LOCATION MORBENCH                NV

Established Series
Rev. JBF/WED/RLB
06/2016

MORBENCH SERIES

The Morbench series consists of very deep, well drained soils that formed in alluvium derived from mixed rocks. Morbench soils are on fan remnants. Slopes are 4 to 30 percent. The mean annual precipitation is about 330 mm and the mean annual temperature is about 10 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Durinodic Xeric Haplocalcids

TYPICAL PEDON: Morbench gravelly sandy loam--woodland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with approximately 40 percent gravel and 2 percent with cobbles.

A1--0 to 3 cm; brown (10YR 5/3) gravelly sandy loam, dark brown (10YR 3/3) moist; weak thick platy structure; soft, very friable, nonsticky and nonplastic; few very fine roots; many very fine and fine vesicular pores; 25 percent gravel and 5 percent cobbles; violently effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (0 to 5 cm thick)

A2--3 to 10 cm; brown (10YR 5/3) gravelly sandy loam, dark brown (10YR 3/3) moist; weak thick platy structure parting to weak medium subangular blocky; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and common fine vesicular pores; 15 percent gravel and 5 percent cobbles; violently effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (8 to 20 cm thick)

Bk--10 to 25 cm; brown (10YR 5/3) gravelly sandy loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; soft, very friable, nonsticky and slightly plastic; common very fine and fine and few medium roots; many very fine and fine tubular and common very fine interstitial pores; 25 percent gravel and 5 percent cobbles; soft powdery carbonate in matrix; violently effervescent; moderately alkaline (pH 8.4); gradual smooth boundary. (5 to 15 cm thick)

Bqk1--25 to 74 cm; very pale brown (10YR 7/3) very gravelly sandy loam, yellowish brown (10YR 5/4) moist; massive, soft and slightly hard in spots, very friable and friable in spots, nonsticky and nonplastic; few very fine and many fine, medium and coarse roots; many very fine and fine tubular and common very fine and fine interstitial pores; 40 percent gravel and 5 percent cobbles; soft powdery carbonate in matrix; 10 percent weak silica cementation and 1 mm thick silica lamella; violently effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (38 to 64 cm thick)

Bqk2--74 to 127 cm; very pale brown (10YR 7/3) very gravelly loamy sand, light yellowish brown (10YR 6/4) moist; massive; slightly hard, friable, nonsticky and nonplastic; few medium roots; many very fine and fine and few medium interstitial pores; 45 percent gravel and 5 percent cobbles; 10 percent strong and 50 percent weak discontinuous silica cementation; soft powdery carbonate in matrix; violently effervescent; strongly alkaline (pH 8.8); clear wavy boundary. (38 to 64 cm thick)

Bq--127 to 152 cm; pale brown (10YR 6/3) very gravelly sandy loam, brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; many very fine, fine and medium interstitial pores; 40 percent gravel and 5 percent cobbles; 15 percent weak discontinuous silica cementation; strongly effervescent with noneffervescent spots; moderately alkaline (pH 8.4).

TYPE LOCATION: Nye County, Nevada; about 1,400 feet south and 1,100 feet west of the approximate northeast corner of section 4, T. 9 N., R. 51 E.; USGS Moores Station 7.5 minute topographic quadrangle; latitude 38 degrees 40 minutes 28 seconds N and longitude 116 degrees 14 minutes 00 seconds W; WGS84 Decimal Degrees 38.6742778 latitude, -116.2333333 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture - Usually dry, moist in winter and spring, dry in summer except for 10 to 20 days between July and October due to convection storms; aridic soil moisture regime bordering on xeric.
Mean annual soil temperature: 9 to 11 degrees C.
Thickness of calcic horizon: 89 to 140 cm.
Reaction: Moderately alkaline or strongly alkaline.
Effervescence: Strongly effervescent or violently effervescent.

Particle-size control section - Clay content: 8 to 13 percent.
Rock fragments: Average 35 to 55 percent.

A horizon
Chroma: 2 or 3.

Bk horizon
Value: 5 through 7 dry, 4 through 6 moist.
Chroma: 3 or 4.

Bqk1 horizon
Value: 6 or 7 dry, 4 through 6 moist.
Chroma: 3 through 5.
Consistence: Soft or slightly hard, very friable or friable.
Rock fragments: 35 to 50 percent gravel, 0 to 10 percent cobbles.
Secondary carbonate accumulation: Soft powdery carbonate throughout horizon.
Other features: 10 to 65 percent weak to strong discontinuous silica-carbonate cementation as plates or durinodes.

Bqk2 horizon
Value: 6 or 7 dry, 4 through 6 moist.
Chroma: 3 through 5.
Texture: Loamy sand or sandy loam.
Rock fragments: 35 to 50 percent gravel, 0 to 10 percent cobbles.
Secondary carbonate accumulation: Soft powdery carbonate throughout horizon.
Other features: 20 to 65 percent weak to strong discontinuous silica-carbonate cementation as plates or durinodes.

Bq horizon
Value: 6 or 7 dry, 4 through 6 moist.
Chroma: 3 through 6.
Texture: Sand to sandy loam.
Rock fragments: 35 to 60 percent, mainly gravel.

COMPETING SERIES: These are the Armespan, Automal, Dakent, Pyrat and Sugarcreek series.
Armespan soils have depth to Bqk horizon of 38 to 64 cm and the calcic horizon is less than 90 cm thick. Automal soils are moist in winter and spring and dry from June to mid-October, and also contains 10 to 20 percent clay in the particle-size control section. Dakent soils have soil temperature of 12 to 15 degrees C. and have Bw horizons that contain 10 to 22 percent clay, and that contain 60 to 75 percent gravel. Pyrat soils are moist in winter and spring and dry from June to mid-October, are not moist 10 to 20 days during the summer months and depth to Bk horizon is 36 to 50 cm. Sugarcreek soils are moderately deep to bedrock.

GEOGRAPHIC SETTING: Morbench soils are on fan remnants. These soils formed in alluvium derived from mixed rocks. Slopes are 4 to 30 percent. Elevations are 1,830 to 2,170 meters. The climate is cool, semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 300 to 350 mm, mean annual temperature is 9 to 11 degrees C, and the frost-free season is 100 to 120 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Armespan and the Chuckridge series. Chuckridge soils have both an argillic horizon and duripan.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; medium runoff; moderately low saturated hydraulic conductivity.

USE AND VEGETATION: Wildlife habitat. The present vegetation is mainly pinyon and juniper. The extremely sparse understory is cliffrose, serviceberry and some black sagebrush.

DISTRIBUTION AND EXTENT: South-central Nevada. MLRA 29. These soils are of very limited extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES ESTABLISHED: Nye County, Northeast Part, Nevada, 1993.

REMARKS: Classification changed to Durinodic Xeric Haplocalcids.

Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 18 cm (A1, A2 and part of the Bk horizon).
Calcic horizon - The zone from 25 to 127 cm (Bqk1 and Bqk2 horizons).
Duric horizon - The zone from 25 to 152 cm (Bqk1, Bqk2 and Bq horizons).
Xeric Intergrades - Meets organic requirement for xeric.
Particle-size control section - The zone from 25 to 100 cm (Bqk1, Bqk2 and part of the Bq horizons).

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National Cooperative Soil Survey
U.S.A.