LOCATION QUANDER            CO+WY

QUANDER SERIES

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

TYPICAL PEDON: Quander loam, on a northeast facing, 7 percent slope, in rangeland at an elevation of 10,440 feet. (colors are for dry soil unless otherwise noted)

A--0 to 8 inches; brown (7.5YR 5/3) loam, dark brown (7.5YR 3/3) moist; moderate fine granular structure; soft, very friable, moderately sticky and nonplastic; 3 percent gravel, 2 percent cobbles, 1 percent flagstones; slightly acid (pH 6.4); clear wavy boundary. (6 to 15 inches thick)

ABt--8 to 11 inches; brown (7.5YR 4/2) very gravelly loam, dark brown (7.5YR 3/2) moist; weak medium subangular blocky structure; slightly hard, firm, moderately sticky and slightly plastic; few faint clay films on faces of peds and as bridges; 40 percent gravel, 5 percent flagstones; neutral (pH 6.6); clear wavy boundary. (0 to 9 inches thick)

Bt1--11 to 18 inches; light brown (7.5YR 6/4) extremely gravelly clay loam, brown (7.5YR 5/4) moist; weak medium subangular blocky structure; hard, very firm, moderately sticky and slightly plastic; common faint clay films on faces of peds and as bridges; 60 percent gravel, 10 percent flagstones; neutral (pH 6.6); clear wavy boundary.

Bt2--18 to 34 inches; pink (7.5YR 7/4) extremely gravelly clay loam, brown (7.5YR 5/4) moist; moderate medium subangular blocky structure; very hard, very firm, moderately sticky and slightly plastic; many distinct clay films on faces of peds; 60 percent gravel, 10 percent flagstones; slightly acid (pH 6.4); abrupt wavy boundary. (combined thickness of the Bt horizons is 20 to 35 inches)

BC--34 to 66 inches; reddish yellow (7.5YR 6/6) extremely gravelly clay loam, strong brown (7.5YR 4/6) moist; weak fine and medium subangular blocky structure; hard, firm, moderately sticky and slightly plastic; 65 percent gravel, 15 percent flagstones; slightly acid (pH 6.4). (11 to 38 inches thick)

TYPE LOCATION: Saguache County, Colorado; about 33 miles south of Gunnison, Colorado; within an unsectionized area of Gunnison National Forest, estimated to be in Section 11, T. 44 N., R. 1 E.; USGS Elk Park topographic quadrangle; latitude 38 degrees, 04 minutes, 49 seconds north and longitude 106 degrees, 49 minutes, 40 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 soil moisture regime.
Mean annual soil temperature: 36 to 44 degrees F.
Thickness of mollic epipedon: 10 to 15 inches
Depth to argillic horizon; 10 to 15 inches
Particle-size control section: 24 to 34 percent clay, 35 to 85 percent rock fragments.

A horizons:
Hue: 7.5YR or 10YR
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 1 to 3 dry or moist
Reaction: slightly acid (pH 6.1) to neutral (pH 7.3)
Rock fragments: trachyte, andesite, rhyolite, breccia, or tuff. 5 to 55 percent total rock fragments.

ABt horizons (when present):
Hue: 7.5YR or 10YR
Value: 4 or 5 dry, 2 or 3 moist
Chroma: 1 to 3 dry or moist
Texture: loam modified by rock fragments
Reaction: slightly acid (pH 6.1) to neutral (pH 7.3)
Rock fragments: trachyte, andesite, rhyolite, breccia, or tuff. 5 to 50 percent total rock fragments.

Bt horizons:
Hue: 5YR to 10YR
Value: 5 to 7 dry, 4 or 5 moist
Chroma: 2 to 4 dry or moist
Texture: sandy clay loam, clay, clay loam modified by rock fragments
Reaction: slightly acid (pH 6.1) to neutral (pH 7.3)
Rock fragments: trachyte, andesite, rhyolite, breccia, or tuff. 35 to 75 percent total rock fragments.

BC or C horizons:
Hue: 7.5YR or 10YR
Value: 5 to 7 dry, 4 through 6 moist
Chroma: 2 through 6 dry or moist
Texture: clay loam, loam, sandy loam, or sandy clay loam modified by rock fragments
Reaction: slightly acid (pH 6.1) to slightly alkaline (pH 7.8)
Rock fragments: andesite, rhyolite, breccia, trachyte, or tuff. 35 to 85 percent total rock fragments.

COMPETING SERIES:
Blaine, Bowen, Nathale, Nathrop, Woodhall: lithic contact at depths of less than 40 inches
Fourmile : do not have lithologic discontinuity with sandy-skeletal materials
Fornor, Hodden, Hoodle, Hoodling, Lagarita, Maciver, Ratiopeak, Teeler: have secondary accumulations of calcium carbonate
Geertsen: lithic contact between 40 and 60 inches
Libeg: have less than 20 percent clay in the BC or C horizons
Norriston: less than 20 percent clay in the particle-size control section
Parkview: paralithic contact between 20 and 40 inches
Spanpeak: has O horizon and is forested

GEOGRAPHIC SETTING:
Parent material: slope alluvium and colluvium derived from trachyte, andesite, rhyolite, breccia, or tuff
Landform: toeslopes, footslopes, and backslopes of ridges and mountains
Slopes: 5 to 65 percent
Elevation: 8,400 to 11,200 feet
Mean annual temperature: 37 to 42 degrees F.
Mean annual precipitation: 15 to 25 inches
Frost-free period: 50 to 80 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bushpark, Seitz, and Tellura soils. Bushpark soils are on shoulders and backslopes and have a lithic contact at less than 20 inches. Seitz soils are on backslopes and have more than 35 percent clay in the particle-size control section. Tellura soils are on backslopes and toeslopes and have more than 35 percent clay in the particle-size control section.

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

USE AND VEGETATION: This soil is used for rangeland. Potential native vegetation is mountain muhly, prairie junegrass, blue grama, slimstem muhly, Thurber fescue, Parry oatgrass, Arizona fescue, and big bluegrass. It is in the Subalpine Loam Range Site, RS 250, or Skeletal Loam 377 Range Site.

DISTRIBUTION AND EXTENT: Southwest Colorado in LRR E and MLRA 48A. The series is of moderate extent.

MLRA OFFICE RESPONSIBLE: Lakewood, Colorado

SERIES ESTABLISHED: Summit County, Colorado, 1974.

REMARKS: Diagnostic horizons and features recognized in this pedon.
Particle-size control section: the zone from 11 to 31 inches. (Bt horizons)
Mollic epipedon: the zone from 0 to 11 inches. (A horizons)
Argillic horizon: the zone from 11 to 34 inches. (Bt horizons)

The central concept of parent material, landforms, and soil moisture regime for the Quander series was narrowed November 1999. The type location was moved to the Cochetopa SSA in Saguache County, Colorado to better reflect the current concept All pedons previously correlated to the Quander series will need to be reevaluated for compatibility with the revised Quander series.

Taxonomic version: 9th Edition, 2003.