LOCATION SCHNOORSON ID+MTEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, active, calcareous, frigid Aeric Fluvaquents
TYPICAL PEDON: Schnoorson silty clay loam, cultivated; on a 0 percent slope at 1,750 feet elevation. When described on October 8, 1970, the soil was moist to 35 inches and saturated below. Pedon was redescribed on September 23, 1996. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 6 inches; light brownish gray (2.5Y 6/2) silty clay loam, dark grayish brown (2.5Y 4/2) moist; weak very fine granular structure; slightly hard, friable, slightly sticky and moderately plastic; many fine roots; many fine pores; strongly effervescent (calcium carbonate); slightly alkaline (pH 7.8); abrupt wavy boundary. (4 to 8 inches thick)
Cg1--6 to 20 inches; light gray (2.5Y 7/1) silty clay loam, grayish brown (2.5Y 5/2) moist; massive; very hard, firm, moderately sticky and moderately plastic; common fine roots; many fine pores; common coarse distinct yellowish brown (10YR 5/4) and brown (7.5YR 5/4) redox concentrations; strongly effervescent (calcium carbonate); slightly alkaline (pH 7.8); clear wavy boundary. (11 to 18 inches thick)
Cg2--20 to 31 inches; light gray (5Y 7/1) silty clay loam, dark gray (5Y 4/1) moist; massive; very hard, firm, moderately sticky and moderately plastic; many fine and medium pores; common coarse prominent brown (7.5YR 5/4) and light reddish brown (2.5YR 6/3) redox concentrations; slightly alkaline (pH 7.5); clear wavy boundary. (9 to 14 inches thick)
Cg3--31 to 40 inches; light gray (2.5Y 7/1) silty clay loam, dark gray (2.5Y 4/1) moist; massive; very hard, firm, moderately sticky and moderately plastic; many fine and medium pores; common coarse prominent brown (7.5YR 5/4) and reddish brown (2.5YR 4/3) redox concentrations; slightly alkaline (pH 7.5); clear wavy boundary. (8 to 15 inches thick)
Cg4--40 to 65 inches; light gray (2.5Y 7/1) silty clay, bluish gray (5B 5/1) moist; massive; very hard, very firm, very sticky and very plastic; few fine and medium pores; common coarse prominent brown (7.5YR 5/4) redox concentrations; slightly alkaline (pH 7.5).
TYPE LOCATION: Boundary County, Idaho; about 2 miles west of Bonners Ferry and south of the Kootenai River; about 1,140 feet south and 2,440 feet east of the northwest corner of sec. 29, T. 62 N., R. 1 E.; Latitude - 48 degrees, 41 minutes, 59 seconds North; Longitude - 116 degrees, 21 minutes, 46 seconds West; USGS Bonners Ferry Quadrangle.
RANGE IN CHARACTERISTICS:
Average annual soil temperature - 45 to 47 degrees F.
Average summer soil temperature - 58 to 63 degrees F.
Depth to high water table - 0 to 18 inches undrained (December to July), 18 to 36 inches drained (December to June)
Thin buried A horizons - present in some pedons
Thin organic layers present in some pedons
Snail shells - common in upper part of profile
Cracks - 1/2 to 2 inches wide extending from surface to a depth of 24 to 36 inches when dry
Ap horizon
Hue - 2.5Y or 10YR
Value - 6 or 7 dry, 4 or 5 moist
Chroma - 1 or 2 dry or moist
Texture - SIL, SICL
Clay content - 18 to 35 percent
Effervescence - slightly to violently (calcium carbonate)
CaCO3 equivalent - 5 to 15 percent
Reaction - slightly alkaline or moderately alkaline
Cg horizons
Value - 6 or 7 dry, 4 or 5 moist
Chroma - 1 or 2 dry or moist
Redoximorphic features - common to many, chroma 3 to 6 dry or moist
Texture - SICL, stratified SICL and SIL, and SIC below 40 inches
Clay content - 20 to 35 percent in upper part; 20 to 50 percent in lower part
Effervescence - none to violently (calcium carbonate)
CaCO3 equivalent - 0 to 15 percent
Reaction - slightly or moderately alkaline
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Schnoorson soils are in basins and swales on flood plains. They formed in alluvium. Slopes range from 0 to 2 percent. Elevation ranges from 1,700 to 2,000 feet. The summers are usually dry and warm and winters are cold and wet. Average annual precipitation is 20 to 28 inches and average annual air temperature is 43 to 46 degrees F. The average frost-free period is 100 to 140 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the DeVoignes, Farnhamton, and Ritz soils. DeVoignes soils are in depressions on flood plains and have a histic epipedon. Farnhamton and Ritz soils are on higher positions on flood plains and have coarse-silty control sections.
DRAINAGE AND PERMEABILITY: Natural drainage is poor. Artificial drainage is now used in most of the cultivated areas. Runoff is very slow. Permeability is moderately slow in the upper part and slow below. Soils not protected by levees are subject to frequent flooding for very long periods (December to June).
USE AND VEGETATION: Used mostly for wheat, oats, barley, hay, pasture, and clover seed. A few areas are used for hops production. Some areas are used for wetland wildlife habitat and recreation. Natural vegetation is mainly sedge, rush, willow, thinleaf alder, and pyramid spirea.
DISTRIBUTION AND EXTENT: Northern Idaho, northwestern Montana, and possibly northeastern Washington. The series is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Boundary County, Idaho, 1974.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 6 inches (Ap horizon)
Redoximorphic features - start at 6 inches (Cg1 horizon)
Particle-size control section - the zone from 10 to 40 inches (part of the Cg1, Cg2, and Cg3 horizons)