LOCATION MILLICH CAEstablished Series
TAXONOMIC CLASS: Clayey, smectitic, frigid Lithic Argixerolls
TYPICAL PEDON: Millich very stony loam--rangeland. (Colors are for dry soil unless otherwise noted.)
A--0 to 8 cm; grayish brown (10YR 5/2) very stony loam, dark brown (10YR 3/3) moist; moderate thin platy structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and medium roots; common very fine vesicular pores; 15 percent gravel, 10 percent cobbles, and 10 percent stones neutral (pH 7.0); abrupt wavy boundary. (3 to 8 cm thick)
Bt1--8 to 20 cm; dark grayish brown (10YR 4/2) cobbly clay loam, dark brown (10YR 3/3) moist; moderate fine subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common fine and medium roots; common very fine and fine interstitial and tubular pores; many faint clay films lining pores and and on faces of peds; 15 percent gravel and 10 percent cobbles; slightly acid (pH 6.2); abrupt wavy boundary. (8 to 15 cm thick)
Bt2--20 to 30 cm; grayish brown (10YR 5/2) clay, brown (10YR 4/3) moist; strong medium prismatic structure parting to strong medium and coarse subangular blocky stucture; extremely hard, extremely firm, very sticky and very plastic; common very fine exped roots; few very fine and fine tubular pores; continuous distinct clay films lining pores and common distinct clay films on faces of peds; 5 percent gravel and 5 percent cobbles; slightly acid (pH 6.3); abrupt wavy boundary. (10 to 23 cm thick)
Bt3--30 to 43 cm; grayish brown (10YR 5/2) clay, brown (10YR 4/3) moist; strong fine and medium angular blocky structure; extremely hard, extremely firm, very sticky and very plastic; common very fine exped roots; few very fine and fine tubular pores; continuous distinct clay films on faces of peds and lining pores; few cobbles and stones; slightly acid (pH 6.3); abrupt wavy boundary. (0 to 18 cm thick)
R--43 cm; gray (N 6/) vesicular andesitic bedrock, very hard, but slightly weathered; some clay films in fracture planes.
TYPE LOCATION: Plumas County, California; about 2 miles south of Vinton; about 500 feet west and 2000 feet south of the northeast corner of section 9, T. 22 N., R. 16 E.; latitude 39 degrees 46 minutes 30 seconds N and longitude 120 degrees 11 minutes 08 seconds W;, NAD 83.
RANGE IN CHARACTERISTICS:
Soil moisture - Usually dry, moist in winter and early spring; xeric moisture regime that borders on aridic.
Mean annual soil temperature: 7 to 8 degrees C.
Mean summer temperature: 16 to 18 degrees C.
Mollic epipedon thickness: 18 to 25 cm; includes the Bt1 horizon and also the Bt2 horizon in some pedons.
Depth to bedrock: 25 to 50 cm to a lithic contact.
Particle-size control section - Clay content: Averages 35 to 50 percent.
Rock fragments: Averages 5 to 15 percent, mainly cobbles. Lithology of fragments are volcanic rocks such as andesite, andesitic tuff, or andesitic tuff-breccia.
A horizon
Hue: 10YR or 7.5YR.
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Organic matter content: 1 or 2 percent.
Bt1 horizon
Hue: 10YR or 7.5YR.
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Texture: Cobbly clay loam or stony clay loam.
Clay content: 27 to 35 percent.
Rock fragments: 5 to 15 percent.
Organic matter content: 1 or 2 percent.
Reaction: Moderately acid or slightly acid.
Bt2 horizon and Bt3 horizon (when present)
Hue: 10YR or 7.5YR.
Value: 4 or 5 dry, 3 or 4 moist.
Chroma: 2 through 4, dry or moist.
Texture: Clay or clay loam.
Clay content: 35 to 50 percent.
Rock fragments: 5 to 10 percent.
Structure: Prismatic or angular blocky.
Organic matter content: 1 or 2 percent.
COMPETING SERIES: These are the Alding, Crocan, Madeline, Merlin, and Ninemile series.
Alding soils have surface horizons that are influenced by volcanic ash. Crocan, Madeline and Ninemile soils have aridic soil moisture regimes. Merlin soils have more than 60 percent clay in the argillic horizon.
GEOGRAPHIC SETTING: Millich soils are on hills. They formed in residuum and colluvium derived from volcanic rocks such as andesite, andesitic tuff, and tuff-breccia. Slopes are 5 to 60 percent. Elevations range from 1,650 to 1,985 meters. The climate is subhumid with cold, moist winters and warm, dry summers. The mean annual precipitation is 300 to 460 mm. The mean annual temperature is 7 to 9 degrees C. The frost-free period is 60 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aldax and Bieber soils. Aldax soils lack argillic horizons. Bieber soils have a duripan within 50 cm of the soil surface.
DRAINAGE AND PERMEABILITY: Well drained; very high surface runoff; slow permeability; moderately low saturated hydraulic conductivity.
USE AND VEGETATION: Millich soils are used for livestock grazing. The vegetation is antelope bitterbrush, low sagebrush, mountain big sagebrush, needlegrass, bottlebrush squirreltail, singleleaf pinyon, and widely spaced Jeffrey pine.
DISTRIBUTION AND EXTENT: Northeastern California. These soils are not extensive with about 2,000 acres of the series mapped to date. The series concept is in MLRA 26, while other acreage occurs in MLRA 21.
MLRA OFFICE RESPONSIBLE: Reno, Nevada.
SERIES ESTABLISHED: Alpine County (Carson Valley Area), California, 1973.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 18 cm (A and Bt1 horizons and part of the Bt2 horizon).
Argillic horizon - The zone from 8 to 43 cm (Bt1, Bt2, and Bt3 horizons).
Lithic contact - The boundary at 43 cm to underlying hard, unweathered bedrock (R layer).
Particle-size control section - The zone from 8 to 43 cm (Bt1, Bt2, and Bt3 horizons).
ADDITIONAL DATA: previuos authors and editors include: LNL-GMK-LCL-JVC. The type location was moved 10/2009 to the Sierra Valley area to better reflect the series concept.