LOCATION MACIVER MT
Established Series
Rev. ADI-KTS-EMM
05/2013
MACIVER SERIES
The Maciver series consists of very deep, well drained soils that formed in alluvium, colluvium or slide deposits derived from calcareous metamorphic and sedimentary rock sources. These soils are on fan remnants, alluvial fans, escarpments, hills, mountains or landslides. Slopes are 1 to 70 percent. Mean annual precipitation is about 20 inches, and mean annual air temperature is about 38 degrees F.
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive Calcic Argicryolls
TYPICAL PEDON: Maciver loam, in rangeland (colors are for dry soil unless otherwise noted).
A--0 to 7 inches; very dark gray (10YR 3/1) loam, black (10YR 2/1) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine, and few medium roots; few very fine and fine tubular pores; 10 percent gravel; neutral (pH 7.2); gradual wavy boundary. (5 to 12 inches thick)
Bt--7 to 11 inches; yellowish brown (10YR 5/4) very gravelly clay loam, dark yellowish brown (10YR 4/4) moist; weak fine subangular blocky structure; hard, friable, moderately sticky and moderately plastic; many very fine and fine roots; few very fine and fine tubular pores; few faint clay films on faces of peds; 35 percent gravel and 5 percent cobbles; neutral (pH 7.2); clear smooth boundary. (4 to 15 inches thick)
Bk1--11 to 23 inches; pale yellow (2.5Y 7/4) very gravelly clay loam, light olive brown (2.5Y 5/4) moist; weak fine subangular blocky structure; hard, friable, slightly sticky and moderately plastic; many very fine and fine roots; few very fine and fine tubular pores; 35 percent gravel and 5 percent cobbles; many medium segregated masses of calcium carbonate; violently effervescent; moderately alkaline (pH 8.2); gradual wavy boundary.
Bk2--23 to 30 inches; light yellowish brown (2.5Y 6/4) very gravely clay loam, light olive brown (2.5Y 5/4) moist; weak fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; few very fine and fine tubular pores; 35 percent gravel and 10 percent cobbles; many medium segregated masses of calcium carbonate; violent effervescent; moderately alkaline (pH 8.4); gradual wavy boundary.
Bk3--30 to 60 inches; pale brown (10YR 6/3) very gravely loam, yellowish brown (10YR 5/4) moist; weak coarse prismatic structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine roots; few very fine and fine tubular pores; 40 percent gravel and 15 percent cobbles; many medium segregated masses of calcium carbonate; violently effervescent; moderately alkaline (pH 8.2). (combined thickness of the Bk1, Bk2, Bk3 horizons - 33 to 49 inches)
TYPE LOCATION: Granite County, Montana; 1,150 feet south and 2,150 feet east of the NW corner of sec. 32, T. 5N, R. 14W.
RANGE IN CHARACTERISTICS:
Soil temperature - 36 to 41 degrees F.
Mollic epipedon thickness - 7 to 15 inches
Depth to top of argillic horizon - 5 to 12 inches
Depth to calcic horizon - 11 to 24 inches
A horizon
Value: 3 or 4 dry; 2 or 3 moist
Chroma: 1 or 2; dry or moist
Clay content: 15 to 27 percent
Texture: loam or sandy loam
Rock fragments: 0 to 45 percent--0 to 30 percent gravel, 0 to 30 cobbles, 0 to 5 percent stones or boulders
Reaction: pH 6.6 to 7.3 (pH 4.5 to 6.5 in impacted phase)
Bt horizon
Value: 4 to 6 dry; 3 to 5 moist
Chroma: 2 to 4; dry or moist
Texture: clay loam or silt loam
Clay content: 27 to 35 percent
Rock fragments: 35 to 60 percent--30 to 50 percent gravel, 0 to 15 percent cobbles, 0 to 3 percent stones
Reaction: pH 6.6 to 7.3
Bk horizons
Hue: 2.5Y or 10YR; dry or moist
Value: 6 to 8 dry; 5 or 6 moist
Chroma: 2 to 4; dry or moist
Texture: loam, sandy loam, clay loam or sandy clay loam
Clay content: 15 to 30 percent
Rock fragments: 40 to 70 percent--30 to 45 percent gravel, 3 to 15 percent cobbles
Calcium carbonate equivalent: 15 to 35 percent
Reaction: pH 7.9 to 8.4
COMPETING SERIES:
Brodie (WY) - have a lithologic discontinuity
Cavemountain (NV) - are moderately deep to a lithic contact
Daisypeak (MT) - are moderately deep to a lithic contact
Hodden (CO) - have a lithologic discontinuity
Hoodling (CO) - have peak precipitation during July and August
Latigo (ID) - have a xeric moisture regime
Nurkey (ID) - have a xeric moisture regime
Teeler (WY) - have hues redder than 10YR throughout
Wilhelm (WY) - have Btk horizons
GEOGRAPHIC SETTING:
Landform - fan remnants, alluvial fans, escarpments, hills, mountains or landslides
Elevation - 5,000 to 8,500 feet
Slope - 1 to 70 percent
Parent material - alluvium, colluvium or slide deposits derived from calcareous metamorphic and sedimentary rock sources
Climate - long, cold winters; cool, moist springs; short, cool summers
Mean annual precipitation - 15 to 22 inches with peak periods of precipitation occurring during the spring
Mean annual air temperature - 34 to 39 degrees F.
Frost-free period - 30 to 70 days
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Levengood,
Tiban, and
Tibson series. Levengood, Tiban, and Tibson soils lack an argillic horizon.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: Maciver soils are primarily used for rangeland. The potential native vegetation is mainly bluebunch wheatgrass, Idaho fescue, rough fescue, and Richardsons needlegrass. Some areas have widely spaced Douglas-fir and Rocky Mountain Juniper.
DISTRIBUTION AND EXTENT: Maciver soils are of moderate extent in southwestern Montana. MLRAs - 43B, 44B.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Granite County, Montana, 1997.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - from 0 to 7 inches (A horizon)
Argillic horizon - from 7 to 11 inches (Bt horizon)
Calcic horizon - from 11 to 60 inches (Bk1, Bk2, Bk3 horizons)
Particle-size control section - from 7 to 11 inches (Bt horizon)
Maciver soils have a cryic temperature regime and an ustic moisture regime.
ADDITIONAL DATA: Soil interpretation record - MT1476.
National Cooperative Soil Survey
U.S.A.