LOCATION GLEASON CAEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, frigid Entic Haploxerolls
TYPICAL PEDON: Gleason gravelly sandy loam - forest (Colors are for dry soil unless otherwise stated.)
Oi--1 to 0 inches; Litter of pine needles
A11--0 to 4 inches; grayish brown (10YR 5/2) gravelly sandy loam, dark grayish brown (10YR 3/2) moist; moderate very fine crumb structure; loose, very friable, nonsticky, nonplastic; many very fine roots; many very fine interstitial pores; 37 percent by volume obsidian gravel; slightly acid (pH 6.5); clear smooth boundary. (1 to 7 inches thick)
A12--4 to 16 inches; grayish brown (10YR 5/2) sandy loam, very dark grayish brown (10YR 3/2) moist; massive; soft, very friable, nonsticky, nonplastic; common very fine roots; many very fine interstitial and tubular pores; less than 10 percent by volume obsidian gravel; moderately acid (pH 6.0); clear wavy boundary. (9 to 13 inches thick)
AC--16 to 22 inches; grayish brown (10YR 5/2) sandy loam, dark yellowish brown (10YR 3/4) moist; massive; slightly hard, very friable, nonsticky, nonplastic; few very fine and fine, common medium and few coarse roots; many very fine interstitial and common very fine tubular pores; less than 10 percent by volume obsidian gravel; moderately acid (pH 6.0); gradual wavy boundary. (5 to 12 inches thick)
C1--22 to 35 inches; light gray (10YR 7/2) gravelly sandy loam, brown (10YR 5/3) moist; massive; slightly hard, friable, nonsticky, nonplastic; few fine roots, common coarse roots; many very fine interstitial pores; 15 percent gravel by volume; slightly acid (pH 6.2); gradual smooth boundary. (10 to 14 inches thick)
C2--35 to 50 inches; very pale brown (10YR 7/3) very gravelly coarse sand, light yellowish brown (10YR 6/4) moist; massive; hard, firm, nonsticky, nonplastic; few fine roots; few very fine interstitial pores; 50 percent gravel of weathered tuff; slightly acid (pH 6.2); gradual smooth boundary. (13 to 16 inches thick)
R--50 to 56 inches; pale brown (10YR 6/3) hard tuff agglomerate.
TYPE LOCATION: Modoc County, California; about 8 miles north of Davis Creek; 30 feet south and 90 feet west of the east quarter corner of section 10, T.46N., R.14E.
RANGE IN CHARACTERISTICS: Depth to a lithic contact of hard tuff is 40 to 60 inches. The mean annual soil temperature is about 41 degrees to 47 degrees F. and mean summer soil temperature ranges widely depending upon the tree canopy density and thickness of the 0 horizons. Under a thick canopy and at least a 3-inch 0 horizon the mean summer soil temperature is about 47 degrees to 50 degrees F.., while under an open canopy with no 0 horizon it is about 59 degrees to 63 degrees F. The soil temperature is below 41 degrees F. from December 1 to April 30. The soil between depths of 10 to 24 inches is usually dry in all parts from July 15 until October 15 and is moist in some or all parts all the rest of the year. It is moist in all parts from December 15 to May 1. Rock fragments make up 15 to 40 percent of the upper part of the A horizon and averages less than 35 percent of the 10- to 40-inch control section. The lower part of the A horizon and upper part of the C horizon have about 10 to 20 percent rock fragments and the lower C horizon contains up to 70 percent. Most fragments are volcanic, including obsidian and tuff. The soil is slightly and/or moderately acid throughout. The organic matter commonly is 1 to 1.5 percent at a depth of 20 inches in the lower A horizon but the horizon has a moist value or chroma of 4.
The A11 horizon is grayish brown, dark grayish brown, gray, or dark gray dry and dark brown, very dark brown, very dark grayish brown, or black moist in 10YR hue. It is sandy loam or loam and has crumb or subangular blocky structure or is massive. This horizon is soft or slightly hard.
The A12 horizon is light brownish gray, grayish brown, brown or light brown (10YR or 7.5YR 6/2 or 5/2) dry and dark yellowish brown to brown (10YR or 7.5YR 4/4, 4/3, 4/2, or 3/4) moist.
The C horizon is very pale brown, light gray, or pinkish gray in 10YR or 7.5YR hue dry and light yellowish brown to brown (10YR 6/4, 6/3, 5/4, 5/3; 7.5YR 6/4, 5/4) moist. It is sandy loam, loamy coarse sand, or coarse sand. The lower part of the C horizon gradually grades to hard rock.
COMPETING SERIES: These are the Windy and Woodcock series. Windy soils are dominated by pyroclastic materials and have cindery control sections. Woodcock soils have mollic epipedons deeper than 20 inches, cryic temperature regimes, and have loamy-skeletal control sections.
GEOGRAPHIC SETTING: Gleason soils are strongly sloping to steep mountains at elevations of 4,500 to 5,800 feet. They formed in residuum from tuffs, agglomerates and rhyolites. These soils are influenced by pyroclastic materials but have less than 60 percent. The climate is subhumid mesothermal with cool to warm, dry summers and cold, moist winters. Mean annual precipitation is 17 to 22 inches. Snowfall is 30 to 50 inches. Average January temperature is 27 degrees F.; average July temperature is 60 degrees to 65 degrees F.; mean annual temperature is 45 degrees to 50 degrees F. The freeze-free season is 70 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Woodcock soils and the Bieber, Kinkel and Puls soils. Bieber and Puls soils have clayey control sections and have duripans of depths of less than 20 inches. Kinkel soils have ochric epipedons, have an argillic horizon and have loamy-skeletal control sections. They also have a mesic temperature regime.
DRAINAGE AND PERMEABILITY: Well-drained; medium to rapid runoff; moderately rapid permeability.
USE AND VEGETATION: Used mostly for woodland and range. Vegetation is Jeffrey pine, dogwood, mountain mahogany, bitterbrush, rabbit brush and bluebunch wheat grasses, fescue, and squirreltail.
DISTRIBUTION AND EXTENT: Northeastern California in Modoc County, principally in the Warner Mountains. The soils are inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Alturas Area, California, 1931.
REMARKS: These soils were formerly classified as Brown Forest soils. In some pedons a weak expression of a cambic horizon is present but it is not recognized as part of the series at this time. The classification is changed from Typic Haploxerolls to Entic Haploxerolls. As originally mapped this series included soils with argillic horizons, cambic horizons and fine-loamy control sections. These are now excluded.
The activity class was added to the classification in February of 2003. Competing series were not checked at that time. - ET
ADDITIONAL DATA: Riverside laboratory pedon No. S72 Calif 25-12, not published to date.
OSED scanned by SSQA. Last revised by state on 6/74.