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

98 Soil Survey of
Chroma—2 to 6
Texture—the gravelly, very gravelly, or extremely
gravelly analogs of sand, loamy sand, coarse
sand, loamy coarse sand, or sandy loam
Content of gravel—15 to 70 percent
557A—Millstream silt loam, 0 to 2 percent
slopes
Setting
Landform: Outwash plains and stream terraces
Position on the landform: Footslopes
Slope range: 0 to 2 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
Millstream and similar soils: 85 percent
Dissimilar soils: 15 percent
Similar soils:
• soils that have a darker subsurface layer
• soils that have a lighter colored surface layer
• soils that contain more sand in the upper one-half of
the profile
• soils that contain less gravel in the lower part of the
profile
• soils that contain sandy and gravelly deposits at a
depth of less than 32 inches or more than 50 inches
Dissimilar soils:
• the poorly drained Dunham soils and the very
poorly drained Houghton and Palms soils in
depressions and drainageways
• the well drained Bowes and Waupecan soils in the
higher positions on the landform
Management
For general and detailed information about
managing this map unit, see the following sections in
Part II of this publication:
• “Agronomy” section
• “Forestland” section
• “Wildlife Habitat” section
• “Engineering” section
• “Soil Properties” section
Nappanee Series
Drainage class: Somewhat poorly drained
Permeability: Slow
Landform: Lake plains and moraines
Parent material: Lacustrine deposits
Slope range: 2 to 4 percent
Taxonomic classification: Fine, illitic, mesic Aeric
Epiaqualfs
Typical Pedon for MLRA 95B
Typical pedon of Nappanee silt loam, 2 to 4 percent
slopes, 1,380 feet south and 2,380 feet east of the
northwest corner of sec. 6, T. 44 N., R. 9 E.
Ap—0 to 8 inches; dark grayish brown (10YR 4/2) silt
loam, light brownish gray (10YR 6/2) dry; weak
very fine and fine granular structure; friable;
common very fine and few fine roots; common fine
dark yellowish brown (10YR 4/6) iron oxide
concretions throughout; neutral; abrupt smooth
boundary.
BE—8 to 11 inches; grayish brown (10YR 5/2) silty
clay loam; weak medium platy structure parting to
moderate very fine and fine granular; friable;
common very fine and few fine roots; many
distinct light gray (10YR 7/2 dry) clay depletions
on faces of peds; common fine distinct yellowish
brown (10YR 5/6) masses of iron accumulation in
the matrix; common fine faint gray (10YR 6/1) iron
depletions in the matrix; 1 percent gravel; neutral;
clear smooth boundary.
Bt1—11 to 17 inches; brown (10YR 4/3) silty clay;
moderate very fine subangular blocky structure;
firm; common very fine and few fine roots;
common distinct very dark grayish brown (10YR
3/2) organic coatings on faces of peds and in
pores; many distinct dark grayish brown (10YR
4/2) clay films on faces of peds; few fine and
medium black (10YR 2/1) iron and manganese
oxide concretions throughout; common fine
distinct yellowish brown (10YR 5/6) masses of iron
accumulation and grayish brown (2.5Y 5/2) iron
depletions in the matrix; 1 percent gravel; neutral;
clear smooth boundary.
Bt2—17 to 24 inches; brown (10YR 4/3) silty clay;
strong fine and medium subangular blocky
structure; firm; common very fine and few fine
roots; few distinct very dark grayish brown (10YR
3/2) organic coatings on faces of peds and in
pores; many distinct dark grayish brown (10YR
4/2) clay films on faces of peds; few fine black