LOCATION EMERALDLAKE CAEstablished Series
The Emeraldlake series consists of very deep, somewhat excessively drained soils that formed in tephra mixed with colluvium from volcanic rocks. Emeraldlake soils are on cirque walls, volcanic domes, colluvial aprons and mountain slopes in the Southern Cascade mountains. Slopes range from 15 to 95 percent. The mean annual precipitation is about 117 inches (2972 mm) and the mean annual temperature is about 39 degrees F (4 degrees C).
TAXONOMIC CLASS: Ashy-skeletal, amorphic, nonacid Vitrandic Cryorthents
TYPICAL PEDON: Emeraldlake, extremely gravelly ashy fine sandy loam, on a southwest facing (214 degrees) slope of 60 percent, under a cover of mountain monardella, purple needlegrass, pinemat manzanita, mountain hemlock, and whitebark pine at an elevation of 8497 feet, (2591 m). When described on 9/19/06, the soil was dry throughout. (Colors are for dry soil unless otherwise noted).
A1--0 to 1 inches (0 to 3 cm); grayish brown (2.5Y 5/2) extremely gravelly ashy fine sandy loam, very dark grayish brown (2.5Y 3/2) moist; 2 percent clay; single grain; loose, nonsticky, nonplastic; 30 percent subangular fine gravel, 30 percent subangular medium and coarse gravel; strongly acid, pH 5.5 by Hellige-Truog; NaF 9.0; abrupt smooth boundary.
A2--1 to 5 inches (3 to 12 cm); grayish brown (2.5Y 5/2) extremely gravelly ashy loamy sand, very dark grayish brown (2.5Y 3/2) moist; 2 percent clay; single grain; loose, nonsticky, nonplastic; many very fine and fine roots and few medium roots; few fine interstitial and many very fine interstitial pores; 9 percent subangular fine gravel, 44 percent subangular medium gravel, 7 percent subangular cobbles; moderately acid, pH 6.0 by Hellige-Truog; NaF pH 10.0; abrupt smooth boundary.
A3--5 to 14 inches (12 to 35 cm); light brownish gray (10YR 6/2) extremely gravelly ashy loamy sand, dark grayish brown (10YR 4/2) moist; 3 percent clay; single grain; loose, nonsticky, nonplastic; many very fine and fine, and common medium roots; common fine tubular, common medium and many very fine interstitial pores; 5 percent subangular fine gravel, 45 percent subangular medium and coarse gravel and 15 percent subangular cobbles; slightly acid, pH 6.5 by Hellige-Truog; NaF 10.9; abrupt wavy boundary. (Combined thickness of the A horizon is 2 to 14 inches, (5 to 35 cm) thick)
Bw1--14 to 25 inches (35 to 64 cm); light yellowish brown (10YR 6/4) extremely gravelly ashy loamy coarse sand, brown (10YR 4/3) moist; 2 percent clay; weak fine and medium subangular blocky structure; soft, very friable, nonsticky, nonplastic; few coarse and common very fine to medium roots; few fine tubular, many very fine and fine, and few medium interstitial pores; 10 percent subangular fine gravel, 55 percent subangular medium and coarse gravel, and 10 percent subangular cobbles; neutral, pH 6.7 by Hellige-Truog; NaF 11.2; abrupt smooth boundary.
Bw2--25 to 35 inches (64 to 90 cm); light yellowish brown (10YR 6/4) extremely gravelly ashy loamy coarse sand, dark yellowish brown (10YR 4/4) moist; 3 percent clay; weak medium subangular blocky structure parting to single grain; soft, very friable, nonsticky, nonplastic; common fine and medium, few coarse and few very fine roots; common very fine to medium interstitial pores; 12 percent subangular fine gravel, 45 percent subangular medium gravel, 10 percent subangular cobbles, and 10 percent subangular stones; neutral, pH 6.8 by Hellige-Truog; NaF pH 11.0; clear smooth boundary.
Bw3--35 to 51 inches (90 to 129 cm); very pale brown (10YR 7/4) ashy boulders, dark yellowish brown (10YR 4/4) moist; 3 percent clay; single grain; loose, nonsticky, nonplastic; few very fine to coarse roots; common fine and medium interstitial pores; 3 percent subangular fine gravel, 23 percent subangular medium and coarse gravel, 5 percent subangular cobbles, 25 percent subangular stones, and 40 percent subangular boulders; neutral, pH 6.8 by Hellige-Truog; NaF pH 11.1; abrupt smooth boundary.
Bw4--51 to 60 inches (129 to 152 cm); very pale brown (10YR 7/4) ashy boulders, dark yellowish brown (10YR 4/4) moist; 1 percent clay; single grain; loose, nonsticky, nonplastic; few medium and coarse roots; common fine and medium interstitial pores; 3 percent subangular fine gravel, 23 percent subangular medium and coarse gravel, 30 percent subangular stones, and 40 percent subangular boulders; neutral, pH 6.8 by Hellige-Truog; NaF pH 11.3 (Combined thickness of the Bw horizon is 44 to 48 inches (112 to 122 cm) or more thick)
TYPE LOCATION: Shasta County, California, about 0.3 miles west of the southernmost corner of the Lassen Peak Trail parking lot, approximately 1,200 feet east and 2,100 feet north of the southwest corner of sec 11, T. 30 N, R. 4 E, 40 degrees, 28 minutes, 25 seconds north latitude and 121 degrees, 30 minutes, 39 seconds west longitude, NAD83; USGS Quad: Lassen Peak, California.
