LOCATION ENGETT IDEstablished Series
TAXONOMIC CLASS: Mixed, frigid Psammentic Haploxerolls
TYPICAL PEDON: Engett fine sand - on a north-facing slope of 1 percent under grass and shrubs at 5,120 feet in rangeland. (Colors are for dry soil unless otherwise noted. When described on June 11, 1981, the soil was moist below 4 inches.)
A1--0 to 6 inches; brown (10YR 4/3) fine sand, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; soft, very friable; common very fine and fine roots; few very fine irregular pores; neutral (pH 6.8); clear smooth boundary. (3 to 9 inches thick)
A2--6 to 20 inches; brown (10YR 4/3) fine sand, very dark grayish brown (10YR 3/2) moist; weak medium and fine subangular blocky structure; soft, very friable; common very fine and fine roots; few very fine irregular pores; neutral (pH 7.0); gradual smooth boundary. (4 to 14 inches)
Bw1-20 to 46 inches; brown (10YR 4/3) fine sand, very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky structure; soft, very friable; common very fine and fine roots; few very fine irregular pores; neutral (pH 7.0); gradual wavy boundary. (10 to 26 inches thick)
Bw2--46 to 60 inches; yellowish brown (10YR 5/4) loamy fine sand, dark grayish brown (10YR 4/2) moist; massive; soft, very friable; few very fine roots; neutral (pH 7.0).
TYPE LOCATION: Fremont County, Idaho; about 6 miles north of St. Anthony; 1,175 feet south, 725 feet west of the northeast corner of sec. 4, T.8N., R.41E.
RANGE IN CHARACTERISTICS:
Weighted average of percent clay in the control section - 2 to 8
Average annual soil temperature - 43 to 45 degrees F
Average summer soil temperature - 60 to 63 degrees F.
Depth to bedrock - greater than 40 inches
A horizon
Color value, dry - 3 or 4
value, moist - 2 or 3
chroma- 2 or 3, dry or moist
Reaction - neutral or mildly alkaline
B horizon
Color value, dry - 4 through 6
value, moist - 3 or 4
chroma- 2 through 4, dry or moist
texture - FS, S, LFS, CB-S
Coarse fragments - 0 to 20 percent
Reaction - neutral or mildly alkaline
Some pedons have an AB horizon.
COMPETING SERIES: These are the Blacksan(T), Contact and Haypress soils. Blacksan soils have bedrock at depths of less than 40 inches. Contact soils have 20 to 35 percent rock fragments. Haypress soils formed in residuum weathered from granitic rocks, have loamy coarse sand textures, and are moderately to slightly acid throughout.
GEOGRAPHIC SETTING: Engett soils are on nearly level to undulating basalt plains at elevations of 4,900 to 5,450 feet. Slopes are 1 to 6 percent. The soils formed in sandy eolian material from mixed sources influenced by slope alluvium. The average annual precipitation is 14 to 18 inches, and the average annual temperature is 41 to 43 degrees F. The frost-free period is 80 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Blacksan(T) soil, and the Eginbench, Juniperbute(T), Sandcreek(T), and St. Anthony (T) soils. Blacksan soils are on convex positions. Eginbench soils are on lower river terraces and have an induced water table. Juniperbute soils are adjacent to sand dunes and lack organic carbon to meet mollic criteria. Sandcreek soils are shallow and are adjacent to rock outcrops on convex positions. St. Anthony soils are on lower river terraces and are moderately deep to sand and gravel.
DRAINAGE AND PERMEABILITY: Somewhat excessively drained; runoff is slow; permeability is rapid.
USE AND VEGETATION: The soil is used principally for rangeland with minor areas of soils cropped to irrigated small grains and potatoes. Native vegetation is mainly antelope bitterbrush and needleandthread.
DISTRIBUTION AND EXTENT: These soils are moderately extensive in southeast Idaho.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Fremont County, Idaho.
REMARKS: Diagnostic horizons and features recognized in this soil are:
Mollic epipedon - from 0 to 20 inches (A1 and A2 horizons).
Particle size control section - from 10 to 40 inches (part of the A2 horizon and part of the Bw1 horizons).
Organic matter - greater than 1 percent based on lab data from another pedon