LOCATION WANETTA MTEstablished Series
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, mesic Aridic Haplustalfs
TYPICAL PEDON: Wanetta loam - cheatgrass and crested wheatgrass abandoned cropland. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 6 inches; light brownish gray (10YR 6/2) loam, dark grayish brown (10YR 4/2) moist; coated with grayish brown (10YR 5/2), very dark grayish brown (10YR 3/2) moist; moderate fine granular structure; soft, very friable, slightly sticky, slightly plastic; many very fine roots; many very fine and fine interstitial pores; neutral.
B2t--6 to 14 inches; brown (10YR 5/3) clay loam, dark brown (10YR 4/3) moist; coated with dark brown (10YR 4/3), dark brown (10YR 3/3) moist; strong medium prismatic structure that separates to moderate medium blocks; very hard, friable, slightly sticky, slightly plastic; many very fine roots; many very fine and fine tubular pores; varnish-like organically stained film on faces of peds; mildly alkaline; clear boundary. (6 to 10 inches thick)
B3--14 to 17 inches; grayish brown (2.5Y 5/2) heavy loam, dark grayish brown (2.5Y 4/2) moist; weak medium prismatic structure; hard, friable, slightly sticky, slightly plastic; common very fine roots; many very fine and fine tubular pores; few patches of varnish-like film on faces of peds; mildly alkaline; clear boundary. (2 to 4 inches thick)
C1ca--17 to 32 inches; light brownish gray (2.5Y 6/2) loam grading to gravelly loam in lower part, light olive brown (2.5Y 5/3) moist; massive; hard, very friable, slightly sticky, slightly plastic; few very fine roots; common very fine and fine tubular pores; strongly calcareous with many medium and large soft white masses of lime; moderately alkaline; abrupt boundary. (8 to 20 inches thick)
IIC2--32 to 40 inches; very gravelly loamy sand; moderately calcareous with lime crusts on pebbles; abrupt boundary. (0 to 8 inches thick)
IIC3--40 to 60 inches; loose sand and gravel; calcareous.
TYPE LOCATION: Treasure County, Montana; 0.25 mile south and 0.2 mile west of NW corner of sec. 13, T.6N., R.37E.
RANGE IN CHARACTERISTICS: Depth to sand and gravel is 20 to 40 inches. Depth to the Cca horizon is 12 to 20 inches. Volume of gravel in the pedon above the very gravelly loamy sand C horizon ranges up to 30 percent. The content of organic carbon in the upper 15 inches is 1 to 1.5 percent, and the weighted average sand/clay ratio is 1 to 2. Wanetta soils are usually dry but their surfaces are moistened by occasional summer rains. Mean annual soil temperature is 47 to 50 degrees F. Virgin pedons have 2- to 4-inch thick loam A1 horizons and 3- to 5-inch thick loam A&B horizons. The Ap horizon has hue of 10YR or 2.5Y, value of 5 or 6 dry, and chroma of 2 or 3. The B2t horizon has hue of 10YR or 2.5Y, value of 5 or 6 dry with coats of 4 or 5 and with chroma of 3 or 4. It has 15 to 35 percent fine or coarser sand and 28 to 35 percent clay with an absolute increase of 5 to 10 percent clay over the Ap horizons and as much as 15 percent more clay than in the A1 horizons. This horizon has moderate to strong prismatic and blocky structure.
COMPETING SERIES: These are the Altvan, Larim, Larimer, Naturita, Vernal and Yoder series. Altvan soils have mollic epipedons. Larim soils have more than 35 percent gravel in their Bt horizons and they are 11 to 20 inches deep over sand and gravel. Larimer soils have from 0.8 to 1 percent organic carbon in the upper 15 inches and they lack the increase in value from coated to rubbed soil in the A and B horizons. Naturita soils have calcareous A and B horizons. Vernal soils have hue of 7.5YR or 5YR. Yoder soils are noncalcareous.
GEOGRAPHIC SETTING: Wanetta soils occur on nearly level to sloping alluvial fans and terraces at elevations of 2,500 to 3,500 feet. The soils formed in calcareous alluvium of mixed mineralogy. The climate is semiarid continental with 10 to 14 inches mean annual precipitation, mean annual temperature of 44 to 48 degrees F., average July temperature of 73 degrees F., average January temperature of 22 degrees F. and a frost-free period of 110 to 140 days. Seventy-five percent of the mean annual precipitation is distributed through the six-month period of April through September.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bew, Fort Collins, Hesper, Olney, Toluca, and the competing Larim soils. Bew, Fort Collins, Hesper, Olney, and Toluca soils are deeper than 40 inches to the sandy and gravelly substrata.
DRAINAGE AND PERMEABILITY: Well-drained; moderately permeable.
USE AND VEGETATION: Used extensively for irrigated crop production, for dry farm crop production and for range, Associations of short and mid grasses make up the native vegetation.
DISTRIBUTION AND EXTENT: Wanetta series is distributed throughout southeast Montana. It is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Denver, Colorado
SERIES ESTABLISHED: Treasure County, Montana, 1961.
REMARKS: Wanetta soils formerly were classified as Brown soils.
OSED scanned by SSQA. Last revised by state 10/71.