LOCATION MARY CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Mollic Haploxeralfs
TYPICAL PEDON: Mary stony loam - on a south facing convex slope of 14 percent under cheatgrass, lupine, medusahead, and Idaho fescue at 2,760 feet elevation. (Colors are for dry soil unless otherwise stated. When described (7/23/75), the soil was dry above 9 inches and moist below.)
A11--0 to 2 inches; dark brown (10YR 4/3) stony loam, very dark grayish brown (10YR 3/2) moist; weak medium platy structure; slightly hard, friable, sticky and plastic; many very fine and fine roots; many fine interstitial pores; 3 percent stones, 3 percent cobbles and 1 percent fine pebbles; neutral (pH 7.2); abrupt smooth boundary. (1 to 4 inches thick)
A12--2 to 10 inches; dark brown (10YR 4/3) stony loam, very dark grayish brown (10YR 3/2) moist; weak medium prismatic structure parting to moderate medium subangular blocky; hard, friable, sticky and plastic; common very fine and fine roots; few very fine and fine tubular and few very fine vesicular pores; 3 percent stones, 1 percent cobbles and 1 percent fine pebbles; neutral (pH 7.2); gradual smooth boundary. (6 to 10 inches thick)
B1t--10 to 17 inches; dark brown (10YR 4/3) loam, very dark grayish brown (10YR 3/2) faces of peds moist; dark brown (10YR 3/3) rubbed moist; weak medium prismatic structure; hard, slightly firm, sticky and very plastic; few very fine and fine roots; few very fine and fine tubular and few very fine vesicular pores; common thin clay films on peds; 1 percent fine pebbles; neutral (pH 7.2); gradual smooth boundary. (5 to 9 inches thick)
B2t--17 to 24 inches; dark yellowish brown (10YR 4/4) clay loam, very dark grayish brown (10YR 3/2) faces of peds moist; dark brown (10YR 3/3) rubbed moist; weak medium prismatic structure; very hard, slightly firm, sticky and very plastic; few very fine and fine roots; few medium, fine and very fine tubular pores; common thin films on peds and many thin clay films in pores; 1 percent cobbles, 1 percent pebbles; neutral (pH 7.2); abrupt wavy boundary. (5 to 10 inches thick)
B3t--24 to 28 inches; dark yellowish brown (10YR 4/4) sandy clay loam, dark brown (10YR 3/3) moist; weak medium prismatic structure; very hard, slightly firm, sticky and very plastic; few very fine and fine roots; few very fine, fine and medium tubular pores; many thin clay films on peds and in pores and few moderately thick films on peds; 1 percent cobbles, 1 percent pebbles; neutral (pH 7.2); abrupt wavy boundary. (3 to 7 inches thick)
R--28 to 32 inches; coarse grained extrusive igneous bedrock.
TYPE LOCATION: Siskiyou County, California; about 8 miles northeast of Montague, California, or 3/4 miles northeast of Marys Peak; 700 feet south and 1,200 feet west of the northeast corner sec. 19, T. 46 N., R. 5 W.
RANGE IN CHARACTERISTICS: The soil is 20 to 40 inches deep to a lithic contact of igneous bedrock. The mean annual soil temperature is 48 to 57 degrees F.; average January soil temperature is 34 to 38 degrees F; average July soil temperature is 64 to 79 degrees F. The soil temperature exceeds 41 degrees F. from March 10 to December 10 and exceeds 47 degrees F. from April 15 to November 20. The soil is dry between the 7 and 18 inch depths from mid-July until mid-October and is moist in some or all parts all the rest of the year. The soil has 0 to 15 percent rock fragments and includes stones, cobbles and pebbles. Organic matter ranges from 1 to 3 percent in the surface 2 to 5 inches, but is less than 1 percent below a depth of 5 inches. The soil is slightly acid or neutral and the base saturation ranges from 80 to 95 percent.
