LOCATION ROSANE                  CO+WY

Established Series
Rev. GB-KLS
03/2023

ROSANE SERIES

The soils of the Rosane series consists of deep, poorly drained soils formed in mixed alluvium. They are in concave positions on flood plains, terraces or low alluvial fans and have slopes of 0 to 6 percent. The mean annual precipitation is about 310 mm and the mean annual air temperature is about 13 degrees C.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive Typic Cryaquolls

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

Oi--0 to 3 cm; undecomposed and partially decomposed organic material, mostly from rushes, sedges, and water-tolerant grasses. (0 to 8 cm thick).

Ag1--3 to 23 cm; grayish brown (10YR 5/2) fine sandy loam, very dark grayish brown (10YR 3/2) moist; common, fine, distinct, strong brown (7.5YR 5/6) moist mottles; moderate, granular structure; soft, very friable; neutral; gradual, wavy boundary. (15 to 25 cm thick)

Ag2--23 to 43 cm; gray (2.5Y 5/1) fine sandy loam, very dark gray (2.5Y 3/1) moist; many, large, prominent, strong brown (7.5YR 5/6) moist mottles; weak, medium, subangular blocky structure parting to moderate, fine, granular structure; soft, very friable; neutral; gradual wavy boundary. (10 to 23 cm thick)

Bg--43 to 73 cm; gray (5Y 6/1) fine sandy loam, dark gray (5Y 4/1) moist; many, large, prominent, strong brown (7.5YR 5/6) moist mottles; massive; soft, very friable; 5 percent pebbles; neutral; clear wavy boundary. (0 to 53 cm thick)

2Cg--73 to 154 cm; sand and gravel; many large prominent bright colored mottles.

TYPE LOCATION: Lake County, Colorado; about 75 meters east and 60 meters south of the northwest corner of sec. 3, T. 8 E., R. 49 S.

RANGE IN CHARACTERISTICS:
Mollic epipedon thickness--18 to 50 cm
Solum thickness--38 to 100 cm
Depth to contrasting sand and gravel substratum--60 to 100 cm
Base saturation--80 to 100 percent

Typically, these soils are noncalcareous to depths of more than 150 cm and are noncalcareous in excess of 100 cm in all pedons.
These soils have fluctuating water tables that rise to near the ground surface many times during most years.

Particle-size control section:
Rock fragment content--0 to 15 percent in the upper part
Rock fragment content--35 to 70 percent in the lower part
Reaction--pH 6.6 to 7.8

A horizons
Hue--5Y through 10YR
Value--4 or 5, 2 or 3 moist
Chroma--1 through 3.
Structure--granular or crumb structure, but it has weak subangular blocky structure in some pedons
This horizon is typically strongly mottled in the lower part.

Bg horizon
Hue--5Y or 2.5Y
Value--5 or 6, 4 or 5 moist
Chroma--0 through 2
Structure--subangular blocky structure and parts to granular or crumb, but is massive in some pedons
Texture--fine sandy loam
Clay content--8 to 18 percent

2Cg horizon
Typically, this horizon is not calcareous, but may be weakly calcareous below 100 cm in some pedons.

COMPETING SERIES: This is the Fourlog (T) series. Fourlog soils lack sand and gravel within the particle-size control section.

GEOGRAPHIC SETTING:
Landform--depressional or concave portions of floodplains, terraces, or low alluvial fans
Elevation--2200 to 3200 meters
Slope--0 to 6 percent
Parent material--uniformly mixed alluvium
Mean annual precipitation--310 mm with a peak during the months of April through September
Mean annual air temperature--2 degrees C
Mean summer air temperature--11 degrees C
Frost-free period--55 to 95 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed.

DRAINAGE AND PERMEABILITY: Poorly drained; slow runoff; moderately rapid to rapid permeability but soil has a high water table.

USE AND VEGETATION: These soils are used principally as native pastureland. Native hay crops may be harvested in some years. Native vegetation is mainly water-tolerant grasses, sedges, rushes, and willows.

DISTRIBUTION AND EXTENT: Rosane soils are of small extent in the high mountain valleys of central Colorado; MLRA 48A.

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

SERIES ESTABLISHED: Lake County, Colorado, 1974.

REMARKS: Rosane soils have a cryic temperature regime and an aquic soil moisture regime.

Converted to metric and O horizons were updated to start at zero. Competing series section was not updated. 02/2023

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National Cooperative Soil Survey
U.S.A.