LOCATION HAVRE MT+ND SD UT WYEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, calcareous, frigid Aridic Ustifluvents
TYPICAL PEDON: Havre loam, in cropland (colors are for dry soil unless otherwise noted).
Ap--0 to 8 inches; grayish brown (10YR 5/2) loam, dark grayish brown (10YR 4/2) moist; weak granular structure; soft, very friable, slightly sticky and slightly plastic; many fine and very fine roots; strongly effervescent; moderately alkaline (pH 7.9); abrupt wavy boundary. (4 to 10 inches thick)
C1--8 to 36 inches; light brownish gray (2.5Y 6/2) loam consisting of thin strata of fine sandy loam, silt loam, and clay loam, dark grayish brown (2.5Y 4/2) moist; massive; slightly hard, very friable, slightly sticky and slightly plastic; common fine roots; common to many medium and fine pores; strongly effervescent; moderately alkaline (pH 8.2); clear wavy boundary. (18 to 30 inches thick)
C2--36 to 60 inches; light brownish gray (2.5Y 6/2) loam consisting of thin strata of clay loam, fine sandy loam, and silt loam, dark grayish brown (2.5Y 4/2) moist; massive; slightly hard, very friable, slightly sticky and nonplastic; few fine and very fine roots; common medium and fine pores; strongly effervescent; moderately alkaline (pH 8.2).
TYPE LOCATION: Blaine County, Montana; 1,050 feet north and 2,640 feet east of SW corner of sec. 33, T. 32 N., R. 23 E.
RANGE IN CHARACTERISTICS:
Soil temperature - 40 to 47 degrees F.
Moisture control section - between 4 and 12 inches; dry in all parts between four-tenths and five-tenths of the cumulative days per year when the soil temperature at a depth of 20 inches is 41 degrees F or higher.
Some pedons have a 2 to 5 inch horizon of weak prismatic or subangular blocky structure above a depth of 10 inches.
Soil phases - moderately wet, saline; flooded, PE greater than 31; cool; flooded, cool; moderately wet; clayey surface; flooded, clayey surface; clayey substratum; warm; saline.
Ap horizon - Hue: 10YR or 2.5Y
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2 or 3
Texture: loam, fine sandy loam, silt loam, clay loam, silty clay loam, clay or silty clay
Clay content: 10 to 55 percent
Calcium carbonate equivalent: 1 to 10 percent
Effervescence: none to strongly
EC: 0 to 8 mmhos/cm; saline phase is 4 to 16 mmhos/cm
SAR: 0 to 4
Reaction: pH 6.1 to 9.0
Some pedons have a thin A horizon that has a value of 4 dry and 3 moist and does not meet the requirement for a mollic epipedon after mixing to 7 inches.
C1 horizon - Hue: 10YR, 2.5Y, or 5Y
Value: 5 or 6 dry; 4 or 5 moist
Chroma: 2 or 3
Texture: loam, silt loam, sandy clay loam or clay loam which consist of strata of silt loam, fine sandy loam, very fine sandy loam, silty clay loam, and clay loam
Clay content: 18 to 35 percent
Calcium carbonate equivalent: 1 to 10 percent
Effervescence: slight or strongly
EC: 0 to 16 mmhos/cm; saline phase is 4 to 16 mmhos/cm
SAR: 0 to 13
Reaction: pH 7.4 to 9.0
Some pedons have 15 to 60 percent coarse fragments below a depth of 40 inches.
C2 horizon - Hue: 10YR, 2.5Y, or 5Y
Value: 5, 6 or 7 dry; 4 or 5 moist
Chroma: 2 or 3
Texture: loam, silt loam, sandy clay loam or clay loam which consist of strata of silt loam, fine sandy loam, very fine sandy loam, silty clay loam, and clay loam
Clay content: 18 to 35 percent
Calcium carbonate equivalent: 1 to 10 percent
Effervescence: slight or strongly
EC: 0 to 16 mmhos/cm; saline phase is 4 to 16 mmhos/cm
SAR: 0 to 13
Reaction: pH 7.4 to 9.0
COMPETING SERIES:
Bullhook (MT) - has an SAR greater than 13 below the surface 10 inches; has concentration of gypsum at depths of 5 to 15 inches.
GEOGRAPHIC SETTING:
Landform - flood plains; alluvial fans; stream terraces.
Elevation - 1,900 to 6,000 feet in Montana; ranges to 7,300 feet in Utah.
Slope- 0 to 6 percent.
Parent material - stratified calcareous loamy alluvium.
Climate - long, cold winters; moist springs; warm summers.
Mean annual precipitation - 10 to 16 inches, most of which falls during spring and the early part of summer.
Mean annual air temperature - 38 to 45 degrees F.
Frost-free period - 90 to 135 days.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Havre soils are mainly used for irrigated and nonirrigated crops. The potential native vegetation is bluebunch wheatgrass, western wheatgrass, green needlegrass, needleandthread, forbs, and shrubs.
DISTRIBUTION AND EXTENT: Havre soils are extensive in the plains area of Montana and in the states of Colorado, North Dakota, Nebraska, South Dakota, Utah, and Wyoming.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: St. Paul, Minnesota
SERIES ESTABLISHED: Milk River Area, Montana, 1928.
REMARKS: Soil interpretation records: MT0072, MT0181, MT0188, MT0256, MT0744, MT0745, MT0773, MT0777, MT0778, MT0816, MT0860, MT1009.
Diagnostic horizons and features recognized in this pedon are: ochric epipedon - from 0 to 8 inches (Ap horizon); stratified soil material (C1, C2 horizons); particle-size control section - from 10 inches to 40 inches (C1, C2 horizons). Havre soils have a frigid temperature regime and an aridic moisture regime bordering on ustic.
ADDITIONAL DATA: S51MT-85-3, S50MT-85-3, S51MT-85-6, S51MT-85-7, S51MT-43-3.