LOCATION LAGARITA           CO
Established Series
DHC/SSP
11/1999

LAGARITA SERIES


The Lagarita series consist of very deep, well drained soils formed in alluvium and slope alluvium derived from andesite, rhyolite, breccia, or tuff. These soils are on alluvial fans and mountain footslopes. Slopes range from 2 to 40 percent. Mean annual precipitation is about 16 inches and the mean annual temperature is about 38 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Ustic Argicryolls

TYPICAL PEDON: Lagarita gravelly loam, on a southwest facing 15 percent mountain footslope on rangeland at an elevation of 9,840 feet. (colors are for dry soil unless otherwise noted)

A--0 to 9 inches; brown (7.5YR 4/2) gravelly loam, dark brown (7.5YR 3/2) moist; moderate fine and medium granular structure; slightly hard, very friable, slightly sticky and nonplastic; 15 percent gravel; slightly alkaline (pH 7.4); clear smooth boundary. (7 to 15 inches thick)

Bt--9 to 14 inches; brown (7.5YR 5/3) extremely cobbly sandy clay loam, dark brown (7.5YR 3/3) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, sticky and slightly plastic; few faint clay films on faces of peds; 35 percent gravel, 25 percent cobbles, 5 percent stones; slightly alkaline (pH 7.4); clear smooth boundary. (4 to 15 inches thick)

Bk1--14 to 19 inches; pinkish gray (7.5YR 6/2) extremely cobbly sandy clay loam, brown (7.5YR 4/3) moist; weak fine subangular blocky structure; soft, friable, sticky and slightly plastic; 30 percent gravel, 35 percent cobbles, 5 percent stones; calcium carbonates disseminated and segregated into common fine and medium seams and as coats on rock fragments; violently effervescent; moderately alkaline (pH 8.0); clear smooth boundary.

Bk2--19 to 24 inches; pinkish gray (7.5YR 7/2) very cobbly loam, brown (7.5YR 5/3) moist; weak fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; 20 percent gravel, 30 percent cobbles, 5 percent stones; calcium carbonates disseminated and segregated into common fine and medium seams and as coats on rock fragments; violently effervescent; moderately alkaline (pH 8.2); clear smooth boundary.

Bk3--24 to 35 inches; pinkish white (7.5YR 8/2) very cobbly loam, brown (7.5YR 5/3) moist; massive; soft, very friable, slightly sticky and slightly plastic; 30 percent gravel, 20 percent cobbles, 5 percent stones; calcium carbonates disseminated and segregated into many fine and medium seams and as coats on rock fragments; violently effervescent; moderately alkaline (pH 8.0); clear wavy boundary.

Bk4--35 to 45 inches; light brown (7.5YR 6/3) extremely cobbly loamy sand, brown (7.5YR 4/3) moist; single grained; loose, nonsticky and nonplastic; 55 percent gravel, 30 percent cobbles, 5 percent stones; calcium carbonates disseminated and segregated into many medium seams and as coats on rock fragments; strongly effervescent; slightly alkaline (pH 7.8); gradual wavy boundary.

Bk5--45 to 66 inches; light brown (7.5YR 6/3) extremely cobbly loamy sand, brown (7.5YR 4/3) moist; single grained; loose, nonsticky and nonplastic; 40 percent gravel, 35 percent cobbles, 5 percent stones; calcium carbonates disseminated and segregated into many medium seams and as coats on rock fragments; violently effervescent; moderately alkaline (pH 8.2). (combined thickness of the Bk horizons is 35 to 60 inches)

TYPE LOCATION: Saguache County, Colorado; about 13 miles south of Parlin, Colorado; located about 950 feet west and 2,700 feet north of the southeast corner of Section 26, T. 47 N., R. 2 E.; USGS Razor Creek Dome topographic quadrangle; latitude 38 degrees, 18 minutes, 13 seconds north and longitude 106 degrees, 43 minutes, 34 seconds west, NAD 1927.

