LOCATION MAREMMA                 ID

Established Series
Rev. RWW/RGK/CBR
05/2018

MAREMMA SERIES

Landscape--lava fields
Landform--lava flows
Slope--0 to 12 percent
Parent material--loess-influenced alluvium
Mean annual precipitation--about 400 mm
Mean annual air temperature--about 4.4 degrees C
Depth class--very deep
Drainage class--well drained
Soil moisture regime--xeric
Soil temperature regime--frigid

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Calcic Pachic Haploxerolls

TYPICAL PEDON: Maremma sandy clay loam in an area of rangeland (Colors are for dry soil unless otherwise noted.)

A1--0 to 8 cm; dark brown (10YR 3/3) sandy clay loam, very dark brown (10YR 2/2) moist; weak coarse granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine roots; common very fine tubular pores; 2 percent gravel; slightly acid (pH 6.4); abrupt smooth boundary

A2--8 to 15 cm; dark brown (10YR 3/3) sandy clay loam, very dark brown (10YR 2/2) moist; weak thick platy structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine tubular pores; 5 percent gravel; neutral (pH 6.9); clear smooth boundary

Bt--15 to 61 cm; brown (10YR 5/3) sandy clay loam, dark brown (10YR 3/3) moist; moderate medium prismatic structure parting to weak medium subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; common very fine tubular pores; few faint clay films; 5 percent gravel; neutral (pH 6.7); abrupt wavy boundary

Bk1--61 to 76 cm; pale brown (10YR 6/3) very fine sandy loam, brown (10YR 5/3) moist; moderate coarse subangular blocky structure; hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine and few fine irregular pores; slightly effervescent (12 percent calcium carbonate equivalent); common threadlike calcium carbonate masses throughout; moderately alkaline (pH 7.9); clear wavy boundary

Bk2--76 to 119 cm; light gray (10YR 7/2) sandy clay loam, pale brown (10YR 6/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine irregular pores; violently effervescent (35 percent calcium carbonate equivalent); many lime veins and coatings on all sides of rock fragments; many threadlike calcium carbonate masses throughout and many calcium carbonate coatings on rock fragments; 10 percent gravel; moderately alkaline (pH 8.3); gradual wavy boundary

2Bk3--119 to 157 cm; light gray (10YR 7/2) extremely cobbly loam, brown (10YR 5/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; common very fine irregular pores; violently effervescent (23 percent calcium carbonate equivalent); many threadlike calcium carbonate masses throughout and many calcium carbonate coatings on rock fragments; 10 percent gravel, 30 percent cobbles, and 20 percent stones; moderately alkaline (pH 8.4)

TYPE LOCATION: Clark County, Idaho; latitude 44.28611 degrees north, longitude 112.11556 degrees west, datum WGS 84

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--4.4 to 7.2 degrees C
Thickness of mollic epipedon--50 to 76 cm
Depth to argillic horizon--10 to 28 cm
Depth to calcic horizon--64 to 89 cm

Particle-size control section (weighted averages)
Clay content--20 to 25 percent
Total rock fragment content--0 to 5 percent

A horizon
Value--3 or 4 dry, 2 or 3 moist
Chroma--2 or 3 dry or moist
Clay content--20 to 25 percent
Gravel content--0 to 5 percent
Reaction--pH 6.1 to 7.3
Thickness--10 to 28 cm

Bt horizon
Value--4 or 5 dry, 2 or 3 moist
Chroma--3 or 4 dry, 2 or 3 moist
Clay content--20 to 25 percent
Gravel content--0 to 5 percent
Reaction--pH 6.6 to 7.3
Thickness--36 to 51 cm

Bk horizon
Value--6 to 8 dry, 5 to 7 moist
Chroma--2 or 3 dry or moist
Texture (less than 2-mm fraction)--fine sandy loam, sandy loam, sandy clay loam
Clay content--15 to 25 percent
Gravel content--0 to 10 percent
Calcium carbonate equivalent--5 to 35 percent
Reaction--pH 7.9 to 8.4
Thickness--38 to 73 cm

Bk horizon
Value--6 to 8 dry, 5 to 7 moist
Chroma--2 or 3 dry or moist
Texture (less than 2-mm fraction)--loam, sandy loam
Clay content--15 to 25 percent
Total rock fragment content--60 to 85 percent
Gravel content--10 to 30 percent
Cobble content--30 to 55 percent
Stone content--0 to 20 percent
Calcium carbonate equivalent--15 to 35 percent
Reaction--pH 7.9 to 8.4
Thickness--38 to 73 cm

COMPETING SERIES:
Ricrest--no Bt horizon that has faint clay films

GEOGRAPHIC SETTING:
Elevation--1660 to 1890 m
Mean annual precipitation--300 to 525 mm
Mean annual air temperature--3.3 to 6.1 degrees C
Frost-free period--70 to 95 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well drained
Saturated hydraulic conductivity (Ksat)--1 to 50 um/sec

USE AND VEGETATION:
Major use--rangeland
Potential natural vegetation--mountain big sagebrush, bluebunch wheatgrass, Idaho fescue, arrowleaf balsamroot, thickspike wheatgrass, Letterman's needlegrass

DISTRIBUTION AND EXTENT: Small extent in east-central Idaho; MLRA 13

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Clark County, Idaho; 2018

REMARKS:
Diagnostic horizons and other features recognized in this pedon
Mollic epipedon--zone from the surface to a depth of 61 cm (A1, A2, and Bt horizons)
Calcic horizon--zone from 76 to 157 cm (Bk2 and 2Bk3 horizons)
Particle-size control section--zone from 25 to 100 cm (part of Bt horizon, Bk1 and Bk2 horizons)

Taxonomic version--Twelfth Edition, 2014

ADDITIONAL DATA:
Laboratory data--pedon number S1993ID033006; Kellogg Soil Survey Laboratory, Lincoln, NE

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National Cooperative Soil Survey
U.S.A.