LOCATION GARZA              WY
Tentative Series
Rev. AJC/JS
03/1999

GARZA SERIES


Typically they have friable granular noncalcareous A horizons and medium to moderately fine textured calcareous C horizons that lack continuous subhorizons of visible secondary calcium carbonate accumulation.

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Pachic Haplustolls

TYPICAL PEDON: Garza loam - grassland. (Colors are for dry soil unless otherwise noted)

A11--0 to 8 inches; dark grayish brown (10YR 4/2) loam, very dark brown (10YR 2/2) moist; moderate medium granular and crumb structure; soft, very friable, slightly plastic, slightly sticky; noncalcareous; mildly alkaline, pH 7.4 (PR); clear smooth boundary. (6 to 20 inches thick)

A12--8 to 24 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; horizon is slightly hard, very friable, slightly plastic, slightly sticky; peds are hard; calcareous; moderately alkaline, pH 8.0 (CR); clear wavy boundary. (10 to 20 inches thick)

C--24 to 60 inches; grayish brown (10YR 5/2) loam, dark grayish brown (10YR 4/2) moist; massive; hard, friable, slightly plastic, slightly sticky; noncalcareous; mildly alkaline, pH 7.4 (PR); clear smooth boundary. (6 to 20 inches thick)

A12--8 to 24 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; horizon is slightly hard, very friable, slightly plastic, slightly sticky; peds are hard; calcareous; moderately alkaline, pH 8.0 (CR); clear wavy boundary. (10 to 20 inches thick)

C--24 to 60 inches; grayish brown (10YR 5/2) loam, dark grayish brown (10YR 4/2) moist; massive; hard, friable, slightly plastic, slightly sticky; calcareous; moderately alkaline pH 8.2 (CR).

TYPE LOCATION: Carbon County, Wyoming. The SW 1/4 of the SW 1/4 of sec. 13, T. 19 N., 89 W.

RANGE IN CHARACTERISTICS: These soils lack cambic horizons or characteristics of the mollic epipedon that are equivalent of cambic horizons. Unless otherwise stated the entire range of properties permissible for the diagnostic horizons and the subgroup and family are also permissible for the series. Depth to uniformly calcareous material ranges from 0 to 10 inches but should not exceed 1/2 the thickness of the mollic epipedon. Exchangeable sodium ranges from 0 to 15 percent except that a few subhorizons totaling less than 4 inches in thickness that exceed 15 percent may occur discontinuously in some pedons. Weighted average gypsum content of the control section ranges from 0 to 5 percent, and a majority of subhorizons above 20 inches should not exceed 3 percent.

Continuous concentrated horizons of visible secondary calcium carbonate and/or sulfate should not occur within the control section although some visible calcium carbonate and/or sulfate may occur discontinuously at any depth. Depth to a lithic contact, a paralithic contact, or to skeletal materials ranges from 40 to more than 60 inches. content of coarse fragments ranges from 0 to 15 percent in a major part of the control section and coarse fragments ranging from 1/2 to 10 inches in diameter predominate. Mottling ranges from no mottling to a few faint mottles but when mottled the base chroma of the matrix must exceed.

The control section is uniform with only minor contrasting strata. The soils are dry more than half the time that soil temperature is 41 degrees F. or higher. Color of the A may range in hue from 5Y to 7.5YR, in value from 4 to 5 dry or 2 to 3 moist, and in chroma from 1 to 3. Reaction normally ranges from neutral to mildly alkaline (1:5 dilution unbuffered organic dye). Calcium carbonate equivalent ranges from 1 to 10 percent. Texture is usually a loam or clay loam averaging 18 to 35 percent clay, 20 to 55 percent silt, and 20 to 55 percent sand with more than 15 percent but less than 35 percent fine or coarser sand.

COMPETING SERIES: These are the Arnegard, Falkirk, Roseglen, and Shawa series. These soils are noncalcareous in the upper solum.

GEOGRAPHIC SETTING: The Garza series occurs on gently to moderately sloping alluvial fans and valley sideslopes. Slopes typically range from about 2 to 30 or more percent. The soil is developing in thick calcareous alluvial fan materials derived principally from sedimentary bedrock. At the type location the mean annual precipitation is about 14 inches with peak periods of precipitation occurring in the spring and early summer months. Mean annual air temperature is 40 degrees f., mean summer air temperature is 62 degrees F., mean annual soil temperature is 44 degrees F., and mean summer soil temperature is 63 degrees F.

GEOGRAPHICALLY ASSOCIATED SOILS: These include the Forelle and Sagecreek series. The Forelle series differs in having an ochric epipedon and an argillic horizon. The Sagecreek series differs in having an ochric epipedon and a cambic horizon.

DRAINAGE AND PERMEABILITY: Well to moderately well drained. Runoff is slow to medium and permeability is moderate to slow.

USE AND VEGETATION: They are used principally as native pastureland. Native vegetation includes basin wild rye, big sage, and western wheatgrass.

DISTRIBUTION AND EXTENT: Present known distribution limited to southern and central Wyoming. Series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES PROPOSED: Sage Creek area, Carbon County, Wyoming, 1972. Series name is a coined name.

OSED scanned by NSSQA. Last revised by state on 2/72.


National Cooperative Soil Survey
U.S.A.