RANGE IN CHARACTERISTICS:

Soil moisture: The soil moisture control section (smcs) is affected by precipitation that falls evenly throughout the year with the exception of a significant increase in July and August. The smcs is driest during the fall. The smcs is too dry for Udic and is considered to have an Ustic bordering on Aridic soil moisture regime.
Mean annual soil temperature: 38 to 42 degrees F.
Particle-size control section: 18 to 34 percent clay, 35 to 70 percent rock fragments
Thickness of mollic epipedon: 7 to 15 inches
Depth to top of argillic horizon: 7 to 15 inches
Depth to top of calcic horizon; 15 to 20 inches

A horizon:
Hue: 7.5YR or 10YR
Value: 3 to 5 dry, 2 or 3 moist
Chroma: 2 or 3 dry or moist
Reaction: neutral (pH 6.6) to slightly alkaline (pH 7.8)
Rock fragments: andesite, rhyolite, breccia, or tuff. 15 to 30 percent total rock fragments; 10 to 30 percent gravel, 0 to 10 percent cobbles.

Bt horizon:
Hue: 7.5YR or 10YR
Value: 4 or 5 dry, 2 to 4 moist
Chroma: 2 to 4 dry or moist
Texture: extremely cobbly sandy clay loam, extremely cobbly clay loam, very cobbly sandy clay loam, very cobbly clay loam
Reaction: neutral (pH 6.6) to slightly alkaline (pH 7.8)
Rock fragments: andesite, rhyolite, breccia, or tuff. 35 to 70 percent total rock fragments; 25 to 40 percent gravel, 15 to 40 percent cobbles, 0 to 10 percent stones.
Calcium carbonate equivalent: 0 to 10 percent.

Bk (calcic) horizons:
Hue: 7.5YR to 2.5Y
Value: 6 to 8 dry, 4 to 6 moist
Chroma: 2 to 4 dry or moist
Texture: extremely cobbly sandy clay loam, very cobbly loam, extremely cobbly loamy sand, very cobbly loamy sand
Reaction: moderately alkaline (pH 7.9) to strongly alkaline (pH 9.0)
Rock fragments: andesite, rhyolite, breccia, or tuff. 45 to 90 percent total rock fragments; 20 to 60 percent gravel, 20 to 40 percent cobbles, 0 to 10 percent stones.
Calcium carbonate equivalent: 15 to 25 percent.

COMPETING SERIES: These are the Blaine, Bowen, Fornor, Fourmile, Geertsen, Hodden, Hoodle, Libeg, Maciver, Nathale, Norriston, Parkview, Quander, Ratiopeak, Teeler, and Woodhall series.
Blaine, Bowen, Nathale, Woodhall: lithic contact between 20 and 40 inches
Fornor, Fourmile, Libeg, Norriston, Parkview, Quander, Ratiopeak: do not have calcic horizons
Geertsen: lithic contact below 40 inches
Hodden: formed from mixed sources and are drier during the winter
Hoodle: thicker argillic horizon and has weakly cemented fragments of a carbonate pan
Maciver: rock fragments are calcareous argillite
Teeler: have hue redder than 7.5YR and are more moist in the spring

GEOGRAPHIC SETTING:
Parent material: alluvium and slope alluvium from andesite, rhyolite, breccia, or tuff
Landform: alluvial fans and mountain footslopes
Slopes: 2 to 40 percent
Elevation: 9,000 to 10,100 feet
Mean annual temperature: 36 to 40 degrees F.
Mean annual precipitation: 14 to 18 inches
Frost-free period: 55 to 65 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Monchego and Quander soils. Monchego soils are on outwash fans and outwash terraces and have a strongly contrasting particle-size class. Quander soils are on the lower parts of alluvial fans and mountain footslopes and lack a calcic horizon.

DRAINAGE AND PERMEABILITY: well drained; medium to very high runoff; moderate permeability.

USE AND VEGETATION: This soil is used for rangeland. Potential native vegetation is Arizona fescue, mountain muhly, Indian ricegrass, and muttongrass. It is in the Mountain Outwash Range Site, RS 311.

DISTRIBUTION AND EXTENT: Western Colorado in LRR E and MLRA 48B. The series is of small extent.

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

SERIES ESTABLISHED: Cochetopa Soil Survey Area, Gunnison National Forest, Saguache County, Colorado, 1999. The name comes from the La Garita Mountains and the La Garita Wilderness Area.

REMARKS: Diagnostic horizons and features recognized in this pedon.

Particle-size control section: the zone from 9 to 14 inches (Bt horizon)
Mollic epipedon: the zone from 0 to 14 inches. (A and Bt horizons)
Argillic horizon: the zone from 9 to 14 inches. (Bt horizon)
Calcic horizon: the zone from 14 to 66 inches. (Bk horizons)

This soil potentially has a xeric soil moisture regime.

Taxonomic version: Eighth Edition, 1998.


National Cooperative Soil Survey
U.S.A.