LOCATION TIAGOS                  CO

Established Series
Rev. AJC/LF/KLS
09/2022

TIAGOS SERIES

The Tiagos series consists of very deep, well drained soils that formed in moderately coarse textured noncalcareous sediments derived from a variety of rock sources. These soils are on alluvial fans, glacial outwash terraces, glacial moraines, eskers, and till plains. The mean annual precipitation is about 380 mm and the mean annual air temperature is about 3 degrees C.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive Ustic Argicryolls

TYPICAL PEDON: Tiagos fine sandy loam - grassland. (Colors are for dry soil unless otherwise noted,)

A--0 to 20 cm; grayish brown (10YR 5/2) fine sandy loam, very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; soft, very friable, nonsticky, nonplastic; 5 percent gravel; neutral (pH 7.0); gradual wavy boundary. (10 to 25 cm thick)

AB--20 to 30 cm; brown (10YR 5/3) fine sandy loam, dark brown (10YR 3/3) most; weak medium subangular blocky structure that parts to fine granules; slightly hard, very friable, nonsticky, nonplastic; neutral (pH 7.0); gradual wavy boundary. (10 to 13 cm thick)

Bt--30 to 61 cm; brown (10YR 5/3) fine sandy loam, brown (10YR 4/3) moist; moderate coarse prismatic structure that parts to coarse subangular blocks; slightly hard, very friable, nonsticky, nonplastic; peds are hard, friable; wax-like patches on faces of peds; waxlike bridges between sand grains; some glossy coatings in root channels and pores; wax-like coatings on the bottom of rock fragments; 5 percent gravel; neutral (pH 7.2); gradual wavy boundary. (13 to 76 cm thick)

BC--61 to 71 cm; brown (10YR 5/3) fine sandy loam, brown (10YR 4/3) moist; weak coarse subangular blocky structure; slightly hard, very friable, nonsticky, nonplastic; peds are hard, very friable; 5 percent gravel; neutral (pH 7.2); diffuse wavy boundary. (8 to 13 cm thick)

C--71 to 152 cm; pale brown (10YR 6/3) fine sandy loam, brown (10YR 4/3) moist; massive; slightly hard, very friable, nonsticky, nonplastic; 10 percent gravel; noncalcareous; neutral (pH 7.2).

TYPE LOCATION: Jackson County, Colorado; near NE corner Sec. 12, T. 10 N., R. 80 W.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature--6 degrees C
Mean summer soil temperature--13 degrees C
Depth to calcareous material--100 to more than 150 cm
Depth to base of argillic horizon--40 to 125 cm
Exchangeable sodium percentage--0 to 15 percent
Rock fragment content--0 to 35 percent by volume above 125 cm; fragments are mainly 10 to 250 mm in diameter

A horizon
Hue--5Y through 7.5YR
Value--4 or 5 dry, 2 or 3 moist
Chroma--1 through 3
Reaction--pH 6.6 to 7.6

Bt horizon
Hue--5Y through 7.5YR
Value--5 through 7 dry, 4 through 6 moist
Chroma--1 through 6
Texture--sandy loam, fine sandy loam
Clay content--8 to 18 percent clay
Sand content--50 to 80 percent with more than 35 percent fine sand or coarser
Reaction--pH 6.6 to 7.6

C horizon
Hue--5Y through 7.5YR
Texture--sandy loam, fine sandy loam
Clay content--5 to 18 percent
Sand content--50 to 80 percent with more than 35 percent fine sand or coarser
Reaction--pH 6.6 to 7.6

COMPETING SERIES: These are the Bassel, Boulder, Burgess, Ethelman, Greenhalgh, and Scriver series. Basgel soils have continuous horizons of secondary carbonate accumulation and are calcareous above a depth of 100 cm. Boulder soils have noncontrasting sandy-skeletal substratums above a depth of 100 cm and have more than 15 percent rock fragments throughout the solum. Burgess and Greenhalgh soils have a lithic contact above a depth of 100 cm. Ethelman soils have a paralithic contact above a depth of 100 cm. Scriver soils are mainly slightly and moderately acid and have a Bt horizon in which silicate clay is accumulating as lamellae.

GEOGRAPHIC SETTING:
Landform--alluvial fans, glacial outwash terraces, glacial moraines, eskers, and till plains
Elevation--2450 to 2750 meters
Slope--2 to 30 percent
Parent material--alluvium and glacial till sediments derived from a variety of rock sources
Mean annual precipitation--350 to 400 mm, with peak periods of precipitation during the spring and early summer
Mean annual air temperature--2 to 4 degrees C
Mean summer temperature--13 degrees C
Frost-free period--30 to 40 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed

DRAINAGE AND PERMEABILITY: Well drained; moderately rapid permeability.

USE AND VEGETATION: These soils are used principally as native pastureland. Native vegetation is big sage, bluebunch wheatgrass, pine needlegrass, and sheep fescue.

DISTRIBUTION AND EXTENT: Tiagos soils are moderately extensive in the high mountain valleys of north-central Colorado; MLRA 48B

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Jackson County, Colorado, 1973

REMARKS: Converted to metric, updated formatting, and O horizons were updated to start at zero. Competing series section was not updated. 7/2022

Tiagos soils have a cryic temperature regime and an ustic soil moisture regime.

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National Cooperative Soil Survey
U.S.A.