LOCATION MASTERSON CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, micaceous, mesic Humic Dystroxerepts
TYPICAL PEDON: Masterson gravelly loam - forested. (Colors are for dry soil unless otherwise noted.)
01--2 to 1/2 inches; loose litter of red and white fir needles and twigs.
02--1/2 to 0 inches; very dark brown, partially decomposed organic matter.
A11--0 to 7 inches; brown (7.5YR 5/3) gravelly loam, dark brown (7.5YR 3/2) moist; strong medium granular structure; soft, very friable, nonsticky, nonplastic; many fine roots; many fine and medium pores; gravel is platy schistose and angular quartzite fragments; soil has distinct "talcy" feel; strongly acid (pH 5.3); gradual smooth boundary. (5 to 8 inches thick)
A12--7 to 11 inches; brown (7.5YR 5/3) gravelly loam, dark brown (7.5YR 3/3) moist; strong medium granular structure; soft, very friable, nonsticky, nonplastic; many fine roots; many fine pores; soil has "talcy" feel; strongly acid (pH 5.3); clear smooth boundary. (3 to 6 inches thick)
B2--11 to 21 inches; brown (7.5YR 5/3) very gravelly loam, dark brown (7.5YR 4/4) moist; moderate medium granular structure; soft, very friable, nonsticky. nonplastic; many fine roots; many fine and medium pores: few thin patchy clay films line pores; coarse fragments increase in size and quantity with depth; soil has "talcy" feel; very strongly acid (pH 5.0); clear wavy boundary. (8 to 20 inches thick)
C1--21 to 35 inches; light yellowish brown (10YR 6/4) very gravelly loam, yellowish brown (10YR 5/4) moist; moderate medium and coarse granular structure; soft, very friable, nonsticky, nonplastic: few fine and medium roots; many fine and medium pores; distinct "talcy" feel; very strongly acid (pH 4.5); abrupt irregular boundary. (4 to 20 inches thick)
R--35 to 38 inches; shattered and partially weathered, strongly folded sericite schist with numerous thin quartzite seams; a few roots follow fracture lines.
TYPE LOCATION: Glenn County, California; on Brushy Mountain, 2-1/2 miles south of Plaskett Guard Station; SW1/4 sec. 2, T.21N., R.9W.
RANGE IN CHARACTERISTICS: Depth to a lithic contact is usually 30 to 40 inches and ranges from 20 to 40 inches. The soil between depths of about 5 to 15 inches is usually continually moist from sometime in October until sometime in June and is usually dry all the rest of the year. The mean annual soil temperature at depth of 20 inches is about 53 to 56 degrees F. Most pedons are loam throughout. The amount of coarse fragments increases with increasing depth below a depth of 10 inches, coarse fragments average 35 to 55 percent of the volume. The A horizon is brown (10YR 5/3, 4/3, 7.5YR 5/2, 5/3, 5/4, 4/2, 4/4) dry with chroma and value of 2 or 3 moist. It is sandy loam or loam and contains 2 to 8 percent organic matter. This horizon has moderate or strong granular or crumb structure. It is usually medium or strongly acid and has less than 50 percent base saturation, but in some pedons the upper few inches are slightly acid. The B2 horizon is brown, strong brown, or yellowish brown dry in 10YR or 7.5YR hue and has chroma of 4 through 6 moist or dry. It is loam or sandy loam and contains 1 to 3 percent more clay than the A horizon. This horizon has very few to common thin clay films lining some pores. It is strongly to very strongly acid and has moderate or weak structure. The C horizon is similar to the B horizon and may be thin and nearly indistinguishable from it. This horizon is light yellowish brown or closely related color in 10YR or 7.5YR hue.
COMPETING SERIES: These are the Hugo, Madonna, Sheetiron, and Washougal series. Hugo and Madonna soils lack umbric epipedons and have less than 35 percent coarse fragments. Sheetiron soils lack the thickness and color requirements of an umbric epipedon. Washougal soils have mixed mineralogy and lack a lithic contact at depths of 40 inches or less.
GEOGRAPHIC SETTING: Masterson soils are on rolling to steep slopes at elevations of about 5,000 to 6,500 feet. They formed in residuum weathered from mica schist, characteristically sericite schist. The climate is moist subhumid with warm dry summers and cool moist winters. Mean annual precipitation is 40 to 60 inches. Annual snowfall is about 50 to 70 inches. The mean annual temperature is about 48 to 50 degrees F., average January temperature is about 30 to 32 degrees F., and average July temperature is about 65 degrees F. The freeze-free season is about 110 to 150 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Boomer and Yollabolly soils and the competing Sheetiron soils. Boomer soils have reddish argillic horizons. Yollabolly soils are less than 20 inches deep to hard rock.
DRAINAGE AND PERMEABILITY: Well-drained; medium to rapid runoff; moderate or moderately rapid permeability.
USE AND VEGETATION: Used for forestry. Native vegetation is red fir, white fir, Douglas-fir, ponderosa pine, and sugar pine.
DISTRIBUTION AND EXTENT: Higher elevations in the northern part of the Coast Ranges in California and possibly in Oregon. The series is extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Glenn County, California, 1957.
REMARKS: The Masterson soils were formerly classified as Yellowish Brown Lateritic soils. The definition of the series has been changed slightly so as to include only those pedons with thicker A1 horizons that qualify as umbric epipedons.
OSED scanned by SSQA. Last revised by state on 3/72.