LOCATION STARDUST IDEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Ultic Argixerolls
TYPICAL PEDON: Stardust fine gravelly loam, forested -- on a 20 percent slightly convex south-facing slope at 3,075 feet elevation. When described on May 28, 1997, the soil was slightly moist throughout. (Colors are for air-dry soil unless otherwise noted.)
Oi--0 to 1 inch; slightly decomposed forest litter.
A1--1 to 3 inches; grayish brown (10YR 5/2) fine gravelly loam, very dark grayish brown (10YR 3/2) moist; weak fine and medium subangular blocky structure parting to moderate fine and medium granular; soft, very friable, slightly sticky and slightly plastic; many very fine and fine, few medium roots; many very fine and fine, few medium irregular and tubular pores; 15 percent fine gravel; slightly acid (pH 6.5); clear smooth boundary.
A2--3 to 9 inches; grayish brown (10YR 5/2) fine gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine, few medium roots; common very fine and fine, few medium tubular pores; 15 percent fine gravel; slightly acid (pH 6.1); clear smooth boundary. (combined A horizon - 8 to 20 inches thick)
Bt1--9 to 18 inches; brown (10YR 5/3) fine gravelly loam, dark brown (10YR 3/3) moist; moderate fine and medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; common very fine and fine, few medium roots; common very fine and fine, few medium tubular pores; common faint clay films on faces of peds and in pores; 15 percent fine gravel; moderately acid (pH 5.7); clear smooth boundary. (6 to 12 inches thick)
Bt2--18 to 38 inches; yellowish brown (10YR 5/4) fine gravelly sandy clay loam, dark yellowish brown (10YR 3/4) moist; moderate medium and coarse subangular blocky structure; hard, firm, moderately sticky and moderately plastic; few very fine, fine and medium roots; common very fine and fine tubular pores; many faint clay films on faces of peds and in pores; 15 percent fine gravel; moderately acid (pH 5.6); clear smooth boundary. (10 to 24 inches thick)
Bt3--38 to 54 inches; pale brown (10YR 6/3) gravelly sandy clay loam, brown (10YR 4/3) moist; moderate fine and medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; few very fine, fine and medium roots; common very fine and fine tubular pores; many faint clay films on faces of peds and in pores; 20 percent gravel; moderately acid (pH 5.6); clear smooth boundary. (0 to 20 inches thick)
BC--54 to 67 inches; light yellowish brown (10YR 6/4) gravelly sandy loam, dark yellowish brown (10YR 4/4) moist; weak fine and medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; few very fine and fine roots; common very fine, fine and medium tubular pores; 25 percent gravel; moderately acid (pH 5.6).
TYPE LOCATION: Boise County, Idaho; about 1 mile southwest of Crouch; 1,100 feet north and 1,700 feet west of the southeast corner of section 16, T.9 N., R.4 E.; USGS Garden Valley Quadrangle; Latitude - 44 degrees, 06 minutes, 35 seconds N. and Longitude - 115 degrees, 59 minutes, 04 seconds W.; NAD 83.
RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon - 10 to 20 inches
Depth to base of argillic horizon - 45 inches or more
Depth to bedrock - 60 inches or more
Reaction - moderately acid or slightly acid
Base saturation - 50 to 75 percent
Particle-size control section - 18 to 30 percent clay; 5 to 30 percent rock fragments; more than 25 percent medium or coarser sand
Moisture control section - dry 60 to 90 consecutive days following the summer solstice
Average annual soil temperature - 47 to 50 degrees F.
