LOCATION CHRISTIANA MD+DEEstablished Series
TAXONOMIC CLASS: Fine, kaolinitic, mesic Typic Paleudults
TYPICAL PEDON: Christiana silt loam - wooded
0i-- 1 to 0 inch; undecomposed leaves, twigs, needles.
A-- 0 to 2 inches; very dark gray (10YR 3/1) silt loam; weak fine granular structure; friable, many fine roots; very strongly acid; abrupt smooth boundary. (1 to 2 inches thick).
E-- 2 to 7 inches; yellowish red (5YR 5/6) silt loam; weak thin platy and weak fine granular structure; slightly hard, friable; many roots; very strongly acid; abrupt smooth boundary. (4 to 6 inches thick).
BE-- 7 to 14 inches; red (2.5YR 5/6) silty clay; moderate fine angular blocky structure; hard, friable, sticky, plastic; common roots; very strongly acid; gradual smooth boundary. (6 to 8 inches thick).
Bt1-- 14 to 30 inches; red (10R 4/6) clay; strong fine medium and coarse angular and subangular blocky structure; very hard, firm, sticky, plastic; few roots; many distinct clay films; very strongly acid; diffuse wavy boundary.
Bt2-- 30 to 60 inches; red (10R 4/6) clay; strong fine medium and coarse angular blocky structure; very hard, very firm, sticky, plastic; few roots in the upper part; many distinct red (10R 4/6) clay films in the upper part and reddish brown (2.5YR 4/4) clay films in the lower part; some black (N2/0) films on peds below 34 inches; very strongly acid; diffuse boundary. (Combined thickness of the Bt is 38 to 58 inches.)
C-- 60 to 120 inches; red (10R 4/6) clay; many fine prominent streaks and variegations of pinkish gray (7.5YR 7/2), some peds are pinkish gray (5YR 7/2); massive and weak very coarse angular blocky structure; very hard, firm, sticky, plastic; some thin clay films in cracks and on peds; few black (N2/0) iron and manganese stains; very strongly acid.
TYPE LOCATION: Prince Georges County, Maryland, on the Agricultural Research Center Farm.
RANGE IN CHARACTERISTICS: The thickness of the solum ranges from 53 to 84 inches. The solum of most pedons is free of rock fragments. Soil reaction ranges from extremely acid to strongly acid.
The A horizon has hue of 5YR to 10YR, value of 3 to 5 and chroma of 1 to 4. Texture is silt loam, fine sandy loam or loam; in eroded pedons, texture is clay loam, silty clay loam or clay.
The E horizon has hue of 5YR or 7.5YR, value of 4 to 6 and chroma of 4 to 8. Texture is silt loam, loam or fine sandy loam.
The Bt horizon has hue of 10R to 5YR, value of 3 to 5 and chroma of 4 to 8. Texture is silty clay, clay, or clay loam. Clay loam textures are limited to the upper part of the Bt1.
The C horizon has hue of 10R to 7.5YR, value of 4 to 8 and chroma of 2 to 8. It is variegated in most pedons. Texture is clay or silty clay.
COMPETING SERIES: The Dunmore series is the only soil in the same family. Dunmore soils have Bt horizons with 5YR hues, thinner sola and a lithic contact at 2 to 8 feet.
The Canmer, Dewey, Doniphan, Frederick, Fullerton, Henderson, Lugoff, Macedonia, Marlboro, Summerton, and Waynesboro series are similar soils in related families. Canmer, Doniphan, Frederick, and Macedonia soils have mixed mineralogy. The remaining soils have a thermic temperature regime.
GEOGRAPHIC SETTING: Christiana soils are on side slopes of the dissected upper part of the Northern Atlantic Coastal Plain. Slopes are complex and convex, and range from 0 to 50 percent. The soil formed in a loamy mantle over old cretaceous clays. The mean annual temperature ranges from 50 to 57 degrees F., and mean annual precipitation ranges from 40 to 46 inches. Frost-free days range from 170 to 210.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Muirkirk, Sunnyside, Keyport, Aura, Croom, Sassafras, and Beltsville soils. Muirkirk soils have sand or loamy sand to a depth of more than 20 inches, Sunnyside soils are fine-loamy with clayey textures at depths of more than 60 inches. Keyport soils are moderately well drained. Aura and Sassafras soils are fine loamy, Croom soils are loamy-skeletal and Beltsville soils are moderately well drained and have a fragipan.
DRAINAGE AND PERMEABILITY: Well drained. Surface runoff is rapid to very rapid. Permeability is moderately slow to slow.
USE AND VEGETATION: Little acreage is used for farming. The little that is farmed is in general crops such as corn. Extensive areas are in cut-over or second growth woodland. Wooded areas are white oak, red oak, black oak and Virginia Pine. The understory is dogwood, huckleberry, laurel and azalea. Some areas are urban and residential because this soil is in the Washington-Baltimore-Philadelphia corridor.
DISTRIBUTION AND EXTENT: Maryland, Delaware, District of Columbia and possibly northern Virginia. The soil is of moderate extent but locally important in expanding urban and suburban areas.
MLRA OFFICE RESPONSIBLE: Morgantown, West Virginia
SERIES ESTABLISHED: Christiana River Project, New Castle County, Delaware, 1940.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
a. Ochric epipedon - The zone from the surface to 2 inches (A horizon).
b. Argillic horizon - The zone from 14 to 60 inches (Bt1 and Bt2 horizons).
c. Paleudult feature - No part of the moisture control section is dry for as long as 90 consecutive days, the soil reaction is very strongly acid in the Bt2 horizon, the upper 20 inches of the Bt horizon has less than 10 percent weatherable minerals and the clay content does not decrease by more than 20 percent of its maximum by a depth of 60 inches.
TABULAR SERIES DATA:
SOI-5 Soil Name Slope Airtemp FrFr/Seas Precip Elevation MD0040 CHRISTIANA 0- 50 50- 57 170-210 40- 46 150- 350SOI-5 FloodL FloodH Watertable Kind Months Bedrock Hardness MD0040 NONE 6.0-6.0 - 60-60
SOI-5 Depth Texture 3-Inch No-10 Clay% -CEC- MD0040 0- 7 SIL FSL L 0- 0 80-100 10-26 - MD0040 0- 7 CL SICL C 0- 0 80-100 28-75 - MD0040 7-72 C SIC CL 0- 0 80-100 28-75 -
SOI-5 Depth -pH- O.M. Salin Permeab Shnk-Swll MD0040 0- 7 3.6- 5.0 1.-2. 0- 0 0.2- 2.0 LOW MD0040 0- 7 3.6- 5.0 .5-2. 0- 0 0.06- 0.6 MODERATE MD0040 7-72 3.6- 5.0 0.-.5 0- 0 0.06- 0.6 MODERATE