LOCATION MOENTO             CO

MOENTO SERIES

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Typic Argiustolls

TYPICAL PEDON: Moento loam, on a northeast facing, simple, 2 percent slope in grassland, at an elevation of 8,320 feet. (Colors are for dry soil unless otherwise noted.) Described on August 21, 1980.

A1--0 to 2 inches; dark brown (10YR 3/3) loam, very dark brown (10YR 2/2) moist; weak thin platy structure parting to weak fine granular; slightly hard, friable, nonsticky and nonplastic; common very fine and fine roots; few fine pores; slightly acid (pH 6.4); clear smooth boundary. (2 to 9 inches thick)

A2--2 to 6 inches; dark brown (10YR 3/3) clay loam, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure; hard, friable, nonsticky and nonplastic; common fine roots; few fine pores; slightly acid (pH 6.4); clear smooth boundary. (2 to 8 inches thick)

BA--6 to 12 inches; brown (10YR 4/3) clay loam, dark brown (10YR 3/3) moist; moderate medium and coarse subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common fine roots; few fine pores; slightly acid (pH 6.2); clear wavy boundary. (0 to 8 inches thick)

Bt1--12 to 21 inches; brown (7.5YR 5/4) clay loam, brown (7.5YR 4/4) moist; moderate medium and coarse subangular blocky structure; hard, firm, moderately sticky and moderately plastic; few very fine roots; few large pores; common prominent clay films on faces of peds; slightly acid (pH 6.2); gradual smooth boundary.

Bt2--21 to 30 inches; strong brown (7.5YR 5/6) sandy clay loam, strong brown (7.5YR 5/8) moist; moderate coarse subangular blocky structure; very hard, firm, slightly sticky and slightly plastic; common prominent clay films on faces of peds; few very fine roots; few very fine and fine pores; slightly acid (6.2); gradual smooth boundary. (Combined thickness of the Bt horizons is 15 to 30 inches)

C--30 to 36 inches; reddish yellow (7.5YR 6/6) sandy clay loam; reddish yellow (7.5YR 6/8) moist; massive; slightly hard, friable, nonsticky and nonplastic; slightly acid (pH 6.4); abrupt smooth boundary.

R--36 inches; sandstone bedrock that is fractured and weathered in the top 2 or 3 inches.

TYPE LOCATION: Dolores County, Colorado; about 18 miles north of Dolores; located about 2,200 feet west and 450 feet south of the northeast corner of Sec. 35, T. 40 N., R. 16 W.; Narraguinnep Mountain USGS quad; lat. 37 degrees, 41 minutes, 22 seconds N. and long. about 108 degrees, 34 minutes, 56 seconds W., NAD 27

RANGE IN CHARACTERISTICS:
Soil moisture regime: ustic; (typic ustic subclass).
Mean annual soil temperature: 43 to 47 degrees F.
Mean summer soil temperature: 59 to 64 degrees F.
Depth to lithic contact: 20 to 40 inches to fractured sandstone
Thickness of the mollic epipedon: 7 to 16 inches

Particle-size control section:
Clay content: 20 to 35 percent
Rock fragment content: 0 to 5 percent

A horizon:
Hue: 7.5YR or 10YR
Value: 3 to 5 dry, 2 or 3 moist
Chroma: 2 or 3, dry and moist
Texture: L, CL
Rock fragment content: 0 to 5 percent sandstone fragments
Reaction: slightly acid or neutral

Bt horizon:
Hue: 7.5YR or 10YR
Value: 4 to 6 dry, 3 to 5 moist
Chroma: 3 to 8, dry and moist
Texture: CL, SCL
Rock fragment content: 0 to 5 percent sandstone fragments
Reaction: slightly acid or neutral

C horizon:
Hue: 7.5YR or 10YR
Value: 5 or 6 dry and moist
Chroma: 4 to 8, dry and moist
Texture: SL, SCL
Rock fragment content: 0 to 5 percent sandstone fragments
Reaction: slightly acid or neutral

COMPETING SERIES: These are the Absarook, Beartooth, Beeno, Bielenberg, Bookcliff, Bullflat, Burtoner, Clancy, Clasoil, Dooley, Empedrado, Fairfield, Farnuf, Felor, Greenway, Gurney, Hangdo, Hyalite, Jeffcity, Lefor, Livona, Martinsdale, Maudlin, Moen, Pianohill, Placerton, Reeder, Sponseller, Trazuni, Tschicoma, Ulrant, Vida, Watrous, Wemple, Williams, and Yegen series.

Absarook: have a calcic horizon.
Beartooth, Bielenberg, Bookcliff, Bullflat, Clasoil, Empedrado, Fairfield, Farnuf, Felor, Greenway, Hangdo, Hyalite, Livona, Martinsdale, Sponseller, Trazuni, Tschicoma, Vida, Williams, and Yegen: do not have a lithic contact above a depth of 60 inches.
Beeno, Clancy, Jeffcity, Lefor, Placerton, Reeder, and Wemple: have a paralithic contact at depths of 20 to 40 inches.
Burtoner: have a paralithic contact above the lithic contact, and formed in parent material derived from granite and other coarse grained igneous rocks.
Dooley: has substratum of glacial till that has a bulk density of 1.55 or greater, and does not have bedrock above a depth of 40 inches
Gurney: has horizons of calcium carbonate accumulation below the argillic horizon.
Maudlin: is dry in all parts of the moisture control section for 45 consecutive days immediately after July 15.
Moen: formed in material derived from granite and have peak periods of precipitation in the spring and summer.
Pianohill: formed in material derived from volcanic mudflow breccia.
Ulrant: does not have a lithic contact above a depth of 40 inches.
Watrous: are calcareous in the lower part of the argillic horizon and have horizons of calcium carbonate accumulation.

GEOGRAPHIC SETTING:
Parent material: alluvium and slope alluvium derived mostly from sandstone.
Landform: mesas, hills and drainageways.
Slopes: 1 to 15 percent
Elevation: 7,800 to 8,500 feet
Mean annual air temperature: 40 to 46 degrees F.
Mean annual precipitation: 18 to 22 inches.
Wettest months: July and August receive slightly more precipitation than other months.
Driest months: May and June receive the least precipitation, however the soils are still moist from snowmelt.
Frost-free period: 75 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Detra, Jemco, and Fughes soils. All are on mesas and hills.
Detra soils have a thick mollic epipedon.
Jemco soils lack a mollic epipedon.
Fughes soils have a thick mollic epipedon and fine textured particle size control sections.

DRAINAGE AND PERMEABILITY: Well drained; low or medium runoff; moderately slow permeability.

USE AND VEGETATION: These soils are used mainly for rangeland, wildlife habitat, and recreation. Native vegetation is mainly junegrass, Arizona fescue, western wheatgrass, mountain muhly, needleandthread grass, and sedges. There are a few widely spaced ponderosa pine in some areas.

DISTRIBUTION AND EXTENT: Southwestern Colorado. LRR E, MLRA 48A. This series is of small extent.

MLRA OFFICE RESPONSIBLE: Lakewood, Colorado.

SERIES PROPOSED: Dolores County Area, Animas-Dolores Area, Colorado, 1997.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon: The zone from 0 to 12 inches. (A1, A2, and BA horizons)
Argillic horizon: The zone from 12 to 30 inches. (Bt1 and Bt2 horizons)
Lithic contact: Fractured sandstone bedrock at 30 inches.
Particle-size control section: The zone from 12 to 30 inches. (Bt1 and Bt2 horizons)

Keys to Soil Taxonomy: Classified according to the Eighth Edition, 1998

Activity class is presumed based on general trend of soils in the area.