LOCATION LIBRARY                 PA+VA

Established Series
Rev. AWD-WRK-ART
04/2025

LIBRARY SERIES

The Library series consists of deep and very deep, somewhat poorly drained soils formed in residuum of calcareous shale and thin bedded impure limestone. They are on uplands. Slope ranges from 0 to 25 percent. Saturated hydraulic conductivity is low. Mean annual precipitation is about 1000 millimeters and mean annual air temperature is about 10.7 degrees C.

TAXONOMIC CLASS: Fine, mixed, active, mesic Aeric Endoaqualfs

TYPICAL PEDON: Library silty clay loam 3 to 8 percent slopes, in an idle field. (colors are for moist soil unless otherwise noted).

Ap--0 to 20 inches; dark grayish brown (10YR 4/2) silty clay loam; weak fine granular structure; friable, slightly sticky and slightly plastic; many fine and very fine roots; slightly acid; abrupt smooth boundary. (5 to 11 inches thick)

Bt--20 to 33 centimeters; brown (7.5YR 5/4) silty clay; strong medium angular blocky structure; firm, moderately sticky and moderately plastic; common very fine roots; continuous distinct brown (10YR 5/3) clay films on faces of peds; common medium distinct grayish brown (10YR 5/2) iron depletions on faces of peds; 10 percent rock fragments; very strongly acid; clear wavy boundary.

Btg1--33 to 48 centimeters; grayish brown (10YR 5/2) silty clay; moderate medium prismatic structure parting to strong medium and coarse angular blocky; firm, moderately sticky and moderately plastic; few very fine roots; continuous prominent clay films on faces of peds and in pores; many fine distinct grayish brown (2.5Y 5/2) iron depletions and prominent olive (5Y 5/4) and distinct brown (7.5YR 4/4) masses of iron accumulation; very strongly acid; clear wavy boundary.

Btg2--48 to 64 centimeters; olive gray (5Y 5/2) silty clay; moderate coarse and medium prismatic structure parting to strong coarse angular blocky; firm, moderately sticky and moderately plastic; few very fine roots; continuous prominent clay films on faces of peds and in pores; many fine distinct olive brown (2.5Y 4/4) masses of iron accumulation and prominent gray (N 5/0) iron depletions; very strongly acid; clear wavy boundary. (Combined thickness of Bt the horizon is 38 to 140 centimeters.)

BCg--64 to 104 centimeters; olive gray (5Y 4/2) channery silty clay loam; moderate fine and medium platy structure; very firm, moderately sticky, and moderately plastic; common prominent clay films on faces of peds and rock fragments; thin black irregular bands of coal; 30 percent rock fragments; many distinct gray (5Y 5/1) iron depletions and distinct light olive brown (2.5Y 5/4) and prominent yellowish brown (10YR 5/6) masses of iron accumulation; strongly acid; abrupt irregular boundary. (0 to 50 centimeters thick)

C--104 to 152 centimeters; dark yellowish brown (10YR 4/4) and strong brown (7.5YR 5/6) very channery silty clay loam; weak medium platy structure; very firm, slightly sticky, moderately plastic; 40 percent rock fragments; faint olive brown (2.5Y 4/4) masses of iron accumulation and distinct grayish brown (2.5Y 5/2) iron depletions; neutral.

TYPE LOCATION: Allegheny County, Pennsylvania; North Fayette Township, 500 meters of intersection of routes 02033 and T362, and 200 meters northeast in field Latitude 40.435501, Longitude -80.183837 WGS 84.

RANGE IN CHARACTERISTICS: Solum thickness ranges from 76 to 165 centimeters. Depth to bedrock ranges from 101 to 202 centimeters. Rock fragments range from 0 to 20 percent in the Bt and Btg horizons, 0 to 30 percent in the BC horizon, and from 5 to 80 percent in the C horizon. Reaction is very strongly through neutral in the solum, strongly acid through mildly alkaline immediately below the solum and moderately acid to moderately alkaline at greater depths. Depth to carbonates ranges from 50 to 150 centimeters or more.

The Ap horizon has hue of 10YR to 2.5Y, value of 2 to 5, and chroma of 2 or 3. Dry values are 6 or higher. It is silt loam or silty clay loam in the fine-earth fraction.

Some pedons have thin BA or BE horizons with silty clay loam textures.

The Bt horizon is neutral or has hue of 7.5YR to 5Y, value of 4 to 6, and dominant chroma of 0 to 2. Some thin subhorizons have chroma of 3 or 4. Redoximorphic features are in shades of gray, grayish brown, reddish brown or yellowish brown. The Bt horizon is dominantly silty clay or clay in the fine-earth fraction with 45 to 60 percent clay. Some subhorizons can have textures of silty clay loam, but the control section average is 35 to 60 percent clay.

The BC and C horizon is neutral or has hue of 7.5YR to 5Y, value of 4 to 6, and chroma of 1 to 4. Some pedons have thin subhorizons with value of 2 or 3. It ranges from silt loam to clay in the fine-earth fraction.

COMPETING SERIES: Randolph and Parsippany soils are in the same family. Randolph has bedrock at 20 to 40 inches. Parsippany soils formed in lacustrine and old alluvial sediments and generally lack rock fragments.

GEOGRAPHIC SETTING: Library soils are on ridgetops, footslopes, backslopes, and benches. Slopes range from 0 to 25 percent, but are dominantly 0 to 8 percent. This soil formed in materials weathered from calcareous shale and thin bedded impure limestone. The mean annual precipitation ranges from 950 to 1125 millimeters; mean annual temperature ranges from 10.2 to 11.8 degrees C.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Clarksburg, Culleoka, Dormont, Faywood, Guernsey, Lowell, and Westmoreland soils. Faywood and Lowell soils do not have redoximorphic features. Culleoka, Westmoreland, Clarksburg, and Dormont soils have less than 35 percent clay in the control section Clarksburg soils also have a fragipan that Library soils lack. Dormont and Guernsey soils do not have redoximorphic features directly below the A horizon..

DRAINAGE AND PERMEABILITY: Somewhat poorly drained. The potential for surface runoff is negligible to very high. Saturated hydraulic conductivity is low.

USE AND VEGETATION: Largely in permanent hay, pasture and idle land. A few areas are cropped. Woodlands are mixed hardwoods.

DISTRIBUTION AND EXTENT: Southwestern Pennsylvania and Virginia. MLRA's 126 and 147. The series is of moderate extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Morgantown, West Virginia

SERIES ESTABLISHED: Allegheny County, Pennsylvania, 1973.

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

a. Ochric epipedon - the zone from the surface of the soil to a depth of about 20 centimeters (Ap horizon). b. Argillic horizon - the zone from 20 to 64 centimeters (Bt and Btg horizons).

ADDITIONAL DATA: Laboratory data is available on two pedons sampled in Allegheny County, Pennsylvania, S65--PA-02-5 and S65-PA-02-10.

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National Cooperative Soil Survey
U.S.A.