LOCATION HEGLAR IDEstablished Series
The Heglar series consists of very deep, well-drained, moderately
permeable soils that formed in silty alluvium and loess. They are on
fan terraces and hillslopes and have slopes of 0 to 30 percent. The
average annual precipitation is about 14 inches and the average annual
temperature is about 46 degrees F.
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, mesic Typic Calcixerepts
TYPICAL PEDON: Heglar silt loam - range - on an 11 percent single
slope, west aspect, 4,950 feet elevation. (Colors are for air dry soil
unless otherwise stated. When described on Sept. 27, 1982, the soil was
dry below 5 inches.)
A--0 to 5 inches; pale brown (10YR 6/3) silt loam, dark brown (10YR
3/3) moist; weak fine and medium subangular blocky structure; slightly
hard, very friable, slightly sticky and slightly plastic; common very
fine and medium, few fine roots; many very fine irregular pores; mildly
alkaline (pH 7.8); clear smooth boundary. (3 to 6 inches thick)
Bw1--5 to 10 inches; pale brown (10YR 6/3) silt loam, dark brown
(10YR 3/3) moist; weak very coarse prismatic structure parting to weak
very coarse subangular blocky; hard, very friable, slightly sticky and
slightly plastic; common very fine, few fine roots; many very fine, few
fine tubular pores; moderately alkaline (pH 8.4); clear smooth
boundary. (6 to 12 inches thick)
Bw2--10 to 13 inches; very pale brown (10YR 7/3) silt loam, brown
(10YR 4/3) moist; weak medium and coarse subangular blocky structure;
hard, friable, slightly sticky and slightly plastic; common very fine
roots; many very fine tubular pores; moderately effervescent; 5 percent
firm and very firm when moist nodules; strongly alkaline (pH 8.8);
clear smooth boundary. (0 to 3 inches thick)
Bk1--13 to 17 inches; light gray (10YR 7/2) silt loam, pale brown
(10YR 6/3) moist; moderate coarse and very coarse platy structure;
hard, friable, slightly plastic; common very fine roots; common very
fine tubular pores; strongly effervescent (29 percent calcium
carbonate);strongly alkaline (pH 9.0); clear smooth boundary. (4 to 13
inches thick)
Bk2--17 to 27 inches; light gray (10YR 7/3) silt loam, pale brown
(10YR 6/3) moist; massive; hard, friable, slightly sticky and slightly
plastic; few very fine roots; many very fine tubular pores; violently
effervescent (30 percent calcium carbonate); 25 percent friable when
moist nodules; strongly alkaline (pH 9.0); gradual smooth boundary. (6
to 17 inches thick)
Bk3--27 to 36 inches; very pale brown (10YR 7/3) silt loam, brown
(10YR 5/3) moist; massive; slightly hard, very friable; few very fine
roots; common very fine tubular pores; violently effervescent (23
percent calcium carbonate); 20 percent hard, friable when moist,
nodules; strongly alkaline (pH 9.0); gradual smooth boundary. (7 to 15
inches thick)
Bk4--36 to 60 inches; pale brown (10YR 6/3) silt loam, brown (10YR
4/3) moist; massive; slightly hard, very friable; few very fine roots;
common very fine tubular pores; moderately effervescent (20 percent
calcium carbonate); violently effervescent, lime segregated in few fine
irregularly shaped seams and filaments; strongly alkaline (pH 9.0).
TYPE LOCATION: Cassia County, Idaho, about 3 miles east of Albion,
Idaho; about 200 feet east and 450 feet north of the southwest corner
of sec. 35, T. 11S., R. 25E.
RANGE IN CHARACTERISTICS:
Depth to calcic horizon - 10 to 20 inches
Thickness of calcic horizon - 10 to 22 inches
Calcium carbonate equivalent - 15 to 30 percent
Particle size control section - 8 to 15 percent clay
A horizon
Value- 5 or 6 dry, 3 or 4 moist
Chroma- 2 or 3
Reaction - mildly to moderately alkaline
Bw horizon
Value- 3 or 4 moist
Chroma- 2 or 3
Rock fragment content - 0 to 5 percent pebbles
Reaction - moderately to strongly alkaline
Bk horizons
Value- 6 through 8 dry, 4 through 7 moist
Chroma- 2 through 4
Texture - SI, SIL, or VFSL
Rock fragment content - 0 to 5 percent pebbles
Reaction - moderately to strongly alkaline
COMPETING SERIES: This is the Hillfield series. Hillfield soils formed
in lacustrine sediments. They have stratified C horizons with textures
ranging from fine sand to silty clay loam. They have laminated
sediments and lack hard nodules.
GEOGRAPHIC SETTING: Heglar soils are on fan terraces and hillslopes.
Slopes range from 0 to 30 percent. Elevation ranges from 4,400 to 5,600
feet. The soil formed in loess and silty alluvium. The average annual
precipitation is about 12 to 16 inches, the average annual air
temperature is about 45 to 48 degrees F., and the frost-free season is
100 to 125 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bahem, Declo, Rexburg,
and Watercanyon soils. Bahem and Declo soils are calcareous throughout
and have an aridic moisture regime. Rexburg soils have a mollic
epipedon and are frigid. Watercanyon soils are frigid. Bahem and Declo
soils are on fan terraces. Rexburg and Watercanyon soils are on uplands
and mountain sides above Heglar or have northerly aspects.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff;
moderate permeability.
USE AND VEGETATION: Heglar soils are used for range and dryland
crops. The natural vegetation is Wyoming big sagebrush and bluebunch
wheatgrass.
DISTRIBUTION AND EXTENT: This series is moderately extensive in
southern Idaho.
MLRA OFFICE RESPONSIBLE: Reno, Nevada
SERIES ESTABLISHED: Cassia County, Idaho, 1986.
REMARKS: NSSL sample S82 ID-031-003.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the surface to 10 inches (A and Bw
horizons)
Cambic horizon - The zone from 5 to 13 inches (Bw1 and Bw2 horizons)
Calcic horizon - The zone from 13 to 27 inches (Bk1 and Bk2 horizons)
Particle size control section - 10 to 40 inches (Bw2, Bk1, Bk2, Bk3 and
part of the Bk4 horizons)
National Cooperative Soil Survey