LOCATION MALM IDEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, frigid Xeric Haplocalcids
TYPICAL PEDON: Malm fine sandy loam, grassland. (Colors are for dry soil unless otherwise noted.)
A--0 to 3 inches; grayish brown (10YR 5/2) fine sandy loam, very dark grayish brown (10YR 3/2) moist; about 25 percent very dark gray basalt sand; weak very fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine roots; many very fine irregular pores; slightly alkaline (pH 7.4); abrupt wavy boundary. (0 to 5 inches thick)
AB--3 to 6 inches; brown (10YR 5/3) (grayish brown 10YR 5/2, crushed) fine sandy loam, dark grayish brown (10YR 4/2) moist; 25 percent very dark gray basalt sand; weak platy structure; soft, very friable, nonsticky and nonplastic; many very fine and fine roots; common very fine tubular pores; about 4 percent fine pebbles; slightly alkaline (pH 7.6); clear wavy boundary. (3 to 6 inches thick)
Bw--6 to 18 inches; pale brown (10YR 6/3) fine sandy loam, dark grayish brown (10YR 4/2) moist; weak medium and coarse subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine and fine roots; common very fine and fine tubular pores; about 4 percent fine pebbles; strongly effervescent; slightly alkaline (pH 7.8); gradual wavy boundary. (6 to 16 inches thick)
Bk1--18 to 23 inches; light gray (10YR 7/2) fine sandy loam, brown (10YR 5/3) moist; weak medium and fine subangular blocky structure; hard, friable, nonsticky and nonplastic; few very fine and fine roots; common very fine and fine tubular pores; few firm cicada krotovinas; 5 percent fine angular basaltic pebbles; violently effervescent; few fine spots, veins, and coatings of calcium carbonate; moderately alkaline (pH 8.4); clear wavy boundary. (4 to 10 inches thick)
Bk2--23 to 34 inches; light gray (10YR 7/2) fine sandy loam, brown (10YR 5/3) moist; massive; hard, friable, nonsticky and nonplastic; few very fine and fine roots; common very fine and fine tubular pores; few firm cicada krotovinas; 5 percent basaltic angular pebbles; violently effervescent; few spots and coatings of calcium carbonate; strongly alkaline (pH 8.6); abrupt wavy boundary. (6 to 11 inches thick)
2R--34 inches; very dark gray (10YR 3/1) basalt; calcium carbonate coating on surface and in pores and cracks.
TYPE LOCATION: Bingham County, Idaho; about 1 mile west and 1 mile north of Gardner; 2,390 feet south and 390 feet west of center of sec. 35, T. 1 S., R. 35 E.
RANGE IN CHARACTERISTICS:
Depth to the calcic horizon and secondary carbonates - 10 to 20 inches
Depth to bedrock - 20 to 40 inches
Mean annual soil temperature - 41 to 47 degrees F.
Mean summer soil temperature - 59 to 66 degrees F.
The moisture control section is dry for one-half to three-fourths of the time when the soil temperature is above 41 degrees F. 70 to 85 consecutive days.
Particle-size control section
Total clay content - 8 to 18 percent
Carbonate free clay 5 to 15 percent
Rock fragments - less than 30 percent, mostly angular basalt gravel, cobbles, and stones
A and AB horizons
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 2 or 3, dry or moist (dark color due in part to basaltic sand) This horizon may or may not be calcareous
Bw horizon
Value - 5 through 7 dry, 3 through 5 moist
Chroma - 2 or 3
Textures - FSL or SL
Bk horizons
Value - 6 to 8 dry, 4 through 6 moist
Chroma - 2 or 3
Texture - FSL, VFSL, SL, GR-FSL
Nodules - 0 to 10 percent hard or very hard
Calcium carbonate equivalent - 15 to 30 percent
Moderately to strongly alkaline
COMPETING SERIES: These are the Atomic, Holsine, Lariat, Lidy, Matheson, Nargon, Sparmo, and Voltage series. All of these soils except Lariat and Nargon are deep or very deep to bedrock. Lariat soils do not have a calcic horizon immediately above the bedrock. Nargon soils are loam or silt loam in the particle-size control section with 12 to 27 percent total clay and have a weighted average over 18 percent clay and have 10 to 18 percent carbonate clay.
GEOGRAPHIC SETTING: The soils are in level to rolling lava plains at elevations of 4,300 to 5,500 feet. Slopes range from 0 to 20 percent. The soils formed dominantly in moderately coarse textured eolian deposits, but the parent material includes alluvium and residuum weathered from the underlying basalt. The parent material is dominantly from basaltic, quartzitic and sedimentary rock sources. The climate is semiarid with dry summers. Average annual precipitation is 8 to 12 inches including 1.5 to 3 feet of snow. Average frost-free period is 70 to 125 days. Average annual temperature is 40 to 46 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Matheson soils and the Bondranch, Pancheri and Polatis soils. Bondranch soils have bedrock at a depth of less than 20 inches. Pancheri soils are more than 40 inches deep. Polatis soils are coarse-silty. These soils occur on nearby landscapes.
DRAINAGE AND PERMEABILITY: Well drained; slow to medium runoff; moderately rapid permeability.
USE AND VEGETATION: Used mainly for irrigated pasture, potatoes, and small grains, but some areas are used as rangeland. The principal native plants are needleandthread, streambank wheatgrass, Indian ricegrass, bitterbrush and bluebunch wheatgrass.
DISTRIBUTION AND EXTENT: The series is moderately extensive in the lava plains of southeastern Idaho.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Bingham County, Idaho, 1972.
REMARKS: Diagnostic horizons and features properties recognized in this pedon are:
Particle-size control section - 10 to 34 inches (part of the Bw and the Bk1 and Bk2 horizons); total clay content minus carbonate clay is less than 18 percent.
Ochric epipedon -
Calcic horizon - that zone from 18 to 34 inches (Bk1 and Bk2 horizons) secondary carbonates throughout and over 15 percent calcium carbonate.