LOCATION JOPLIN MTEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, frigid Aridic Argiustolls
TYPICAL PEDON: Joplin loam, cultivated (colors are for dry soil unless otherwise noted).
Ap--0 to 4 inches; brown (10YR 5/3) clay loam, dark grayish brown (10YR 3/2) moist; weak fine granular structure; soft, friable, slightly sticky and slightly plastic; few very fine roots; common very fine discontinuous pores; neutral; clear smooth boundary. (3 to 7 inches thick)
Bt--4 to 9 inches; brown (10YR 5/3) clay loam, dark grayish brown (10YR 3/2) moist; moderate medium prismatic structure; slightly hard, firm, sticky and plastic; few very fine roots; common very fine discontinuous pores; common distinct clay films on faces of peds; neutral; gradual wavy boundary. (4 to 7 inches thick)
Bk1--9 to 16 inches; pale brown (10YR 6/3) clay loam, brown (10YR 5/3) moist; moderate medium subangular blocky structure; hard, firm, sticky and plastic; few very fine roots; common very fine discontinuous pores; common fine and medium masses of lime; strongly effervescent; moderately alkaline; gradual wavy boundary. (5 to 15 inches thick)
Bk2--16 to 26 inches; pale brown (10YR 6/3) clay loam, brown (10YR 5/3) moist; weak moderate subangular blocky structure; slightly hard, firm, sticky and plastic; few very fine roots; common very fine discontinuous pores; many fine and medium masses of lime; disseminated lime; strongly effervescent; moderately alkaline; gradual wavy boundary. (6 to 20 inches thick)
BC--26 to 60 inches; light brownish gray (10YR 6/2) clay loam, dark grayish brown (10YR 4/2) moist; massive; hard, firm, sticky and plastic; few very fine roots; common very fine discontinuous pores; disseminated lime; strongly effervescent; moderately alkaline.
TYPE LOCATION: Toole County, Montana; 1,600 feet north and 1,600 feet east of the SW corner of sec. 3, T. 32 N., R. 3 W.
RANGE IN CHARACTERISTICS:
Soil temperature - 42 to 47 degrees F.
Moisture control section - between 4 and 12 inches; dry in some part six-tenths or more of the cumulative days per year when the soil temperature at a depth of 20 inches is 41 degrees F or higher.
Mollic epipedon thickness - 7 to 10 inches thick.
Depth to secondary lime - 7 to 10 inches.
A Bky horizon is allowed.
Soil phases - cobbly, very cobbly, gravelly, calcareous.
Ap horizon - Hue: 10YR or 2.5Y
Chroma: 2 or 3
Texture: clay loam, loam, fine sandy loam, sandy loam
Clay content: 10 to 32 percent
Rock fragments: 0 to 60 percent--0 to 40 percent cobbles, 5 to 20 percent pebbles
Effervescence: none to violently
Calcium carbonate equivalent: 0 to 5 percent
EC: 0 to 4 mmhos/cm
Reaction: pH 6.6 to 8.4
Bt horizon - Hue: 10YR or 2.5Y
Value: 4 or 5 dry; 3 or 4 moist
Chroma: 2 or 3
Texture: loam or clay loam
Clay content: 25 to 35 percent
Rock fragments: 0 to 15 percent pebbles
EC: 0 to 4 mmhos/cm
Reaction: pH 6.6 to 8.4
Bk, Bky horizons - Hue: 10YR or 2.5Y
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2 or 3
Texture: loam or clay loam
Clay content: 18 to 32 percent
Rock fragments: 0 to 35 percent pebbles
Calcium carbonate equivalent - 5 to 15 percent
Gypsum: 0 to 5 percent
EC: 0 to 4 mmhos/cm
Reaction: pH 7.4 to 9.0
BC, Cy, or C horizon - Hue: 10YR or 2.5Y
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2 or 3
Texture: loam or clay loam
Clay content: 18 to 32 percent
Rock fragments: 0 to 35 percent pebbles
Moist bulk density: 1.6 to 1.8 gr/cm
Gypsum: 0 to 5 percent
EC: 2 to 8 mmhos/cm
Reaction: pH 7.4 to 9.0
COMPETING SERIES:
Assinniboine (MT) - has the base of the argillic horizon deeper than 10 inches; does not have high bulk density till above 60 inches.
