LOCATION HARTNER CAEstablished Series
TAXONOMIC CLASS: Ashy, glassy, nonacid, frigid, shallow Vitrandic Torriorthents
TYPICAL PEDON: Hartner very gravelly ashy sandy loam--rangeland (Colors are for dry soil unless otherwise noted.)
A--0 to 1 inches; brown (10YR 5/3) crushed very gravelly ashy sandy loam, brown (10YR 4/3) crushed moist; weak thin platy structure; soft, very friable, nonsticky, nonplastic; few very fine roots; many very fine interstitial pores; 40 percent pebbles; neutral, (pH 7.0); clear smooth boundary. (1 to 4 inches thick)
C--1 to 4 inches; grayish brown (10YR 5/2) crushed gravelly ashy sandy loam, very dark grayish brown (10YR 3/2) crushed moist; massive; soft, very friable, nonsticky, nonplastic; common very fine roots; many very fine interstitial pores; 10 percent paragravel and 25 percent pebbles; neutral, (pH 7.0); clear wavy boundary. (2 to 8 inches thick)
Cr--4 to 8 inches; weathered and fractured tuff-breccia;
TYPE LOCATION: Modoc County California on the Modoc National Forest; 150 feet north and 2,100 feet east of the southwest corner of section 30, T 42N, R 16E; Cedarville 7.5 minute topographic quadrangle; 41 degrees, 28 minutes, 19 seconds north latitude and 120 degrees, 11 minutes, 29.9 seconds west longitude, NAD 27.
RANGE IN CHARACTERISTICS:
Soil moisture - These soils are usually moist in winter and spring, dry in summer and fall; aridic bordering on xeric moisture regime.
Mean annual soil temperature - 43 to 47 degrees F.
Depth to bedrock 4 to 10 inches.
Oxalate extractable Al + 1/2 Fe: 0.2 to 0.4 percent.
Volcanic glass content - 50 to 80 percent in the coarse silt through fine sand fractions.
Profile reaction - Slightly acid or neutral.
Control section - Clay content: 10 to 18 percent.
Rock fragments: 15 to 35 percent rock fragments; mainly pebbles. Lithology of fragments is volcanic rocks such as andesitic tuff, andesite and tuff-breccia.
A horizon - Hue: 10YR or 7.5 YR
Value: 4 or 5 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Organic matter content: 1 to 2 percent.
C horizon - Hue: 10YR or 7.5YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist; darker colors are a result of lithochromic influence, not organic matter.
Structure: Massive or subangular blocky.
Rock fragments: 15 to 35 percent, mainly pebbles; pebbles less than 20mm in size are up to half the total volume. Paragravel and paracobbles that break down to fine pebbles are common, ranging up to 50 percent.
Organic matter content: 0.5 to 0.75 percent.
COMPETING SERIES: This is the Morganhills (OR) series. Morganhills soils have tuffaceous sandstone bedrock at depths between 10 and 20 inches, have 5 to 8 inch thick sola, and lithology of the rock fragments is tuffaceous sandstone.
GEOGRAPHIC SETTING: Hartner soils are on backslopes of mountains. They formed in colluvium and residuum derived from volcanic ash and andesite, andesitic tuff, tuff-breccia and similar volcanic rocks. Slopes are 4 to 75 percent. Elevations range from 4,690 to 7,160 feet. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 16 to 24 inches but effective moisture is low due to the very shallow, droughty soil and steep slopes. Mean annual temperature is 43 to 45 degrees F., and the frost-free period is 60 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Fendersflat and the Sesdah soils. Fendersflat soils have more than 35 percent rock fragments and are 20 to 40 inches deep. Sesdah soils are 14 to 20 inches deep to bedrock, have a mollic epipedon and an argillic horizon.
DRAINAGE AND PERMEABILITY: Well drained; high surface runoff; moderately rapid permeability.
USE AND VEGETATION: Hartner soils are used for livestock grazing, watershed and wildlife habitat. The present vegetation is mainly a very sparse stand of mountain big sagebrush, bluebunch wheatgrass, purple sage, antelope bitterbrush, Indian ricegrass and Sierra juniper.
DISTRIBUTION AND EXTENT: Eastern Modoc County, California, Surprise Valley-Home Camp Area. These soils are not extensive. MLRA 21.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Surprise Valley-Home Camp Area, California and Nevada, 2005.
REMARKS: The series type location was moved to better reflect the concept. The classification is changed from Argixerolls to Torriorthents, which better represents the thin, unstable soils of the area.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 4 inches (A and C horizons).
Paralithic contact - The boundary at 4 inches to underlying soft bedrock (Cr layer).
Vitrandic intergrade feature - High volcanic glass content in the .02 to 2mm fraction from the mineral soil surface to 25 inches (A and C horizons).
Particle-size control section - The zone from about 0 to 4 inches (A and C horizons).