LOCATION YAD                ID
Established Series
Rev. MEJ/ALH/RWL
06/2006

YAD SERIES


The Yad series consists of very deep, well drained soils with very slow permeability that formed in alluvium from lacustrine deposits over alluvium and colluvium from mixed lacustrine and igneous materials. Slopes range from 4 to 35 percent in foothills. The average annual precipitation is about 16 inches and the average annual temperature is about 49 degrees F.

TAXONOMIC CLASS: Fine, smectitic, mesic Chromic Haploxererts

TYPICAL PEDON: Yad clay loam -- on a 19 percent slightly concave southwest-facing slope at 3,460 feet elevation in rangeland. When described on September 18, 1995, the soil was dry to 22 inches and slightly moist below. (Colors are for air-dry soil unless otherwise noted.)

A--0 to 2 inches; brown (10YR 4/3) clay loam, dark brown (10YR 3/3) moist; moderate fine and medium granular structure; slightly hard, friable, moderately sticky and moderately plastic; common very fine and fine, few medium roots; many very fine and fine, few medium and coarse tubular pores; cracks 5mm to 4cm wide; neutral (pH 7.1); clear smooth boundary. (2 to 6 inches thick)

BA--2 to 6 inches; brown (10YR 5/3) clay loam, dark brown (10YR 3/3) moist; moderate coarse subangular blocky structure; very hard, friable, very sticky and very plastic; common very fine and fine, few medium roots; many very fine and fine, few medium and coarse tubular pores; cracks 5mm to 4cm wide; neutral (pH 7.2); clear smooth boundary. (3 to 9 inches thick)

Btss1--6 to 14 inches; pale brown (10YR 6/3) clay loam, brown (10YR 4/3) moist; weak coarse prismatic structure parting to strong medium and coarse subangular blocky; extremely hard, very firm, very sticky and very plastic; few very fine, fine, medium and coarse roots; common very fine and fine tubular pores; common distinct clay films on faces of peds and in pores; common intersecting slickensides; cracks 2mm to 2cm wide; few wedge shaped aggregates oriented 30 to 60 degrees from horizontal; 5 percent gravel; neutral (pH 7.1); clear smooth boundary. (4 to 13 inches thick)

Btss2--14 to 25 inches; pale brown (10YR 6/3) clay, brown (10YR 4/3) moist; strong medium and coarse prismatic structure; extremely hard, very firm, very sticky and very plastic; few very fine, fine, medium and coarse roots; common very fine and fine tubular pores; common prominent clay films on faces of peds and in pores; common intersecting slickensides; cracks 2mm to 2cm wide; few wedge shaped aggregates oriented 30 to 60 degrees from horizontal; 5 percent gravel; neutral (pH 7.2); clear smooth boundary. (8 to 24 inches thick)

2Bt1--25 to 41 inches; yellowish brown (10YR 5/4) clay loam, dark brown (7.5YR 3/4) moist; strong fine and medium subangular blocky structure; very hard, firm, moderately sticky and moderately plastic; few very fine, fine, medium and coarse roots; common very fine and fine tubular pores; common distinct clay films on faces of peds and in pores; 10 percent gravel; slightly alkaline (pH 7.4); clear smooth boundary. (10 to 19 inches thick)

2Bt2--41 to 52 inches; yellowish brown (10YR 5/4) gravelly sandy clay loam, brown (7.5YR 4/4) moist; moderate fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; few very fine, fine, medium and coarse roots; common very fine and fine tubular pores; few distinct clay films on faces of peds, in pores and bridging sand grains; 20 percent gravel; slightly alkaline (pH 7.4); clear wavy boundary. (5 to 13 inches thick)

2Bt3--52 to 60 inches; light yellowish brown (10YR 6/4) clay loam, brown (7.5YR 4/4) moist; moderate fine and medium subangular blocky structure; very hard, friable, moderately sticky and moderately plastic; few very fine, fine, medium and coarse roots; common very fine and fine tubular pores; common distinct clay films on faces of peds and in pores; 10 percent gravel; slightly alkaline (pH 7.4).

