LOCATION TRAILCREEK IDEstablished Series
TAXONOMIC CLASS: Ashy, glassy, frigid Humic Vitrixerands
TYPICAL PEDON: Trailcreek very fine sandy loam - on a 40 percent southwest slope in rangeland at 5,400 feet elevation. (Colors are for air dry soil unless otherwise stated. When described on July 14, 1981, the soil was dry throughout.)
A--0 to 4 inches; grayish brown (10YR 5/2) very fine sandy loam, very dark grayish brown (10YR 3/2)9moist; weak medium and fine subangular blocky structure parting to weak fine granular; soft, very friable, nonsticky and slightly plastic; many very fine, common fine, and few medium roots; many very fine irregular and many very fine tubular pores; neutral (pH 6.6); abrupt wavy boundary. (3 to 8 inches thick)
BA--4 to 12 inches; grayish brown (10YR 5/2) very fine sandy loam, dark brown (10YR 3/3) moist; weak medium and fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine and few medium roots; many very fine irregular and common very fine tubular pores; neutral (pH 6.8); clear wavy boundary. (0 to 10 inches thick)
Bw--12 to 20 inches; grayish brown (10YR 5/2) very fine sandy loam, dark brown (10YR 3/3) moist; weak coarse and medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine and fine and few medium roots; many very fine irregular and common fine tubular pores; neutral (pH 6.8); clear wavy boundary. (6 to 18 inches thick)
BC--20 to 26 inches; light brownish gray (10YR 6/2) very fine sandy loam, brown (10YR 4/3) moist; massive; soft, very friable, nonsticky and nonplastic; 20 to 45 percent pebble and cobble size fragments of consolidated volcanic ash; many very fine, common fine, and few medium roots; many very fine irregular and many very fine tubular pores; neutral (pH 6.7); abrupt wavy boundary. (4 to 18 inches thick)
Cr--26 inches; light gray (2.5Y 7/) consolidated volcanic ash, gray (2.5Y 6/) moist.
TYPE LOCATION: Bannock County, Idaho; about 9.5 miles west of Arimo; 2,000 feet east and 900 feet south of the northwest corner of section. 15, T. 10 S., R. 35 E.
RANGE IN CHARACTERISTICS:
Thickness of the solum - 20 to 40 inches
Depth to paralithic contact - 20 to 40 inches
Calcium carbonate content - may be present in the lower part of some pedons and as seams in cracks of the consolidated ash Average annual soil temperature - 43 to 47 degrees F.
A horizon
Color hue - 2.5Y or 10YR
Value, dry - 4 through 6
Value, moist - 2 or 3
Chroma, dry or moist - 2 or 3
Reaction - neutral or mildly alkaline
Bw horizon
Color hue - 2.5Y or 10YR
Value, dry - 5 through 7
Value, moist - 3 through 6
Chroma, dry or moist - neutral through 3
Reaction - neutral through moderately alkaline
COMPETING SERIES: These are the Coalbank (T) and Cottonthomas (T) series. Coalbank soils are deep or very deep to a paralithic contact. Cottonthomas soils are very deep and have Bk horizons.
GEOGRAPHIC SETTING: Trailcreek soils are on mountainsides, foothills, and terraces. Slopes range from 12 to 50 percent. They formed in alluvium and residuum from consolidated volcanic ash. Average annual precipitation is about 14 to 18 inches. Average annual temperature is about 41 to 45 degrees F. Frost-free period is 70 to 90 days. Elevation ranges from 4,800 to 6,000 feet.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bancroft, Cedarhill (T), Coalbank (T), Hades, Hondoho, Lonigan (T), Ririe, and Watercanyon (T) soils. All of these soils, except Lonigan, lack a paralithic contact at depths of 20 to 40 inches. Lonigan soils are ashy-skeletal. Coalbank soils are in slightly concave positions or on north and east-facing slopes. Lonigan soils are on convex positions and are generally on south and west-facing slopes. Cedarhill soils are associated with limestone on mountain slopes. Bancroft, Ririe, and Watercanyon soils formed in loess and are on fan terraces and hillslopes. Hondoho soils are skeletal and formed in alluvium from quartzite and are on terrace breaks. Hades soils formed in silty alluvium and are generally in concave positions on similar landscapes.
DRAINAGE AND PERMEABILITY: Well drained; runoff is medium to very rapid; permeability is moderately rapid.
USE AND VEGETATION: Trailcreek soils are used mostly for rangeland but a few areas are used for nonirrigated farmland. Important native plants are mountain big sagebrush, antelope bitterbrush, bluebunch wheatgrass, and Indian ricegrass. Wheat and barley are grown in the areas that are farmed.
DISTRIBUTION AND EXTENT: Southeastern Idaho. This series is inextensive. SERIES ESTABLISHED: Bannock County, Idaho, 1983.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon