Soil Survey of McHenry County, Illinois Part I - Soil Data Mart

102 Soil Survey of
firm; common very fine roots; few distinct dark
grayish brown (10YR 4/2) and brown (10YR 4/3)
clay films on faces of peds; few fine black (10YR
2/1) very weakly cemented iron and manganese
oxide concretions throughout; common fine
distinct dark yellowish brown (10YR 4/6) masses
of iron accumulation in the matrix; common fine
prominent grayish brown (2.5Y 5/2) iron depletions
in the matrix; 1 percent gravel; neutral; clear
smooth boundary.
2Bt4—26 to 31 inches; light olive brown (2.5Y 5/4)
silty clay loam; weak medium prismatic structure
parting to weak medium subangular blocky;
friable; common very fine roots; few distinct dark
grayish brown (2.5Y 4/2) clay films on faces of
peds and in pores; common fine black (10YR 2/1)
very weakly cemented iron and manganese oxide
concretions throughout; common fine prominent
dark yellowish brown (10YR 4/6) masses of iron
accumulation in the matrix; common fine distinct
grayish brown (2.5Y 5/2) iron depletions in the
matrix; 2 percent gravel; strongly effervescent;
slightly alkaline; clear smooth boundary.
2BC—31 to 37 inches; light olive brown (2.5Y 5/3) silty
clay loam; weak medium and coarse subangular
blocky structure; firm; common very fine roots; few
distinct dark grayish brown (2.5Y 4/2) clay films in
pores; few fine black (10YR 2/1) very weakly
cemented iron and manganese oxide concretions
throughout; few fine yellowish brown (10YR 5/8)
very weakly cemented iron oxide concretions
throughout; common fine and medium distinct light
olive brown (2.5Y 5/6) masses of iron
accumulation in the matrix; common fine and
medium faint grayish brown (2.5Y 5/2) iron
depletions in the matrix; 2 percent gravel; strongly
effervescent; moderately alkaline; gradual smooth
boundary.
2C—37 to 60 inches; light olive brown (2.5Y 5/3) silty
clay loam; massive; firm; common very fine roots;
common fine light gray (2.5Y 7/2) soft masses of
carbonates; common fine yellowish brown (10YR
5/8) very weakly cemented iron oxide concretions
throughout; few fine black (10YR 2/1) very weakly
cemented iron and manganese oxide concretions
throughout; common medium prominent yellowish
brown (10YR 5/6) masses of iron accumulation in
the matrix; common medium faint grayish brown
(2.5Y 5/2) iron depletions in the matrix; 3 percent
gravel; violently effervescent; moderately alkaline.
MLRA Series Range in Characteristics
Thickness of silty material: Less than 18 inches
Depth to carbonates: 14 to 40 inches
Thickness of the solum: 20 to 40 inches
Ap or A horizon:
Hue—10YR
Value—3 or 4
Chroma—1 to 3
Texture—silt loam or silty clay loam
E horizon (if it occurs):
Hue—10YR
Value—4 or 5
Chroma—2 or 3
Texture—silt loam or loam
Bt or 2Bt horizon:
Hue—10YR or 2.5Y
Value—4 to 6
Chroma—3 or 4
Texture—silty clay loam or silty clay
2C horizon:
Hue—10YR or 2.5Y
Value—4 or 5
Chroma—2 to 4
Texture—silty clay loam or clay loam
530B—Ozaukee silt loam, 2 to 4 percent
slopes
Setting
Landform: Moraines and till plains
Position on the landform: Summits, shoulders, and
backslopes
Slope range: 2 to 4 percent
A typical soil series description with range in
characteristics is included, in alphabetical order, in this
section. Additional information specific to this map
unit, such as horizon depth and textures, is available
in the “Soil Properties” section in Part II of this
publication.
Composition
Ozaukee and similar soils: 85 percent
Dissimilar soils: 15 percent
Similar soils:
• soils that have a darker surface layer
• soils that are moderately eroded
• soils that contain more sand and less clay in the
upper part of the profile
Dissimilar soils:
• the poorly drained Ashkum soils in depressions and
drainageways
• the somewhat poorly drained Beecher soils in the
lower positions on the landform