LOCATION DORMONT                 PA+WV

Established Series
DJB/Rev. MDJ
12/2012

DORMONT SERIES

TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Oxyaquic Hapludalfs

TYPICAL PEDON: Dormont silt loam, in an idle field. (Colors are for moist soil.)

Ap--0 to 28 cm (0 to 11 inches); brown (10YR 4/3) silt loam; moderate fine granular structure; friable, slightly sticky, non-plastic; common very fine and fine roots throughout; 5 percent shale fragments; slightly acid; abrupt wavy boundary. (13 to 36 cm thick)

Bt1--28 to 53 cm (11 to 21 inches); strong brown (7.5YR 5/6) silt loam; strong medium subangular blocky structure; firm, slightly sticky, slightly plastic; few very fine roots between peds; 10 percent faint yellowish brown (10YR 5/4) clay films on faces of peds; 5 percent shale fragments; moderately acid; clear wavy boundary.

Bt2--53 to 79 cm (21 to 31 inches); reddish yellow (7.5YR 6/6) silty clay loam; moderate medium subangular blocky structure; firm, moderately sticky, moderately plastic; few very fine roots between peds; 30 percent distinct yellowish brown (10YR 5/6) clay films on faces of peds and linings of pores; 8 percent shale fragments; moderately acid; clear wavy boundary.

Bt3--79 to 117 cm (31 to 46 inches); pale brown (10YR 6/3) channery silty clay loam; strong medium and coarse subangular blocky structure; firm, moderately sticky, moderately plastic; 40 percent distinct clay films on faces of peds and linings of pores; 5 percent medium irregular black (5YR 2/1) manganese masses around rock fragments; common fine distinct irregular brownish yellow (10YR 6/6) masses of iron accumulation and many fine and medium distinct irregular gray (10YR 6/1) iron depletions; 18 percent shale fragments; moderately acid; gradual wavy boundary.

Bt4--117 to 157 cm (46 to 62 inches); light yellowish brown (10YR 6/4) very channery silty clay loam; strong medium and coarse subangular blocky structure; firm, slightly sticky, slightly plastic; 20 percent distinct clay films on faces of peds and linings of pores; 10 percent medium irregular black (5YR 2/1) manganese masses around rock fragments; many medium distinct irregular yellowish brown (10YR 5/6) masses of iron accumulation and many medium distinct irregular gray (10YR 6/1) iron depletions; 40 percent shale fragments; moderately acid; gradual wavy boundary. (Combined thickness of the Bt horizon is 63 to 129 cm)

BC--157 to 191 cm (62 to 75 inches); light yellowish brown (10YR 6/4) extremely channery silty clay loam; weak coarse subangular blocky structure; firm, slightly sticky, slightly plastic; 10 percent faint clay films on faces of peds; 5 percent medium irregular black (5YR 2/1) manganese masses around rock fragments; many fine distinct irregular strong brown (7.5YR 5/6) masses of iron accumulation and common fine distinct light gray (10YR 7/1) iron depletions; 80 percent shale fragments; moderately acid. (0 to 38 cm thick)

TYPE LOCATION:
State: Pennsylvania
County: Westmoreland
USGS Topographic Quadrangle: Donora, PA
Latitude: 40.171389 N (NAD 83)
Longitude: 79.793333 W (NAD 83)
Directions to Pedon: Rostraver Township, 0.75 miles SE of Sweeneys Crossroads, 530 feet NE of PA 51 in a field.

RANGE IN CHARACTERISTICS:
Depth to the top of the Argillic horizon: 13 to 36 cm (5 to 14 inches)
Depth to the base of the Argillic horizon: 102 to 167 cm (40 to 66 inches)
Solum Thickness: 91 to 191 cm (36 to 75 inches)
Depth Class: Deep and Very Deep
Depth to Bedrock: Greater than 102 cm (40 inches)
Depth to Seasonal High Water Table: 51 to 89 cm (20 to 35 inches), January through April
Rock Fragment content: 0 to 15 percent, by volume, in the A horizon, 2 to 15 percent in the upper part of the Bt horizon, 2 to 70 percent in the lower part of the Bt horizon, and 2 to 85 percent in the BC and/or C horizons
Soil Reaction: Very strongly acid through slightly acid in the upper part of the solum, strongly acid through slightly alkaline in the lower solum and substratum, except where limed

