LOCATION LAZEAR                  CO+UT

Established Series
Rev. GB/CRP/JCK
12/2017

LAZEAR SERIES

The Lazear series consists of shallow, well drained soils that formed in colluvium or slope alluvium over residuum derived from interbedded sedimentary rock. Lazear soils are on structural benches, canyon walls, dip slopes, scarp slopes and homoclinal ridges. Slopes are 0 to 75 percent. Mean annual precipitation is about 279 mm and the mean annual air temperature is about 11 degrees C.

TAXONOMIC CLASS: Loamy, mixed, superactive, calcareous, mesic Lithic Ustic Torriorthents

TYPICAL PEDON: Lazear gravelly loam in grassland. (Colors are for dry soil unless otherwise noted.)

A--0 to 10 cm; light brownish gray (10YR 6/2) gravelly loam, dark grayish brown (10YR 4/2) moist; moderate fine granular structure; soft, very friable, slightly sticky and slightly plastic; 15 percent gravel; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (5 to 13 cm thick)

C--10 to 36 cm; light brown (7.5YR 6/3) gravelly loam, brown (7.5YR 4/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; 20 percent gravel; strongly effervescent; moderately alkaline (pH 8.2); abrupt wavy boundary.

R--36 cm; hard calcareous sandstone bedrock.

TYPE LOCATION: Delta County, Colorado; SW 1/4 of the NW 1/4 of sec. 29, T. 4 S., R. 3 E.; Dominguez USGS quad; lat. 38 degrees 46 minutes 57 seconds N. and long. 108 degrees 17 minutes 0.1 seconds W., NAD27

RANGE IN CHARACTERISTICS:
Mean annual soil temperature: 8 to 13 degrees C
Particle-size control section (weighted average):
Clay content - 18 to 35 percent
Rock fragments - 0 to 35 percent

A horizon
Hue: 7.5YR or 10YR
Value: 5, 6 or 7 dry; 3, 4 or 5 moist
Chroma: 2, 3 or 4 dry or moist
Texture: loam, fine sandy loam or sandy loam
Clay content: 15 to 27 percent
Rock fragments: 0 to 35 percent
Reaction: 7.4 to 8.4

C horizon:
Hue: 7.5YR to 2.5Y
Value: 5, 6, 7 or 8 dry; 4, 5 or 6 moist
Chroma: 2, 3 or 4 dry or moist
Texture: loam, sandy loam, fine sandy loam or clay loam
Clay content: 18 to 35 percent
Rock fragments: 0 to 35 percent
Reaction: 7.6 to 8.4

COMPETING SERIES:
Bigmon (CO) - have less than 18 percent clay in the particle-size control section
Cabulla (UT) - have less than 18 percent clay in the particle-size control section
Hideout (UT) - have less than 18 percent clay in the particle-size control section
Kenzo (UT) - have less than 18 percent clay in the particle-size control section
Redspear (WY) - have secondary calcium carbonate accumulation; have less than 18 percent clay in the particle-size control section
Rizno (UT) - have less than 18 percent clay in the particle-size control section
Rizozo (NM) - have hue redder than 7.5YR
Skyvillage (NM) - have less than 18 percent clay in the particle-size control section
Travessilla (NM) - have less than 18 percent clay in the particle-size control section
Travson (WY) - have less than 18 percent clay in the particle-size control section
Zukan (UT) - have secondary calcium carbonate accumulation; have less than 18 percent clay in the particle-size control section

GEOGRAPHIC SETTING:
Landform - structural benches, canyon walls, dip slopes, scarp slopes and homoclinal ridges
Elevation - 1,432 to 2,134 meters
Slope - 0 to 75 percent
Parent material - colluvium or slope alluvium over residuum derived from interbedded sedimentary rock
Mean annual air temperature - 7 to 12 degrees C
Mean annual precipitation - 203 to 305 mm
Frost-free period - 120 to 165 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed.

DRAINAGE AND PERMEABILITY: Well drained, moderate permeability.

USE AND VEGETATION: Lazear soils are used mainly for rangeland. Native vegetation is James' galleta, Indian ricegrass, Utah juniper, shadscale saltbush, squirreltail and winterfat.

DISTRIBUTION AND EXTENT: Lazear soils are of moderate extent in western Colorado and eastern Utah. MLRA 34B and 36.

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

SERIES ESTABLISHED: Delta County, (Paonia Area) Colorado. 1970.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon from - 0 to 10 cm (A horizon)
Particle-size control section from - 0 to 36 cm (A and C horizons)

Lazear soils have mesic soil temperature regime an aridic soil moisture regime bordering on ustic.

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National Cooperative Soil Survey
U.S.A.