LOCATION VERHART            WA
Established Series
Rev. BJD/TDT
08/2006

VERHART SERIES


The Verhart series consists of moderately deep, well drained soils formed in residuum and colluvium from sedimentary rock with a component of volcanic ash in the upper part. These soils are on upper backslopes, shoulders and ridges of mountains usually with southerly aspects. Slopes are 35 to 65 percent. The average annual precipitation is about 30 inches, and the average annual temperature is about 39 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, isotic Vitrixerandic Haplocryepts

TYPICAL PEDON: Verhart stony ashy sandy loam, on a southwest-facing 61 percent slope at an elevation of 6,500 feet in a subalpine fir, whitebark pine and Douglas-fir forest. (Colors are for dry soil unless otherwise stated. All textures are apparent field textures.)

Oe--0 to 1 inch; partially decomposed needles and twigs; abrupt smooth boundary.

A--1 to 5 inches; brown (10YR 5/3) stony ashy sandy loam, dark brown (10YR 3/3) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine and fine, and few medium roots; common fine irregular pores; 10 percent pebbles, 5 percent cobbles and 10 percent stones; neutral (pH 6.6); clear wavy boundary. (3 to 5 inches thick)

Bw--5 to 12 inches; pale brown (10YR 6/3) very gravelly ashy sandy loam, brown (10YR 4/3) moist; weak fine and medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and fine, and few medium roots; common very fine and fine irregular pores; 30 percent pebbles and 5 percent cobbles; slightly acid (pH 6.4); clear smooth boundary. (7 to 11 inches thick)

2C--12 to 25 inches; pale brown (10YR 6/3) very gravelly sandy loam, brown (10YR 5/3) moist; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; few fine irregular pores; 40 percent pebbles, 5 percent cobbles and 3 percent stones; slightly acid (pH 6.4); clear wavy boundary. (12 to 17 inches thick)

2R--25 inches; sandstone.

TYPE LOCATION: Okanogan County, Washington; about 16 miles northwest of Winthrop Wa., about 1,100 feet west and 800 feet north of the southeast corner of section 20, T. 37 N., R. 20 E. (Latitude 48 degrees 41' 19"N., Longitude 120 degrees 22' 7"W.)

RANGE IN CHARACTERISTICS: The average annual soil temperature is 37 to 41 degrees F. The average summer soil temperature ranges from 42 to 46 degrees F. These soils are usually moist but are dry in all parts of the moisture control section for 45 to 60 consecutive days following the summer solstice. The upper 7 to 14 inches has an estimated bulk density of 1.10 to 1.30 g/cc, volcanic glass content of 5 to 20 percent, acid-oxalate extractable aluminum plus one-half of the acid-oxalate extractable iron of 0.4 to 1.0 percent, and 15-bar water retention of 5 to 10 percent for air dried samples. Depth to a lithic contact is 20 to 40 inches. The particle-size control section averages 35 to 70 percent rock fragments and 3 to 8 percent clay.

The A horizon has values of 4 to 6 dry, 3 to 5 moist, and chromas of 2 or 3 dry or moist. Reaction ranges from slightly acid to neutral.

The Bw horizon has values of 3 or 4 moist. It is gravelly ashy sandy loam, very gravelly ashy sandy loam or very cobbly ashy sandy loam. It has 25 to 40 percent pebbles, 5 to 20 percent cobbles, and 0 to 5 percent stones.

The 2C horizon has values of 5 or 6 dry, 4 or 5 moist, and chromas of 2 or 3 dry or moist. It is very gravelly sandy loam, very cobbly sandy loam, or extremely gravelly sandy loam. It has 35 to 45 percent pebbles, 5 to 20 percent cobbles and 0 to 5 percent stones.

COMPETING SERIES: These are the Torpy, Volmont, Wellsfar and Winsand series. Torpy soils are very deep. Volmont soils have 8 to 15 percent clay and formed in andesite. Wellsfar soils have a paralithic contact. Winsand soils are 40 to 60 inches to bedrock.

GEOGRAPHIC SETTING: Verhart soils are on upper backslopes, shoulders and ridges of mountains usually with southerly aspects. Elevations range from 4,800 to 6,600 feet. Slopes are 15 to 65 percent. These soils formed in residuum and colluvium from sedimentary rock with a component of volcanic ash in the upper part. The climate is characterized by cold, wet winters and cool, dry summers. Average annual precipitation ranges from 25 to 35 inches. Average January temperature ranges from 18 to 22 degrees F.; Average July temperature ranges from 52 to 58 degrees F.; and the average annual air temperature is about 37 to 42 degrees F. The frost free season is 60 to 90 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Banker, Gatewall, and the competing Winsand soils. The Banker soils are on shoulders, ridges and backslopes with northerly aspects and are shallow. Gatewall soils are on backslopes, are very deep and have a volcanic ash mantle 7 to 14 inches thick.

DRAINAGE AND PERMEABILITY: Well drained, rapid runoff; moderately rapid permeability

USE AND VEGETATION: Used for wildlife habitat, watershed and recreation. Native vegetation is subalpine fir, whitebark pine and Douglas-fir, with an understory of pinegrass, silky lupine, common yarrow, heartleaf arnica, kinnikinnick, luina and aster.

DISTRIBUTION AND EXTENT: Northcentral Washington. This series is of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Okanogan National Forest, Okanogan County, Washington, 2005.

REMARKS: Diagnostic horizons and features in this pedon include:
Ochric epipedon - 1 to 5 inches (A horizon)
Cambic horizon - 5 to 12 inches (Bw horizon)
Lithic contact - 25 inches (R horizon)
PSCS - zone from 11 to 25 inches.
Vitrandic feature - zone from 1 to 12 inches

Depth to diagnostic horizon and features are measured from the top of the first mineral horizon.


National Cooperative Soil Survey
U.S.A.