LOCATION FISHERS COEstablished Series
TAXONOMIC CLASS: Clayey-skeletal, smectitic, frigid Typic Haplustalfs
TYPICAL PEDON: Fishers very cobbly loam - Basalt mesa side slopes. (Colors are for dry soil unless otherwise noted).
Oe--0 to 1 inches; partially decomposed oak and locust leaves.
A1--1 to 5 inches; very dark gray (10YR 3/1) very cobbly loam, black (10YR 2/1) moist; strong fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; 25 percent gravel, 15 percent cobbles; slightly acid (pH 6.4); clear smooth boundary.
A2--5 to 9 inches; dark gray (10YR 4/1) very cobbly loam, very dark gray (10YR 3/1) moist; strong very fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; 25 percent gravel, 15 percent cobbles; neutral (pH 6.6); clear wavy boundary. (Combined thickness of the A1 and A2 horizons is 6 to 9 inches)
E--9 to 14 inches; pale brown (10YR 6/3) very cobbly loam, brown (10YR 4/3) moist and crushed; weak medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; 30 percent gravel, 20 percent cobbles; slightly acid (pH 6.2); abrupt wavy boundary. (5 to 8 inches)
Bt1--14 to 19 inches; brown (7.5YR 5/3) very gravelly clay loam, brown (7.5YR 4/3) moist; moderate fine subangular blocky structure; very hard, firm, sticky and plastic; few faint clay films on faces of peds; 30 percent gravel, 15 percent cobbles; slightly acid (pH 6.4) clear smooth boundary.
Bt2--19 to 36 inches; brown (7.5YR 5/2) very gravelly clay, brown (7.5YR 4/2) moist and crushed; moderate medium and coarse subangular blocky structure; extremely hard, very firm, sticky and plastic; common distinct clay films on faces of peds; 30 percent gravel, 15 percent cobbles; slightly acid (pH 6.4); clear wavy boundary.
Bt3--36 to 47 inches; brown (10YR 5/3) very gravelly clay loam, brown (10YR 4/3) moist; moderate medium and coarse subangular blocky structure; extremely hard, very firm, sticky and plastic; few faint clay films on faces of peds; 30 percent gravel, 10 percent cobbles; neutral (pH 6.6); clear wavy boundary. (The combined thickness of the Bt horizons is 30 to 45 inches)
C--47 to 64 inches; light yellowish brown (10YR 6/4) very cobbly clay loam, yellowish brown (10YR 5/4) moist; weak medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; few faint oriented clay films in pores; 25 percent gravel, 25 percent cobbles; neutral (pH 6.6).
TYPE LOCATION: Las Animas County, Colorado; on an old trail about 200 feet north of Cassidays Spring in an unsectionalized area about 3.2 miles east of exit 8 on I-25 approaching Raton Pass; T. 34 S., R. 63 W.; Fishers Peak USGS quad; Lat. 37 degrees 04 minutes 49 seconds N. and Long. 104 degrees 27 minutes 40 seconds W.
RANGE IN CHARACTERISTICS:
Soil moisture: moist in some part April through September, driest December through February. Ustic moisture regime .
Mean annual soil temperature ranges from 42 to 45 degrees F.
Mean summer soil temperature: 61 to 63 degrees F.
Thickness of the mollic epipedon: 6 to 9 inches.
Depth to the base of the argillic: 40 to 60 inches or more.
Particle size control section:
Clay content: 35 to 50 percent
Rock fragment content: 35 to 70 percent, and are dominantly gravel and cobbles.
A horizons:
Hue: 10YR or 7.5YR
Value: 3 or 4 dry, 2 or 3 moist
Chroma: 1 through 3
Rock fragment content: 25 to 50 percent
Reaction is neutral or slightly acid.
E horizon:
Hue: 10YR or 7.5YR
Value: 5 through 7 dry, 3 through 6 moist
Chroma: 2 or 3
Rock fragment content: 25 to 50 percent
Textures of the fine earth fraction: loam, silt loam, and fine sandy loam
Reaction ranges from moderately acid to neutral.
Bt horizons:
Hue: 5YR through 10YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2 through 4
Rock fragment content: 35 to 70 percent
Textures of the fine earth fraction: clay loam or clay
Clay content: 35 to 50 percent
Reaction is slightly acid to neutral.
C horizon: (BC in some pedons)
Hue of 7.5YR or 10YR
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 2 to 4
Rock fragment content: 35 to 70 percent
Textures of the fine earth fraction: clay loam and sandy clay loam with the sand content increasing with depth. Some pedons may have sandy loam textures.
COMPETING SERIES: These are the
Pinacol(CO),
Pleioville(NM), and
Ring(NM) series.
Pinacol soils: are dry in
May and June and average less than 25 percent rock fragments in the A and E horizons.
Pleioville soils: have a lithic contact at depths of 20 to 40 inches.
Ring soils: average 45 to 60 percent sand in the control section and formed on outwash terraces.
GEOGRAPHIC SETTING:
Landform: side slopes of basalt capped mesas, mountain slopes and lava plateaus.
Parent material: colluvium derived from basalt.
Elevation: 7,800 to 9,000 feet.
Mean annual temperature ranges from 42 to 44 degrees F.
Mean annual precipitation ranges from 18 to 22 inches
Wettest period: April to August
Driest period: December through February
Frost-free period: 60 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Bandarito and
Fuera soils.
Bandarito soils: have a mollic epipedon greater than 9 inches thick and average less than 35 percent rock fragments in the control section. They are in open grassy meadows.
Fuera soils: average less than 35 percent rock fragments and are on mountain sides.
DRAINAGE AND PERMEABILITY: Well drained, very rapid runoff, moderately slow to slow permeability.
USE AND VEGETATION: Used for livestock grazing and wildlife habitat. Native vegetation is Gambel oak, New Mexico locust, and ponderosa pine with an understory of Arizona fescue, Parry's oatgrass, nodding brome, sedge, and bluegrass.
DISTRIBUTION AND EXTENT: Southeastern Colorado. LRR E, MLRA's 48A, 49. The soils of this series are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Las Animas County Soil Survey, Las Animas County, Colorado, 2007.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Particle size control section: the zone from 14 to 34 inches. (Bt1 and Bt2 horizons)
Mollic epipedon: the zone from 0 to 9 inches. (A1 and A2 horizons)
Argillic horizon: the zone from 14 to 47 inches. (Bt1, Bt2, and Bt3 horizons)
The Fishers series was originally classified as Loamy-skeletal, mixed, mesic Aridic Haplustolls, but was determined to have an argillic horizon and to be in a frigid temperature regime. These soils are borderline to Mollisols but have an argillic horizon that exceeds the two-thirds thickness limitation for mollisols. The original type location is not mapped as the series was formerly classified. This revision documents the class change. Last updated by the state 4/2001.