LOCATION MILLAN NV
Established Series
Rev. EWB/IJR/WED
02/2012
MILLAN SERIES
The Millan series consists of very deep, well drained soils that formed in alluvium derived dominantly from quartzite with admixtures of limestone and granitic rocks. The Millan soils are on fan remnants. Slopes are 15 to 50 percent. The mean annual precipitation is about 350 mm and the mean annual temperature is about 7 degrees C.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Aridic Argixerolls
TYPICAL PEDON: Millan very gravelly loam--rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is covered with approximately 75 percent gravel and less than 1 percent cobbles and stones.
A1--0 to 8 cm; grayish brown (10YR 5/2) very gravelly loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine roots; many very fine interstitial pores; 35 percent gravel; neutral (pH 7.2); abrupt smooth boundary (5 to 13 cm thick)
A2--8 to 15 cm; grayish brown (10YR 5/2) very gravelly loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium subangular blocky structure; soft, very friable, slightly sticky and nonplastic; many very fine, common fine and medium, and few coarse roots; many very fine interstitial pores; 45 percent gravel; neutral (pH 7.2); abrupt smooth boundary. (5 to 10 cm thick)
Bt1--15 to 25 cm; brown (10YR 5/3) very gravelly clay loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; many very fine, common fine, and few medium and coarse roots; common very fine tubular and interstitial pores; few faint clay films on faces of peds; 45 percent gravel; neutral (pH 7.2); clear wavy boundary. (8 to 18 cm thick)
Btk--25 to 41 cm; pale brown (10YR 6/3) extremely gravelly clay loam, brown (10YR 5/3) moist; moderate medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine and fine, and few medium roots; common very fine tubular and interstitial pores; common distinct clay films on faces of peds; 15 percent secondary calcium carbonate concretions on the bottom of rock fragments; 60 percent gravel; neutral (pH 7.3); clear wavy boundary. (8 to 15 cm thick)
Bk1--41 to 74 cm; pale brown (10YR 6/3) extremely gravelly sandy loam, brown (10YR 5/3) moist; massive; soft, very friable, slightly sticky and nonplastic; common very fine, few fine, medium and coarse roots; common very fine tubular and interstitial pores; 10 percent secondary calcium carbonate concretions on the bottom of rock fragments; 70 percent gravel and 5 percent cobbles; neutral (pH 7.3); clear wavy boundary. (25 to 50 cm thick)
Bk2--74 to 152 cm; very pale brown (10YR 7/3) extremely gravelly sandy loam, brown (10YR 5/3) moist; massive; soft, very friable, nonsticky and nonplastic; common very fine, and few fine and medium roots; common very fine tubular and interstitial pores; 70 percent gravel and 5 percent cobbles; 5 percent secondary calcium carbonate concretions on the bottom of rock fragments; slightly alkaline (pH 7.4).
TYPE LOCATION: White Pine County, Nevada; about 0.5 mile south of Mill Creek northeast of Great Basin National Park; about 2,000 feet north and 1,700 feet east of the southwest corner of section 33 T. 14 N., R. 69E; USGS Lehman Caves 7.5 minute topographic quadrangle; latitude 39 degrees 02 minutes 29 seconds N and longitude 114 degrees 14 minutes 18 seconds W; UTM zone 11 739018e, 4324993n, NAD83.
RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry; moist in winter and spring, dry in all parts at least 45 consecutive days following the summer solstice (July and August), but intermittently moist in the upper part for 10 to 20 days cumulative due to convection storms between July and September; aridic bordering on xeric soil moisture regime.
Mean annual soil temperature: 7 to 8 degrees C.
Mollic epipedon thickness: 25 to 40 cm, including the upper part of the argillic horizon.
Depth to the base of Bt horizon: 25 to 50 cm.
Particle-size control section - Percent clay: 27 to 35 percent.
Rock fragments: 50 to 80 percent, dominantly gravel.
A horizon
Chroma: 2 or 3, dry or moist.
