LOCATION HAW ID+UTEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Calciargidic Argixerolls
TYPICAL PEDON: Haw silt loam -- on a northwest-facing slope of 12 percent, in rangeland at 3,070 feet elevation. (Colors are for air-dry soil unless otherwise stated.)
A1--0 to 8 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak thin platy structure above 4 inches and weak very fine and fine granular structure below; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; common very fine pores; neutral (pH 6.8); clear wavy boundary. (4 to 9 inches thick)
A2--8 to 12 inches; grayish brown (10YR 5/2) silt loam, very dark grayish brown (10YR 3/2) moist; weak medium prismatic structure parting to weak medium subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; common very fine and fine tubular pores; neutral (pH 6.6); clear wavy boundary. (0 to 5 inches thick)
AB--12 to 15 inches; grayish brown (10YR 5/2) loam, dark brown (10YR 3/3) moist; weak medium prismatic structure parting to weak medium subangular blocky; hard, firm, slightly sticky and slightly plastic; few very fine roots; many very fine tubular pores; layer of bleached silt grains on peds; slightly acid (pH 6.4); clear wavy boundary. (0 to 4 inches thick)
Bt1--15 to 18 inches; grayish brown (10YR 5/2) loam, dark brown (10YR 3/3) moist; moderate medium prismatic structure parting to moderate medium subangular blocky; hard, firm, slightly sticky and slightly plastic; few fine roots; few faint clay films on faces of peds; slightly acid (pH 6.5); clear wavy boundary. (0 to 6 inches thick)
Bt2--18 to 25 inches; brown (10YR 5/3) clay loam, brown (10YR 4/3) moist; moderate fine prismatic structure parting to moderate coarse subangular blocky; very hard, very firm, moderately sticky and moderately plastic; few very fine roots; common very fine tubular pores; many distinct clay films on faces of peds; few bleached silt grains on peds; neutral (pH 6.7); gradual wavy boundary. (5 to 10 inches thick)
Bt3--25 to 30 inches; brown (10YR 5/3) heavy loam, brown (10YR 4/3) moist; weak coarse prismatic structure parting to weak coarse subangular blocky; very hard, firm, moderately sticky and moderately plastic; few very fine roots; few very fine pores; continuous faint clay films on faces of peds; neutral (pH 6.7); gradual wavy boundary. (0 to 6 inches thick)
Bk1--30 to 39 inches; brown (10YR 5/3) coarse sandy loam, brown (10YR 4/3) moist; massive; hard, friable, slightly sticky and slightly plastic; few very fine roots; few very fine tubular pores; slightly effervescent, few veins and spots of calcium carbonate; slightly alkaline (pH 7.7); gradual wavy boundary. (5 to 21 inches thick)
Bk2--39 to 49 inches; light yellowish brown (2.5Y 6/3) coarse sandy loam, olive brown (2.5Y 4/3) moist; massive; slightly hard, friable; few very fine roots; common very fine tubular pores; slightly effervescent; moderately alkaline (pH 7.9); clear irregular boundary. (3 to 18 inches thick)
C--49 to 75 inches; pale yellow (2.5Y 7/3) coarse sand, light yellowish brown (2.5Y 6/3) moist; single grain; loose; moderately alkaline (pH 8.3); clear irregular boundary.
TYPE LOCATION: Gem County, Idaho; about 4 miles southeast of Emmett; 1,600 feet south and 1,320 feet east of the northwest corner of section 27, T.6 N., R.1 W.; USGS Southeast Emmett Quadrangle; (43 degrees, 49 minutes, 54 seconds N. Latitude and 116 degrees, 26 minutes, 50 seconds W. Longitude.)
RANGE IN CHARACTERISTICS:
Average annual soil temperature - 47 to 53 degrees F.
Thickness of mollic epipedon - 9 to 20 inches
Depth to secondary calcium carbonates and base of argillic horizon - 22 to 38 inches
Depth to bedrock - more than 60 inches
Particle-size control section - 0 to 5 percent rock fragments (mainly gravel)
Moisture control section - moist less than 90 consecutive days when the soil temperature is greater than 47 degrees F.
