LOCATION GULNARE COEstablished Series
TAXONOMIC CLASS: Loamy, mixed, superactive, frigid Lithic Haplustalfs
TYPICAL PEDON: Gulnare loam - open stand of ponderosa pine. (Colors are for dry soil unless otherwise stated.)
Oi--0 inches to 2; partially decomposed pine needles.
E--2 to 5 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; very friable, nonsticky and nonplastic; 5 percent cobbles, 2 percent stones; neutral (pH 6.8); abrupt smooth boundary. (2 to 4 inches thick)
Bt1--5 to 13 inches; brown (7.5YR 5/4) gravelly clay loam, brown (7.5YR 4/4) moist; moderate medium subangular blocky structure parting to moderate fine subangular blocky; hard, firm, sticky and plastic; 45 distinct clay films on all faces of peds; 15 percent gravel; neutral (pH 7.0); clear smooth boundary. (6 to 9 inches thick)
Bt2--13 to 17 inches; strong brown (7.5YR 5/6) gravelly sandy clay loam, strong brown (7.5YR 4/6) moist; moderate medium subangular blocky structure; hard, firm, sticky and plastic; 40 percent distinct clay films on all faces of peds; 15 percent gravel; moderately acid (pH 5.6); abrupt wavy boundary. (2 to 6 inches thick)
Cr--17 to 19 inches; decomposed sandstone. (0 to 3 inches thick).
R--19 inches; sandstone.
TYPE LOCATION: Las Animas County, Colorado; about 1 mile south of McDonald Reservoir and 1/2 mile west of the Sarcillo Canyon Road; 2,500 feet south and 800 feet west of the northeast corner of Sec. 1, T. 33 S., R. 67 W.; Latitude 37 degrees, 12 minutes 4 seconds N., longitude 104 degrees, 49 minutes 58 seconds W.
RANGE IN CHARACTERISTICS: (Depths are given from the mineral soil surface)
Soil moisture: intermittently moist in some part April through August.
Soil moisture regime: typic ustic moisture regime.
Mean annual soil temperature ranges from 44 to 46 degrees F.
Mean summer soil temperature ranges from 57 to 60 degrees F.
Depth to lithic contact: 10 to 20 inches.
Thickness of the argillic horizon: 8 to 12 inches.
Particle size control section: (weighted average)
Clay content: 20 to 35 percent
Sand content: 35 to 50 percent
Rock fragment content: 15 to 35 percent
In some pedons an A horizon is present.
The E horizon:
Hue: 7.5YR to 2.5Y
Value: 5 to 7 dry, 3 to 5 moist
Chroma: 2 through 4.
Rock fragment content: 0 to 15 percent
Reaction: slightly acid or neutral
The Bt horizons:
Hue: 7.5YR to 2.5Y
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 4 through 6
Texture: gravelly clay loam, gravelly sandy clay loam
Clay content: 20 to 35 percent.
Sand content: 35 to 50 percent
Rock fragment content: 15 to 35 percent
Reaction: moderately acid to neutral
COMPETING SERIES: These are the
Benlowe(CO),
Joebas(CO), and
Lajuita(NM) series.
Benlowe and Lajuita soils are dry in the moisture control section at some time during
May and June.
Joebas soils have hues 5YR or redder.
GEOGRAPHIC SETTING:
Parent material: Colluvium and residuum from sandstone, commonly the Poison Canyon Formation.
Landform: Hills, ridges, and mountain slopes.
Slopes range from 5 to 50 percent.
The mean annual air temperature ranges from 42 to 46 degrees F.
The mean annual precipitation ranges from 17 to 23 inches with peak periods in spring and summer months.
Elevation ranges from 6,800 to 9,000 feet.
The frost-free period is 80 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Allens Park,
Trujillo, and
Wahatoya soils. Allens Park soils have bedrock between 20 to 40 inches and are on summits and footslopes of hills.
Trujillo soils are very deep, have a mollic epipedon, and are on footslopes and toeslopes of hills.
Wahatoya soils have greater than 35 percent rock fragments in the control section and are on backslopes of hills.
DRAINAGE AND PERMEABILITY: Well drained; rapid to very rapid runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used for livestock grazing, Woodland, recreation, and wildlife habitat. Principal native vegetation is ponderosa pine with an understory of Arizona fescue, Mountain muhly, Parry oatgrass, pine dropseed, and mountain brome.
DISTRIBUTION AND EXTENT: Southeastern Colorado. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Las Animas County, Colorado, 2007. The name is from a small town in the foothills of Las Animas County
REMARKS: Diagnostic horizons and features recognized in this pedon:
Argillic horizon: the zone from 5 to 18 inches (Bt1 and Bt2 horizons).
Lithic contact: the contact with sandstone at 20 inches.
Last updated by the state 11/2001.
Taxonomic Version: Eighth Edition, 1998