LOCATION PANMOD IDEstablished Series
TAXONOMIC CLASS: Coarse-silty, mixed, superactive, frigid Typic Durixerepts
TYPICAL PEDON: Panmod silt loam, cultivated. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 6 inches; brown (10YR 5/3) silt loam, very dark grayish brown (10YR 3/2) moist; moderate very fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; many very fine and few fine pores; slightly calcareous; moderately alkaline (pH 8.2); abrupt smooth boundary. (3 to 6 inches thick)
A--6 to 11 inches; brown (10YR 5/3) silt loam, dark brown (10YR 4/3) moist; moderate very fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; many very fine and few fine pores; slightly calcareous; moderately alkaline (pH 8.4); abrupt smooth boundary. (0 to 6 inches thick)
Bw1--11 to 17 inches; light brownish gray (10YR 6/2) silt loam, dark grayish brown (10YR 4/2) moist; weak medium and coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; many very fine and few fine pores; strongly calcareous; moderately alkaline (pH 8.4); clear wavy boundary. (0 to 10 inches thick)
Bw2--17 to 23 inches; light brownish gray (10YR 6/2) silt loam, grayish brown (10YR 5/2) moist; weak medium prismatic structure parting to weak coarse subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; many very fine and few fine pores; strongly calcareous; strongly alkaline (pH 8.6); clear wavy boundary. (0 to 10 inches thick)
Bw3--23 to 25 inches; light brownish gray (10YR 6/2) silt loam, grayish brown (10YR 5/2) moist; weak fine prismatic structure parting to weak medium subangular blocky; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine roots; many very fine pores; strongly calcareous; strongly alkaline (pH 8.6); abrupt wavy boundary. (0 to 6 inches thick)
2Bkqm--25 to 36 inches; pinkish white (7.5YR 8/2) duripan, pink (7.5YR 8/4) moist; strong very thick plates; extremely hard, extremely hard, extremely firm; many very fine roots matted on surface of plates and in cracks between plates; strongly calcareous; strongly alkaline (pH 8.6); abrupt wavy boundary. (3 to 15 inches thick)
2Bkq--36 to 50 inches; pinkish white (7.5YR 8/2) silt loam with 5 to 15 percent 2 to 5 cm. duripan chips, pinkish gray (7.5YR 7/2) moist; strong very fine granular structure; very hard, very firm, slightly sticky and slightly plastic; common very fine roots; strongly calcareous; strongly alkaline (pH 8.8); abrupt wavy boundary. (0 to 20 inches thick)
2Bkqm'--50 to 60 inches; pinkish white (7.5YR 8/2) duripan, pink (7.5YR 8/4) moist; strong thick plates; extremely hard, extremely firm; material similar to that in above layer between plates; strongly calcareous; strongly alkaline (pH 8.8); abrupt wavy boundary. (0 to 20 inches thick)
TYPE LOCATION: Madison County, Idaho; about 2 miles south and 4 miles east of Rexburg; about 480 feet east, 60 feet north of the center of sec. 7, T.5N., R.41E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature ranges from 38 degrees to 44 degrees F. The soils are usually moist, but are dry between depths of 4 and 12 inches for 45 to 70 consecutive days in mid and late summer. Depth to the duripan ranges from 20 to 40 inches. In some pedons the duripan is underlain by basalt.
The A horizon has value of 5 or 6 dry, and chroma of 2 or 3.
The Bw horizon has value of 5 through 7 dry and chroma of 2 or 3.
The 2Bkqm and 2Bkq horizons have hue of 10YR or 7.5YR, value of 7 or 8 dry, 6 through 8 moist, and chroma of 2 through 4.
COMPETING SERIES: These are the Burke, Minidoka and Stanfield series. These soils have a mesic soil temperature regime.
GEOGRAPHIC SETTING: Panmod soils are on basalt plains at elevations of 4,500 to 5,700 feet. Slopes range from 0 to 12 percent. The soils formed in deep loess. The mean annual precipitation is 10 to 14 inches, and the mean annual temperature is 37 degrees to 42 degrees F. The frost-free season is 70 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Rexburg and Ririe soils. These soils lack duripans.
DRAINAGE AND PERMEABILITY: Well drained; slow or moderate runoff; moderate permeability above the duripan and very slow in the duripan.
USE AND VEGETATION: Used for irrigated and dry cropland. Dryland crops are wheat and barley. Potatoes, wheat, barley and alfalfa are grown with irrigation.
DISTRIBUTION AND EXTENT: Southeastern Idaho. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Madison County, Idaho, 1977.
REMARKS: Classification changed 1/2000 from Typic Durochrepts to Typic Durixerepts based on revision of Soil Taxonomy.
Diagnostic horizons and features include:
Ochric epipedon
Cambic horizon - from 11 to 25 inches
Duripan - from 25 to 36 inches and from 50 to 60 inches
Particle-size control section - from 10 to 36 inches