LOCATION NARNETT IDEstablished Series
TAXONOMIC CLASS: Fine-silty, mixed, active Andic Haplocryalfs
TYPICAL PEDON: Narnett medial silt loam-logged on a 15 percent slope at 3,960 feet elevation. Aspect is south by southeast. (Colors are for dry soil unless otherwise stated. When described on November 9, 1983, the soil was moist throughout).
A--0 to 9 inches; yellowish brown (10YR 5/4) medial silt loam, dark yellowish brown (10YR 3/4) moist; weak medium and fine subangular blocky structure; soft, very friable, slightly sticky and nonplastic; many very fine and fine roots; many very fine, fine, and medium irregular and tubular pores; 2 percent gravel; 3 percent mica flakes; slightly acid (pH 6.5); clear smooth boundary. (3 to 13 inches thick)
2Bw--9 to 15 inches; light yellowish brown (10YR 6/4) silt loam, dark yellowish brown (10YR 4/4) moist; weak coarse subangular blocky structure parting to weak fine subangular blocky; slightly hard, very friable, moderately sticky and moderately plastic; common very fine, fine, and medium roots; many fine and medium irregular and, many very fine tubular pores; 2 percent gravel; 3 percent mica flakes; moderately acid (pH 6.0); clear smooth boundary. (0 to 17 inches thick)
2Bt1--15 to 24 inches; very pale brown (10YR 7/4) silt loam, yellowish brown (10YR 5/6) moist; with pockets of light yellowish brown (10YR 6/4) silt loam, dark yellowish brown (10YR 4/4) moist; moderate medium subangular blocky structure; slightly hard, friable, moderately sticky and moderately plastic; common very fine and fine roots; many very fine and fine tubular pores; 3 percent gravel; matrix has bridging of sand grains and few faint clay films on the faces of peds and in pores, and organic stains in pores; 3 percent mica flakes; strongly acid (pH 5.5); clear smooth boundary.
2Bt2--24 to 32 inches; very pale brown (10YR 7/4) silt loam, yellowish brown (10YR 5/6) moist; moderate medium and fine subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common very fine roots, some as root mats, common very fine and fine tubular, common fine irregular pores; 3 percent gravel; bridging of sand grains and few faint clay films on the faces of peds and in pores; 3 percent mica flakes; strongly acid (pH 5.5); clear smooth boundary.
2Bt3--32 to 50 inches; very pale brown (10YR 7/4) clay loam, yellowish brown (10YR 5/6) moist; moderate coarse and medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; few fine and medium roots; common very fine and fine tubular and, common fine irregular pores; 5 percent gravel; common faint clay films on the faces of peds and in pores; 10 percent of this horizon is dense and brittle when moist; 3 percent mica flakes; strongly acid (pH 5.5); gradual smooth boundary. (2Bt horizons 17 to 40 inches thick)
3BC1--50 to 54 inches; yellow (10YR 7/6) silt loam, yellowish brown (10YR 5/8) moist; moderate coarse and medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; common fine and medium roots; common fine irregular and, few fine tubular pores; 5 percent gravel; common brownish yellow (10YR 6/8) iron stains; 10 percent mica flakes; strongly acid (pH 5.5); abrupt smooth boundary.
3BC2--54 to 58 inches; very pale brown (10YR 7/4) silt loam, yellowish brown (10YR 5/6) moist; moderate coarse and medium subangular blocky structure; hard, friable, moderately sticky and moderately plastic; few fine roots; common fine irregular and, few fine tubular pores; 5 percent gravel; 10 percent mica flakes; common strong brown (7.5YR 5/6) iron stains; few distinct clay films in pores; strongly acid (pH 5.5); abrupt wavy boundary. (3BC horizons 13 to 22 inches thick)
3C--58 to 80 inches; very pale brown (10YR 7/4) very gravelly silt loam, yellowish brown (10YR 5/6) moist; massive; hard, friable, moderately sticky and moderately plastic; few fine roots; few fine irregular, few fine tubular pores; 30 percent gravel, 5 percent cobbles; strong brown (7.5YR 5/6) iron stains; 10 percent mica flakes; very strongly acid (pH 4.8).
TYPE LOCATION: Clearwater County, Idaho; about 10 miles northeast of Pierce, Idaho in the Clearwater Mountains; about 1,100 feet north and 800 feet west of the southeast corner of section 4, T. 37 N., R. 6 E.; Latitude - 46 degrees, 34 minutes, 28 seconds North; Longitude - 115 degrees, 42 minutes, 0 seconds West. USGS French Mountain quadrangle.
RANGE IN CHARACTERISTICS:
Soil Moisture - usually moist year round and not dry for 45 consecutive days during June to October (Udic moisture regime)
Average annual soil temperature - 42 to 45 degrees F.