TYPE LOCATION: Ada County, Idaho; about 5 miles north and 1/2 mile west of Camels Back Park in Boise; 1,450 feet north and 100 feet east of the southwest corner of section 3, T.4 N., R.2 E.; USGS Boise North Quadrangle; Latitude - 43 degrees, 42 minutes, 34 seconds N. and Longitude - 116 degrees, 12 minutes, 46 seconds W.; NAD 83.

RANGE IN CHARACTERISTICS:
Epipedon thickness - 5 to 12 inches
Depth to discontinuity - 25 to 40 inches
Surface cracks - 5mm to 4cm wide; open from July through October in most years
Particle-size control section - 35 to 60 percent clay, 0 to 5 percent gravel
Moisture control section - dry 60 to 90 consecutive days following the summer solstice
Average annual soil temperature - 49 to 52 degrees F.

A and BA horizons
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 2 or 3 dry or moist
Clay content - 27 to 35 percent
Rock fragments - 0 to 5 percent cobbles
Cracks - 5mm to 5cm wide

Btss horizon
Value - 6 or 7 dry, 3 through 5 moist
Chroma - 2 through 4 dry or moist
Texture - CL or C
Clay content - 35 to 60 percent
Rock fragments - 0 to 5 percent gravel
Slickensides - few or common (intersecting)
Wedge shaped aggregates - few or common (oriented 30 to 60 degrees from horizontal)
Cracks - 1mm to 4cm wide

2Bt horizon
Hue - 7.5YR or 10YR
Value - 5 through 7 dry, 3 or 4 moist
Chroma - 3 or 4 dry or moist
Texture - SCL or CL
Clay content - 25 to 40 percent
Rock fragments - 5 to 20 percent gravel
Reaction - neutral or slightly alkaline

COMPETING SERIES: These are the Doubledia, Mchandy, Ravendale and Thorncreek series. Doubledia soils are 40 to 60 inches deep to a paralithic contact. Mchandy soils are 40 to 60 inches to an indurated duripan. Ravendale soils do not have Bt or Btss horizons, do not have a discontinuity above 40 inches and have carbonate accumulation at a depth of 40 to 60 inches. Thorncreek soils are 40 to 60 inches deep to a lithic contact.

GEOGRAPHIC SETTING: Yad soil are on hill footslopes, summits, shoulders and backslopes, structural benches, butte escarpment footslopes and landslides at elevations of 2,650 to 4,350 feet. Slopes range from 4 to 35 percent. These soils formed in alluvium from lacustrine deposits over alluvium and colluvium from mixed lacustrine and igneous materials. The average annual precipitation is 14 to 18 inches. The average annual temperature is 47 to 50 degrees F. The frost-free period is 110 to 140 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Aradaran, Ayette and Shafer soils. Aradaran soils have mollic epipedons more than 20 inches thick and are not cracked to the surface. Ayette soils are 40 to 60 inches deep to a paralithic contact and are not cracked to the surface. Shafer soils are 20 to 40 inches deep to a paralithic contact. These soils occur on the similar geomorphic positions.

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

USE AND VEGETATION: The Yad soils are used mainly for rangeland. Small areas are used for nonirrigated hayland/pasture. Native vegetation is bluebunch wheatgrass, xeric big sagebrush, Sandburg bluegrass and biscuitroot.

DISTRIBUTION AND EXTENT: West-central Idaho. MLRA 10. Yad soils are of small extent.

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

SERIES ESTABLISHED: Boise County Area, Idaho, Parts of Ada and Boise Counties, 2005.

REMARKS: Diagnostic horizons and features recognized in this pedon:
Ochric epipedon - zone from the surface to 6 inches (A and BA horizons)
Particle-size control section - zone from 10 to 40 inches
Cracks - 2 mm to 4 cm wide extending from the soil surface to 25 inches
Soil moisture regime - xeric


National Cooperative Soil Survey
U.S.A.