LOCATION GENOA NV
Established Series
Rev. DMC-GJS-JVC-JBF
03/2017
GENOA SERIES
The Genoa series consists of shallow, well drained soils that formed in residuum derived from granitic rocks. Genoa soils are on mountains. Slopes are 4 to 50 percent. The mean annual precipitation is about 380 mm and the mean annual temperature is about 6 degrees C.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Lithic Argixerolls
TYPICAL PEDON: Genoa extremely stony sandy loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with about 20 percent stones.
A--0 to 5 cm; grayish brown (10YR 5/2) extremely stony sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; common fine and many very fine tubular pores; 20 percent fine (2 to 5 mm diameter) gravel, 30 percent medium and coarse (5 to 25 mm diameter) gravel, and 30 percent stones; slightly acid (pH 6.2); abrupt smooth boundary. (5 to 23 cm thick)
Bt1--5 to 15 cm; brown (10YR 5/3) very gravelly sandy clay loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; common very fine and few fine and medium roots; common very fine tubular pores; common faint clay films on faces of peds and lining pores; 20 percent fine (2 to 5 mm diameter) gravel and 30 percent medium and coarse (5 to 25 mm diameter) gravel; neutral (pH 6.6); clear smooth boundary. (5 to 15 cm thick)
Bt2--15 to 30 cm; brown (10YR 5/3) extremely cobbly sandy clay loam, dark brown (10YR 3/3) moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine, and few fine and medium roots; common very fine tubular pores; common distinct clay films on faces of peds and lining pores; 10 percent fine (2 to 5 mm diameter) gravel, 15 percent medium and coarse (5 to 50 mm diameter) gravel, and 45 percent cobbles; neutral (pH 6.8); clear wavy boundary. (13 to 25 cm thick)
Bt3--30 to 48 cm; yellowish brown (10YR 5/4) extremely cobbly sandy clay loam, dark yellowish brown (10YR 3/4) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; few very fine tubular pores; common distinct clay films on faces of peds and lining pores; 5 percent fine (2 to 5 mm diameter) gravel, 20 percent medium and coarse (5 to 50 mm diameter) gravel, 40 percent cobbles, and 15 percent stones; neutral (pH 6.8); abrupt irregular boundary. (10 to 20 cm thick)
R--48 cm; unweathered granitic rock.
TYPE LOCATION: Douglas County, Nevada; in the Pine Nut Mountains east of Galena Saddle; about 0.4 miles north of the south quarter corner of section 22, T. 12 N., R. 22 E.; USGS Pine Nut Valley 7.5 minute topographic quadrangle; latitude 38 degrees 53 minutes 9 seconds N and longitude 119 degrees 30 minutes 4 seconds W; WGS84 Decimal Degrees 38.8857222 latitude, -119.5009722 longitude.
RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist from mid-October through mid-July, dry remainder of summer and early fall for 75 to 90 consecutive days in the four months following the summer solstice; xeric soil moisture regime that borders on aridic.
Mean annual soil temperature: 7 to 8 degrees C.
Mean summer soil temperature: 15 to 17 degrees C.
Mollic epipedon thickness: 25 to 36 cm; includes the Bt1 and Bt2 horizons.
Depth to bedrock; 30 to 50 cm to a lithic contact.
Reaction: Slightly acid or neutral.
Particle-size control section - Clay content: 20 to 30 percent.
Rock fragments: Averages 60 to 80 percent, mainly cobbles. Lithology of fragments are granitic rocks such as granodiorite.
A horizon
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Structure: Weak or moderate, granular or subangular blocky.
Organic matter content: 1 or 2 percent.
Bt horizons
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 1 through 3, dry or moist.
Texture: Extremely cobbly sandy clay loam with very gravelly sandy clay loam or very cobbly loam in the Bt1 horizon.
Rock fragments: 50 to 80 percent, mainly cobbles.
Organic matter content: 1 or 2 percent.
COMPETING SERIES: These are the
Bellenmine,
Celeridge,
Gabica,
Gerdog,
Gidwin,
Grandeposit,
Hawkridge,
Hutchley,
Loope,
Majorsplace,
Mattier,
Melling,
Pernog,
Realmcoy,
Rozara,
Shalcleav, and
Tweener series.
Bellenmine and
Majorsplace soils are intermittently moist in the upper part for 10 to 20 days cumulative due to convection storms between July and September.
Celeridge and
Loope soils have mollic epipedons that are 36 to 50 cm thick, are dominated by gravel in the particle-size control section, and have rock fragments that are volcanic rocks.
Gabica,
Grandeposit,
Mattier,
Realmcoy, and
Tweener soils average 35 to 60 percent rock fragments in the particle-size control section.
Gerdog soils are dominated by gravel in the particle-size control section, have rock fragments that are volcanic rocks, and have mean summer soil temperature of 17 to 19 degrees C.
Gidwin soils have mollic epipedons that are 36 to 50 cm thick and that includes all of the argillic horizon and have rock fragments that are basalt.
Hawkridge soils are dominated by gravel, average 14 to 20 percent clay in the particle-size control section, and have rock fragments that are volcanic rocks.
Hutchley soils have rock fragments that are quartz latite, basalt, or related volcanic rocks.
Melling soils average 35 to 60 percent rock fragments in the particle-size control section and are dry for 45 to 60 consecutive days in the four months following the summer solstice.
Pernog soils are dominated by stones, average 35 to 50 percent rock fragments in the particle-size control section, and have rock fragments that are quartzite, shale, chert, welded tuff, and rhyolite.
Rozara soils are dominated by fine gravel, have 14 to 18 percent clay, and average 45 to 60 percent rock fragments in the particle-size control section.
Shalcleav soils are dominated by channers and flagstones, are 10 to 30 cm to a lithic contact, and have rock fragments that are tuff, rhyolite, chert, or argillite.
GEOGRAPHIC SETTING: Genoa soils are on mountains. They typically occur on convex summit and shoulder positions. These soils formed in residuum derived from granitic and some metamorphic rocks. Slopes are 4 to 50 percent. Elevations range from 2,445 to 2,900 meters. The climate is semiarid with cold, moist winters and warm, dry summers. The mean annual precipitation is 330 to 430 mm and comes mainly as snow. The mean annual temperature is 6 to 7 degrees C. The frost-free period is 50 to 75 days.
GEOGRAPHICALLY ASSOCIATED SOILS: This is the
Glean soil. Glean soils are deep or very deep, have thick mollic epipedons, and do not have argillic horizons.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; very high surface runoff; moderately high saturated hydraulic conductivity.
USE AND VEGETATION: Genoa soils are used for rangeland and wildlife habitat. The present vegetation is Thurber's needlegrass, Sandberg's bluegrass, and low sagebrush.
DISTRIBUTION AND EXTENT: Western Nevada. Genoa soils are not extensive with about 6,000 acres of the series mapped to date. MLRA 26.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Physical survey Carson Valley, Nevada, l940.
REMARKS: The revision of October 2003 updated the taxonomic class from Loamy-skeletal, mixed, superactive Lithic Argicryolls. Local soil temperature data indicates this soil has mean summer soil temperatures in the range of the frigid temperature regime.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 30 cm (A, Bt1, and Bt2 horizons).
Argillic horizon - The zone from 5 to 48 cm (Bt1, Bt2, and Bt3 horizons).
Lithic contact - The boundary at 48 cm to hard, unweathered bedrock (R layer).
Particle-size control section - The zone from 5 to 48 cm (Bt1, Bt2, and Bt3 horizons).
National Cooperative Soil Survey
U.S.A.