Average summer soil temperature - 44 to 46 degrees F. with 2 1/2 inches of O horizon (Cryic temperature regime)
Thickness of volcanic ash surface layers - 7 to 13 inches
Depth to the base of the argillic - 30 to 55 inches
A horizon
Hue - 10YR or 7.5YR dry or moist
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 3 or 4 moist or dry
Clay content - 8 to 12 percent
Rock fragments - 0 to 3 percent
Reaction - strongly acid to neutral
Bulk density - 0.68 to 0.91 g/cc
Acid-oxalate Al+1/2Fe - 1.2 to 2.2 percent
Bw horizons (when present)
Hue - 10YR to 7.5YR dry or moist
Value - 5 or 6 dry, 3 or 4 moist
Chroma - 4 or 6 dry or moist
Clay content - 8 to 16 percent
Rock fragments - 0 to 3 percent gravel
Reaction - strongly acid or moderately acid
2Bw horizons (absent in some profiles)
Hue - 10YR or 7.5YR dry or moist
Value - 6 or 7 dry, 4 or 5 moist
Texture - SIL, L
Clay content - 17 to 24 percent
Rock fragments - 0 to 3 percent gravel
Reaction - strongly acid to neutral
2Bt horizons
Hue - 10YR or 7.5YR dry or moist
Value - 5 to 7 dry, 4 or 5 moist
Chroma - 4 or 6 dry, 3 to 6 moist
Texture - SIL, CL, SICL, L
Clay percent - 16 to 32 percent
Rock fragments - 0 to 10 percent gravel, 0 to 5 percent cobbles, 0 to 10 percent total fragments
Reaction - very strongly acid to neutral
3BC horizons
Hue - 10YR or 7.5YR moist
Value - 6 or 7 dry, 4 or 5 moist
Chroma - 4 or 6 dry, 4 to 8 moist
Texture - SIL, L, GR-L, GR-SIL, CL
Clay content - 18 to 29 percent
Rock fragments - 0 to 20 percent gravel, 0 to 10 percent cobbles, 0 to 20 percent total fragments
Reaction - very strongly acid to slightly acid
3C horizon
Hue - 10YR or 7.5YR moist
Value - 6 or 7 dry, 4 or 5 moist
Chroma - 4 to 6 dry or moist
Texture - GRV-SIL, GRV-L, L, SIL, GR-SL, GR-S
Clay content - 12 to 25 percent
Rock fragments - 0 to 30 percent gravel, 0 to 5 percent cobbles, 0 to 35 percent total fragments
Reaction - very strongly acid to slightly acid
COMPETING SERIES: This is the Meadowport series. Meadowport soils do not have a 3C horizon and have Btb horizons.
GEOGRAPHIC SETTING: Narnett soils are on old stream terraces and mountain footslopes. These soils formed in alluvium from mixed sources, dominated by loess, with a thin mantle of volcanic ash. Slopes are 5 to 30 percent. Elevations are 3,200 to 4,400 feet. The climate is cool and moist. The mean annual precipitation is 40 to 60 inches; mean annual temperature is 38 to 41 degrees F.; and the frost-free season is 30 to 100 days (9 in 10 years to 1 in 10 years, respectively).
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Mushel and Dullaxe soils. These soils are frigid and on mountain slopes.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff; moderately slow permeability.
USE AND VEGETATION: These soils are used for timber production, livestock grazing, homesites, recreation, and wildlife habitat. Potential natural vegetation is subalpine fir, douglas fir, grand fir, western white pine, western larch, and lodgepole pine, with an understory of wild ginger, greencup beadlily, beargrass, bunchberry dogwood, myrtle pachystima, goldthread, violet, common princes pine, longtube twinflower, starry false-Solomons-seal, western rattlesnake plantain, American trailplant, shinyleaf spirea, labrador tea, and huckleberry.
DISTRIBUTION AND EXTENT: Northern Idaho. This soil is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Clearwater County, Idaho 2003.
REMARKS: Diagnostic horizons and other features recognized in this pedon are:
Ochric epipedon - the zone from 0 to 15 inches (A and 2Bw horizons).
Argillic horizon - the zone from 15 to 50 inches (2Bt1, 2Bt2, and 2Bt3 horizons).
Cambic horizon - the zone from 9 to 15 inches (2Bw horizon)
Substratum - the zone from 58 to 80 inches (3C horizon)
Volcanic ash mantle - the zone from 0 to 9 inches (A horizon)
Particle size control section - the zone from 15 to 35 inches (2Bt1, 2Bt2 and part of the 2Bt3 horizon)
The ranges in values listed under the A horizon for Bulk density and Acid-oxalate extractable Al+1/2Fe are estimates only.
This soil was formerly classified as Fine-loamy, mixed Andeptic Cryoboralfs