LOCATION CASTLECREST             OR

Established Series
Rev. ACM/TDT
01/2011

CASTLECREST SERIES


The Castlecrest series consists of very deep, somewhat excessively drained soils that formed in volcanic ash mixed with pumice, cinders and andesite fragments. Castlecrest soils are on mountain flanks and mountain sides and have slopes of 0 to 80 percent. The mean annual precipitation is about 55 inches and the mean annual temperature is about 41 degrees F.

TAXONOMIC CLASS: Ashy, amorphic Typic Vitricryands

TYPICAL PEDON: Castlecrest ashy paragravelly loamy sand, on a 3 percent slope, forest. (Colors are for moist soils unless otherwise noted. Described by G. Weinheimer and A. Moore, 7/21/99.)

Oi--0 to 1 inch; slightly decomposed needle litter; abrupt wavy boundary. (1 to 2 inches thick)

A--1 to 3 inches; very dark grayish brown (10YR 3/2) paragravelly ashy loamy sand, dark grayish brown (10YR 4/2) dry; single grain; loose, nonsticky and nonplastic; common fine and medium roots; many fine interstitial pores; 15 percent pumice paragravel; slightly acid (pH 6.2); clear smooth boundary. (0 to 15 inches thick)

Bw--3 to 19 inches; brown (10YR 4/3) paragravelly ashy loamy sand, brown (10YR 5/3) dry; single grain; loose, nonsticky and nonplastic; common fine and medium roots; many fine interstitial pores; 15 percent pumice paragravel; slightly acid (pH 6.2); clear smooth boundary. (5 to 16 inches thick)

C1--19 to 26 inches; very dark grayish brown (10YR 3/2) and dark grayish brown (10YR 4/2) ashy sand, brown (10YR 4/3) and brown (10YR 5/3) dry; single grain; loose, nonsticky and nonplastic; many fine interstitial pores; 7 percent pumice paragravel; slightly acid (pH 6.4); clear wavy boundary. (5 to 20 inches thick)

C2--26 to 38 inches; gray (10YR 6/1) and very dark gray (10YR 3/1) ashy coarse sand, light gray (10YR 7/2) and dark grayish brown (10YR 4/2) dry; single grain; loose, nonsticky and nonplastic; many fine interstitial pores; 5 percent pumice gravel; slightly acid (pH 6.4); gradual wavy boundary. (10 to 26 inches thick)

C3--38 to 64 inches; light yellowish brown (10YR 6/4) and very dark gray (10YR 3/1) ashy coarse sand, very pale brown (10YR 7/4) and dark grayish brown (10YR 4/2) dry; single grain; loose, nonsticky and nonplastic; many fine interstitial pores; 5 percent pumice paragravel; slightly acid (pH 6.4).

TYPE LOCATION: Klamath County, Oregon, Crater Lake National Park; about 2.3 miles east northeast of the Pumice Desert view point; UTM Zone 10, 568232 easting, 4765340 northing, NAD 83 (GPS). Latitude - 43 degrees, 02 minutes, 15.5 seconds North; Longitude - 122 degrees, 09 minutes, 44.5 seconds West.

RANGE IN CHARACTERISTICS: The solum is 14 to 30 inches thick. The average annual soil temperature ranges from 39 to 43 degrees F. The soils are usually moist but are dry in all parts of the moisture control section for 30 to 45 consecutive days following the summer solstice. The solum has andic soil properties throughout and have 60 to 90 percent volcanic glass, 1.0 to 2.5 acid oxalate extractable aluminum plus one-half iron, 50 to 85 percent phosphate retention, 3 to 12 percent air-dry 15-bar water content and 4 to 13 percent moist 15-bar water content. The weighted average of 8xSi+2xFe is 5 to 8. The solum averages less than 35 percent pumice, cinder, and andesite fragments and has hue of 10YR or 7.5YR.

The A horizon has value of 2 through 5 moist, 3 through 6 dry, and chroma of 2 through 4 moist and dry. It is ashy loamy sand or ashy sandy loam and contains 0 to 15 percent pumice paragravel, 0 to 8 percent cinder gravel, 0 to 15 percent andesite gravel, and 0 to 3 percent andesite cobbles.

Some pedons lack an A horizon and have an albic horizon (E) up to 3 inches thick when this occurs slopes are typically less than 15 percent.

The Bw horizon has value of 3 or 4 moist, 4 through 6 dry, and chroma of 2 through 4 moist and dry. It is ashy loamy sand, ashy sandy loam, or ashy sand and contains 0 to 15 percent pumice paragravel, 0 to 5 percent cinder gravel, 0 to 20 percent andesite gravel, and 0 to 3 percent andesite cobbles.

The C horizon has value of 3 through 6 moist, 4 through 7 dry, and chroma of 1 through 6 moist, 2 through 6 dry. It is ashy sand, ashy coarse sand, or ashy loamy sand. The upper part contains 0 to 15 percent pumice paragravel, 0 to 20 percent cinder gravel, 0 to 15 percent andesite gravel, and 0 to 2 percent andesite or cinder cobbles. The lower part may contain greater than 35 percent pumice paragravel.

COMPETING SERIES: These are the Belrick, Hutson, Millerpoint, Spexarth and Winegar series. Belrick soils are on glacial moraines with skeletal glacial till at 20 to 40 inches, and have an umbric epipedon. Hutson soils have fine-earth textures of loam, or fine sandy loam with acid oxalate aluminum and half iron of over 2 percent. Millerpoint soils have acid oxalate aluminum and half iron of 2 to 5 percent and have fine-earth textures of sandy loam or fine sandy loam. Spexarth soils are moderately deep to a paralithic contact. Winegar soils are moderately deep to densic materials.

GEOGRAPHIC SETTING: Castlecrest soils are on mountain flanks and mountain sides at elevations of 5,000 to 8,000 feet. Slopes range from 0 to 80 percent. The soils formed primarily in volcanic ash from Mt. Mazama. The climate is characterized by cold wet winters and cool moist summers. The mean annual precipitation is 40 to 70 inches, falling mostly as snow. The mean annual temperature is 38 to 42 degrees F and the frost-free period is 0 to 50 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Unionpeak, Llaorock, and Timbercrater series. Llaorock soils are medial-skeletal and are on adjacent ridges. Timbercrater is ashy-pumiceous. Unionpeak soils have a weakly cemented duripan.

DRAINAGE AND PERMEABILITY: Somewhat excessively drained; runoff is moderate. Permeability is rapid.

USE AND VEGETATION: These soils are used for woodland, wildlife habitat, recreation, and watershed purposes. Vegetation is mountain hemlock, Shasta red fir, and lodgepole pine with a sparse understory of shrubs and herbs.

DISTRIBUTION AND EXTENT: The High Cascade Mountains of south central Oregon; MLRA 3. This series is of limited extent.

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

SERIES ESTABLISHED: Crater Lake National Park, Oregon, 2001.

REMARKS: Diagnostic horizons and features recognized in this pedon are:

Andic soil properties - from 0 to 19 inches, based on laboratory data from associated Timbercrater and Umak series.

Ochric epipedon

Vitri (greatgroup) - the solum averages 60 to 90 percent glass and has an air-dry 15 bar moisture content of 3 to 12 percent

Runoff is moderate due to the hydrophobic nature of the surface horizon. If this property is not present, depending on slope, runoff may be low.


National Cooperative Soil Survey
U.S.A.