Range in Individual Horizons:
Ap or A horizon:
Color--hue of 7.5YR through 2.5Y; value of 3 through 5; and chroma of 2 through 4
Texture (fine-earth fraction)--silt loam or silty clay loam; 9 to 18 percent sand, 17 to 30 percent clay

E horizon: thin, where present

BA and/or BE horizon (where present):
Color--hue of 7.5YR through 2.5Y; value of 4 through 6; and chroma of 4 or 6
Texture (fine-earth fraction)--silt loam or silty clay loam; 8 to 20 percent sand, 20 to 34 percent clay

Bt horizon(upper part):
Color--hue of 7.5YR through 2.5Y; value of 4 through 6; and chroma of 4 or 6
Texture (fine-earth fraction)--silt loam or silty clay loam; 8 to 20 percent sand, 20 to 34 percent clay

Bt horizon(lower part):
Color--hue of 7.5YR through 5Y or neutral; value of 4 through 6; and chroma of 0 through 6
Texture (fine-earth fraction)--silt loam, silty clay loam, or silty clay; 7 to 20 percent sand, 20 to 50 percent clay
Redoximorphic depletions with chroma of 2 or less

BC and/or C horizon (where present):
Color--hue of 7.5YR through 5Y or neutral; value of 4 through 6; and chroma of 0 through 6
Texture (fine-earth fraction)--silt loam, silty clay loam, or silty clay; 4 to 15 percent sand, 20 to 45 percent clay

COMPETING SERIES:
Coggon soils--have a lithologic discontinuity and do not have more that 15 percent rock fragments
Hebron soils--have carbonates within the series control section
Nessel soils--have carbonates within the series control section

GEOGRAPHIC SETTING:
MLRA(s): 125 (Cumberland Plateau and Mountains), 126 (Central Allegheny Plateau), 127 (Eastern Allegheny Plateau and Mountains)
Landscape: Hills
Landform: Hill and hillslope
Hillslope Profile Position: Summit, shoulder or backslope
Geomorphic Component: Interfluve, side slope or head slope
Parent Material Origin: non-acid shale and siltstone and thin beds of limestone and sandstone
Parent Material Kind: Residuum
Slope: 0 to 50 percent
Elevation: 190 to 475 meters (620 to 1550 feet)
Frost-free period: 170 to 205 days
Mean Annual Air Temperature: 8 to 13 degrees C. (46 to 55 degrees F.)
Mean Annual Precipitation: 940 to 1220 mm (37 to 48 inches)

GEOGRAPHICALLY ASSOCIATED SOILS:
Clarksburg soils--occur on lower side slopes, head slopes and base slopes, and have a fragipan
Culleoka soils--occur on crests, nose slopes and side slopes with better drainage where bedrock is moderately deep
Guernsey soils--occur on similar positions of the landscape but where limestone predominates
Library soils--occur on less sloping interfluves, head slopes and base slopes where parent materials are dominantly limestone
Lowell soils--occur on crests, nose slopes and side slopes with better drainage where limestone predominates
Westmoreland soils--occur on crests, nose slopes and side slopes with better drainage

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage Class (Agricultural): Moderately well drained
Internal Free Water Occurrence: Thick (>100 cm), moderately deep (50-100 cm), and common (present 3-6 months)
Flooding Frequency and Duration: None
Ponding Frequency and Duration: None
Index Surface Runoff: Low through very high
Saturated Hydraulic Conductivity: Moderately low through high in the upper part, moderately low in the lower part
Shrink-Swell Potential: Low, medium or high

USE AND VEGETATION:
Major Uses: Pasture, woodland and some cropland
Dominant Vegetation: Where cultivated--mainly corn, soybeans and small grains; where wooded--chiefly mixed hardwoods, dominated by oak and maple

DISTRIBUTION AND EXTENT:
Distribution: Southwestern Pennsylvania and West Virginia
Extent: Extensive, about 470,000 acres at the time of this revision

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:
Ochric epipedon--the zone from 0 to 28 cm (Ap horizon)
Argillic horizon--the zone from 28 to 157 cm (Bt1, Bt2, Bt3, and Bt4 horizons)
Redoximorphic depletions with chroma of 2 or less--79 to 191 cm

This revision eliminates colluvium as a parent material for the Dormont series. Workers involved in recent Soil Survey updates believe this soil is mainly derived from residuum. Future MLRA update work on this series will include addressing Dormont where historically mapped in colluvial landform positions.

Previous revision: 08/2005-WRK,AWD,ART

________________________________________

---

National Cooperative Soil Survey
U.S.A.