fragments
Organic matter: 5.5 to 10 percent
Base saturation by ammonium acetate: 3 to 20 percent
Acid oxalate extractable Al plus 1/2 Fe: 0.35 to 0.5
P retention: 20 to 30
Glass content: 15 to 20 percent
NaF pH: 9.0 to 11.7
Soil reaction: strongly acid to slightly acid
2Ab horizon:
Color dry: 10YR 5/2, 6/2, 5/3, 2.5Y 6/3
Color moist: 10YR 3/2, 4/2, 4/3
Texture: gravelly ashy sandy loam, very gravelly ashy sandy loam, extremely gravelly ashy coarse sandy loam
Clay content: 3 to 5 percent
Rock fragments: 10 to 20 percent fine gravel, 16 to 40 percent medium and coarse gravel, 33 to 58 percent total gravel, 0 to 12 percent cobbles, 0 to 5 percent stones, 0 to 10 percent boulders, 33 to 68 percent total rock fragments
Organic matter: 3 to 5 percent
Acid oxalate extractable Al plus 1/2 Fe: 1.4 to 1.8
P retention: 60 to 85
Glass content: 18 to 25 percent
NaF pH: 10.4 to 11.5
Soil reaction: strongly acid to slightly acid
2Bwb horizon:
Color dry: 10YR 5/4, 5/6, 6/3, 6/4, 6/6, 7/3, 7/4, 2.5Y 6/4
Color moist: 7.5YR 4/3, 4/4, 10YR 3/3, 3/4, 3/6, 4/3, 4/4, 2.5Y 4/3
Texture: very gravelly ashy fine sandy loam, very gravelly ashy sandy loam, extremely gravelly ashy fine sandy loam, extremely gravelly ashy sandy loam, extremely gravelly ashy coarse sandy loam, very cobbly ashy fine sandy loam, extremely cobbly ashy fine sandy loam, extremely stony ashy sandy loam, ashy stones
Clay content: 2 to 10 percent
Rock fragments: 1 to 26 percent fine gravel, 6 to 45 percent medium and coarse gravel, 18 to 61 percent total gravel, 5 to 50 percent cobbles, 0 to 25 percent stones, 0 to 10 percent boulders, 44 to 90 percent total rock fragments
Organic matter: 2 to 4 percent
Acid oxalate extractable Al plus 1/2 Fe: 1.4 to 1.8
P retention: 70 to 95
Glass content: 18 to 25 percent
NaF pH: 10.6 to 12.0
Soil reaction: slightly acid or neutral
2Bqb horizon:
Color dry: 10YR 6/3, 7/2, 7.5YR 8/3
Color moist: 10YR 4/3, 5/3, 7.5YR 5/4
Texture: very gravelly ashy loamy sand, extremely gravelly ashy coarse sandy loam, extremely stony ashy fine sandy loam, extremely stony ashy sandy loam
Clay content: 2 to 9 percent
Rock fragments: 5 to 35 percent fine gravel, 26 to 45 percent medium and coarse gravel, 34 to 61 percent total gravel, 0 to 20 percent cobbles, 0 to 40 percent stones, 0 to 10 percent boulders, 55 to 89 percent total rock fragments
Organic matter: 0.5 to 1.5 percent
Acid oxalate extractable Al plus 1/2 Fe: 1.4 to 1.8
P retention: 70 to 95
Glass content: 18 to 25 percent
NaF pH: 11.0 to 11.4
Soil reaction: slightly acid or neutral
COMPETING SERIES: These are the Readingpeak and Wardcreek soils. Readingpeak soils are deep to a lithic contact. Wardcreek soils have 5 to 15 percent glass throughout the profile, rock fragments average 35 to 60 percent in the particle-size control section and do not have a lithological discontinuity.
GEOGRAPHIC SETTING: Terracelake soils are on glaciated volcanic domes, glaciated mountain slopes, glaciated lava flows, scoured glacial-valley walls and floors, and roche moutenees in the Southern Cascade mountains. Slopes are 1 to 95 percent. These soils formed in tephra over or mixed with colluvium and residuum from volcanic rock. Elevation is 5720 to 10450 feet (1744 to 3186 m). Mean annual precipitation is 55 to 125 inches (1397 to 3175 mm). The mean annual temperature is 39 to 41 degrees F (4 to 5 degrees C). Frost free season is 50 to 85 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Acroph, Shadowlake, Readingpeak and Emeraldlake soils. The Acroph soils are shallow to bedrock. The Shadowlake soils are deep to dense till. The Readingpeak soils are deep to bedrock. The Emeraldlake soils are very deep.
DRAINAGE AND PERMEABILITY: Well drained; saturated hydraulic conductivity is high to very high in the A and 2Bqb horizons, and high in the 2Ab and 2Bwb horizons.
USE AND VEGETATION: This soil is used for wildlife habitat, recreation, ecosystem management and watershed. Vegetation is pinemat manzanita, California red fir, western white pine, buckwheat, lodgepole pine, mountain hemlock, lupine, white fir, and grasses.
DISTRIBUTION AND EXTENT: The soils are inextensive and are mapped in MLRA: 22B, Southern Cascade Mountains
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: 2009 Shasta County, California. Source of name from Terrace Lake in Lassen Volcanic National Park.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: 1 to 3 inches, (3 to 7 cm)
Cambic horizon: 3 to 24 inches, (7 to 62 cm)
Andic soil properties: 3 to 37 inches, (7 to 95 cm)
Lithic contact: 37 inches, (95 cm)
Particle-size control section: 1 to 37 inches, (3 to 95 cm)
Soil moisture control section: 12 to 37 inches, (31 to 95 cm)
ADDITIONAL DATA:
Classification and properties inferred from lab data from lab pedon number 08N0485 NSSL, Lincoln, NE. NASIS User Pedon ID in Davis, MLRA Office: 789322.