LOCATION FREDONYER CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic, frigid Vitrandic Haploxerolls
TYPICAL PEDON: Fredonyer very stony ashy loam--on a 10 percent south-facing slope under curlleaf mountainmahogany, Idaho fescue, and mountain big sagebrush at 5,600 feet elevation--rangeland. (Colors are for dry soil unless otherwise noted. When described on September 15, 1979, the soil was dry to 20 inches and slightly moist below.)
A1--0 to 4 inches; brown (7.5YR 4/2) very stony ashy loam, dark brown (7.5YR 3/2) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine roots; many very fine interstitial pores; 12 percent stones, 5 percent cobbles, and 20 percent gravel, slightly acid (pH 6.1); clear smooth boundary. (2 to 8 inches thick)
A2--4 to 12 inches; brown (7.5YR 4/2) very gravelly ashy loam, dark brown (7.5YR 3/2) moist; weak medium and coarse subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many very fine and few fine roots; many very fine and fine interstitial and tubular pores; 10 percent cobbles and 30 percent gravel; slightly acid (pH 6.5); gradual wavy boundary. (5 to 10 inches thick)
Bw1--12 to 20 inches; brown (7.5YR 5/2) very cobbly loam, dark brown (7.5YR 3/2) moist; moderate medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and fine, few medium and coarse roots; many very fine and common fine tubular pores; 1 percent stones, 25 percent cobbles, and 20 percent gravel; slightly acid (pH 6.5); gradual wavy boundary. (6 to 10 inches thick)
Bw2--20 to 28 inches; brown (7.5YR 5/2) very cobbly loam, dark brown (7.5YR 3/2) moist; moderate medium and coarse angular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine and fine, and few medium roots; many very fine tubular and few fine tubular pores; 20 percent cobbles and 20 percent gravel; slightly acid (pH 6.5); abrupt wavy boundary. (6 to 12 inches thick)
R--28 inches; hard massive andesite; few fractures more than 4 inches apart.
TYPE LOCATION: Lassen County, California; about 34 miles north of Susanville and one mile east of Heavey Mountain; found by traveling about 1 mile north of the Grasshopper fire station, then 1.1 miles west from the intersection of Highway 139 on the dirt road to Heavey Mountain, then about 880 feet north on a tertiary access road, and then about 250 east to the description site; about 300 feet east and 200 feet south of the northwest corner of section 28, T. 34 N., R. 11. E.; USGS Grasshopper Valley 7.5 minute topographic quadrangle; 40 degrees 47 minutes 14 seconds north latitude and 120 degrees 44 minutes 47 seconds west longitude, NAD27.
RANGE IN CHARACTERISTICS:
Soil moisture - The moisture control section is moist in all parts from December 1 to May 15, dry in all parts from August 1 to November 1. The soil temperature exceeds 41 degrees F from May 1 to December 1 and exceeds 47 degrees F from May 15 to November 1; Xeric moisture regime that borders on aridic.
Mean annual soil temperature - 42 to 46 degrees F.
Mollic epipedon thickness - 20 to 40 inches.
Depth to bedrock - 2 to 40 inches to a lithic contact.
Reaction - Slightly acid or neutral.
Particle-size control section - Clay content: 18 to 25 percent; Rock fragments: 40 to 60 percent, mainly cobbles. Lithology of fragments are volcanic rocks such as andesite and basalt.
Other features - Commonly, the surface is covered with about 20 to 50 percent rock fragments.
A horizons - Dry color: 10YR 4/2, 5/2; 7.5YR 5/2, or 4/2.
Moist color: 10YR 2/1, 2/2, 3/2, 3/3; 7.5YR 2/2, 3/2; or 5YR 3/2.
Texture: Very stony ashy loam or stony ashy loam in the A1 horizon and very cobbly ashy loam or very gravelly ashy loam in the A2 horizon.
Structure: Weak or moderate, fine or medium granular or subangular blocky.
Volcanic glass content: 5 to 15 percent.
Oxalate extractable aluminum plus one half extractable iron: 0.5 to 1.0 percent.
Organic matter content: 1 to 3 percent.
Bw horizons - Dry color: 10YR 4/3, 4/4, 5/2, 5/3; 7.5YR 5/2, 5/4; 5YR 4/2, or 4/3.
Moist color: 10YR 3/2, 3/3, 3/4; 7.5YR 3/2, 3/3; 5YR 3/2, or 3/3.
Texture: Very cobbly loam or very gravelly loam.
Organic matter content: 1 or 2 percent.
COMPETING SERIES: These are the Bearspring, Cassal (T), Cherrycreek, Eastpine, Egyptcreek, Longs (T), Midpeak (T), Mineral, Peahke, Scoap, Shalrock (T), Shilling (T), Umatilla, and Yellcreek (T) series.
Bearspring, Cassal, Scoap, Shilling, Umatilla, and Yellcreek soils are very deep. Cherrycreek and Longs soils are deep to lithic contacts. Eastpine, Egyptcreek, Midpeak, Mineral, Peahke, and Shalrock soils have mollic epipedons that are less than 20 inches thick and have underlying cambic horizons.
GEOGRAPHIC SETTING: Fredonyer soils are on mountains and plateaus. They typically occur on all slope positions. These soils formed in surface mantles of volcanic ash over residuum and colluvium derived from basalt or andesite. Slopes are 2 to 50 percent. Elevations range from 5,000 to 7,800 feet. The climate is semiarid with cold, moist winters and warm, dry summers. The mean annual precipitation is 12 to 16 inches including about 20 to 40 inches of snow. The mean January temperature is about 26 degrees F. and the mean July temperature is about 62 degrees F. The mean annual temperature is 43 to 45 degrees F. The frost-free period is 60 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Fivesprings, Jauriga, Petescreek, and Searles soils. Fivesprings and Searles soils have mollic epipedons less than 20 inches thick and have argillic horizons. Jauriga soils are fine-loamy, have argillic horizons, and are deep to paralithic contacts. Petescreek soils are fine-loamy and are moderately deep to paralithic contacts.
DRAINAGE AND PERMEABILITY: Well drained; high surface runoff; moderate permeability.
USE AND VEGETATION: Fredonyer soils are used for rangeland and wildlife habitat. The vegetation is mainly curlleaf mountainmahogany with an understory of Idaho fescue and mountain big sagebrush.
DISTRIBUTION AND EXTENT: Northeastern California. These soils are moderately extensive. MLRA 21.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Butte Valley-Tule Lake Area, California, 1986.
REMARKS: The revision of July 2003 updated the taxonomic class from Loamy-skeletal, mixed, superactive, frigid Pachic Haploxerolls based on laboratory data for the nearby Jauriga and Said series. Oxalate aluminum plus one half extractable iron and volcanic glass content in the A horizons is estimated.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 28 inches (A1, A2, Bw1, and Bw2 horizons).
Vitrandic intergrade feature - The zone from the soil surface to 12 inches (A1 and A2 horizons).
Lithic contact - The boundary at 28 inches to underlying hard, unweathered bedrock (R layer).
Particle-size control section - The zone from 10 to 28 inches (Bw1 and Bw2 horizons and part of the A2 horizon).