LOCATION NEEDAPEPPER CAEstablished Series
The Needapepper series consists of very deep, well drained soils that formed in dominantly volcanic alluvium derived from mixed sources. Needapepper soils are on fan piedmont remnants. Slopes are 2 to 8 percent. The mean annual precipitation is about 356 millimeters and the mean annual temperature is about 7 degrees C.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Pachic Argixerolls
TYPICAL PEDON: Needapepper very gravelly sandy loam --Rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with 40 percent gravel and 5 percent cobbles.
A--0 to 5 centimeters; dark grayish brown (10YR 4/2) very gravelly sandy loam, very dark brown (10YR 2/2) moist; weak fine subangular blocky structure parting to moderate fine granular structure; soft, very friable, nonsticky and nonplastic; common very fine roots; many very fine interstitial pores; 35 percent subangular gravel; slightly acid (pH 6.4); clear smooth boundary. (5 to 10 centimeters thick)
Bt1--5 to 20 centimeters; dark grayish brown (10YR 4/2) gravelly sandy loam, very dark brown (10YR 2/2) moist; weak medium and coarse subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; common fine and medium roots and many very fine roots; common very fine interstitial and common very fine tubular pores; 5 percent faint clay bridges between sand grains; 15 percent subangular gravel; neutral (pH 6.7); clear wavy boundary. (10 to 25 centimeters thick)
Bt2--20 to 43 centimeters; dark grayish brown (10YR 4/2) gravelly sandy clay loam, very dark brown (10YR 2/2) moist; moderate medium and coarse subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine to coarse roots; common very fine tubular and common very fine interstitial pores; 25 percent faint clay bridges between sand grains; 15 percent subangular gravel; neutral (pH 6.9); clear wavy boundary. (15 to 30 centimeters thick)
Bt3--43 to 86 centimeters; grayish brown (10YR 5/2) gravelly sandy clay loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; slightly hard, very friable, moderately sticky and moderately plastic; common very fine and fine roots; common very fine tubular and common very fine interstitial pores; 25 percent faint clay bridges between sand grains; 15 percent subangular gravel; neutral (pH 7.0); clear wavy boundary. (36 to 50 centimeters thick)
Bt4--86 to 117 centimeters; brown (7.5YR 5/2) and dark grayish brown (10YR 4/2) gravelly sandy clay loam, dark brown (7.5YR 3/2) moist and very dark brown (10YR 2/2) moist; moderate fine and medium subangular blocky structure; hard, very friable, moderately sticky and moderately plastic; few very fine and fine roots; common very fine tubular and common very fine interstitial pores; 25 percent faint clay bridges between sand grains; 20 percent subangular gravel; neutral (pH 7.0); clear wavy boundary. (20 to 36 centimeters thick)
Bt5--117 to 152 centimeters; brown (7.5YR 5/2) gravelly sandy clay loam, very dark brown (7.5YR 2/2) moist; weak medium subangular blocky structure; hard, very friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine tubular and common very fine interstitial pores; 5 percent faint clay bridges between sand grains; 15 percent subangular gravel; neutral (pH 7.0).
TYPE LOCATION: Mono County, California; in Slinkard Valley about 5.95 kilometers southwest of the Junction of CA state route 89 and US highway 395; Coleville USGS 7.5 minute topographic quadrangle; 38 degrees 36 minutes 43.0 seconds north latitude and 119 degrees 35 minutes 08.1 seconds west longitude, NAD 83.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually moist in the moisture control section; moist winter and spring; usually dry July through early October; Xeric moisture regime, bordering on Aridic.
Mean annual soil temperature - 7 to 8 degrees C.
Mollic epipedon thickness - 10 to 152 centimeters.
Depth to base of argillic horizon - greater than 152 centimeters.
Control section - Clay content: Averages 18 to 27 percent.
