LOCATION GREENLEAF ID+OREstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, superactive, mesic Xeric Calciargids
TYPICAL PEDON: Greenleaf silt loam - cultivated. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 8 inches; light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; weak fine and very fine granular structure; hard, friable, slightly sticky and slightly plastic; common very fine roots; common very fine pores; part of the Bt has been mixed with the A by plowing; neutral (pH 7.0); abrupt smooth boundary. (0 to 13 inches thick)
Bt--8 to 13 inches; grayish brown (10YR 5/2) silty clay loam, brown (10YR 4/3) rubbed and moist; faces of peds coated with dark brown (10YR 3/3) moist; weak medium prismatic structure parting to moderate medium subangular blocky; hard, firm, moderately sticky and moderately plastic; common very fine and fine and few medium and coarse roots; common very fine and fine tubular pores; continuous clay films on the surfaces of peds and pores; common, fine soft manganese oxide concretions and staining on the peds; slightly alkaline (pH 7.7); abrupt wavy boundary. (3 to 7 inches thick)
Btk--13 to 17 inches; light gray (10YR 7/2) silt loam, dark grayish brown (10YR 4/2) moist; weak fine subangular blocky structure; hard, firm, slightly sticky and slightly plastic; many very fine and fine and few medium and coarse roots; many very fine tubular pores; few faint patchy clay films on surfaces of peds and pores; violently effervescent; moderately alkaline (pH 7.9); gradual smooth boundary. (2 to 5 inches thick)
Bk1--17 to 22 inches; light gray (10YR 8/2) silt loam, grayish brown (10YR 5/2) moist; moderate medium and thin platy structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine and few medium and coarse roots between plates; common very fine tubular pores; few fine manganese oxide concretions and coatings; violently effervescent; slightly alkaline (pH 7.7); clear smooth boundary. (5 to 15 inches thick)
Bk2--22 to 46 inches; light gray (10YR 7/2) silt laminated lake sediments, dark grayish brown (10YR 4/2) moist; strong medium and thin platy structure; slightly hard, firm and slightly plastic; many very fine and fine roots between laminae; few very fine tubular pores; few fine manganese oxide coatings mainly on laminae surfaces; violently effervescent and few lime veins in root channels; moderately alkaline (pH 7.9); lower 2 or 3 inches consist of moderate, thick and very thick laminae with many fine manganese oxide stains; abrupt smooth boundary. (10 to 30 inches thick)
C--46 to 90 inches; pale brown (10YR 6/3) silt lake sediments, dark grayish brown (10YR 4/2) moist; massive; slightly hard, friable; many soft fine manganese oxide concretions; slightly effervescent; moderately alkaline (pH 7.9); laminations more evident at about 68 inches.
TYPE LOCATION: Canyon County, Idaho; about 5 miles northwest of Caldwell; 1,340 feet north and 60 feet east of southwest corner of section 32, T. 5 N., R. 3 W.
RANGE IN CHARACTERISTICS:
Average annual soil temperature - 51 to 54 degrees F
Depth to laminated lake sediments (Bk2 horizon) - 12 to 40 inches
A horizon
Hue - 10YR or 2.5Y
Value - 5 through 7 dry, 3 through 5 moist
Chroma - 2 through 4 dry or moist
Reaction - neutral to moderately alkaline
Bt horizon
Hue - 10YR or 2.5Y
Value - 5 through 7 dry, 3 through 6 moist
Chroma - 2 through 4 dry or moist
Texture - L, SIL, SICL
Clay content - 22 to 30 percent
Reaction - slightly to moderately alkaline
Bk horizon
Calcium carbonate content - 15 to 40 percent
Other features - weak, thin silica crusts at the surface of one or more laminae in the C horizon.
COMPETING SERIES: These are the Larwood and Power series. Power soils have a solum 20 to 30 inches thick and lack the laminated silt lake sediments above 40 inches. Larwood soils have a mean annual soil temperature of 47 to 49 degrees F.
GEOGRAPHIC SETTING: Greenleaf soils are on level to strongly sloping, slightly to moderately dissected, low and medium terraces at elevations of 2,100 to 3,200 feet. The slopes are uniform and less than 2 percent but may range up to 30 percent. The soils formed in laminated, silty lacustrine deposits or old alluvium, though the upper part may be influenced by loess. The climate is semiarid, with dry summers. Average annual temperature is 49 to 52 degrees F and the average annual precipitation is 7 to 12 inches, including 0.5 to 2 feet of snowfall. The average frost-free season is 120 to 170 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bramwell, Nyssa, and Owyhee soils and the competing Power soils. Bramwell, Nyssa, and Owyhee soils lack argillic horizons. Bramwell soils are on bottomlands. The other soils are on landscape positions similar to Greenleaf soils.
DRAINAGE AND PERMEABILITY: Well-drained; slow or medium runoff; moderately slow permeability.
USE AND VEGETATION: Mostly irrigated cropland. The principal crops are alfalfa, sugar beets, corn, potatoes, small grains, onions, vegetable seed, and hops. The natural vegetation is Wyoming big sagebrush, Thurber needlegrass, and bluebunch wheatgrass.
DISTRIBUTION AND EXTENT: Southwestern Idaho and Southeastern Oregon; MLRA 11. The soils are moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Payette County, Idaho, 1971.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 8 inches (Ap horizon).
Argillic horizon - the zone from 8 to 17 inches (Bt horizons).
Calcic horizon - the zone from 13 to 46 inches (Btk, Bk1, and Bk2 horizons)
Particle-size control section - the zone from 8 to 17 inches (argillic horizon).