LOCATION AGERDELLY          ID
Established Series
Rev. LMR/CLM
02/97

AGERDELLY SERIES


The Agerdelly series consists of very deep well drained soils formed in volcanic tuff or siltstone on terraces. Slopes are 2 to 60 percent. Permeability is very slow. The average annual precipitation is about 13 inches, and the average air temperature is about 48 degrees F.

TAXONOMIC CLASS: Very-fine, smectitic, mesic Chromic Haploxererts

TYPICAL PEDON: Agerdelly clay - rangeland - on 30 percent slope at 2,150 feet elevation. Aspect south. (Colors are for dry unless otherwise noted. When described on April 7, 1976 the soil was moist.)

A1--0 to 4 inches; light brownish gray (2.5Y 6/2) clay, dark grayish brown (2.5Y 4/2) moist; strong fine and medium granular structure; very hard, friable, very sticky and very plastic; few very fine roots; many very fine irregular pores; 3 cm wide cracks; neutral (pH 7.2); abrupt smooth boundary. (1 to 4 inches thick)

A2--4 to 9 inches; light brownish gray (2.5Y 6/2) clay, dark grayish brown (2.5Y 4/2) moist; moderate medium prismatic structure; very hard, firm, very sticky and very plastic; few very fine roots; few very fine tubular pores; 2 cm wide cracks; neutral (pH 7.2); clear smooth boundary. (4 to 7 inches thick)

A3--9 to 22 inches; light brownish gray (2.5Y 6/2) clay, dark grayish brown (2.5Y 4/2) moist; strong fine and medium subangular blocky structure; very hard, very firm, very sticky and very plastic; few very fine roots; few very tubular pores; 2 cm wide cracks; many intersecting slickensides; mildly alkaline (pH 7.4); gradual smooth boundary. (12 to 20 inches thick)

A4--22 to 38 inches; light brownish gray (2.5Y 6/2) clay, dark grayish brown (2.5Y 4/2) moist; strong coarse prismatic structure; very hard, very firm, very sticky and very plastic; few very fine tubular pores; 1 cm wide cracks; common intersecting slickensides; moderately alkaline (pH 8.2); gradual smooth boundary. (6 to 10 inches thick)

Bk--38 to 60 inches; light brownish gray (2.5Y 6/2) clay, dark grayish brown (2.5Y 4/2) moist; common medium areas with pale yellow (10YR 7/4) colors; weak coarse prismatic structure parting to strong fine and medium subangular blocky; very hard, very firm, very sticky and very plastic; few very fine tubular pores; slightly effervescent; moderately alkaline (pH 8.2).

TYPE LOCATION: Washington County, Idaho; about 7 miles northwest of Weiser, about 2,300 feet west and 800 feet north of the southeast corner of section 18, T. 11 N., R. 6 W.

RANGE IN CHARACTERISTICS:

Cracks at least 1 cm wide from the surface to 20 inches or more are present from mid May to October.
Average annual soil temperature - 48 to 54 degrees F.
Depth to secondary lime - 30 to 44 inches
Depth to tuff or siltstone - more than 60 inches
Particle-size control section - 60 to 80 percent clay

A horizons
Hue - 10YR or 2.5Y
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 2 or 3 dry or moist

Bk horizon
Hue - 10YR or 2.5Y
Value - 6 or 7 dry, 4 or 5 moist
Chroma - 2 through 4 dry or moist
Calcium carbonate equivalent - 15 to 40 percent

COMPETING SERIES: These are the Ager, Beirman (T), and Tunnison (T) series. Ager soils have lime at a depth of less than 10 inches. Beirman soils have lime at 10 to 20 inches. Tunnison soils are 20 to 40 inches to bedrock.

GEOGRAPHIC SETTING: Agerdelly soils are on very gently sloping to steep dissected terraces at elevations of 2,100 to 4,500 feet. Slopes are 2 to 60 percent. The soils are formed from volcanic tuff or siltstone. The average annual precipitation is 12 to 14 inches and the average annual air temperature is 46 to 52 degrees F. The frost free season is 130 to 145 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bakeoven, Deshler, Deterson, Devnot, Glasgow, Lankbush, Lanktree, Payette, and Reywat series. Bakeoven soils are very shallow over basalt. Deshler and Glasgow soils are moderately deep over tuff. Deterson and Lanktree soils have fine textured particle-size control sections and lack slickensides. Devnot and Reywat are shallow over basalt. Lankbush soils have fine-loamy particle-size control sections. Bakeoven, Deshler, Devnot, Glasgow, and Reywat soils are on mountain slopes. Deterson, Lankbush, and Lanktree soils are on foothills and terraces. Payette soils have coarse-loamy particle-size control sections and are on high stream terraces.

DRAINAGE AND PERMEABILITY: Well drained; slow to very rapid runoff; very slow permeability.

USE AND VEGETATION: Used for rangeland, recreation, wildlife habitat and watershed. Vegetation is bluebunch wheatgrass, Sandberg and Nevada bluegrass, and big sagebrush. Present vegetation in many places is medusahead wildrye.

DISTRIBUTION AND EXTENT: West central Idaho. The soil is moderately extensive.

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

SERIES ESTABLISHED: Washington County, Idaho, 1992.

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

Ochric epipedon - surface to 38 inches (A1, A2, A3, and A4 horizons).

Moisture regime - xeric.

Particle-size control section - 10 to 40 inches (Part of the A3, the A4, and part of the Bk horizons).


National Cooperative Soil Survey
U.S.A.