RANGE IN CHARACTERISTICS:
Depth to restrictive feature: Bedrock greater than 60 inches (152 cm).
Mean annual soil temperature: 40 to 43 degrees F (4.4 to 6.0 degrees C).
Soil moisture control section is dry: July to October (about 90 days).
Particle-size control section (thickest part): 1 to 4 percent clay, and 75 to 77 percent rock fragments.
Surface fragments: 10 to 45 percent gravel, 5 to 45 percent cobbles, 5 to 20 percent stones, and 3 to 15 percent boulders.
Some pedons have Bq, C, or Cq horizons.
Upper A horizon:
Color dry: 2.5Y 5/2, 6/2, 10YR 5/2, 6/2
Color moist: 2.5Y 3/2, 10YR 3/2
Texture: extremely gravelly ashy fine sandy loam, gravelly ashy sandy loam, gravelly ashy coarse sandy loam, very gravelly ashy coarse sandy loam
Clay content: 1 to 4 percent
Rock fragments: 13 to 30 percent fine gravel, 14 to 38 percent medium and coarse gravel, 28 to 60 percent total gravel, 0 to 10 percent cobbles, 30 to 65 percent total rock fragments
Organic matter: 4.5 to 8 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 11.0
Soil reaction: slightly acid to strongly acid
Lower A horizon:
Color dry: 2.5Y 5/2 10YR 6/2, 6/3
Color moist: 2.5Y 3/2, 10YR 4/2
Texture: extremely gravelly ashy loamy sand, very gravelly ashy loamy coarse sand, extremely gravelly ashy loamy coarse sand
Clay content: 1 to 4 percent
Rock fragments: 5 to 16 percent fine gravel, 35 to 55 percent medium and coarse gravel, 50 to 66 percent total gravel, 5 to 15 percent cobbles, 0 to 7 percent stones, 55 to 80 percent total rock fragments
Organic matter: 4 to 7 percent
Acid oxalate extractable Al plus 1/2 Fe: 0.35 to 0.5
P retention: 30 to 50
Glass content: 18 to 30 percent
NaF pH: 9.2 to 11.2
Soil reaction: slightly acid or moderately acid
Upper Bw horizon:
Color dry: 10YR 6/3, 6/4, 2.5Y 6/2, 6/3
Color moist: 10YR 3/3, 3/4, 4/3, 4/4, 2.5Y 3/3
Texture: extremely gravelly ashy sandy loam, extremely gravelly ashy loamy coarse sand, very cobbly ashy fine sandy loam
Clay content: 2 to 4 percent
Rock fragments: 7 to 14 percent fine gravel, 17 to 55 percent medium and coarse gravel, 24 to 65 percent total gravel, 10 to 20 percent cobbles, 0 to 10 percent stones, 45 to 88 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: 10.5 to 11.8
Soil reaction: neutral or slightly acid
Lower Bw horizon:
Color dry: 10YR 6/3, 6/4, 7/3, 7/4, 7.5YR 7/2
Color moist: 10YR 4/3, 4/4, 7.5YR 4/2
Texture: ashy Boulders, very gravelly ashy loamy sand, extremely gravelly ashy coarse sand
Clay content: 1 to 4 percent
Rock fragments: 3 to 15 percent fine gravel, 8 to 55 percent medium and coarse gravel, 26 to 60 percent total gravel, 0 to 15 percent cobbles, 2 to 30 percent stones, 0 to 40 percent boulders, 55 to 96 percent total rock fragments
Organic matter: 1.5 to 4 percent
Acid oxalate extractable Al plus 1/2 Fe: 1.4 to 1.8
P retention: 70 to 90
Glass content: 18 to 25 percent
NaF pH: 10.5 to 11.8
Soil reaction: neutral or slightly acid
COMPETING SERIES: There are no other series in this family.
GEOGRAPHIC SETTING: Emeraldlake soils are on cirque walls, volcanic domes, colluvial aprons and mountain slopes in the Southern Cascade mountains. Slopes are 15 to 95 percent. These soils formed in tephra mixed with colluvium from volcanic rocks. Elevation is 6471 to 10450 feet (1973 to 3186 m). Mean annual precipitation is 53 to 125 inches (1346 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 Readingpeak and Terracelake soils. The Readingpeak soils are deep to bedrock and are on convex backslopes of mountain flanks. The Terracelake soils are moderately deep to bedrock and are on convex positions on mountain tops and flanks.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Somewhat excessively drained; saturated hydraulic conductivity is high to very high.
USE AND VEGETATION: This soil is used for wildlife habitat, recreation, ecosystem management and watershed. Vegetation is mountain monardella, purple needlegrass, pinemat manzanita, mountain hemlock, and whitebark pine.
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 Emerald Lake in Lassen Volcanic National Park.
REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon: 0 to 14 inches, (0 to 35 cm)
Andic soil properties: 14 to 60 inches, (35 to 152 cm)
Particle-size control section: 10 to 40 inches, (25 to 102 cm)
Soil moisture control section: 20 to greater than 60 inches, (51 to greater than 152 cm)
ADDITIONAL DATA:
Reference samples from lab pedon number 08N0485 NSSL, Lincoln, NE. NASIS User Pedon ID in Davis, MLRA Office: 789208.