LOCATION STRYKER                 MT

Established Series
Rev. JAL/KLS
11/2022

STRYKER SERIES


The Stryker series consists of very deep, somewhat poorly drained soils that formed in alluvium. These soils are on stream terraces. Slopes are 0 to 4 percent. Mean annual precipitation is about 510 mm, and mean annual air temperature is about 4 degrees C.

TAXONOMIC CLASS: Fine-silty, mixed, superactive, frigid Typic Haplustalfs

TYPICAL PEDON: Stryker silt loam, in forest (colors are for dry soil unless otherwise noted).

Oi--0 to 5 cm; forest litter of slightly decomposed needles and twigs.

E--5 to 13 cm; pinkish gray (7.5YR 7/2) silt loam, brown (7.5YR 5/2) moist; moderate thin platy structure; slightly hard, very friable, slightly sticky and slightly plastic; many fine and very fine roots; many very fine tubular and interstitial pores; slightly acid (pH 6.1); clear smooth boundary. (5 to 13 cm thick)

E/Bt--13 to 23 cm; E part (60 percent) pinkish gray (7.5YR 7/2) silt loam, brown (7.5YR 5/2) moist tongues; B part (40 percent) pinkish gray (7.5YR 7/2) silt loam, brown (7.5YR 5/4) moist; moderate medium subangular blocky structure; hard, friable, sticky and slightly plastic; common fine and very fine roots; many very fine tubular and interstitial pores; few faint brown (7.5YR 5/4) moist clay films on faces of peds; many light gray (10YR 7/1) silt skeletans on faces of peds; slightly acid (pH 6.1); clear smooth boundary. (8 to 25 cm thick)

Bt1--23 to 53 cm; pinkish gray (7.5YR 7/2) silty clay loam, brown (7.5YR 5/4) moist; moderate medium prismatic structure parting to moderate medium subangular blocky; hard, friable, sticky and plastic; common fine and very fine roots and few medium roots; many very fine tubular and interstitial pores; many distinct clay films of faces of peds; common light gray (10YR 7/1) silt skeletans on faces of peds; neutral (pH 6.6); clear smooth boundary. (20 to 38 cm thick)

Bt2--53 to 73 cm; pinkish gray (7.5YR 7/2) silt loam, brown (7.5YR 5/4) moist; weak medium prismatic structure parting to moderate medium subangular blocky; slightly hard, friable, sticky and slightly plastic; common fine and very fine roots and few medium roots; many very fine tubular and interstitial pores; common distinct clay films on faces of peds; slightly acid (pH 6.1); gradual wavy boundary. (10 to 33 cm thick)

Bt3--73 to 106 cm; pinkish gray (7.5YR 7/2) silt loam, brown (7.5YR 5/2) moist; few fine distinct mottles, strong brown (7.5YR 5/6) moist; weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few fine and very fine roots; many very fine tubular and interstitial pores; few distinct clay films on faces of peds; neutral (pH 6.6); gradual wavy boundary. (8 to 38 cm thick)

Bk--106 to 126 cm; pinkish gray (7.5YR 7/2) silt loam, brown (7.5YR 5/2) moist; common fine distinct mottles, strong brown (7.5YR 5/6) moist; weak medium and fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few fine and very fine roots; many very fine tubular and interstitial pores; disseminated lime; common fine seams and masses of lime; strongly effervescent; slightly alkaline (pH 7.4); clear smooth boundary. (10 to 25 cm thick)

2C--126 to 156 cm; light brownish gray (10YR 6/2) very gravelly sand, dark grayish brown (10YR 4/2) moist; single grain; loose; nonsticky and nonplastic; 50 percent pebbles; slightly effervescent; slightly alkaline (pH 7.4).

TYPE LOCATION: Lewis and Clark County, Montana, about 790 meters west and 670 meters north of the SE corner of sec. 23, T 14 N., R 9 W.

