LOCATION LAZEAR             CO+UT WY
Established Series
Rev. GB/CSW/JWB
05/2008

LAZEAR SERIES


The Lazear series consists of shallow, well drained soils that formed in colluvium, slope alluvium and residuum derived from interbedded shale, loamstone, limestone and sandstone. Lazear soils are on structural benches, ledges, hills, mesas, and ridges. Slopes range from 0 to 65 percent. Mean annual precipitation is about 12 inches and the mean annual temperature is about 53 degrees F.

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 4 inches; light brownish gray (10YR 6/2) gravelly loam, dark grayish brown (10YR 4/2) moist; moderate fine granular structure; soft, very friable; 15 percent sandstone gravel; strongly effervescent; moderately alkaline (pH 8.2); clear smooth boundary. (2 to 5 inches thick)

C--4 to 14 inches; light brown (7.5YR 6/3) gravelly loam, brown (7.5YR 4/3) moist; massive; slightly hard, very friable; 20 percent sandstone gravel; strongly effervescent; moderately alkaline (pH 8.2); abrupt wavy boundary.

R--14 inches; 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:

Soil moisture regime: aridic bordering on ustic

Soil temperature regime: mesic

Mean annual soil temperature: 47 to 58 degrees F

Mean summer soil temperature: 60 to 78 degrees F

Particle-size control section: 18 to 35 percent clay

Depth to lithic contact: 10 to 20 inches to hard calcareous sedimentary rock

A horizon:
Hue: 7.5YR or 10YR
Value: 5 to 7 dry, 3 to 5 moist
Chroma: 2 to 4 dry or moist
Rock fragments: 0 to 35 percent
EC (mmhos/cm): 0 to 2
Reaction: slightly to strongly alkaline

C horizon:
Hue: 7.5YR to 2.5Y
Value: 5 to 8 dry, 4 to 6 moist
Chroma: 2 to 4 dry or moist
Texture: fine sandy loam, loam, clay loam, channery fine sandy loam, gravelly loam, channery loam
Rock fragments: 0 to 35 percent
Calcium carbonate equivalent: 1 to 15 percent
EC (mmhos/cm): 0 to 4
Reaction: slightly to strongly alkaline

COMPETING SERIES: These are the Bigmon, Hideout, Kenzo, Redspear, Rizno, Rizozo, Skyvillage, Travessilla, Travson, and Zukan series. Bigmon, Hideout, Rizno, Skyvillage, Travessilla, and Travson soils have less than 18 percent clay in the particle-size control section. Redspear, and Rizozo soils have hues of 5YR or redder. Kenzo soils have hues of 7.5YR or redder and have less than 18 percent clay in the particle-size control section. Zukan soils are over limestone bedrock and have a horizon of carbonate accumulation.

GEOGRAPHIC SETTING:

Parent material: colluvium, slope alluvium, residuum derived from interbedded shale, loamstone, sandstone and limestone

Landform: structural benches, ledges, hills, mesas, and ridges

Slopes: 0 to 65 percent

Elevation: 4,700 to 6,800 feet

Mean annual temperature: 45 to 56 degrees F

Mean annual precipitation: 9 to 13 inches

Frost-free period: 120 to 150 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Shavano soils and the competing Travessilla soils. Shavano soils have a lithic contact at depths greater than 20 inches and Travessilla soils contain less than 18 percent clay in the particle-size control section.

DRAINAGE AND PERMEABILITY: well drained, low to high runoff, moderate permeability

USE AND VEGETATION: These soils are used principally as native pastureland. Native vegetation is galleta grass, cactus, greasewood, and snakeweed.

DISTRIBUTION AND EXTENT: The foothill areas of western and southwest Colorado and adjacent parts of Wyoming; central Utah. LRR D, MLRA 34B and 35. This series is extensive.

MLRA OFFICE RESPONSIBLE: Lakewood, Colorado

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

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon: The zone from 0 to 4 inches. (A horizon)

Lithic contact: The zone at 14 inches. (R horizon)

Secondary carbonates usually coat the surface of the bedrock.

Particle-size control section: The zone from 0 to 14 inches. (A and C horizons)

Last updated by the state: 3/04.

Soil Taxonomy Second Edition, 1999


National Cooperative Soil Survey
U.S.A.