Rock fragments: Averages 15 to 35 percent, mainly gravel. Lithology of rock fragments are dominantly volcanic rock, with some granitic and metamorphic rock.
A Horizon - Value: 4 or 5 dry, 2 or 3 moist.
Organic matter content: 2 to 4 percent.
Reaction: Slightly acid or neutral.
Bt1 and Bt2 Horizons - Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3 dry or moist.
Texture: Gravelly sandy clay loam, gravelly sandy loam.
Clay content: 18 to 27 percent.
Rock fragments: 15 to 35 percent.
Organic matter content: 1 to 3 percent
Reaction: Neutral
Bt3 and Bt4 Horizons - Hue: 7.5YR or 10YR.
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3 dry or moist.
Texture: Gravelly sandy clay loam, gravelly loam or gravelly sandy loam.
Clay content: 18 to 25 percent when averaged.
Rock fragments: 15 to 35 percent when averaged.
Organic matter content: 1 to 3 percent.
Reaction: Neutral.
Bt5 Horizon (when present) - Hue: 7.5YR or 10YR.
Value: 5 dry, 2 or 3 moist.
Chroma: 2, 3 or 4 dry or moist.
Texture: Gravelly sandy clay loam or gravelly loam.
Clay content: 18 to 27 percent when averaged.
Rock fragments: 15 to 35 percent when averaged.
Organic matter content: 0.5 to 2 percent.
Reaction: Neutral
COMPETING SERIES: These are the Carey Lake, Dunford, Hades, Hurryback, Krueger, Lagnaf, Mahogan, Marotz, Moffspring, Nagle, Sag, Strom and Tusk series. Carey Lake soils are less than 76 centimeters to the base of their Bt horizons and have 2C horizons. Dunford and Mahogan soils have lithic contacts at depths of 50 to 100 centimeters. Hades soils have secondary carbonates at depths of 137 to 152 centimeters and 25 to 35 percent clay in their Bt horizons. Lagnaf soils have depth to the base of the argillic horizon less than 127 centimeters and have C horizons with more than 35 percent rock fragments. Marotz soils have the top of the argillic at depths of 51 to 89 centimeters and have 25 to 35 percent clay in their particle size control section. Hurryback, Krueger, Moffspring, Nagle, Sag, Strom and Tusk soils have a mollic epipedon 50 to 100 centimeters thick.
GEOGRAPHIC SETTING: Needapepper soils are on Fan piedmont remnants. They formed in dominantly volcanic alluvium derived from mixed rock sources. Slopes are 2 to 8 percent. Elevations range from 1,676 to 1,981 meters. The climate is semi-arid with cool, moist winters and warm, dry summers. The mean annual precipitation is 350 to 400 millimeters, mean annual temperature is 6 to 8 degrees C., and the frost-free period is 60 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Chrisflat, Noodler and Slinkard soils. Chrisflat and Slinkard soils have greater than 35 percent rock fragments in the particle size control section. Noodler soils have more than 35 percent clay in the particle size control section.
DRAINAGE AND PERMEABILITY: Well drained; medium surface runoff; moderate permeability (moderately high and high saturated hyraulic conductivity).
USE AND VEGETATION: Needapepper soils are used for rangeland, livestock grazing, watershed and wildlife habitat. The native vegetation is mainly mountain big sagebrush, antelope bitterbrush and western needlegrass.
DISTRIBUTION AND EXTENT: Eastern California, east of the Sierra Nevada Range in the western part of the Great Basin. These soils are not extensive. MLRA 22.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES PROPOSED: Mono County (Coleville-Bridgeport Area), California, 2008.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from soil surface to more than 152 centimeters (A, Bt1, Bt2, Bt3, Bt4 and Bt5 horizons).
Argillic horizon - The zone from 5 to more than 152 centimeters (Bt1, Bt2, Bt3, Bt4 and Bt5 horizons).
Particle-size control section - The zone from 5 to 55 centimeters (Bt1, Bt2 and upper Bt3 horizons).