LOCATION SIBELIA NVEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic Xeric Humicryepts
TYPICAL PEDON: Sibelia very cobbly sandy loam--forestland. (Colors are for dry soil unless otherwise noted.)
Oi/Oe--0 to 18 centimeters; slightly to moderately decomposed plant material composed of pine litter and duff; abrupt smooth boundary. (3 to 18 centimeters thick)
A--18 to 33 centimeters; grayish brown (10YR 5/2) very cobbly sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; many fine through coarse roots; many very fine and fine interstitial, and many fine through medium tubular pores; 10 percent gravel, 15 percent cobbles, and 10 percent stones; slightly acid (pH 6.4); clear wavy boundary. (15 to 25 centimeters thick)
Bw--33 to 53 centimeters; light yellowish brown (10YR 6/4) very gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine, fine, and common medium roots; many very fine through medium tubular pores; 30 percent gravel and 5 percent cobbles; slightly acid (pH 6.4); gradual wavy boundary. (15 to 30 centimeters thick)
C1--53 to 69 centimeters; pale brown (10YR 6/3) very gravelly sandy loam, brown (10YR 4/3) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; many fine, and common medium roots; many very fine thru medium tubular pores; 30 percent gravel and 5 percent cobbles; neutral (pH 6.6); gradual wavy boundary. (8 to 30 centimeters thick)
C2--69 to 122 centimeters; pale brown (10YR 6/3) extremely cobbly sandy loam, brown (10YR 4/3) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few fine and medium roots; common very fine and fine tubular pores; 35 percent gravel, 20 percent cobbles, and 5 percent stones; neutral (pH 6.8); clear wavy boundary. (38 to 71 centimeters thick)
C3--122 to 137 centimeters; pale brown (10YR 6/3) extremely cobbly sandy loam, brown (10YR 4/3) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; few fine and medium roots; common very fine and fine tubular pores; 30 percent gravel and 30 percent cobbles; neutral (pH 6.8); clear wavy boundary. (0 to 30 centimeters thick)
Cr--137 centimeters; weathered and fractured andesite.
TYPE LOCATION: Washoe County, Nevada; on the Toiyabe National Forest in the Carson Range south of Mount Rose; about 2,000 feet west and 500 feet south of the northeast corner of section 23, T. 17 N., R. 18 E.; USGS Mount Rose 7.5 minute topographic quadrangle; latitude 39 degrees 19 minutes 44.67 seconds N. and longitude 119 degrees 55 minutes 37.69 seconds W., NAD83.
RANGE IN CHARACTERISTICS:
Umbric epipedon thickness - 18 to 25 centimeters; includes the A horizon and part of the Bw horizon when the upper 18 centimeters of the mineral soil is mixed.
Depth to base of cambic horizon - 36 to 61 centimeters.
Depth to bedrock - 102 to 152 centimeters to a paralithic contact measured from the mineral soil surface. The paralithic materials below the contact are weathered andesite or andesitic tuff-breccia.
Soil moisture - Usually moist in the moisture control section during late fall, winter, and spring; dry from mid-July through September for 60 to 80 consecutive days in the four months following the summer solstice; Typic xeric moisture regime.
Mean annual soil temperature - 4 to 7 degrees C.
Mean summer soil temperature - 7 to 8 degrees C.
Particle-size control section - Clay content: 10 to 18 percent;
Rock fragments: Averages 35 to 70 percent, mainly cobbles and gravel. Lithology of fragments are volcanic rocks such as andesite or tuff-breccia.
Reaction: Moderately acid through neutral.
Base saturation: 10 to 30 percent by the ammonium acetate method.
Other features - The O horizon constitutes a folistic epipedon when thickness is 15 to 18 centimeters.
A horizon - Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Organic matter content: 3 to 5 percent.
Bw horizon - Hue: 2.5Y or 10YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 4 through 6, dry or moist.
Organic matter content: 1 to 3 percent.
C horizons - Hue: 2.5Y or 10YR.
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 4 through 6, dry or moist.
Texture: Very cobbly sandy loam, extremely cobbly sandy loam, or extremely gravelly sandy loam.
Rock fragments: 50 to 75 percent total; 20 to 40 percent gravel and 30 to 35 percent cobbles.
COMPETING SERIES: These are the
Callat,
Fishsnooze,
Florand,
Forsell,
Lostridge,
Sonorapass, and
Sumeadow series.
Callat soils are moderately deep to densic contacts. Fishsnooze and Sonorapass soils are moderately deep to lithic contacts. Florand soils have depth to base of the cambic horizon of 89 to 114 centimeters and do not have horizons in the particle-size control section that are dominated by cobbles. Forsell and Sumeadow soils are very deep. Lostridge soils are moderately deep to paralithic contacts.
GEOGRAPHIC SETTING: Sibelia soils are on mountains. They typically occur on footslope and backslope positions. Slopes are 15 to 50 percent. They formed in residuum and colluvium derived mainly from andesite. Elevation is 2,438 to 3,048 meters. The mean annual precipitation is 889 to 1270 millimeters. The mean annual temperature is 3 to 6 degrees C. The frost-free period is 30 to 50 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Macareeno and Meiss soils. Macareeno soils are somewhat poorly drained. Meiss soils are 25 to 50 centimeters deep and are not skeletal.
DRAINAGE AND PERMEABILITY: Well drained; medium surface runoff; moderately rapid permeability (high saturated hydraulic conductivity).
USE AND VEGETATION: Sibelia soils are used for forestland and watershed. The vegetation is a forest canopy of whitebark pine and western white pine with an understory of mountain big sagebrush, mountain brome, and bottlebrush squirreltail.
DISTRIBUTION AND EXTENT: Western Nevada on the east side of the Sierra Nevada Range. These soils are not extensive with about 2,300 acres of the series mapped to date. MLRA 22A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Washoe County, Nevada, South Part, 1980.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Folistic epipedon - The zone from the soil surface to 18 centimeters (Oi/Oe horizon).
Umbric epipedon - The zone from 18 to 36 centimeters (A horizon and part of the Bw horizon).
Cambic horizon - The zone from 33 to 53 centimeters (Bw horizon).
Paralithic contact - The boundary at 137 centimeters to underlying weathered bedrock (Cr layer).
Particle size control section - The zone from 25 to 100 centimeters (Bw and C1 horizons and parts of the A and C2 horizons).
ADDITIONAL DATA: A pedon of Sibelia near the series type location is sampled for full characterization by the Soil Survey Laboratory (SSL), Lincoln, NE, as user pedon number 79NV031030 (pedon # 79P0484).