LOCATION PATTEE IDEstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, frigid Sodic Xeric Haplocambids
TYPICAL PEDON: Pattee silt loam-- on a 6 percent, south-facing slope at 4,500 feet elevation in rangeland. (Colors are for dry soil unless otherwise noted. When described on May 16, 1988, the soil was slightly moist to 10 inches and dry below this depth).
A--0 to 4 inches; light yellowish brown (10YR 6/4) silt loam, brown (10YR 4/3) moist; weak thin platy structure; soft, very friable, nonsticky and nonplastic; many very fine and fine and few medium roots; many very fine and fine irregular pores; slightly alkaline (pH 7.5); clear wavy boundary. (2 to 5 inches thick)
Bw1--4 to 10 inches; light yellowish brown (10YR 6/4) silt loam, brown (10YR 4/3) moist; moderate medium prismatic structure; slightly hard, friable, nonsticky and nonplastic; many very fine and fine and few medium roots; many very fine and fine irregular pores; 2 percent fine gravel; moderately alkaline (pH 7.9); clear wavy boundary.
Bw2--10 to 25 inches; light yellowish brown (10YR 6/4) silt loam, dark yellowish brown (10YR 4/4) moist; moderate coarse prismatic structure; slightly hard, friable, nonsticky and nonplastic; many very fine and fine and few medium roots; many very fine and fine irregular pores; 10 percent gravel; slightly alkaline (pH 7.7); clear wavy boundary. (Combined thickness of the Bw horizons is 14 to 28 inches)
Bkn1--25 to 30 inches; light yellowish brown (10YR 6/4) loam; brown (10YR 5/3) moist; moderate medium prismatic structure; slightly hard, friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine irregular pores; 2 percent gravel; lime coats 1mm thick on coarse fragments; strongly effervescent; moderately alkaline (pH 7.9); clear wavy boundary.
Bkn2--30 to 40 inches; very pale brown (10YR 7/3) loam, pale brown (10YR 6/3) moist; moderate coarse prismatic structure; slightly hard, friable, slightly sticky and nonplastic; few very fine and fine roots; many very fine and fine irregular pores; 5 percent gravel; lime coats 1 mm thick on coarse fragments; 5 percent weakly cemented cicada casts and nodules; violently effervescent; moderately alkaline (pH 8.2); clear wavy boundary.
Bkn3--40 to 49 inches; very pale brown (10YR 7/4) silt loam, brown (10YR 5/3) moist; massive; soft, very friable, slightly sticky and nonplastic; many very fine and fine irregular pores; 2 percent gravel; lime coats 1 mm thick on coarse fragments; violently effervescent; moderately alkaline (pH 7.9); clear wavy boundary. (Combined thickness of the Bk horizons is 15 to 45 inches)
2Bknz--49 to 60 inches; very pale brown (10YR 7/4) gravelly loam, yellowish brown (10YR 5/4) moist; massive; hard, firm, slightly sticky and slightly plastic; many very fine and fine irregular pores; 30 percent gravel; 10 percent filaments and soft masses of lime and salt crystals; lime coats 1 mm thick on coarse fragments; violently effervescent; slightly alkaline (pH 7.6).
TYPE LOCATION: Lemhi County, Idaho; about 5 miles southeast of Salmon, Idaho; about 2,100 feet south and about 2,100 feet east of the northwest corner of section 19, T. 21 N., R. 23 E. Latitude - 45 degrees, 09 minutes, 13 seconds North; Longitude - 113 degrees, 46 minutes, 57 seconds West.
RANGE IN CHARACTERISTICS:
Average annual soil temperature - 39 to 43 degrees F
Reaction of profile - slightly or moderately alkaline
Depth to secondary carbonates - 15 to 30 inches
Control section: percent clay - 10 to 18
coarse fragments - 2 to 10 percent
percent sand coarser than very fine sand - 5 to 15 percent
A horizon
value - 5 or 6 dry and 3 or 4 moist
chroma - 3 or 4 moist or dry
Bw horizon
value - 6 or 7 dry and 4 or 5 moist
chroma - 3 or 4 dry or moist
Texture - L, SIL
2Bkn horizon
value - 5 to 7 dry and 4 to 6 moist
chroma - 3 or 4 dry or moist
Texture - L, SIL
Coarse fragments - 2 to 10 percent
SAR - 13 to 20
Calcium carbonate - 5 to 15 percent
2Bknz horizon
Texture - GR-L, GR-SIL, GRV-SIL, GRV-L
Coarse fragments - 25 to 55 percent
SAR - 10 to 30
Calcium carbonate - 5 to 15 percent
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Pattee soils are on dissected stream terraces and foothills. These soils formed in alluvium. Slopes are 1 to 30 percent and elevations are 4,000 to 6,000 feet. The climate is cold and moist in winter and dry in summer. The average annual precipitation is 8 to 11 inches; average annual temperature is 38 to 42 degrees F.; and the frost-free period is 75 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dawtonia, Lacrol, Millhi and Perreau soils. Dawtonia soils are on ridges and foothills and have greater than 35 percent rock fragments in the control section. Lacrol soils are on foothills and have mollic epipedons. Millhi soils are on terraces and foothills and have greater than 35 percent clay in the control sections. Perreau soils are on terraces and foothills and have more than 18 percent clay in the control section.
DRAINAGE AND PERMEABILITY: Well drained. Slow and medium runoff. Moderate permeability.
USE AND VEGETATION: Irrigated cropland. Natural vegetation is mainly Wyoming big sagebrush, shadscale saltbrush and bluebunch wheatgrass.
DISTRIBUTION AND EXTENT: East-central Idaho. These soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Lemhi County, Idaho, 1999.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 4 inches (A horizon).
Cambic horizon - the zone from 4 to 25 inches (Bw1 and Bw2 horizons).
Particle-size control section - the zone from 10 to 40 inches (Bw2, Bk1, and Bk2 horizons).
ADDITIONAL DATA: Laboratory data S88ID-059-003