LOCATION MINE                    CO+WY

Established Series
Rev. AJC-KLS
03/2023

MINE SERIES

The Mine series consists of very deep, well drained soils that formed in slope alluvium and/or colluvium weathered from gneiss, schist, and quartizite. Mine soils are on outwash plains, alluvial fans, and valley side slopes and have slopes of 2 to 20 percent. The mean annual precipitation is about 810 mm, and the mean annual air temperature is about -1 degrees C.

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

TYPICAL PEDON: Mine loam - forest. (Colors are for dry soil unless otherwise noted.)

Oi--0 to 3 cm; undecomposed organic material mainly needles, bark, and twigs.

A--3 to 11 cm; dark grayish brown (10YR 4/2) loam, very dark brown (10YR 2/2) moist; strong medium crumb structure; soft, very friable, nonsticky, nonplastic; 5 percent gravel; slightly acid (pH 6.1); gradual wavy boundary. (3 to 10 cm thick)

AC--11 to 19 cm; grayish brown (10YR 5/2) gravelly loam, dark grayish brown (10YR 4/2) moist; weak medium subangular blocky structure that parts to fine granules; soft, very friable, nonsticky, nonplastic; 5 percent gravel; moderately acid (pH 5.8); gradual wavy boundary. (0 to 13 cm thick)

C--19 to 156 cm; light yellowish brown (2.5Y 6/3) gravelly sandy loam, light olive brown (2.5Y 5/3) moist; massive; soft, very friable, nonsticky, nonplastic; 5 percent gravel; moderately acid (pH 5.8).

TYPE LOCATION: Grand County, Colorado; about 15 meters west of the road and 160 meters north of Forest Service headquarters; in NE , NE , sec. 4, T. 2 S., R. 76 W.

RANGE IN CHARACTERISTICS:
These soils are dry in some part of the moisture control section in some time most years.
Depth to uniformly calcareous material--100 to 150 cm or more
Base saturation--more than 60 percent

Particle-size control section:
Texture--sandy loam or gravelly sand loam
Clay content--5 to 18 percent
Sand content--50 to 80 percent with more than 35 percent being fine or coarser sand
Rock fragment content--0 to 35 percent, mainly 10 to 250 mm in diameter
Although pH of some subhorizons is less than 5.5, a major part of the control section between depths of 25 to 50 cm has pH exceeding 5.5.
Some pedons have subhorizons redder than 7.5YR, but a major part of the control section above a depth of 100 cm has hue of 7.5YR or yellower.

A horizon
Hue--5Y through 7.5YR
Value--4 through 6 dry, 2 through 4 moist
Chroma--1 through 4
Reaction--pH 5.1 to 6.5

C horizon
Hue--5Y through 7.5YR
Some pedons contain subhorizons redder than 7.5YR.
Reaction--pH 5.1 to 6.5

COMPETING SERIES: These are the Baldy, Bobtail, and Stecum series. Baldy soils have a significant component of volcanic ash and have peak periods of precipitation in the late summer and winter months. Bobtail soils have an albic horizon and a cambic horizon. Stecum soils are sandy-skeletal.

GEOGRAPHIC SETTING:
Landform--gently to steeply sloping outwash plains, alluvial fans, and valley side slopes
Elevation--2275 to 2900 meters
Slope--2 to 20 percent or more
Parent material--thick moderately coarse textured noncalcareous transported material derived principally from gneiss, schist, and quartizite
Mean annual precipitation--810 mm, with peak periods of precipitation in the spring and early summer months
Mean annual air temperature--minus 1 degrees C
Mean summer air temperature--11 degrees C
Frost-free period--70 to 80 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed.

DRAINAGE AND PERMEABILITY: Well drained; slow to very slow runoff; rapid to very rapid permeability.

USE AND VEGETATION: Used principally as grazing land or for timber production. Native vegetation is lodgepole pine, fir, spruce, and aspen with a weak understory of grasses and shrubs.

DISTRIBUTION AND EXTENT: Mine soils are of small extent in central Colorado and western Wyoming; MLRAs 43B and 48A.

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

SERIES ESTABLISHED: Frazer Alpine Area, Colorado, 1957

REMARKS: The differentiation between the Baldy and Mine series needs further investigation.

Mine soils have a cryic temperature regime and a udic soil moisture regime.

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

---

National Cooperative Soil Survey
U.S.A.