A horizon
Hue - 7.5YR or 10YR
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 2 or 3 dry or moist
Clay content - 15 to 25 percent
Rock fragments - 5 to 25 percent fine gravel
Bt1 horizon
Hue - 7.5YR or 10YR
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 3 or 4 dry or moist
Texture - L or SCL
Clay content - 18 to 30 percent
Rock fragments - 5 to 25 percent fine gravel
Bt2 horizon
Hue - 7.5YR or 10YR
Value - 6 or 7 dry, 4 or 5 moist
Chroma - 3 or 4 dry or moist
Texture - L or SCL
Clay content - 18 to 30 percent
Rock fragments - 5 to 35 percent gravel
COMPETING SERIES: These are the Alderpoint (T), Annum, Brownlee, Chirpchatter, Dryfalls (T), Ebadlow, Felton, Fisherhill, Goldendale, Hellake, Lompico, Lorena, Meland, Mendian (T), Meystre, Quiden, Rehfield, Robbscreek, Schumacher, Stacker, Updegraff and Van Horn series. Annum soils are 40 to 60 inches deep to a paralithic contact and are dry for more than 90 consecutive days. Boyleston and Mendian soils have a mantle of loess, have buried Bt horizons, and are dry for more than 90 consecutive days. Brownlee soils do not have O horizons, are typically 40 to 60 inches deep over weathered granite, and have few to common lamellae in the lower part of the argillic horizon. Chirpchatter soils are dry 120 to 140 days. Lompico, Lorena, Meland, Robbscreek and Stacker soils are 20 to 40 inches deep. Dryfalls soils are 40 to 60 inches deep and are influenced by ash in the upper 7 to 14 inches. Ebadlow soils are dry 90 to 105 days and are moderately deep to skeletal material. Felton soils have more than 50 percent shale fragments in the C horizons and are dry for more than 90 consecutive days. Fisherhill soils are dry 90 to 105 days and have an average annual soil temperature of 52 to 54 degrees F. Goldendale and Meystre soils have less than 5 percent rock fragments and less than 25 percent medium sand or coarser in the particle-size control section. Hellake soils are less than 45 inches deep to the base of the Bt horizon, have less than 25 percent medium and coarser sand, and have a substratum discontinuity. Quiden soils have a mean annual soil temperature of 50 to 54 degrees F and have less than 25 percent medium and coarser sand. Rehfield soils are dry for more than 90 consecutive days, and are 40 to more than 60 inches deep to bedrock. Schumacher soils have less than 25 percent medium or coarser sand in the particle-size control section, are dry for 45 to 60 consecutive days, and are 40 to 60 inches deep to lithic bedrock. Updegraff soils are dry more than 90 consecutive days and are 40 to 60 inches deep. Van Horn soils have an average annual soil temperature 51 to 54 degrees F. Alderpoint soils are not currently in the database and cannot be competed.
GEOGRAPHIC SETTING: Stardust soils are nearly level to moderately steep on fan remnants and landslides at elevations of 2,700 to 5,000 feet. These soils formed in alluvium from granitic rocks. Slopes range from 1 to 25 percent. Average annual precipitation is 20 to 26 inches. Average annual temperature is 45 to 48 degrees F. Frost-free period is 90 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Cloudyway, Huston, Riverpoint and the competing Hellake soils. Cloudyway soils are coarse-loamy, do not have an argillic horizon and occur on similar geomorphic positions. Huston soils are loamy-skeletal and occur on fan remnant escarpments. Riverpoint soils are loamy-skeletal and occur on small splays. Hellake soils are on relict lakebed terraces and landslides.
DRAINAGE AND PERMEABILITY: Well drained; very slow to rapid runoff; moderate permeability. On nearly level areas all or part of the pedon is commonly saturated during the growing season due to flood irrigation.
USE AND VEGETATION: Stardust soils are used mainly for irrigated pasture/hayland and timber production. Native vegetation is ponderosa pine and common snowberry.
DISTRIBUTION AND EXTENT: West-central Idaho. MLRA 44 and 43b. Stardust soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Boise County Area, Idaho, Parts of Ada and Boise Counties, 2005.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Mollic epipedon - zone from 1 to 18 inches (A1, A2 and Bt1 horizons)
Argillic horizon - zone from 9 to 54 inches ( Bt1, Bt2 and Bt3 horizons)
Particle-size control section - zone from 9 to 29 inches
Soil moisture regime - xeric
Significant Fe concentrations present in some pedons are due to continuous flood irrigation during the growing season and not related to natural drainage conditions.
All depths related to diagnostic horizons and features listed in the range of characteristics are measured from the top of the first mineral horizon.