LOCATION PFEIFFER CAEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, thermic Typic Haploxerolls
TYPICAL PEDON: Pfeiffer gravelly coarse sandy loam, under annual grasses. (Colors are for dry soil unless otherwise noted.)
A11--0 to 6 inches; dark yellowish brown (10YR 4/4) gravelly coarse sandy loam, dark brown (10YR 3/3) moist; moderate fine granular structure; soft, friable, nonsticky and nonplastic; many fine roots; many very fine and fine interstitial pores; about 20 percent angular gravel, mostly 2 to 20 mm but range to 76 mm; neutral (pH 6.6); clear wavy boundary. (3 to 11 inches thick)
A12--6 to 16 inches; brown (10YR 4/3) gravelly coarse sandy loam, dark brown (10YR 3/3)moist; moderate medium and fine granular and weak very coarse subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine interstitial and common fine tubular pores; about 25 percent angular gravel, mostly 2 to 20 mm, but ranges to 76 mm; slightly acid (pH 6.4); clear wavy boundary. (8 to 11 inches thick)
A13--16 to 24 inches; brown (10YR 4/3) gravelly coarse sandy loam, dark brown (7.5YR 3/3) moist; moderate fine granular structure; soft, very friable, nonsticky and nonplastic; common very fine roots; many fine interstitial and common fine tubular pores; about 30 percent angular gravel, mostly 2 to 20 mm, but range to 76 mm; slightly acid (pH 6.4); clear wavy boundary. (8 to 21 inches thick)
A14--24 to 36 inches; brown (10YR 4/3) gravelly coarse sandy loam, dark brown (7.5YR 3/3) moist; massive; soft, very friable, nonsticky and nonplastic; common very fine roots; many fine interstitial and common tubular pores about 30 percent angular gravel, mostly 2 to 20 mm, but range to 76 mm; slightly acid (pH 6.4); gradual wavy boundary. (0 to 12 inches thick)
B21--36 to 55 inches; strong brown (7.5YR 4/6) very gravelly coarse sandy loam, dark brown (7.5YR 3/3) moist; massive; soft, friable, nonsticky and nonplastic; common very fine roots; many fine interstitial and common fine tubular pores; about 45 percent angular gravel and 5 percent cobblestones; slightly acid (pH 6.4); gradual wavy boundary. (7 to 18 inches thick)
B22--55 to 60 inches; strong brown (7.5YR 4/6) very gravelly coarse sandy loam, dark brown (7.5YR 3/3) moist; massive; soft, friable, nonsticky and nonplastic; common very fine roots; many fine interstitial and common fine tubular pores; about 50 percent angular gravel, mostly 40 to 76 mm;, and 5 percent cobblestones; slightly acid (pH 6.5); gradual wavy boundary. (0 to 6 inches thick)
Cr--60 to 70 inches; weathered and fractured gneissic granitic bedrock.
TYPE LOCATION: Monterey County, California; about 1 mile south, southwest from Nacimiento Guard Station (U.S.F.S.), 350 feet down the ridge from Nacimiento-Ferguson Road; about 750 feet west, 300 feet south from northeast corner of section 30, T.22S., R.5E.
RANGE IN CHARACTERISTICS: Depth to a paralithic contact is 40 to 70 inches. The mean annual soil temperature at a depth of 20 inches is 59 to 64 degrees F. The soil between the depths of about 9 to 27 inches is usually moist all of the time from about the middle of October until about the middle of May and is dry all the rest of the time. Rock fragments average 10 to 35 percent in the 10 to 40 inches control section. Most of these fragments are less than 3/4 inch in diameter. The amount and size of rock fragments increase with depth and most pedons have more than 35 percent rock fragments below a depth of 40 inches. Organic matter is 1.5 to 2.5 percent in the upper 10 inches and decreases gradually to less than 1 percent at a depth of 20 inches. The soils are sandy loam or coarse sandy loam throughout and are neutral or slightly acid throughout.
The A horizon is brown, dark brown , or dark yellowish brown (10YR 5/3, 4/3, 4/4) dry and dark brown or very dark grayish brown (10YR 3/3, 3/2; 7.5YR 3/2) moist.
The B horizon is brown, dark brown, or strong brown (7.5YR 5/4, 4/4, 5/6, 4/6) dry. Some pedons have a few thin clay films.
COMPETING SERIES: These are the Andregg and San Andreas series in the same family and the Ben Lomond, Junipero,and Sheridan series in other families. Andregg and San Andreas soils are 24 to 40 inches deep to granitic rocks or sandstone. Ben Lomond and Junipero soils have a mean annual soil temperature cooler than 59 degrees F. and have a base saturation of 50 to 75 percent in some part of the soil to a depth of 30 inches. Sheridan soils have a dark colored A horizon with more than 1 percent organic matter to a depth of 20 inches or more.
GEOGRAPHIC SETTING: These soils are on footslopes and mountainous uplands at elevations of 300 to 2,800 feet. They formed in material weathered from sandstones, schists, gneiss, and granitic rocks. The climate is moist subhumid with warm, dry summers and cool, moist winters. The mean annual precipitation ranges from 25 to 55 inches. The mean annual temperature is about 49 degrees F.; and the average July temperature is about 75 degrees F. The frost free season ranges from 225 to 300 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing San Andreas and Sheridan soils and the Arnold, Cieneba, Gaviota, Gazos, Sur and Vista soils. Arnold soils lack mollic epipedons and have sandy texture. Cienba soils have a paralithic contact at depths of less than 20 inches. Gazos soils have more than 18 percent clay. Sur soils have more than 35 percent rock fragments in the control section. Vista soils lack mollic epipedons.
DRAINAGE AND PERMEABILITY: Well drained; slow to very rapid runoff; moderately rapid permeability.
USE AND VEGETATION: Used mostly for grazing, watershed, wildlife, and recreation. Naturalized vegetation is annual grasses and forbs, few oaks, and small amounts of brush.
DISTRIBUTION AND EXTENT: Central part of the Coast Range in California. Th soils are inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Monterey County, California, 1972.
REMARKS: The activity class was added to the classification in February of 2003. Competing series were not checked at that time. - ET