Bt horizons
Value: 5 or 6 dry; 3 through 5 moist; with 5 dry and 3 moist occurring in upper part only.
Chroma: 2 or 3, dry or moist.
Clay content: 27 to 35 percent.
Rock fragments: Averages 50 to 80 percent, with individual horizons ranging from 40 to 80 percent, dominantly gravel.
Bk and/or C horizons
Value: 6 or 7 dry; 4 or 5 moist.
Chroma: 2 or 3, dry moist.
Texture: Sandy loam or loam.
Clay content: Averages 12 to 18 percent.
Rock fragments: 50 to 80 percent, dominantly gravel.
Reaction: Neutral through moderately alkaline.
Effervescence: Non-effervescent or slightly effervescent matrix.
Calcium carbonate equivalent: Typically 0 to 1 percent in less than 2 mm fraction; some pedons have up to 5 percent in Bk horizons.
COMPETING SERIES:
Belate,
Burnborough,
Closkey,
Devils,
Dutchjohn,
Gowjai,
Granipeak,
Jivas,
Sumine, and
Torro series.
Belate soils have bedrock and the base of their Bt horizons at depths of 150 to 203 cm and have 35 to 50 percent rock fragments in their control section.
Burnborough soils are not moist for 10 to 20 days in late summer due to convection storms, the base of Bt horizons is below 100 cm and they have 18 to 25 percent clay in their Bt1 horizons.
Closkey soils have bedrock within 50 to 100 cm and have 35 to 50 percent rock fragments in the particle-size control section.
Devils soils have bedrock within 50 to 100 cm.
Dutchjohn soils have 18 to 27 percent clay and 35 to 50 percent rock fragments in the control section, and are 100 to 150 cm to paralithic contact.
Gowjai soils have bedrock within 100 to 150 cm, the depth to the base of their Bt horizons is 76 to 100 cm and they have silica cemented layers below the Bt horizon.
Granipeak soils have bedrock within 100 to 150 cm, 18 to 25 percent clay in their control section and have rock fragments dominated by boulders and stones.
Jivas soils have bedrock within 100 to 150 cm, have a mollic epipedon that does not include the upper part of the Bt horizon and have argillic horizons 76 to 117 cm.
Sumine soils have bedrock within depths of 50 to 100 cm.
Torro soils have argillic horizons with their base at depths of 60 to 100 cm and the mollic epipedon does not include the upper part of the argillic horizon.
GEOGRAPHIC SETTING: Millan soils are on fan remnants. These soils formed in alluvium derived dominantly from quartzite with admixtures of limestone and granite. Slopes are 15 to 50 percent. Elevations are 1,920 to 2,290 meters. The climate is dry-subhumid with cool moist winters and warm, dry summers. The mean annual precipitation is 300 to 400 mm, mean annual temperature is 6 to 7 degrees C, and the frost-free season is 70 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Bellenmine and
Eenreed series. Bellenmine soils have bedrock within 50 cm. Eenreed soils have a calcic horizon.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; medium to very high runoff; moderately high saturated hydraulic conductivity.
USE AND VEGETATION: Recreation, livestock grazing and wildlife habitat. The potential native vegetation is mainly mountain big sagebrush, bluebunch wheatgrass and Indian ricegrass with a few old singleleaf pinyon and curlleaf mountainmahogany. This site is correlated to Ecological Site R28AY064NV Shallow Loam 10-14 P.Z.
DISTRIBUTION AND EXTENT: East Central Nevada. These soils are not extensive. MLRA 28A.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Phoenix, Arizona
SERIES ESTABLISHED: White Pine County, Nevada, East Part. 2004. The name is coined from a nearby canyon.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the surface to 25 cm (A1, A2 and Bt horizons).
Argillic horizon - The zone from 15 to 41 cm (Bt and Btk horizons).
Particle-size control section - The zone from 15 to 41 cm (Bt and Btk horizons).
National Cooperative Soil Survey
U.S.A.