LOCATION VOLLMER IDEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Argixerolls
TYPICAL PEDON: Vollmer silt loam -- on a 20 percent north-east facing slope at 3,190 feet elevation in pasture. When described on September 5, 1985, the soil was dry throughout. (Colors are for dry soil unless otherwise stated).
A1--0 to 3 inches; grayish brown (10YR 5/2) silt loam, black (10YR 2/1) moist; moderate medium subangular blocky structure parting to moderate very fine granular; hard, firm, sticky and slightly plastic; many very fine and fine roots; common very fine and fine tubular, and common fine irregular pores; 5 percent gravel; slightly acid (pH 6.2); clear smooth boundary.
A2--3 to 6 inches; grayish brown (10YR 5/2) silt loam, black (10YR 2/1) moist; weak medium subangular blocky structure; hard, firm; sticky and slightly plastic; many very fine and fine roots; common very fine and fine tubular pores; 5 percent gravel; neutral (pH 6.8); clear smooth boundary.
A3--6 to 12 inches; brown (10YR 5/3) silt loam, dark brown (10YR 3/3) moist; weak coarse subangular blocky structure; hard, firm, sticky and slightly plastic; common very fine and fine, few medium roots; common fine, few very fine tubular pores; common organic coatings on the faces of peds; 5 percent gravel; neutral (pH 6.6); clear smooth boundary. (combined thickness of the A horizons is 10 to 18 inches)
Bt1--12 to 28 inches; brown (10YR 5/3) silt loam, brown (10YR 4/3) moist; moderate medium prismatic structure parting to moderate medium subangular blocky; hard, friable, sticky and plastic; common very fine and fine, few medium roots; common very fine and fine tubular, few very fine and fine irregular pores; many faint discontinuous clay films lining pores and common faint patchy clay films on faces of peds; few 5mm thick clay bands; common distinct skeletans on faces of peds; 5 percent gravel; neutral (pH 6.6); clear wavy boundary. (4 to 18 inches thick)
Bt2--28 to 36 inches; pale brown (10YR 6/3) cobbly silt loam, brown (10YR 4/3) moist; moderate medium subangular blocky structure; hard, friable, sticky and plastic; common very fine, few fine and medium roots; common very fine and fine tubular pores; common moderately thick clay films lining pores; few 5mm thick clay bands; common distinct skeletans on faces of peds; 10 percent cobbles and 10 percent gravel; neutral (pH 6.6); abrupt wavy boundary. (4 to 16 inches thick)
2R--36 inches; basalt.
TYPE LOCATION: Lewis County, Idaho; about 2.5 miles east of Mohler; about 1,150 feet south and 1,300 feet east of the northwest corner of section 23, T. 34 N., R. 1 E.; USGS Mohler topographic quadrangle; Latitude - 46 degrees, 16 minutes, 43 seconds N.; Longitude - 116 degrees, 17 minutes, 59 seconds W.
RANGE IN CHARACTERISTICS:
Thickness of mollic epipedon - 10 to 18 inches Base saturation in all subhorizons below 10 inches - 75 to 95 percent Depth to bedrock - 20 to 40 inches Days dry in the moisture control section - 45 to 60 Average annual soil temperature - 47 to 50 degrees F
Particle-size control section (weighted averages) Clay content - 24 to 35 percent Coarse fragment content - 5 to 25 percent
A horizons Value - 4 or 5 dry, 2 or 3 moist Chroma, upper part - 1 or 2 moist Chroma, lower part - 2 or 3, dry or moist Reaction - slightly acid or neutral
Bt horizons Value - 4 through 6 dry, 3 or 4 moist Chroma - 3 or 4, dry or moist Texture - upper part: SIL, SICL lower part: CB-SIL, GR-CL, GR-SICL, CB-SICL Clay content - 24 to 35 percent Coarse fragment content - 0 to 35 percent Reaction - slightly acid or neutral
COMPETING SERIES: These are the Ahsahka(T), Buckbay(T), Colma, Dragnot (T), Duzel, Facey, Farrot, Foehlin, Hatspring(T), Immiant, Jauriga(T), Ladd, Lobitos, Los Gatos, Mehlhorn, Pittville(T), Taneum, Tieton, and Tweedy series. Ahsahka, Colma, Facey, Foehlin, Jauriga, Ladd, Pittville, Taneum, and Tieton soils are greater than 40 inches deep. Buckbay, Duzel, and Tweedy soils are moderately deep to a paralithic contact. Dragnot soils have 18 to 24 percent clay in the particle-size control section. Farrot soils are greater than 35 percent sand in the upper part of the argillic horizon. Hatspring soils are slightly alkaline or moderately alkaline in the Bt horizon, and are dry in the moisture control section for 90 to 105 days. Immiant soils are loam or clay loam in the upper Bt horizons and are dry for more than 60 days. Lobitos and Los Gatos soils have average annual soil temperatures warmer than 50 degrees F. Mehlhorn soils have hue of 5YR or 7.5YR in the Bt horizon.
GEOGRAPHIC SETTING: Vollmer soils are on hills on basalt plateaus. Slopes range from 3 to 25 percent. These soils formed in loess over material weathered from basalt. Elevation is 2,500 to 4,100 feet. Average annual precipitation is 21 to 24 inches, average annual temperature is 45 to 48 degrees F., and the frost free period is 100 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Uhlorn and Nez Perce series. Uhlorn soils are on hillsides and are very deep. Nez Perce soils are on hill summits and shoulders, and have an albic horizon, a clayey argillic horizon, and secondary carbonates.
DRAINAGE AND PERMEABILITY: Well drained; medium or rapid runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used for cropland and rangeland. Principle crops are wheat, barley, and peas. Native vegetation is mainly Idaho fescue, bluebunch wheatgrass, prairie junegrass, silky lupine, threeflower avens, and arrowleaf balsamroot.
DISTRIBUTION AND EXTENT: North central Idaho. This soil is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Lewis County, Idaho, 1995.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the surface to 12 inches (the A1, A2, and A3 horizons).
Argillic horizon - The zone from 12 to 36 inches (the Bt1 and Bt2 horizons).
Particle-size control section - The zone from 12 to 22 inches (the Bt1 and part of the Bt2 horizon).
Lithic contact - at 36 inches.