LOCATION FARROT IDEstablished Series
The Farrot series consists of moderately deep to bedrock, well drained
soils on foothills. They formed in alluvium and residuum from
intermediate intrusive rocks. Permeability is moderately slow. Slopes
are 0 to 60 percent. The average annual precipitation is about 14
inches and the average annual temperature is about 48 degrees F.
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Argixerolls
TYPICAL PEDON: Farrot coarse sandy loam - rangeland; on a 24 percent
east-facing slope at 3,840 feet elevation. When described on September
4, 1980, the Bt horizon was slightly moist. (Colors are for dry soil
unless otherwise noted.)
A1--0 to 4 inches; dark grayish brown (10YR 4/2) coarse sandy loam,
very dark brown (10YR 2/2) moist; moderate fine granular structure;
slightly hard, very friable, slightly sticky and slightly plastic; many
very fine roots; neutral (pH 7.0); abrupt smooth boundary. (3 to 7
inches thick)
A2--4 to 10 inches; grayish brown (10YR 5/2) coarse sandy loam,
very dark grayish brown (10YR 3/2) moist; weak medium subangular blocky
structure parting to moderate medium granular; hard, friable, slightly
sticky and slightly plastic; common fine roots; neutral (pH 6.8); clear
smooth boundary. (4 to 10 inches thick)
Bt1--10 to 15 inches; brown (10YR 5/3) sandy clay loam, dark brown
(10YR 3/3) moist; moderate medium subangular blocky structure; very
hard, firm, slightly sticky and slightly plastic; few very fine roots;
common moderately thick clay films on ped faces; 5 percent fine
pebbles; neutral (pH 6.7); gradual smooth boundary. (4 to 9 inches
thick)
Bt2--15 to 24 inches; light yellowish brown (10YR 6/4) sandy clay
loam, dark yellowish brown (10YR 4/4) moist; moderate medium subangular
blocky structure; very hard, very firm, slightly sticky and slightly
plastic; few very fine roots; many moderately thick clay films on ped
faces; 10 percent fine pebbles; mildly alkaline (pH 7.4); gradual wavy
boundary. (6 to 12 inches thick)
C--24 to 30 inches; light yellowish brown (10YR 6/4) very gravelly
coarse loam, dark yellowish brown (10YR 4/4) moist; massive; very hard,
very firm; very fine roots; few thin clay films; 40 percent pebbles;
mildly alkaline (pH 7.4); gradual irregular boundary. (1 to 7 inches
thick)
R--30 inches; slightly weathered quartz diorite.
TYPE LOCATION: Elmore County, Idaho; about 15 miles northwest of
Mountain Home; about 1,850 feet north and 1,900 feet east of the
southwest corner of section 7, T.1S., R.6E.
RANGE IN CHARACTERISTICS:
Average annual soil temperature - 47 to 53 degrees F
Mollic epipedon thickness - 10 to 18 inches
Depth to bedrock - 20 to 40 inches
A horizon
Value- 4 or 5 dry, 2 or 3 moist
Chroma- 2 or 3
Bt horizon
Hue- 10YR or 7.5YR
Value- 4 through 6 dry, 3 through 5 moist
Chroma- 3 or 4
Texture - SCL, CL, GR-SCL, GR-CL
Percent rock fragments - 5 to 25
Percent clay - 24 to 35
COMPETING SERIES: These are the Colma, Dragoon, Duzel, Facey, Foehlin,
Glenrose, Immiant (T), Ladd, Lobitos, Los Gatos, Mehlhorn, Morical,
Taneum, Tieton, Tweedy, and Yaxon series. Colma, Facey, Foehlin,
Glenrose, Ladd, Taneum, Tieton, and Yaxon soils are greater than 40
inches to bedrock. Morical soils have a paralithic contact at 20 to 40
inches. Dragoon soils have a loess mantle and a paralithic contact at
20 to 40 inches. Duzel soils have a average annual soil temperature of
53 to 59 degrees F and a Bt with a subhorizon containing more than 35
percent rock fragments. Lobitos soils have a average annual soil
temperature of 56 to 59 degrees F. Los Gatos soils have a average
annual soil temperature of 54 to 59 degrees F. Immiant and Mehlhorn
soils contain less than 35 percent sands in the control section.
Tweedy soils have a Bt with 5 to 15 percent mica and have a paralithic
contact at 20 to 40 inches.
GEOGRAPHIC SETTING: Farrot soils are on foothills at elevations of
3,600 to 5,000 feet. These soils formed in alluvium and residuum from
intermediate intrusive rocks. Slopes are 0 to 60 percent. The average
annual precipitation is 12 to 14 inches and the average annual
temperature is 46 to 50 degrees F. The frost-free season is 85 to 120
days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Haw and the competing
Ladd series. Haw soils are greater than 40 inches to bedrock. Haw
soils are generally on south and west-facing slopes. Ladd soils are on
positions similar to Farrot soils.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff;
moderately slow permeability.
USE AND VEGETATION: Used primarily for rangeland. The potential
natural plant community consists mainly of Xericensis big sagebrush,
antelope bitterbrush and bluebunch wheatgrass.
DISTRIBUTION AND EXTENT: Southwestern Idaho. The soils are moderately
extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Owyhee County, Idaho, 1975.
REMARKS: Formerly classified as a fine-loamy, mixed, mesic Calcic
Argixerolls. Farrot series is named after a creek.
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from 0 to 15 inches (the A and Bt horizons).
Argillic horizon - the zone from 10 to 24 inches (the Bt horizons).
Particle-size control section - the zone from 10 to 24 inches (the
argillic horizon).
National Cooperative Soil Survey