LOCATION APRON WY+MT

Established Series
Rev. PSD//DEW/JCK
07/2015

APRON SERIES

The Apron series consists of very deep, well drained soils that formed in alluvium or slope alluvium from calcareous sandstone interbedded with shale. These soils are on fan aprons, alluvial fans, fan remnants and stream terraces. Slopes are 0 to 15 percent. Mean annual precipitation is about 191 mm, mean annual air temperature is about 7 degrees C.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, calcareous, mesic Typic Torriorthents

TYPICAL PEDON: Apron fine sandy loam in rangeland at an elevation of 1,587 meters (colors are for dry soil unless otherwise noted).

A--0 to 15 cm; light brownish gray (2.5Y 6/2) fine sandy loam, dark grayish brown (2.5Y 4/2) moist; moderate fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine roots throughout; common very fine and fine vesicular pores; strongly effervescent; moderately alkaline (pH 8.2); gradual smooth boundary. (8 to 20 cm thick)

C--15 to 152 cm; light yellowish brown (2.5Y 6/3) sandy loam, light olive brown (2.5Y 5/3) moist; massive; slightly hard, very friable, nonsticky and nonplastic; common very fine and fine roots; common very fine and fine tubular pores; 5 percent gravel; strongly effervescent; moderately alkaline (pH 8.4).

TYPE LOCATION: Fremont County, Wyoming; 375 meters south and 578 meters west of the northeast corner of section. 14, T. 4N, R. 3E. Mexican Pass SW USGS quadrangle; latitude 43 degrees 19 minutes 38.48 seconds N. longitude 108 degrees 29 minutes 13.0 seconds W., NAD 83.

RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 8 to 10 degrees C
Particle-size control section - 5 to 18 percent clay
Rock fragments - 0 to 15 percent gravel

A horizon
Hue: 10YR to 5Y
Value: 5, 6 or 7 dry; 4 or 5 moist
Chroma: 2 or 3
Texture: fine sandy loam or sandy loam
Clay content: 5 to 18 percent
Reaction: 7.4 to 8.4

C horizon
Hue: 10YR to 5Y
Value: 5, 6 or 7 dry; 4, 5 or 6 moist
Chroma: 2, 3 or 4
Texture: sandy loam or fine sandy loam
Clay content: 5 to 18 percent
Reaction: 7.9 to 8.6

COMPETING SERIES:
Fang (NV) - have a lithologic discontinuity; have pyroclastic materials in the subsoil
Fruitland (NM) - have a mean annual soil temperature greater than 10 degrees C
Ganaflan (NV) - have a paralithic contact at depths of 50 to 100 cm; have more than 15 percent rock fragments in the particle-size control section
Geer (NV) - have pyroclastic materials throughout the profile; have a mean annual soil temperature greater than 10 degrees C
Jeddito (AZ) - have stratified textures of sand and clay in the subsoil
Jenrid (UT) - have hue redder than 10YR
Kumiva (NV) - have a horizon of secondary calcium carbonate accumulation; have a mean annual soil temperature greater than 10 degrees C
Marcou (AZ) - have hue redder than 10YR; have a mean annual soil temperature greater than 10 degrees C
Mazuma (NV) - have a horizon of secondary calcium carbonate accumulation; have a sodium adsorption ratio greater than 13 meq/L
Moepitz (UT) - have a lithic contact at depths of 50 to 100 cm; have hue redder than 10YR
Piltdown (NV) - are stratified with very fine sandy loam and thin layers of gravel in the particle-size control section
Shotnick (UT) - have hue redder than 10YR
Sodaspring (NV) - have greater than 15 percent rock fragments in the particle-size control section; have a mean annual soil temperature greater than 10 degrees C
Tooele (UT) - have exchangeable sodium greater than 15 percent and calcium carbonate equivalent greater than 10 percent in the particle-size control section
Trachute (UT) - have a horizon of gypsum accumulation; have hue redder than 10YR
Vanderhoff (ID) - have a paralithic contact at depths of 50 to 100 cm
Wentridge (UT) - have a horizon of gypsum accumulation; have a paralithic or lithic contact at depths of 50 to 100 cm
Worland (WY) - have a paralithic contact at depths of 50 to 100 cm

GEOGRAPHIC SETTING:
Landform - fan aprons, alluvial fans, fan remnants, and stream terraces
Elevation - 1,200 to 1,700 meters
Slope - 0 to 15 percent
Parent material - alluvium or slope alluvium
Mean annual precipitation - 125 to 230 mm
Mean annual air temperature - 6 to 8 degrees C
Frost-free period - 110 to 150 days

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Lostwells and Oceanet soils and the competing Worland soils. Lostwells soils are fine-loamy. Oceanet soils have a paralithic contact at depths of less than 50 cm.

DRAINAGE AND PERMEABILITY: Well drained; moderately rapid permeability.

USE AND VEGETATION: Apron soils are used for irrigated cropland, rangeland, and wildlife habitat. Common crops are barley, dry edible beans, sugar beets, and corn. Native vegetation is needleandthread, Indian ricegrass, blue grama, plains pricklypear, yucca, and Wyoming big sagebrush.

DISTRIBUTION AND EXTENT: Apron soils are extensive in north central Wyoming and south central Montana. MLRA 32, 34A, and 58A.

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

SERIES ESTABLISHED: Fremont County, Wyoming, Riverton Irrigated Area; 1969.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - from 0 to 15 cm (A horizon)
Particle-size control section - from 25 to 100 cm (part of the C horizon)

Apron soils have a mesic temperature regime and an aridic moisture regime.

National Cooperative Soil Survey
U.S.A.