LOCATION FIREBOX IDEstablished Series
TAXONOMIC CLASS: Sandy-skeletal, siliceous Xeric Haplocryolls
TYPICAL PEDON: Firebox gravelly loam, rangeland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 3 inches; brown (10YR 5/3) gravelly loam, very dark brown (10YR 2/2) moist; weak very fine and fine subangular blocky structure parting to weak fine granular; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine irregular pores; 30 percent fine gravel; neutral (pH 7.0); clear smooth boundary.
A2--3 to 9 inches; brown (10YR 4/3) very gravelly loam, very dark brown (10YR 2/2) moist; weak very fine and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and few fine roots; common very fine irregular pores; 35 percent gravel; neutral (pH 7.0); clear wavy boundary. (Combined thickness of the A horizons is 9 to 16 inches.)
Bw--9 to 15 inches; dark yellowish brown (10YR 4/4) very gravelly sandy loam, brown (10YR 4/3) moist; weak very fine and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and few fine roots; many very fine irregular pores; 45 percent gravel; neutral (pH 7.2); gradual wavy boundary. (0 to 9 inches thick)
2C1--15 to 21 inches; yellowish brown (10YR 5/4) extremely gravelly loamy coarse sand, dark yellowish brown (10YR 4/4) moist; single grain; loose; common very fine and few fine and medium roots; many very fine and fine irregular pores; 60 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.4); gradual wavy boundary. (4 to 10 inches thick)
2C2--21 to 60 inches; pink (7.5YR 7/4) extremely gravely coarse sand, reddish yellow (7.5YR 6/6) moist; single grain; loose; common very fine and few fine and medium roots; many very fine and fine irregular pores; 70 percent gravel and 5 percent cobbles; undersides of some gravel and cobbles coated with lime; slightly alkaline (pH 7.6).
TYPE LOCATION: Custer County, Idaho; about 20 miles southeast of Patterson, Idaho; about 50 feet south and 2,000 feet west from the northeast corner of section 16, T. 11 N., R. 25 E. Latitude - 44 degrees, 17 minutes, 28 seconds North; Longitude - 113 degrees, 28 minutes, 58 seconds West.
RANGE IN CHARACTERISTICS:
Mean annual soil temperature - 36 to 40 degrees F.
Mean summer soil temperature - 54 to 58 degrees F.
Mollic thickness range - 9 to 16 inches
Solum thickness range - 10 to 22 inches
Particle-size control section; clay averages - 6 to 14 percent
A horizons
Value - 2 or 3 moist
Bw horizon
Value - 4 to 6 dry, 3 or 4 moist
Chroma - 3 or 4
Texture - GRV-SL, GRV-L, CBX-SL
Rock fragments - 35 to 70 percent
2C horizons
Hue - 7.5YR or 10YR
Value - 5 to 7 dry, 4 to 6 moist
Texture - GRX-COS, GRX-LCOS, CBX-LS, CBX-LCOS
Rock fragments - 60 to 80 percent
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Firebox soils are on outwash fans and fan terraces. These soils formed in alluvium from quartzite. Slopes are 2 to 35 percent. Elevations are 6,000 to 7,000 feet. The soils are in cold semi-moist climate with an average annual precipitation of 13 to 16 inches. The average annual air temperature is 35 to 39 degrees F, average annual summer air temperature is 52 to 56 degrees F., and the frost-free period is 30 to 60 days.
GEOGRAPHICALLY ASSOCIATED SOILS: This is the Zeale soils. Zeale soils are loamy-skeletal.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderate over very rapid permeability.
USE AND VEGETATION: The soils are used for rangeland. Native vegetation is mainly threetip sagebrush and bluebunch wheatgrass.
DISTRIBUTION AND EXTENT: Central part of Idaho. The series is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Custer County, Idaho, 1999.
REMARKS: Diagnostic horizons and other features:
Mollic epipedon - 0 to 9 inches
Cambic horizon - 9 to 15 inches; the cambic is absent in some pedons.