LOCATION MERINO             CO
Established Series
Rev. TJW/LLC/TWH
12/2009

MERINO SERIES


The Merino series consists of shallow, well drained soils formed in slope alluvium derived from quartz-monzonite and other granitic rocks. Merino soils are on mountain slopes. Slope ranges from 10 to 55 percent. The mean annual precipitation is about 15 inches, and the mean annual temperature is about 38 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Lithic Haplocryepts

TYPICAL PEDON: Merino very gravelly sandy loam - on a 20 percent slope in an area of woodland at an elevation of 9,120 feet. (Colors are for dry soil unless otherwise noted.) Described on October 26, 1989.

Oe--0 to 1 inch; moderately decomposed needle litter

A--1 inch to 2 inches; grayish brown (10YR 5/2) very gravelly sandy loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, very friable, slightly sticky and slightly plastic; 45 percent gravel, 5 percent cobbles, less than 1 percent stones; neutral (pH 7.0); abrupt smooth boundary. (0 to 2 inches thick)

Bw1--2 to 6 inches; light brown (7.5YR 6/4) very gravelly sandy loam, brown (7.5YR 4/4) moist; weak very fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; 45 percent gravel; moderately acid (pH 5.8); clear wavy boundary. (3 to 10 inches thick)

Bw2--6 to 12 inches; light brown (7.5YR 6/4) extremely gravelly sandy loam, brown (7.5YR 4/4) moist; weak very fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; 70 percent gravel; moderately acid (pH 5.6); clear irregular boundary. (0 to 12 inches thick)

Cr--12 to 18 inches; moderately cemented quartz-monzonite. (0 to 8 inches thick)

R--18 inches; indurated quartz-monzonite.

TYPE LOCATION: Park County, Colorado; located about 10 miles south of Lake George, about 600 feet south and 1200 feet west of the northeast corner of Sec. 13, T. 14 S., R. 72 W. U.S.G.S. Witcher Mountain USGS quadrangle; Lat. 38 degrees, 50 minutes, 25 seconds N., and long. 105 degrees, 23 minutes, 3 seconds W. NAD 27.

RANGE IN CHARACTERISTICS:
Soil moisture: The soil moisture control section is usually moist in some part during late spring to early fall, and intermittently dry in late fall; udic moisture regime bordering ustic.

Mean annual soil temperature: 37 to 42 degrees F.
Mean summer soil temperature: 43 to 46 degrees F.
Thickness of ochric epipedon: 1 to 4 inches
Depth to cambic horizon: 2 to 6 inches
Lithology of rock fragments: quartz-monzonite or related granitic rocks
Depth to paralithic contact: 10 to 14 inches
Depth to lithic contact: 14 to 20 inches

Particle-size control section (weighted averages):
Clay content: 7 to 18 percent clay
Sand content: 40 to 80 percent
Rock fragment content: 40 to 75 percent
Mica content: 5 to 20 percent (estimated)

A horizon
Hue: 10YR or 7.5YR
Value: 5 or 6 dry; 3 or 4 moist
Chroma: 2 or 3 dry; 2 or 3 moist
Clay content: 7 to 18 percent
Rock fragment content: 40 to 59 percent
Reaction: moderately acid to neutral (pH 5.6 to 7.3)

Bw horizon(s)
Hue: 10YR or 7.5YR
Value: 5 through 7 dry; 4 through 6 moist
Chroma: 2 through 4 dry; 2 through 4 moist
Texture: very gravelly sandy loam, extremely gravelly sandy loam
Clay content: 7 to 18 percent
Rock fragment content: 35 to 80 percent
Base saturation: 50 to 75 percent (estimated)
Reaction: moderately acid or slightly acid (pH 5.6 to 6.5)

COMPETING SERIES: These are the Caseypeak, Cobblank, Cowood, Hechtman, Hotter, Jarbidge, Pendergrass, and Sigbird series.
The Caseypeak, Cowood, and Hechtman soils have an E horizon.
The Cobblank soils have a lithologic discontinuity.
The Hotter soils have a udic moisture regime that does not border ustic.
The Jarbidge soils have a xeric soil moisture regime.
The Pendergrass soils have hue redder than 7.5YR.
The Sigbird soils have shale rock fragments.

GEOGRAPHIC SETTING:
Parent material: slope alluvium derived from quartz-monzonite and other granitic rocks
Landform: mountains
Slopes: 10 to 55 percent
Elevation: 7,500 to 9,200 feet
Mean annual precipitation: 14 to 16 inches
Mean annual air temperature: 37 to 40 degrees F.
Precipitation pattern: Monthly precipitation is lowest in winter and greatest in July and August.
Frost-free period: 50 to 80 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Adderton, Lakehelen, and Rogert soils. Adderton soils are very deep, have a thick mollic epipedon, have less than 35 percent by volume rock fragments, and are on flood plains. Lakehelen soils are moderately deep and have an argillic horizon. Rogert soils have a mollic epipedon.

DRAINAGE AND PERMEABILITY: Well drained; moderately rapid permeability.

USE AND VEGETATION: These soils are used for wildlife habitat and livestock grazing. Native vegetation is an overstory of limber pine, ponderosa pine, or Rocky Mountain Douglas fir and an understory of sedges, pine dropseed, Parry's oatgrass, bluegrass, Arizona fescue, kinnikinnick, true mountain mahogany, common juniper, mountain muhly, prairie junegrass, and Oregon grape.

DISTRIBUTION AND EXTENT: Rocky Mountains of central Colorado; LRR E, MLRA 48A; small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Granite County (Philipsburg-Drummond Area), Montana, 1972. The current type location is in the Teller-Park Area, Colorado.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Series control section: The zone from 0 to 22 inches.
Particle-size control section: The zone from 1 to 12 inches. (A, Bw1,Bw2 horizons)
Ochric epipedon: The zone from 1 to 2 inches. (A horizon)
Cambic horizon: The zone from 2 to 12 inches. (Bw1, Bw2 horizons)
Paralithic contact: The contact with weathered monzonite at 12 inches. (Cr horizon)
Lithic contact: The contact with quartz-monzonite bedrock at 18 inches. (R horizon)
Cryic soil moisture regime.
Stopped here
Taxonomic Version: Classified according to the Keys of Soil Taxonomy, 10th Edition, 2006.

Colorado assumed responsibility from Montana for the series in May, 1993.

A cambic horizon was recognized in this soil and the classification changed from nonacid Lithic Cryorthents to superactive Lithic Eutrocryepts in February 1999.

The concept was narrowed to the ustic udic moisture regime. The elevation, MLRA, and the precipitation were also narrowed. AP 03/2004

The 12/2009 revision restricts this series to the soils in the Teller-Park Area only.


National Cooperative Soil Survey
U.S.A.