LOCATION LANKBUSH IDEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Xeric Haplargids
TYPICAL PEDON: Lankbush sandy loam -- on a southwest-facing slope at 2,680 feet elevation in rangeland. (Colors are for dry soil unless otherwise noted.)
A1--0 to 2 inches; light brownish gray (10YR 6/2) sandy loam, very dark grayish brown (10YR 3/2) moist; weak very fine and fine granular structure; soft, very friable; nonsticky and nonplastic; many very fine and fine roots; many very fine pores; neutral (pH 7.2); abrupt irregular boundary. (0 to 2 inches thick)
A2--2 to 14 inches; light brownish gray (10YR 6/2) sandy loam, very dark grayish brown (10YR 3/2) moist; weak thick and medium platy structure; slightly hard, very friable; slightly sticky and slightly plastic; many very fine and fine roots; common fine tubular pores; neutral (pH 7.2); clear smooth boundary. (2 to 12 inches thick)
Bt1--14 to 17 inches; light brownish gray (10YR 6/2) sandy clay loam, dark grayish brown (10YR 4/2) moist; weak medium prismatic structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and very fine roots; common fine tubular pores; few faint clay films on the faces of peds and in pores; slightly alkaline (pH 7.4); clear smooth boundary. (2 to 10 inches thick)
Bt2--17 to 27 inches; grayish brown (10YR 5/2) sandy clay loam, dark grayish brown (10YR 4/2) moist; moderate medium subangular blocky structure; hard, firm, moderately sticky and slightly plastic; few fine and very fine roots; many fine and very fine tubular pores; few distinct clay films on the vertical faces of peds and in pores; slightly alkaline (pH 7.7); clear smooth boundary. (5 to 15 inches thick)
Bt3--27 to 42 inches; pale brown (10YR 6/3) sandy clay loam, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; few very fine and fine roots; many very fine and fine tubular pores; few distinct dary grayish brown (10YR 4/2) clay films on the vertical faces of peds and in pores; slightly alkaline (pH 7.7); clear smooth boundary. (5 to 16 inches thick)
Bt4--42 to 50 inches; pale brown (10YR 6/3) sandy clay loam, brown (10YR 4/3) moist; weak medium subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; few very fine roots; many very fine and fine tubular pores; few faint clay films on the vertical faces of peds and in pores; slightly alkaline (pH 7.7); abrupt smooth boundary. (0 to 16 inches thick)
2C--50 to 65 inches; light gray (10YR 7/2) and very pale brown (10YR 7/3) micaceous, granitic sand; single grain; loose; moderately alkaline (pH 7.9); stratified with lenses of coarse sandy loam 0.5 to 1.5 inches thick, at intervals of 4 to 12 inches.
TYPE LOCATION: Canyon County, Idaho; about 6 miles northeast of Middleton; 1,240 feet west and 600 feet south of the northeast corner of section 13, T. 5 N., R. 2 W.; USGS Southwest Emmett Quadrangle; (Latitude - 43 degrees, 46 minutes, 40 seconds N. and Longitude - 116 degrees, 30 minutes, 17 seconds W.).
RANGE IN CHARACTERISTICS:
Average annual soil temperature - 47 to 55 degrees F.
Depth to secondary calcium carbonates - more than 40 inches
Depth to bedrock - more than 60 inches
Depth to lithologic discontinuity - 40 to 60 inches
Particle-size control section - 20 to 30 percent clay; 0 to 15 percent rock fragments
Moisture control section - moist less than 90 consecutive days when the soil temperature is greater than 47 degrees F.
A horizon
Hue - 10YR or 2.5Y
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 2 through 4 dry or moist
Gravel - 0 to 10 percent
Bt horizon
Value - 5 through 7 dry, 3 through 5 moist
Chroma - 2 through 4 dry or moist
Texture - SCL, CL, L
Clay content - 18 to 30 percent
Sand content - greater than 40 percent, dominantly medium sand or coarser
Gravel - 0 to 15 percent
Reaction - neutral to moderately alkaline
2C horizon
Value - 6 to 7 dry, 5 or 6 moist
Chroma - 2 through 6 dry or moist
Texture - COS, S, or LCOS with thin strata of COSL to LS
Clay content - 0 to 8 percent
Gravel - 0 to 25 percent
Effervescence - none to strongly
Reaction - slightly alkaline to strongly alkaline
COMPETING SERIES: These are the Abgese, Ackley, Barasco, Blacknest, Bluelight (T), Colbar, Eusbio (T), Greebrae, Hardtrigger, Harsan, Hoosegow, Hoye, Morfitt, Nosser, Shawave, Sidlake, Stiles (T), Turria, Windpoint and Zone series. Abgese, Ackley, Barasco, Blacknest, Hardtrigger, Harsan, Hoye, Shawave, Turria, Windypoint and Zone soils have secondary carbonates immediately below the argillic horizon, or within the upper 40 inches. Bluelight, Eusbio, Sidlake, and Stiles soils are moderately deep to a lithic or paralithic contact. Hoosegow soils have less than 40 percent sand which is dominantly fine sand in the particle-size control section. Greenbrae soils average 27 to 35 percent clay in the particle-size control section. Nosser soils have a particle-size
GEOGRAPHIC SETTING: Lankbush soils are in alluvial fans, fan skirts, old dissected terraces, footslopes, and dissected uplands at elevations of about 2,000 to 5,500 feet. The slopes range from 0 to 65 percent but are dominantly between 1 and 30 percent. These soils formed in loamy alluvium from igneous materials over sandy alluvium from granite. In places, there is some loess influence. Average annual precipitation is 8 to 12 inches, including 0.5 to 2 feet of snowfall. Average annual temperature is 45 to 53 degrees F. The frost-free period is 100 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Arbidge, Chuska, Elijah, Lanktree, Lolalita, Payette, Jenness and Udaho soils. Arbidge and Elijah soils occur on lower terraces, and are moderately deep to a hardpan. Chuska soils occur on higher terraces, and are shallow to a hardpan. Lanktree soils have more than 35 percent clay in the control section. Lolalita and Jenness soils lack an argillic horizon. Payette soils have a mollic epipedon. Udaho soils occur on sideslopes and breaks, lack argillic horizons, and are moderately deep to consolidated ash. Lanktree, Lolalita, Jenness and Payette soils are on landscape positions similar to the Lankbush soil.
DRAINAGE AND PERMEABILITY: Well drained, slow through very rapid runoff; moderately slow permeability.
USE AND VEGETATION: Lankbush soils are mainly used for rangeland. Natural vegetation is bluebunch wheatgrass, Thurber needlegrass, Indian ricegrass, Sandberg bluegrass, basin big sagebrush and Wyoming sagebrush. Some areas are cultivated and with irrigation produce small grains, alfalfa, corn, potatoes, sugar beets, hay and pasture.
DISTRIBUTION AND EXTENT: Southwestern and south-central Idaho; MLRA 11. 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 14 inches (A horizon)
Argillic horizon - the zone from 14 to 50 inches (Bt horizon)
Particle-size control section - the zone from 14 to 34 inches (upper 20 inches of the argillic)
Soil moisture regime - aridic bordering xeric
Ranges revised as per this 4/00 draft of the OSD are based on a review of the Ada, Canyon, Elmore, Jerome-Twin Falls, and Payette county soil surveys.
The Greenbrae series is similar to Lankbush and needs further investigation for adequate series differentia.