C horizons are below 60 inches in some pedons
A horizon
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 1 through 3 dry or moist
Reaction - slightly acid to slightly alkaline
Bt horizon
Hue - 7.5YR or 10YR
Value - 5 or 6 dry, 3 through 5 moist
Chroma - 2 through 4 dry or moist
Texture - CL, SCL or L
Rock fragments (mainly gravel) - 0 to 5 percent
Clay content - 22 to 34 percent
Reaction - slightly acid to slightly alkaline
Bk horizon
Hue - 2.5Y or 10YR
Value - 5 through 8 dry, 4 through 7 moist
Chroma - 2 through 4 dry or moist
Texture - COSL, L or SL
Clay content - 10 to 25 percent
Rock fragments (mainly gravel) - 0 to 10 percent
Calcium carbonate equivalent - 1 to 15 percent
Reaction - slightly alkaline to strongly alkaline
COMPETING SERIES: These are the Axford, Babbington, Benwy, Bidwell, Brogan (T), Caliralls, Drybed, Polly and Zen series. Axford soils are deep to weathered bedrock and have average annual soil temperatures of 54 to 58 degrees F. Babbington soils are moderately well drained and are calcareous in the lower part of the argillic horizon. Benwy soils have a duripan at depths greater than 40 inches and average more than 5 percent rock fragments in the particle-size control section. Bidwell soils have secondary calcium carbonates in the lower part of the argillic horizon. Brogan soil shave a solum 20 to 40 inches thick over stratified loam and very fine sandy loam and are 15 to 25 inches to carbonates. Caliralls soils are more than 38 inches to the base of the argillic horizon and lack a substratum with coarse sand from lacustrine materials. Drybed soils are 10 to 20 inches deep to secondary calcium carbonates. Zen soils are moderately deep. Polly soils are 15 to 25 inches deep to the base of the argillic horizon and secondary calcium carbonates and are less than 5 inches to the top of the argillic horizon.
GEOGRAPHIC SETTING: Haw soils are level to steep on dissected terraces, foothills, alluvial fans, fan remnants and draw bottoms at elevations of 2,000 to 5,300 feet. Slopes range from 0 to 65 percent. These soils formed in coarse or moderately coarse textured, old unconsolidated or weakly consolidated lacustrine sediments derived mainly from intrusive igneous rocks and are commonly high in quartz, and in micaceous and feldspathic materials. A thin mantle of loessial material covers most of the sediments. The climate is cool and moist in the winter and hot and dry in the summer. Average annual precipitation ranges from 9 to 15 inches. Average annual temperature ranges from 45 to 51 degrees F. Frost-free period is 90 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Dishner, Lolalita, Montour and Van Dusen series. Dishner soils have bedrock within 20 inches of the surface and are on ridge tops. Lolalita soils are moderately coarse textured and lack a mollic epipedon and argillic horizon. Montour soils have more than 35 percent clay in the argillic horizon. Van Dusen soils have a mollic epipedon thicker than 20 inches and are on toeslopes. Dishner soils are on ridges. Lolalita, Montour and Van Dusen soils are on similar landscape positions.
DRAINAGE AND PERMEABILITY: Well drained; slow to very rapid runoff; moderately slow permeability.
USE AND VEGETATION: Haw soils are used mainly for rangeland and wildlife habitat. Some are used for orchards and irrigated cropland, pastureland and hayland. Crops grown include small grains, corn, potatoes and sugar beets. The dominant natural vegetation is bluebunch wheatgrass, Sandberg bluegrass, Wyoming big sagebrush, Thurber needlegrass, and Indian ricegrass.
DISTRIBUTION AND EXTENT: Southwestern Idaho and Utah. MLRA 11 and 25 in Idaho. Haw soils are extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Gem County Area, Idaho, 1962.
REMARKS: Diagnostic horizons and other features recognized in this pedon:
Mollic epipedon - zone 0 to 18 inches (A1, A2, AB and Bt1 horizons)
Argillic horizon and particle-size control section - zone 18 to 30 inches (Bt2 and Bt3 horizons)
Calcareous horizon - zone 30 to 49 inches (Bk1 and Bk2 horizons)
Soil moisture regime - aridic bordering xeric
These soils are drier than other Xerolls in the region under similar precipitation due to early runoff and extended period of high evapotranspiration.