LOCATION MILKIWAY                NV

Established Series
Rev. EWB-JVC-JBF
04/2017

MILKIWAY SERIES

The Milkiway series consists of very deep, moderately well drained soils that formed in alluvium derived from mixed rocks. Milkiway soils are on stream terraces. Slopes are 0 to 2 percent. The mean annual precipitation is about 230 mm and the mean annual temperature is about 9 degrees C.

TAXONOMIC CLASS: Fine, smectitic, mesic Xeric Haplargids

TYPICAL PEDON: Milkiway clay loam--hayland. (Colors are for dry soil unless otherwise noted.)

Ap--0 to 15 cm; brown (10YR 5/3) clay loam, dark brown (10YR 3/3) moist; moderate medium angular blocky structure; very hard, firm, very sticky and very plastic; common very fine and fine roots; common very fine tubular pores; neutral (pH 6.8); clear smooth boundary. (10 to 23 cm thick)

Bt1--15 to 51 cm; pale brown (10YR 6/3) clay, brown (10YR 4/3) moist; strong medium prismatic parting to moderate medium angular blocky structure; very hard, firm, very sticky and very plastic; common very fine, fine and medium and few coarse roots; common very fine tubular pores; common pressure faces; neutral (pH 6.9); clear smooth boundary. (20 to 40 cm thick)

Bt2--51 to 76 cm; pale brown (10YR 6/3) clay, brown (10YR 4/3) moist; moderate medium prismatic parting to moderate medium angular blocky structure; very hard, firm, very sticky and very plastic; few very fine, common fine and medium roots; common very fine tubular pores; common pressure faces; neutral (pH 7.0); clear smooth boundary. (10 to 30 cm thick)

Btk1--76 to 102 cm; pale brown (10YR 6/3) clay loam, brown (10YR 4/3) moist; weak medium prismatic parting to moderate medium angular blocky structure; very hard, firm, moderately sticky and moderately plastic; few very fine, fine and medium roots; common very fine tubular pores; common distinct clay films on faces of peds and lining pores; secondary carbonates segregated as few fine masses; slightly effervescent; slightly alkaline (pH 7.8); clear smooth boundary. (10 to 30 cm thick)

Btk2--102 to 117 cm; pale brown (10YR 6/3) sandy clay loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; few very fine, common fine and medium roots; common very fine tubular pores; few distinct clay films on faces of peds and lining pores; secondary carbonates segregated as few fine masses; slightly effervescent; moderately alkaline (pH 8.3); clear wavy boundary. (13 to 25 cm thick)

Bqk--117 to 130 cm: light brownish gray (10YR 6/2) coarse sandy loam, dark grayish brown (10YR 4/2) moist; massive; hard, friable, nonsticky and nonplastic; few very fine, fine and medium roots; common very fine tubular pores; 20 percent weakly cemented planar durinodes; secondary carbonates segregated as few fine masses; slightly effervescent; moderately alkaline (pH 8.3); clear wavy boundary. (0 to 50 cm thick)

C--130 to 152 cm; light brownish gray (10YR 6/2) loamy sand, dark grayish brown (10YR 4/2) moist; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine and few fine roots; common very fine tubular and interstitial pores; common medium prominent dark yellowish brown (10YR 4/6) moist masses of iron accumulation and common coarse faint black (10YR 2/1) moist masses of manganese accumulation; slightly effervescent; moderately alkaline (pH 8.3)

TYPE LOCATION: Douglas County, Nevada; in Carson Valley about 0.25 mile west of the county airport; about 2,200 feet north and 1,700 feet east of the southwest corner of section 8, T. 13 N., R. 20 E.; USGS Genoa 7.5 minute topographic quadrangle; latitude 39 degrees 0 minutes 12.2 seconds N and longitude 119 degrees 45 minutes 51 seconds W; WGS84 Decimal Degrees 39.0034500 latitude, -119.7641667 longitude.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually dry in the moisture control section; moist in some part during winter and spring; dry in all parts summer through early fall; aridic soil moisture regime that borders on xeric.
Mean annual soil temperature: 9 to 12 degrees C.
Depth to base of argillic horizon: 64 to 127 cm.
Depth to identifiable secondary carbonates: 50 to 100 cm.

Particle-size control section - Clay content: Averages 35 to 45 percent.
Rock fragments: 0 to 5 percent, mainly gravel. Lithology of fragments is mainly igneous rocks.