RANGE IN CHARACTERISTICS:
Soil temperature--5 to 7 degrees C
Moisture control section--10 to 30 cm
Depth to Bk horizon--50 to 100 cm
Depth to water table--61 to 107 cm

E horizon
Hue--7.5YR or 10YR
Value--5, 6, or 7 dry; 3, 4, or 5 moist
Chroma--1, 2, or 3
Texture--silt loam or silty clay loam
Clay content--18 to 30 percent
Reaction--pH 5.6 to 6.5

E/Bt horizon
Hue--E part 10YR or 7.5YR, Bt part 10YR or 7.5YR
Value--E part 6 or 7, Bt part 6 or 7 dry; E part 5 or 6, Bt part 4, 5, or 6 moist
Chroma--E part 2 or 3, Bt part 2, 3, or 4 moist
Clay content--18 to 27 percent
Reaction--pH 6.1 to 7.3

Bt horizons
Hue--10YR or 7.5YR
Value--6 or 7 dry, 5 or 6 moist
Chroma--2, 3, or 4
Texture--silty clay loam or silt loam
Clay content--25 to 35 percent
Reaction--pH 6.1 to 7.8

Bk horizon
Hue--10YR or 7.5YR
Value--6, 7, or 8 dry; 5 or 6 moist
Chroma--2, 3, or 4
Texture--silt loam or silty clay loam
Clay content--18 to 30 percent
Calcium carbonate equivalent--5 to 15 percent
Reaction--pH 7.4 to 8.4

2C horizon
Hue--10YR or 2.5Y
Value--5, 6, or 7 dry; 4, 5, or 6 moist
Chroma--2 or 3
Texture--sand or loamy sand
Clay content--0 to 5 percent
Rock fragment content--35 to 60 percent; 0 to 10 percent cobbles and stones, 35 to 50 percent pebbles
Reaction--pH 7.4 to 8.4

COMPETING SERIES:
Greenough (MT) - does not have a discontinuity of sandy-skeletal material; is well drained.
Half Moon (MT) - does not have a discontinuity of sandy skeletal material; is well drained.

GEOGRAPHIC SETTING:
Landform--stream terraces
Elevation--1375 to 1475 meters
Slope--0 to 4 percent
Parent material--alluvium
Climate--long, cold winters; moist springs; warm summers
Mean annual precipitation--380 to 610 mm
Mean annual air temperature--3 to 6 degrees C
Frost-free period--70 to 105 days

GEOGRAPHICALLY ASSOCIATED SOILS: None listed

DRAINAGE AND PERMEABILITY: Somewhat poorly drained; slow permeability

USE AND VEGETATION: Stryker soils are used mainly for woodland, understory grazing, and for wildlife habitat. The forest overstory consists of Ponderosa pine, Douglas fir, lodgepole pine, and Engelmann spruce. The forest understory is mainly pinegrass, common snowberry, heartleaf arnica, and mahonia.

DISTRIBUTION AND EXTENT: Stryker soils are of moderately extensive in mountain valleys of western Montana. MLRAs 43A, 44A and 44B

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Upper Flathead Valley Area, Montana, 1957. The type location was moved to Lewis and Clark County, Montana by correlation of the Soil Survey of Lewis and Clark County Area, Montana, 1991.

REMARKS: Soil Interpretations Records: MT0630
Diagnostic horizons and features recognized in this pedon are:
Albic horizon--5 to 13 cm (E horizon)
Glossic horizon--13 to 23 cm (E/Bt horizon)
Argillic horizon--23 to 106 cm with mottles below 73 cm (Bt1, Bt2, Bt3 horizons)
Secondary carbonate accumulations--106 to 126 cm (Bk horizon)
Lithologic discontinuity--126 to 156 cm (2C horizon)

Sawbuck soils have a frigid soil temperature regime and an ustic soil moisture regime with a typic subclass.

Converted to metric, updated formatting, and O horizons were updated to start at zero. Competing series section was not updated. 11/2022

Classification was changed to Typic Haplustalfs in 1997.


National Cooperative Soil Survey
U.S.A.