LOCATION LANKTREE           ID
Established Series
Rev. WJL/LMR/CLM
05/2001

LANKTREE SERIES


The Lanktree series consists of very deep, well drained soils on high terraces. They formed in alluvium dominantly from intermediate intrusive rocks. Permeability is slow. Slopes are 0 to 65 percent. The average annual precipitation is about 10 inches, and the average annual air temperature is about 50 degrees F.

TAXONOMIC CLASS: Fine, smectitic, mesic Xeric Haplargids

TYPICAL PEDON: Lanktree loam - rangeland. (Colors are for dry soil unless otherwise noted.)

A--0 to 0.5 inches; gray (10YR 5/1) loam, very dark gray (10YR 3/1) moist; weak thin platy structure that parts to weak very fine granular; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine pores; neutral (pH 6.6); abrupt wavy boundary. (0 to 1 inch thick)

E--0.5 to 8 inches; light brownish gray (10YR 6/2) loam, dark grayish brown (10YR 4/2) moist; lower part slightly lighter colored; weak very thin and thin platy structure that parts to weak very fine granular; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; common very fine pores; neutral (pH 6.8); abrupt wavy boundary. (5 to 13 inches thick)

Bt1--8 to 10 inches; brown (10YR 5/3) light clay loam, dark grayish brown (10YR 4/2) moist; moderate fine angular blocky structure; hard, firm, sticky and plastic; common very fine roots; common very fine pores; many faint clay films on faces of peds; thick layer of light gray (10YR 7/2) uncoated silt grains on surfaces of peds, grayish brown (10YR 5/2) moist; neutral (pH 7.3); abrupt wavy boundary. (1 to 3 inches thick)

Bt2--10 to 16 inches; pale brown (10YR 6/3) heavy clay loam, dark brown (10YR 4/3) moist; moderate medium prismatic structure that parts to moderate fine angular blocky; hard, firm, very sticky and very plastic; few very fine roots mostly on vertical surfaces; few very fine tubular pores; many prominent grayish brown (10YR 5/2) clay films on faces of peds, dark grayish brown (10YR 4/2) moist; mildly alkaline (pH 7.6); clear wavy boundary. (5 to 9 inches thick)

Btk1--16 to 22 inches; pale brown (10YR 6/3) heavy clay loam, dark brown (10YR 4/3) moist; moderate fine angular blocky structure; hard, firm, sticky and plastic; few very fine roots; few very fine tubular pores; many faint clay films on faces of peds; common medium splotches of calcium carbonate; mildly alkaline (pH 7.8); gradual wavy boundary. (4 to 8 inches thick)

Btk2--22 to 37 inches; pale brown (10YR 6/3) loam, brown (10YR 5/3) moist; weak fine subangular blocky structure; slightly hard, friable; slightly sticky and slightly plastic; few very fine roots; common very fine tubular pores; few faint clay films on faces of peds; common fine veins and splotches of calcium carbonate; moderately alkaline (pH 8.0); clear wavy boundary. (10 to 20 inches thick)

Bk--37 to 60 inches; light gray (10YR 7/2) loam, pale brown (10YR 6/3) moist; massive; slightly hard, friable; slightly sticky and slightly plastic; few very fine roots; common very fine tubular pores; strongly effervescent, many spots of calcium carbonate; moderately alkaline (pH 8.0); abrupt smooth boundary. (3 to 30 inches thick)

2C--60 to 80 inches; light gray (10YR 7/2) loamy sand, light brownish gray (10YR 6/2) moist; single grain; loose; slightly effervescent, mildly alkaline (pH 7.8)

TYPE LOCATION: Gem County, Idaho; about 8 miles southwest of Emmett; 400 feet south and 400 feet west of the northeast corner section 31, T. 6 N., R. 2 W.

RANGE IN CHARACTERISTICS:

Average annual soil temperature - 49 to 54 degrees F.
Depth to calcium carbonate - 15 to 30 inches

A and E horizons
Value - 5 through 7 dry, 3 through 5 moist
Chroma - 1 through 3
Reaction - slightly acid to mildly alkaline

Bt horizon
Value - 5 through 7 dry, 3 through 5 moist
Chroma - 2 through 4
Texture - SC, C, CL
Clay content - 35 to 45 percent
Reaction - neutral or mildly alkaline

Bk horizon
Reaction - mildly or moderately alkaline

COMPETING SERIES: These are the Buncelvoir (T), Farmell, Glasgow, Linkletter (T), Oppio, Risley, Schamp, and Trunk series. Buncelvoir and Farmell soils lack E horizons. Glasgow, Oppio, Risley, and Trunk soils have bedrock above 40 inches. Linkletter soils lack and E horizon and have a duripan at 40 to 60 inches. Schamp soils lack an E horizon and are strongly alkaline in the Bk horizon.

GEOGRAPHIC SETTING: Lanktree soils are in level to steep, dissected high terraces. Slopes range from 0 to 65 percent. Elevation ranges from 2,000 to 4,500 feet. The soils formed in the Idaho geologic formation consisting chiefly of unconsolidated sands, gravel or cobbles derived from granite or related igneous rocks. The average annual precipitation is 8 to 12 inches, including 1.5 to 3 feet of snowfall and the average annual temperature is 47 to 52 degrees F. Frost-free season is 115 to 150 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Elijah, Jenness, Purdam, Saralegui, and Vickery soils. They have less than 35 percent clay in their argillic horizons. Elijah, Purdam, and Vickery soils have a duripan. Jenness and Vickery soils lack an argillic horizon. Saralegui soils have less than 18 percent clay in the argillic horizon. These soils are on landscape positions similar to the Lanktree soil.

DRAINAGE AND PERMEABILITY: Well-drained; medium or rapid runoff; slow permeability.

USE AND VEGETATION: Used mainly for rangeland; some irrigated crops, such as alfalfa, pasture, clover, corn, and small grains. The natural vegetation is chiefly Wyoming big sagebrush, bluebunch wheatgrass, and Sandberg bluegrass.

DISTRIBUTION AND EXTENT: Southwestern Idaho and eastern Oregon, in the Payette section of the Columbia plateaus. The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Gem County, Idaho, 1962.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Ochric epipedon - the zone from 0 to 8 inches (A and E horizons).

Argillic horizon - the zone from 8 to 22 inches (Bt horizons).

Particle-size control section - the zone from 8 to 22 inches (argillic horizon).


National Cooperative Soil Survey
U.S.A.