A horizon
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Reaction: Neutral or slightly alkaline.

Bt horizons
Hue: 7.5YR or 10YR.
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 3 or 4, dry or moist.
Texture: Clay or clay loam.
Clay content: 35 to 50 percent.
Rock fragments: 0 to 5 percent.
Consistence: Moderately hard to very hard dry, firm moist.
Reaction: Neutral or slightly alkaline.

Btk horizons
Hue: 7.5YR or 10YR.
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 3 or 4, dry or moist.
Texture: Clay loam or sandy clay loam.
Clay content: 25 to 35 percent.
Rock fragments: 0 to 5 percent.
Consistence: Moderately hard to very hard dry, firm moist.
Reaction: Slightly alkaline or moderately alkaline.
Identifiable secondary carbonates: Occurs as few or common masses, filaments, or coats on peds.
Calcium carbonate equivalent: 1 to 3 percent.

Bqk horizon (when present)
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 2 through 4, dry or moist.
Texture: Stratified loamy coarse sand through loam, averages coarse sandy loam or sandy loam.
Clay content: 8 to 15 percent.
Rock fragments: 0 to 5 percent.
Durinodes: 20 to 80 percent 1.2 to 5 cm diameter planar durinodes.
Identifiable secondary carbonates: Occurs as few or common masses, filaments, or coats on peds.
Reaction: Slightly alkaline or moderately alkaline.
Calcium carbonate equivalent: 1 to 3 percent.

C horizon
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 3 or 4, dry or moist.
Texture: Stratified coarse sand through sandy loam, averages coarse sandy loam, sandy loam, or loamy sand.
Clay content: 5 to 12 percent.
Sand content: Greater than 45 percent.
Rock fragments: 0 to 5 percent.
Reaction: Slightly alkaline or moderately alkaline.
Redoximorphic features: Redox concentrations occurring as masses of iron and manganese accumulation are present within a depth of 100 to 150 cm in most pedons.

COMPETING SERIES: These are the Buncelvoir, Diaz, Farmell, Glasgow, Lanktree, Oppio, Risley, Schamp, and Trunk series.

Buncelvoir, Farmell, Lanktree, and Schamp soils do not have redox concentrations or endosaturation within 150 cm of the soil surface. Diaz, Glasgow, Oppio, and Trunk soils are moderately deep to lithic contacts. Risley soils are moderately deep to paralithic contacts.

GEOGRAPHIC SETTING: Milkiway soils are on stream terraces. They formed in alluvium derived from mixed rocks but with a strong influence from granitic rocks. Slopes are 0 to 2 percent. Elevations range from 1,400 to 1,465 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 250 mm, mean annual temperature is 8 to 11 degrees C, and the frost-free period is 90 to 110 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dangberg, Gardnerville, Godecke, Ormsby, and Turria soils. Dangberg soils have natric horizons and are moderately deep to duripans. Gardnerville soils have albic horizons, natric horizons, and horizons with durinodes within 100 cm of the soil surface. Godecke soils are fine-loamy and have natric horizons. Ormsby soils are sandy, have horizons with a firm and brittle matrix, and do not have argillic horizons. Turria soils are fine-loamy.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained; high surface runoff; moderately slow saturated hydraulic conductivity. Endosaturation is present with a seasonal high water table between 122 and 152 cm (deep internal free water occurrence class) from December through May. Cumulative annual duration classes are Common or Persistent.

USE AND VEGETATION: Milkiway soils are used for irrigated cropland. Common crops are alfalfa hay, small grains, and grass-legume hay.

DISTRIBUTION AND EXTENT: Western Nevada. These soils are not extensive. MLRA 26.

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

SERIES ESTABLISHED: Douglas County, Nevada, 2012.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the soil surface to 15 cm (Ap horizon).
Argillic horizon - The zone from 15 to 117 cm (Bt1, Bt2, Btk1, and Btk2 horizons).
Identifiable secondary carbonates - The zone from 76 to 130 cm (Btk1, Btk2, and Bqk horizons).
Endosaturation feature - The condition of ground water with an upper boundary between 122 and 152 cm at certain times during normal years (parts of the Bqk and C horizons).
Particle size control section - The zone from 15 to 65 cm (Bt1 horizon and part of the Bt2 horizon).

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National Cooperative Soil Survey
U.S.A.