LOCATION MARTIS CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Ultic Haploxeralfs
TYPICAL PEDON: Martis gravelly sandy loam - on a north facing slope of 2 percent under big sagebrush at 5,775 feet elevation. (Colors are for dry soil unless otherwise stated. When described on 7/2/73 the soil was moist below 17 inches).
A11--0 to 7 inches; dark brown (10YR 4/3) sandy loam, dark brown (7.5YR 3/2) moist; moderate fine and medium granular structure; soft, very friable, nonsticky and nonplastic; few fine, common very fine roots; many very fine interstitial pores; 10 percent pebbles; strongly acid (pH 5.5); clear wavy boundary. (3 to 7 inches thick)
A12--7 to 17 inches; brown (10YR 4/3) sandy loam, dark brown (7.5YR 3/2) moist; moderate fine and medium granular structure; soft, friable, slightly sticky and slightly plastic; few very fine and medium roots; many very fine interstitial pores; 5 percent pebbles; strongly acid (pH 5.5); clear wavy boundary. (3 to 10 inches thick)
B21t--17 to 23 inches; brown (10YR 5/3) gravelly sandy clay loam, dark brown (7.5YR 3/2) moist; moderate fine and medium subangular blocky structure; slightly hard, firm, sticky and slightly plastic; few fine roots; few very fine interstitial and discontinuous tubular pores; few thin clay films as bridges and lining pores, very few moderately thick clay films as bridges; 5 percent stones, 5 percent cobbles, 20 percent pebbles; strongly acid (pH 5.5); abrupt wavy boundary. (6 to 12 inches thick)
B22t--23 to 33 inches; brown (10YR 5/3) gravelly light sandy clay loam, dark brown (7.5YR 3/2) moist; massive; hard, firm, sticky and slightly plastic; few fine roots; few very fine vesicular and discontinuous tabular pores; very few moderately thick clay films lining pores and as bridges, common thin clay films as bridges; 7 percent cobbles, 15 percent pebbles; moderately acid (pH 6.0); clear wavy boundary. (8 to 13 inches thick)
B31t--33 to 46 inches; brown (10YR 5/3) gravelly sandy clay loam, dark yellowish brown (10YR 3/4) moist; massive; hard, firm, sticky and plastic; few medium fine roots; few very fine tubular pores; few thin and moderately thick clay films as bridges; 20 percent pebbles; moderately acid (pH 6.0); clear wavy boundary. (6 to 14 inches thick)
B32t--46 to 67 inches; brown (10YR 5/3) sandy loam, dark yellowish brown (10YR 4/4) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; few discontinuous tubular pores; few thin and moderately thick clay films line pores and as bridges; 10 percent pebbles; moderately acid (pH 6.0). (15 to 24 inches thick)
TYPE LOCATION: Nevada County, Tahoe National Forest, California; 4 miles northeast of Truckee; 1,000 feet southwest of the south end of Prosser Dam near the center of the SW 1/4, SE 1/4 sec. 25, T.18N., R.16E., MDB&M.
RANGE IN CHARACTERISTICS: The solum is 40 to 70 inches thick. The umbric epipedon is 10 to 20 inches thick and in some pedons includes the upper B horizon. Base saturation is 35 to 50 percent. Mean annual soil temperature is 41 degrees to 45 degrees F. The mean summer soil temperature is 59 degrees to 62 degrees F., but in some pedons that have 0 horizons, the mean summer soil temperature is 49 degrees to 53 degrees F. The soil is dry between depths of 8 to 24 inches from mid-July through mid-October, and moist in all parts the rest of the year. Pedons under open stands of timber have thin 0 horizons.
The A horizon has color of 10YR 3/2, 4/2, 4/3 or 5/3 dry, and 7.5YR 2/2, 3/2, 3/3; 10YR 3/1, 3/2, or 3/3 moist. It is sandy loam or loam with 5 to 20 percent gravel. This horizon has granular, subangular blocky, or thick platy structure. It is slightly to strongly acid.
The upper part of the B2t horizon has color of 7.5YR 5/4; 10YR 5/2, 5/3, 5/4, 6/3 or 6/4 dry, and 7.5YR 3/2, 4/3, 4/4; 10YR 3/3, 3/4 or 4/4. It is sandy clay loam or heavy sandy loam with 18 to 27 percent clay, 15 to 30 percent gravel, and 3 to 5 percent cobbles. This horizon has subangular blocky structure or is massive and has high bulk density in most pedons. It is moderately to strongly acid. The lower part of the Bt horizon has colors of 7.5YR 4/4, 5/4; 10YR 5/3, 6/3, 6/4 dry and 7.5YR 3/2; 10YR 3/4, 4/3, 4/4 and 5/4 moist. It is sandy clay loam or sandy loam and has 3 to 20 percent cobbles and 10 to 80 percent gravel. Rock fragments increase with increasing depth and exceed 35 percent below 32 inches in some pedons.
COMPETING SERIES: These are the Fugawee, Ketchly, Kruse, McEwen, Mimus, Tahoma, Tepping, and Wintoner series. Fugawee soils are less than 40 inches deep to a paralithic contact. Ketchly soils have very hard and extremely hard B2t and C horizons, are slightly acid and neutral and have 20 to 60 percent ash in the solum. Kruse soils have ochric epipedons and heavy loam and clay loam B2t horizons. McEwen soils have control sections with 27 to 35 percent clay, ochric epipedons, and silt loam A horizons. Mimus soils have ochric epipedons and less than 10 percent coarse fragments in the B2t horizon. Tahoma soils have ochric epipedons and base saturation less than 35 percent in the lower part of the argillic. Tepping soils have 0 to 5 percent rock fragments in the control section. Wintoner soils have less than 15 percent coarse fragments and more than 25 percent clay in the control section.
GEOGRAPHIC SETTING: Martis soils are on gently sloping glacial outwash plains. Elevations are 5,500 to 6,000 feet. Slopes are 2 to 5 percent. They formed in mixed glacial outwash dominated by volcanic material. The climate is typified by warm dry summers and cold moist winters. Mean annual precipitation ranges from 25 to 35 inches. Mean annual temperature is from 40 degrees to 45 degrees F., mean January temperature is 24 degrees F., and mean July temperature is about 60 degrees F. The average frost-free season is 20 to 40 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Euer, Kyburz and Trojan soils. Euer soils have more than 35 percent coarse fragments in the control section and sola less than 40 inches thick. Kyburz soils are less than 40 inches deep to a paralithic contact and Trojan soils have mollic epipedons.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderately slow permeability.
USE AND VEGETATION: Used for housing, grazing, wildlife habitat, and recreation. Vegetation is sagebrush and bitterbrush. Jeffrey and lodgepole pine occur on pedons with less dense subhorizons.
DISTRIBUTION AND EXTENT: Intermountain valleys of the northeastern Sierra Nevada Mountains in California. The soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Nevada County (Tahoe National Forest Area), California, 1973.
REMARKS: The activity class was added to the classification in February of 2003. Competing series were not checked at that time. - ET
OSED scanned by SSQA. Last revised by state on 5/81.