Beavwan (MT) - has a discontinuity and have sandy-skeletal horizons above a depth of 40 inches.
Berlake (CO) - is noncalcareous to a depth of 40 inches or more.
Bostwick (CO) - is noncalcareous to a depth of 40 inches or more.
Cheeseman (CO) - has bedrock at a depth of 20 to 40 inches.
Crittenden (MT) - is sandy-skeletal below a depth of 25 inches.
Duffson (CO) - has bedrock at a depth of 20 to 40 inches.
Eapa (SD) - formed in alluvium or colluvium; does not have the high bulk density till above a depth of 60 inches.
Emlin (CO) - has a calcic horizon.
Evanot (CO) - has the base of the argillic horizon deeper than 10 inches; formed in eolian deposits; does not have high bulk density till above a depth of 60 inches.
Evanston (WY) - has the base of the argillic horizon deeper than 10 inches; does not have the high bulk density till above a depth of 60 inches.
Jarre (CO) - is noncalcareous to depths of 40 inches or more.
Kenilworth (MT) - has a discontinuity above a depth of 40 inches; has more than 45 percent fine sand and coarser above the discontinuity.
Kevin (MT) - has 35 to 45 percent clay in the argillic horizon.
Marmarth (ND) - has bedrock at a depth of 20 to 40 inches or more.
Morval (NM) - has a calcic horizon.
Notter (UT) - has a loamy-skeletal C horizon.
Nuley (MT) - has a calcic horizon and has sandy discontinuity.
Perrypark (CO) - is noncalcareous to depths of 40 inches or more.
Peyton (CO) - is noncalcareous to depths of 40 inches or more.
Reicess (WY) - has the base of the argillic horizon deeper than 24 inches.
Sugakool (WY) - has hues redder than 10YR in the argillic horizon; the base of the argillic horizon is deeper than 10 inches.
Telstad (MT) - the base of the argillic horizon is deeper than 10 inches.
Turret (CO) - is noncalcareous to a depth of 40 inches or more.
Udecide (MT) - has a paralithic contact of semiconsolidated sandstone at depths of 20 to 40 inches.
Varney (MT) - has a calcic horizon.
Villa Grove (CO) - has 5 to 20 percent exchangeable sodium in the surface and in the argillic horizon.
GEOGRAPHIC SETTING:
Landform - till plains; hills.
Elevation - 2,400 to 3,800 feet.
Slope- 0 to 25 percent.
Parent material - loamy continental glacial till.
Climate - long, cold, dry winters; moist springs; moist summers.
Mean annual precipitation - 10 to 14 inches.
Mean annual air temperature - 40 to 45 degrees F.
Frost-free period - 100 to 130 days.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability from the surface through the Bk horizons and slow in the underlying till.
USE AND VEGETATION: Joplin soils are used mainly for dryland farming for small grain and for range. Potential native vegetation is mainly western wheatgrass, needleandthread, blue grama, prairie junegrass, forbs, and shrubs.
DISTRIBUTION AND EXTENT: Joplin soils are extensive on the glaciated plains of northern Montana.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Reconnaissance of Northern Plains of Montana, 1929.
REMARKS: Soil interpretations records: MT0289, MT0680.
Diagnostic horizons and features recognized in this pedon are: mollic epipedon - from 7 to 9 inches (Ap, Bt horizons); argillic horizon - from 4 to 9 inches (Bt horizon); horizons of secondary carbonate accumulation - from 9 to 26 inches (Bk1, Bk2 horizons); high bulk density till - from 26 to 60 inches (BC horizon); particle-size control section - from the top of the argillic horizon to 40 inches. Joplin soils have a frigid temperature regime and an ustic moisture regime that borders on aridic.
ADDITIONAL DATA: Laboratory data S62-MT-101-1 and S62-MT-101-2.