LOCATION WHITECAP IDEstablished Series
TAXONOMIC CLASS: Mixed Lithic Cryopsamments
TYPICAL PEDON: Whitecap gravelly loamy coarse sand, forested. (Colors are for dry soil unless otherwise stated.)
A11-- 0 to 3 inches; the upper 0.4 inch is light brownish gray (10YR 6/2) gravelly light coarse sandy loam, very dark grayish brown (10YR 3/2) moist and has partially uncoated sand particles. The rest is brown is brown (10YR 5/3) gravelly light coarse sandy loam, very dark grayish brown (10YR 3/2) moist; weak very fine, fine, and medium granular structure; soft, very friable, nonsticky, nonplastic; many very fine and fine roots; many very fine interstitial and tubular pores; few 6 to 12 mm. spots of paler material with thin brown material immediately below; 20 percent angular fine gravel; much mica; moderately acid (pH 6.0); clear smooth boundary. (2 to 4 inches thick)
A12-- 3 to 8 inches; brown (10YR 5/3) gravelly loamy coarse sand, very dark grayish brown (10YR 3/2) moist; very weak fine and medium subangular blocky structure that parts to weak very fine and fine granular structure; soft, very friable, nonsticky, nonplastic; many very fine and common fine roots; many very fine interstitial and tubular pores; few 6 to 12 mm. spots of paler material; 20 percent angular fine gravel; moderately acid (pH 5.8) clear wavy boundary. (2 to 5 inches thick)
C1-- 8 to 13 inches; pale brown (10YR 6/3) and about 1/3 of light gray (10YR 7/2) gravelly loamy coarse sand, dark yellowish brown (10YR 4/4) and brown (10YR 5/3), respectively, moist; weak very fine granular structure; soft, very friable, nonsticky, nonplastic; common very fine and fine roots; many very fine interstitial and common very fine tubular pores; one (or more) light yellowish brown (10YR 6/4) 4-mm. thick lamells, which is brown (10YR 4/3) moist, 25 percent angular fine gravel; moderately acid (pH 5.8); clear wavy boundary. (2 to 7 inches thick)
C2-- 13 to 17 inches; very pale brown (10YR 7/3) and about 1/3 pale brown (10YR 6/3) gravelly light loamy coarse sand, brown (10YR 5/3) and yellowish brown (10YR 5/4) moist; few spots of light yellowish brown (10YR 6/4), brown (10YR 4/3) moist; structureless, massive; slightly hard, very friable, nonsticky, nonplastic; few very fine and fine roots; common very fine tubular pores; 25 percent angular gravel, mostly less than 5 mm. across; moderately acid (pH 5.7); abrupt irregular boundary. (2 to 5 inches thick)
C3-- 17 to 25 inches; very pale brown (10YR 8/2) consolidated porphyritic granitic bedrock; about 1/3 stained reddish yellow (7.5YR 6/6 and 5YR 6/6) and light brown (7.5YR 6/4); moderately fractured; hard displaced fragments can be broken in hands; may have 1 or more lamellae.
TYPE LOCATION: Valley County, Idaho, NE1/4 NW1/4 Sec. 14, T. 11N., R. 5 E.; 40 percent southerly slope at 6,200 feet elevation.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 30 to 38 degrees F., and the mean summer soil temperature at the paralithic contact is 49 to 59 degrees F., if no O horizon. The soils are not dry in some part below 12 inches for 60 consecutive days in more than 7 out of 10 years and are not dry in some part below 12 inches for 90 cumulative days. The mineralogy is mixed. A paralithic contact with somewhat weathered granitic bedrock is at 10 to 20 inches. The control section is loamy sand or coarser, commonly is fine gravelly, but contains less than 35 percent coarse fragments. The dark surface layer is not thick enough (4 to 9 inches) and high enough in organic matter to qualify for an umbric (or mollic) epipedon. Some pedons have a very thin faint A2 horizon immediately below the O horizon, consisting of coarse sand and 40 to 70 percent fine gravel. The profiles have a 10YR hue.
The A1 horizon has a color value of 5 dry and 3 moist and a chroma of 3 or 2. The structure ranges from very weak subangular blocky to weak granular. The reaction is mostly medium acid but ranges from pH 5.5 to 6.2. The base saturation of the A1 horizon is likely less than 50 percent. The organic matter in the A1 horizon is estimated to have a C:N ratio of 15 to 19.
The C1 layer ranges in color value from 6 to 8 dry and 4 to 6 moist. The texture ranges from fine gravelly loamy coarse sand to gravelly coarse sand, and the horizon is mainly structureless. The lower part of the C layer has remnants of the bedrock structure. The reaction of the C layer is mostly medium acid, and the acidity tends to increase slightly with depth. One or more very thin brown lamellae are common in the C1 or C2 layer, and one or more may be in the upper part of the weathered bedrock.
COMPETING SERIES: There are no other family members. Similar soils are the Blanchard, Bryan, Clark Fork, Corbett, Elmira, Graylock, Hanks, Koppes, McCaffery, Pyle, Quartzburg, Stacum, and Toiyabe series. All except the Toiyabe soils have no bedrock within 20 inches of the surface. The Blanchard, Clark Fork, Corbett, Elmira, McCaffery, and Quartzburg soils have a mean summer soil temperature at 20 inches warmer than 59 degrees F., if no O horizon. The Blanchard, Clark Fork, and McCaffery soils are dry in some subhorizon between 12 and 36 inches for 90 cumulative days. The Bryan soils have an umbric epipedon. The Graylock and Stecum soils have more than 35 percent coarse fragments in the control section. The Hanks soils have a moderately coarse textured cambic horizon. The Koppes soils have a mollic epipedon. The Quartzburg soils have a paralithic contact between 20 and 40 inches. The Toiyabe soils have a mean summer temperature at the paralithic contact warmer than 59 degrees F., if no O horizon, and are dry below 12 inches for 60 consecutive days or longer.
GEOGRAPHIC SETTING: These soils are in broad crests of ridges and in side slopes associated with granitic outcrops. Slopes range from 5 to 60 percent. All slope aspects are represented. The elevations are 6,000 to 8,700 feet. The soils are forming in residuum weathered from quartz nonzonite and related bedrock. The mean annual precipitation is 32 to 45 inches, including 10 to 15 feet of snowfall. The average freeze-free period ranges from about 20 to 70 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Graylock, Hanks, and Josie series. The Josie soils have a cambic horizon and no bedrock above 20 inches.
DRAINAGE AND PERMEABILITY: Excessively drained; medium or rapid runoff; and rapid permeability.
USE AND VEGETATION: Used for forestry, grazing, watershed, recreation, and wildlife. The dominant vegetation is Douglas-fir, lodgepole pine, subalpine fir, ponderosa pine, and (or) Whitebark pine and an understory of Aplopappus, Oregon grape, big sagebrush, snowberry, currant, eriogonum cinquefoil, beard-tongue, phlox, sandwort, and elk sedge. Forage production is low, and most areas are uncommercial for timber production.
DISTRIBUTION AND EXTENT: Idaho Batholith in south-central Idaho. The series is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana.
SERIES ESTABLISHED: Middle Fork Payette River Area, Boise and Valley Counties, Idaho, 1969.
REMARKS:
On 3/4/2009 this description is being entered for the first time into the OSD files. Although it was established in 1969 it has never been in an electronic form. Except for the classification, this series has not been reviewed or updated.