LOCATION LEADPOINT WAEstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, frigid Vitrandic Haploxerepts
TYPICAL PEDON: Leadpoint ashy silt loam, forested. (Colors are for dry soil unless otherwise stated.)
Oi&Oe--0 to 2 inches; very dark grayish brown (10YR 3/2) moist; loose, partially decomposed organic litter composed of needles, leaves, twigs, bark and cones; slightly acid (pH 6.2); abrupt smooth boundary. (1 to 3 inches thick)
A--2 to 11 inches; very dark gray (10YR 3/1) ashy silt loam, black (10YR 2/1) moist; weak fine and medium subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; many fine and common medium and coarse roots; many fine pores; 5 percent soft and 5 percent hard shale fragments; slightly alkaline (pH 7.6); clear wavy boundary. (6 to 10 inches thick)
2Bw1--11 to 17 inches; very dark gray (N 3/) channery silt loam, black (N 2/) moist; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and common medium and coarse roots; many fine pores; 10 percent parachanners;15 percent hard shale channers; slightly alkaline (pH 7.8); clear wavy boundary. (5 to 7 inches thick)
2Bw2--17 to 26 inches; very dark gray (N 3/) shaly silt loam, black (N 2/) moist; weak medium and coarse subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine, medium and coarse roots; many fine pores; 20 percent soft and 25 percent hard shale fragments; slightly alkaline (pH 7.8); clear wavy boundary. (6 to 10 inches thick)
2C1--26 to 36 inches; black (N 2/) shaly loam, black (N 2/) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; common fine, medium and coarse roots; common fine pores; 30 percent soft and 30 percent hard shale fragments; moderately alkaline (pH 8.2); abrupt irregular boundary. (6 to 10 inches thick)
2C2--36 to 40 inches; black (N 2/) shaly loam; black (N 2/) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few fine, medium and coarse roots; few fine pores; 40 percent soft and 35 percent hard shale fragments; moderately alkaline (pH 8.2); abrupt irregular boundary. (0 to 8 inches thick)
2Cr--40 inches; fractured black (N 2/) carbonaeous shale.
TYPE LOCATION: Stevens County, Washington; 1,200 feet south and 800 feet west of the NE corner of sec. 18, T.39N., R.41E.
RANGE IN CHARACTERISTICS: The depth to a paralithic contact is 27 to 40 inches. The soil is usually moist in all horizons but is dry in all parts between depths of 8 and 24 inches, or to a paralithic contact for 45 to 60 consectutive days. The mean annual soil temperture is 44 to 46 degrees F. The volcanic ash and loess mantle is 7 to 18 inches thick and is estimated to be 5 to 40 percent volcanic glass and the aluuminum plus one-half iron extracted by acid oxilate is estimated to be 0.2 to 1.0 percent. The particle-size control section ranges from 10 to 40 percent shale parachanners and 15 to 35 percent hard shale channers. The soil is neutral to moderately alkaline.
The A horizon has hue of 10YR, 2.5Y, or N, value of 3 through 5 dry, 2 or 3 moist and chroma of 0, 1 or 2. It has fine or medium granular, or fine, medium or coarse subangular blocky structure. It has 5 to 15 percent shale parachanners and 5 to 15 percent hard shale channers.
The 2Bw horizon has hue of 2.5Y, 5Y or N, value of 2 through 5, 2 or 3 moist and chroma of 0, 1 or 2. It has fine or medium granular, or fine, medium or coarse subangular blocky structure. It has 5 to 15 percent shale parachanners and 5 to 15 percent hard shale channers.
The 2C horizon has hue of 2.5Y, 5Y or N, value of 2 through 5 dry, 2 or 3 moist and chroma of 0 or 1. It has 15 to 45 percent shale parachanners and 20 to 35 percent hard shale channers.
COMPETING SERIES: These are the Aits, Ardenmont, Cobbler, Dowwneygulch, Enson, Labuck, Stataloop, Yocridge, and Waits series. Aits, Ardenmont, Cobbler, Enson, Stataloop, and Waits soils are more than 40 inches deep. , Dowwneygulch and Yocridge soils have a lithic contact between 20 and 40 inches. Labuck soils have a paralithic contact underlain by partially decomposed granodiorite.
GEOGRAPHIC SETTING: Leadpoint soils are on glaciated upland hillsides, mountainsides and ridgetops at elevations of 2,500 to 5,000 feet. Slopes are often complex and are 0 to 65 percent. These soils formed in glacial till residuum and colluvium from very dark gray and black Ordovician slates, argillites, shales and siltstones, with a mantle of volcanic ash and loess. In places, the shaly parent rock is interbedded or in contact with limestone or dolomite. The climate is characterized by having warm dry summers and cool moist winters. Mean temperature in January is 24 degrees F., in July 66 degrees F.; and the average annual temperature is 43 to 45 degrees F. The average annual precipitation is 22 to 32 inches. The frost-free season is 80 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ahren, Belzar, Huckleberry, Maki and Smackout soils and the competing Aits and Waits soils. Ahren and Smackout soils are deep and have a fine-loamy control section. Aits and Waits soils are deep and have a coarse-loamy control section. Belzar soils have a loamy-skeletal control section. Huckleberry soils have a medial over loamy control section and have a cryic soil temperature regime. Maki soils have a loamy-skeletal control section and a mesic soil temperature regime.
DRAINAGE AND PERMEABILITY: Well drained; very slow to very rapid runoff; moderate permeability.
USE AND VEGETATION: Used for timber, grazing, some dryland crops, wildlife habitat and recreation. Overstory vegetation is Douglas-fir, grand fir, western larch, western redcedar, paper birch, quaking aspen and alder. Understory vegetation is hazelnut, willow, Saskatoon serviceberry, creambush oceanspray, snowberry, wildrose, redstem ceanothus, huckleberry, buffaloberry, elderberry, chokeberry, thimbleberry and Oregon grape. Ground vegetation is pachistima, pipsissewa, twinflower, strawberry and grasses.
DISTRIBUTION AND EXTENT: Mountainous areas of northeastern Stevens County, Washington. The series is small in extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana
SERIES ESTABLISHED: Stevens County, Washington, 1978.
REMARKS: This revision changes the classification from Coarse-loamy, mixed, frigid Andic Xerochrepts to Coarse-loamy, mixed, superactive, frigid Vitrandic Haploxerepts. The dark color are inherited from the shale.
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - the zone from 2 to 11 inches (A horizon).
Cambic horizon - the zone from 11 to 26 inches (2Bw1 and 2Bw2 horizons).
Paralithic contact - at 40 inches (top of 2Cr horizon).