LOCATION FRENCHOLLOW IDEstablished Series
TAXONOMIC CLASS: Fine, smectitic, frigid Typic Haploxererts
TYPICAL PEDON: Frenchollow silty clay loam, rangeland; on a 18 percent slope at 6,450 feet elevation. When described on June, 28 1989, the soil was moist below 2 inches. (Color is for air dry soil unless otherwise noted.)
A1--0 to 5 inches; dark grayish brown (10YR 4/2) silty clay loam, very dark brown (10YR 2/2) moist; strong very fine and fine granular structure; soft, very friable, moderately sticky and moderately plastic; many very fine roots; many very fine irregular pores; vertical cracks present, 0.5 to 1.5 inches wide and about 1 to 2 feet apart; 5 percent gravel; neutral (pH 7.1); clear smooth boundary. (4 to 10 inches thick)
A2--5 to 12 inches; brown (10YR 4/3) silty clay loam, very dark brown (10YR 2/2) moist; moderate coarse prismatic structure parting to strong fine and medium subangular blocky; hard, friable, moderately sticky and moderately plastic; common very fine and few fine roots; many very fine irregular pores and many very fine and medium, and few fine tubular pores; vertical cracks present, 0.5 to 1.5 inch wide and about 1 to 2 feet apart; 5 percent gravel; neutral (pH 7.2); clear wavy boundary. (6 to 10 inches thick)
BA--12 to 20 inches; brown (10YR 5/3) silty clay, very dark grayish brown (10YR 3/2) moist; moderate coarse prismatic structure parting to strong fine and medium subangular blocky; hard, friable, very sticky and very plastic; common very fine and medium roots; many very fine irregular pores and common very fine and fine tubular pores; vertical cracks present, 0.25 to .5 inches wide and about 1 to 2 feet apart; 2 percent gravel; neutral (pH 7.2); clear wavy boundary. (0 to 8 inches thick)
Btss1--20 to 29 inches; light yellowish brown (10YR 6/4) silty clay, brown (10YR 4/3) moist; strong medium and coarse prismatic structure parting to moderate medium subangular blocky; very hard, friable, very sticky and very plastic; common very fine and medium roots; common very fine irregular pores and many very fine tubular pores; many distinct clay films on faces of peds; vertical cracks present, 0.25 to .5 inch wide and about 1 to 2 feet apart; many intersecting slickensides; slightly alkaline (pH 7.4); gradual wavy boundary. (9 to 11 inches thick)
Btss2--29 to 52 inches; brown (7.5YR 5/4) silty clay, brown (7.5YR 4/4) moist; moderate medium and coarse prismatic structure parting to moderate medium subangular blocky; very hard, friable, very sticky and very plastic; common very fine roots; many very fine tubular pores; common distinct clay films on faces of peds; common intersecting slickensides; 2 percent gravel; slightly alkaline (pH 7.5); clear wavy boundary. (23 to 35 inches thick)
Btkss--52 to 62 inches; brown (7.5YR 5/4) silty clay, brown (7.5YR 4/4) moist; moderate coarse prismatic structure parting to moderate medium subangular blocky; hard, very friable, very sticky and very plastic; common very fine roots; many very fine tubular pores; many distinct clay films on faces of peds; slightly effervescent matrix; violently effervescent lime segregated into many fine and medium irregular shaped filaments, seams and soft masses; few intersecting slickensides; 2 percent gravel; slightly alkaline (pH 7.8).
TYPE LOCATION: Bear Lake County, Idaho; about 1 mile southwest of Fishaven; about 250 feet east and 200 feet north of the southwest corner of sec. 15, T.16 S., R.43 E. 42 degrees 1 minute, 49 seconds north latitude, 111 degrees, 25 minutes, 21 seconds west longitude.
RANGE IN CHARACTERISTICS:
Thickness of Mollic epipedon - 14 to 20 inches
Depth to the Cambic horizon - 14 to 20 inches
Average annual soil temperature - 40 to 43 degrees F
Reaction - neutral through moderately alkaline
Particle-size control section
Texture - SICL or SIC in the upper part, SIC or C in the lower part Clay content - 35 to 50 percent in the upper part, 45 to 60 percent in the lower part
Clay content average - 40 to 55 percent
A horizon
Value - 4 or 5 dry, 2 or 3 moist
Chroma - 2 or 3 dry, 1 through 3 moist
Texture - SICL
Clay content - 30 to 40 percent
BA horizon
Value - 4 through 6 dry, 3 or 4 moist
Chroma - 2 through 4 dry, 1 through 3 moist
Texture - SICL or SIC
Clay content - 35 to 50 percent
Bt horizons
Hue - 10YR or 7.5YR
Value - 5 or 6 dry
Chroma - 3 or 4 moist
Texture - SICL, SIC or C
Clay content - 35 to 50 percent
Btk horizon (absent in some pedons)
Value - 5 or 6 dry
Texture - SIC or C
Clay content - 35 to 50 percent
Calcium carbonate equivalent - 10 to 35 percent
Reaction - slightly or moderately alkaline
COMPETING SERIES: These are the Bagval, Hawkins, Obnot, and Obray series. Bagval soils have secondary carbonates at 30 to 40 inches and have a mollic epipedon greater than 30 inches thick. Hawkins soils do not have clay films in the B horizons and have a hue of 2.5Y in some part. Obnot soils have secondary carbonates at 30 to 39 inches. Obray soils have a mollic epipedon 31 to 45 inches thick.
GEOGRAPHIC SETTING: Frenchollow soils are on hills and terraces. Slopes range from 1 to 20 percent. Elevations range from 5,900 to 6,600 feet. The soil formed in silty alluvium from mixed sources. The average annual precipitation ranges from 13 to 20 inches, the average annual air temperature is 37 to 43 degrees F and the frost free season is 70 to 95 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ant Flat, Dutchcanyon (T), Joes and Yeates Hollow series. Ant Flat soils have secondary lime within 35 inches of the surface and do not have cracks during the year. Dutchcanyon soils have a coarse-loamy particle-size control section and have a carbonatic mineralogy. Joes soils have a fine-silty particle-size control section and are calcareous to the surface. Yeates Hollow soils have a clayey-skeletal particle-size control section. Ant Flat, Dutchcanyon and Yeates Hollow soils are on hillsides with generally east or south aspects adjacent to Frenchollow soils. Joes soils are on terraces generally below Frenchollow soils.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; very slow permeability.
USE AND VEGETATION: Frenchollow soils are used for nonirrigated and irrigated cropland. Typical crops consist of small grains and alfalfa. The potential natural vegetation is basin big sagebrush, bluebunch wheatgrass and sod-forming grasses.
DISTRIBUTION AND EXTENT: Southeastern Idaho. The soils of this series are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Bear Lake County, Idaho, 2008.
REMARKS: NSSL sample S89ID007004 (partial characterization)
Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - the zone from the surface to 20 inches (the A1, A2 and BA horizons)
Clay films - observed in the zone from 20 to 62 inches (the Btss1, Btss2 and Btkss horizons). Lab data indicated there was not enough clay increase for an argillic horizon.
Slickensides- the zone from 20 to 62 inches (the Btss1, Btss2 and Btkss horizons).
Particle-size control section - the zone from 10 to 40 inches (part of the A2, BA, Bt1, and part of the Bt2 horizons)