LOCATION ZOPILOTE                CO

Established Series
Rev. JPP/TWH/KLS
04/2018

ZOPILOTE SERIES

The Zopilote series consists of very deep, well drained soils that formed in debris flow deposits derived from sandstone and shale. Zopilote soils are on debris flows. Slopes range from 3 to 8 percent. Mean annual precipitation is about 356 mm and the mean annual air temperature is about 9.4 degrees C.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, calcareous, mesic Aridic Ustorthents

TYPICAL PEDON: Zopilote very stony sandy clay loam, on a south facing, simple, 3 percent slope in pinyon-juniper at an elevation of 1,859 meters. (Colors are for dry soil unless otherwise noted.) When described on May 21, 1996 the soil was dry from 0 to 152 cm. The surface is covered by 10 percent cobble, 20 percent stones, and 2 percent boulders.

A--0 to 15 cm; light brownish gray (10YR 6/2) very stony sandy clay loam, dark grayish brown (10YR 4/2) moist; moderate fine granular structure; soft, very friable, slightly sticky and slightly plastic; few fine and medium roots; 10 percent gravel, 20 percent cobble, 15 percent stones, 2 percent boulders; slightly effervescent; carbonates disseminated; 2 percent calcium carbonate equivalent; slightly alkaline (pH 7.6); clear wavy boundary. (8 to 25 cm thick)

C1--15 to 102 cm; light brownish gray (10YR 6/2) stratified very stony sandy loam and very stony loam, dark grayish brown (10YR 4/2) moist; massive; soft, very friable, nonsticky and nonplastic; few fine and medium roots; few fine and medium pores; 10 percent gravel, 20 percent cobble, 15 percent stones, 2 percent boulders; slightly effervescent; carbonates disseminated; 2 percent calcium carbonate equivalent; moderately alkaline (pH 8.0); gradual wavy boundary. (51 to 102 cm thick)

C2--102 to 203 cm; gray (10YR 6/1) stratified extremely cobbly sandy loam and extremely cobbly loam, dark grayish brown (10YR 4/2) moist; massive; soft, very friable; nonsticky and nonplastic; 40 percent gravel, 20 percent cobble, 5 percent stones, 5 percent boulders; slightly effervescent; carbonates disseminated; 2 percent calcium carbonate equivalent; moderately alkaline (pH 8.4).

TYPE LOCATION: Archuleta County, Colorado; about 40 kilometer east of Ignacio; located about 30 meters south and 305 meters west of the northeast corner of Sec. 14, T. 32 N., R. 5 W.; Carracas USGS quad; Lat. 37 degrees, 01 minutes, 27 seconds, N. and Long. 107 degrees, 21 minutes, 20 seconds, W., NAD 27.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 10.0 to 11.7 degrees C.
Depth to carbonates: 0 to 25 cm

Particle-size control section (weighted average):
Clay content: 10 to 22 percent
Rock fragment content: 35 to 80 percent

A horizon
Value: 5 or 6 dry, 3 or 4 moist
Chroma: 2 or 3, dry or moist
Calcium carbonate equivalent: 0 to 2 percent
Reaction (pH): 6.6 to 7.8

C horizon
Value: 5 or 6 dry, 4 or 5 moist
Chroma: 1 to 3, dry or moist
Texture, fine earth fraction: sandy loam, loam, sandy clay loam
Clay content: 10 to 22 percent
Rock fragment content: 35 to 80 percent
Calcium carbonate equivalent: 1 to 5 percent
Reaction (pH): 7.4 to 8.4

COMPETING SERIES: None listed.

GEOGRAPHIC SETTING:
Landform - debris flow
Elevation - 1,830 to 1,980 meters
Slopes - 3 to 8 percent
Parent material - debris flow deposits derived from sandstone and shale
Mean annual air temperature - 8.9 to 10.0 degrees C.
Mean annual precipitation - 330 to 380 cm
Precipitation pattern - May and June are the driest months; July and August are the wettest months
Frost-free period - 120 to 130 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed.

DRAINAGE AND PERMEABILITY: Well drained, medium runoff, moderately rapid permeability.

USE AND VEGETATION: These soils are used for livestock grazing and wildlife habitat. Native vegetation is twoneedle pinyon, Utah juniper, blue grama, Indian ricegrass, galleta, and big sagebrush.

DISTRIBUTION AND EXTENT: Southwest Colorado; LRR D, MLRA 36; small extent.

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

SERIES PROPOSED: Archuleta County, Colorado, Archuleta soil survey area, 2002. The name is taken from a mountain peak in the vicinity.

REMARKS:
Diagnostic horizons and features recognized in this pedon are:
Stratified horizons - 15 to 203 cm (C1 and C2 horizons)
Particle-size control section - 25 to 100 cm (part of the C1 horizon)

Zopilote soils have a mesic temperature regime and an ustic soil moisture regime bordering on aridic.

---

National Cooperative Soil Survey
U.S.A.