The A horizon is dark grayish brown, dark brown, dark yellowish brown, grayish brown, brown, or yellowish brown (10YR 4/2, 4/3, 4/4, 5/2, 5/3, 5/4; 7.5YR 4/2, 4/4, 5/2, 5/4). Moist colors are very dark brown, very dark grayish brown or dark brown (10YR 2/2, 3/2, 3/3; 7.5YR 3/2). It is sandy loam or loam and averages between 12 and 25 percent clay and is stony in most pedons.
The B2t horizon is dark brown, dark yellowish brown, brown, or yellowish brown (10YR 4/3, 4/4, 5/3, 5/4; 7.5YR 4/4, 5/4). Moist colors are very dark grayish brown to dark yellowish brown (10YR 3/2, 3/3, 3/4, 4/3, 4/4; 7.5YR 3/2, 3/4, 4/4). It is massive in place, but has weak prismatic or subangular blocky structure when displaced. It is heavy loam or clay loam with 20 to 35 percent clay. The clay increase is at least 3 percent absolute or 1.2 times more clay in the B2t horizon than in the A horizon.
The B3t horizon has the same hue and value as the B2t horizon but commonly is a chroma higher. The clay content ranges from 20 to 30 percent.
COMPETING SERIES: These are the Bancas, Blakeport, Bull Trail, Hilt, Morical and Steinbeck series in the same family and the Duzel and Facey series in other families. Bancas soils lack a lithic contact, have soil temperatures above 47 degrees F. by mid-February, and are dry about 180 days. Blakeport soils are medium acid or strongly acid and lack a lithic contact. Bull Trail and Steinbeck soils lack a lithic contact within 40 inches of the surface. Also, Bull Trail soils have a soil temperature above 47 degrees F. by mid-February, and Steinbeck soils have a thick A2 horizon. Duzel soils have a mollic epipedon. Facey soils have a mollic epipedon and lack a lithic or paralithic contact at a depth of 40 inches. Hilt soils have a paralithic contact at depths of 20 to 40 inches and hard bedrock at depths below 40 inches. Morical soils have 20 to 40 percent ash and pumice.
GEOGRAPHIC SETTING: Mary soils are on uplands. Slopes are 2 to 50 percent. The soils formed in material from coarse grained extrusive igneous rock of the Western Cascade Series. The amount of cobbles and/or stones on the soil surface is 0 to 15 percent. Elevations are 2,500 to 4,500 feet. The climate is continental and subhumid with warm to hot dry summers and cold moist winters. Mean annual precipitation is 11 to 18 inches. Seasonal snowfall is 8 to 36 inches. Mean January temperature is 30 to 36 degrees F.;
mean July temperature is 65 to 70 degrees F.; mean annual temperature is 46 to 51 degrees F. Frost-free season is 100 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Jenny, Kuck, Lassen, Louie, Montague, Salisbury, Terwilliger, and the competing Duzel and Hilt soils. The Jenny, Lassen and Montague soils have clay texture and cracks that extend to the surface when dry. The Kuck and Terwilliger soils have a fine argillic horizon. Also, Kuck soils have a mollic epipedon and Terwilliger soils have a paralithic contact. Louie and Salisbury soils have a strongly cemented duripan at depths of 20 to 40 inches.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; moderately slow permeability.
USE AND VEGETATION: Used mainly for rangeland. A few acres are cultivated and produce small grains. Native vegetation is bluebunch wheatgrass, Idaho fescue, Sandberg bluegrass, buckbrush and needlegrass.
DISTRIBUTION AND EXTENT: North-central California. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Siskiyou County, California, 1978.
REMARKS: The color of the A horizon qualifies as a mollic epipedon. However, on the basis of the Hilt and Stoner soil laboratory data, California SSIR No. 24, it is assumed the organic matter is concentrated in the upper 5 inches of the epipedon and is less than 1 percent below 5 inches. Therefore, this soil has an ochric epipedon because it is too thin to qualify for a mollic epipedon.
OSED scanned by SSQA. Last revised by state on 10/78.
The superactive cation exchange activity class was added in 03/2003 to the taxonomic classification by the National Soil Survey Center on request of the Reno MLRA office, without review of the soil series property data. The remainder of this document has not been updated.