LOCATION MERTZ              PA+OH WV
Established Series
Rev. GDM-JRH
06/2001

MERTZ SERIES


The Mertz series consists of deep and very deep, well drained soils formed in colluvial or glacial material derived from limestone containing various amounts of chert fragments. Slopes range from 3 to 35 percent. Permeability is moderately slow. Mean annual precipitation is 42 inches. Mean annual temperature is 52 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, semiactive, mesic Typic Hapludults

TYPICAL PEDON: Mertz gravelly silt loam - cultivated. (Colors are for moist soil unless otherwise noted.)

Ap--0 to 9 inches; dark brown (10YR 3/3), very pale brown (10YR 7/3) when dry, gravelly silt loam; moderate medium granular structure; friable, slightly sticky, slightly plastic; 30 percent rock fragments; slightly acid; abrupt smooth boundary. (6 to 12 inches thick)

Bt1--9 to 16 inches; brown (7.5YR 4/4) very gravelly silty clay loam; weak medium subangular blocky structure; friable, sticky, plastic; common faint clay films in pores; 35 percent rock fragments; slightly acid; clear wavy boundary. (5 to 15 inches thick)

Bt2--16 to 26 inches; strong brown (7.5YR 4/4) very gravelly silty clay loam; weak medium subangular blocky structure; firm, sticky, plastic; common faint clay films on faces of peds and many in pores; 35 percent rock fragments; slightly acid; clear wavy boundary. (6 to 15 inches thick)

2Bt3--26 to 35 inches; strong brown (7.5YR 5/6) very gravelly loam; few coarse faint yellowish red (5YR 5/8) mottles; weak medium and fine subangular blocky structure; firm, sticky, plastic; many distinct clay films in pores and common on faces of peds; few black iron and manganese coatings on faces of peds and on fragments; 50 percent rock fragments; moderately acid; clear wavy boundary. (6 to 20 inches thick)

2Bt4--35 to 47 inches; strong brown (7.5YR 5/6) extremely gravelly clay loam; few coarse faint yellowish red (5YR 5/8) mottles; weak medium subangular blocky structure; firm, sticky, plastic; common faint clay films on faces of peds and distinct in pores; common black coatings on faces of peds and on fragments; 60 percent rock fragments; moderately acid; clear wavy boundary. (0 to 20 inches thick)

2Bt5--47 to 63 inches; strong brown (7.5YR 5/6) extremely gravelly clay loam; few coarse faint yellowish red (5YR 5/8) mottles; weak coarse subangular blocky structure; firm, slightly sticky, plastic; many distinct clay films in pores and on fragments; common black coatings on fragments; 70 percent rock fragments; strongly acid.

TYPE LOCATION: Juniata County, Pennsylvania; Monroe Township, 200 feet south of a point on Pa. Highway 35 that is 1.5 miles west of the Village of Richfield and 200 years east of a church.

RANGE IN CHARACTERISTICS: Solum thickness ranges from 40 to 80 inches. Depth to bedrock is more than 42 inches and dominantly exceeds 72 inches. Rock fragments are primarily chert but some are angular sandstone and shale, particularly in the lower horizons. Fragments in individual horizons of the soil range from 15 to 50 percent by volume in the upper part of the solum and from 15 to 80 percent in the lower part and C horizon. The weighted average rock fragment content of the top 20 inches of the Bt horizon is 35 to 50 percent by volume. The reaction ranges from neutral to strongly acid in the upper part of the solum and is strongly or very strongly acid below about 40 inches. Lithologic discontinuities in the solum are common but are absent in some pedons.

The Ap horizon has hue of 7.5YR or 10YR, value of 3 through 5, and chroma of 2 through 4; dry value is 6 or 7. Texture is silt loam or loam in the fine-earth fraction. Some pedons have a thin silt loam E horizon and others have a BA or BE horizon which is less than 10 inches thick.

The B horizon has hue of 5YR through 10YR, value of 4 through 6, and chroma of 4 through 8; the redder hues are normally in the lower solum. Texture is clay loam, silty clay loam, silt loam, or loam. The weighted average clay content in the top 20 inches of the Bt horizon ranges from 27 to 35 percent. Structure is weak or moderate, fine through coarse subangular blocky or blocky. Some pedons have coarse or very coarse prismatic structure. Consistence is firm or friable.

Some pedons have C horizons with color and texture similar to the B horizon.

COMPETING SERIES: The Croom, Elliber, Gainesboro, Hartleton, Irondale, Lew, and Pattenburg series are in the same family. Croom soils have gravelly very firm sandy clay loam Bt horizons and very gravelly loamy sand BC horizons. Elliber soils average more than 50 percent rock fragments and less than 27 percent clay in the top 20 inches of the Bt horizon. Gainesboro, Hartleton, and Irondale have sola less than 40 inches thick. Lew soils contain fragments of greenstone. Pattenburg soils have hue of 2.5YR or redder.

GEOGRAPHIC SETTING: Mertz soils occupy the gently sloping to steep upper and middle parts of chert ridges. Slope gradients range from about 3 to 35 percent. They formed in loamy cherty colluvium or glacial influenced material derived from limestone containing varying chert fragments. The climate is temperate and humid. Mean annual air temperature ranges from 47 to 57 degrees F., mean annual precipitation ranges from 36 to 48 inches, and the frost free season ranges from 150 to 210 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Elliber soils and the Evendale, Hagerstown, Kraemer, Morrison, and Vanderlip soils. All these soils, with the exception of Elliber, contain less than 35 percent rock fragments.

DRAINAGE AND PERMEABILITY: Well drained, runoff is medium or rapid, and permeability is moderately slow.

USE AND VEGETATION: Most of these soils are cleared and cultivated to general farm crops. Wooded areas are in mixed hardwoods.

DISTRIBUTION AND EXTENT: The ridge and valley sections of Pennsylvania, Maryland, and West Virginia. The series is of moderate extent. Pennsylvania has about 10,000 acres.

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

SERIES ESTABLISHED: Union County, Pennsylvania - 1940.

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

1. Ochric epipedon - the zone from the surface of the soil to a depth of about 9 inches (Ap horizon).

2. Argillic horizon - the zone from about 9 inches to a depth of 63 inches (Bt and 2Bt horizons).

ADDITIONAL DATA: Laboratory data are available on two pedons in Perry County, Pennsylvania - S70Pa50-10 and one pedon in Juniata County, Pennsylvania - S70Pa34-11.


National Cooperative Soil Survey
U.S.A.