LOCATION SKELLOCK ORTentative Series
TAXONOMIC CLASS: Ashy-pumiceous, glassy Aquic Vitricryands
TYPICAL PEDON: Skellock paragravelly ashy fine sandy loam, woodland. (Colors are for moist soil unless otherwise noted.)
A1--0 to 2 inches; very dark gray (10YR 3/1) paragravelly ashy fine sandy loam, gray (10YR 6/1) dry; weak thin platy and weak fine granular structure; very soft, very friable, nonsticky and nonplastic; many very fine roots and many very fine irregular pores; 30 percent gravel-size pumice; slightly acid (pH 6.4); clear smooth boundary. (1 to 3 inches thick)
A2--2 to 8 inches; dark grayish brown (10YR 4/2) paragravelly ashy fine sandy loam, light brownish gray (10YR 6/2) dry; weak very fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; many very fine roots and many very fine irregular pores; 30 percent gravel-size pumice; slightly acid (pH 6.5); gradual smooth boundary. (4 to 7 inches thick)
Bw1--8 to 14 inches; dark grayish brown (10YR 4/2) paragravelly ashy fine sandy loam, light brownish gray (10YR 6/2) dry; weak coarse subangular blocky structure; soft, very friable, nonsticky and nonplastic; many fine and very fine roots; many very fine irregular pores; 30 percent gravel-size pumice; neutral (pH 6.6); gradual smooth boundary. (4 to 10 inches thick)
Bw1--14 to 20 inches; dark grayish brown (10YR 4/2) very paragravelly ashy fine sandy loam, grayish brown (10YR 5/2) dry; massive; soft, very friable, nonsticky and nonplastic; many fine and very fine roots; many very fine irregular pores; 35 percent gravel-size pumice; neutral (pH 6.8); clear wavy boundary. (5 to 10 inches thick)
2C1--20 to 32 inches; olive yellow (2.5Y 6/6) very paragravelly ashy sandy loam, yellow (10YR 8/5) dry; massive; firm and compact, nonsticky and nonplastic; few very fine roots and many very fine irregular pores; 50 percent gravel-size pumice; neutral (pH 6.9); clear smooth boundary. (8 to 12 inches thick)
2C2--32 to 60 inches; brownish yellow (10YR 6/6) extremely paragravelly ashy sandy loam, common faint redox depletions light gray (10YR 7/2), pale brown (10YR 6/3), very pale brown (10YR 8/3) massive; very firm and compact; few roots and many very fine irregular pores; 60 percent gravel-size pumice; neutral (pH 7.0).
TYPE LOCATION: Klamath County, Oregon; 600 feet east and 300 feet south of the northwest corner section 33, T. 32 S., R. 8 E.; about 2 miles east of the Kirk Railroad Station (abandoned).
RANGE IN CHARACTERISTICS: The soils are usually moist but are dry for 45 to 60 consecutive days following the summer solstice. The mean annual soil temperature is 42 to 45 degrees F., the mean summer soil temperature is 52 to 59 degrees F. and with an O horizon is 40 to 47 degrees F., and the mean winter soil temperature is 32 to 35 degrees F. Solum thickness ranges from about 14 to 25 inches. Depth to the firm compact 2C horizon ranges from 15 to 30 inches with redox depletions having chroma of less than 2 occurring below 20 inches. Depth to bedrock is 60 inches or more. Coarse fragments, consisting of paragravel and paracobble size pumice, range from 15 to 30 percent in the upper part of the particle-size control section, to 35 to 70 percent in the lower part. The soil contains more than 70 percent volcanic glass and glass-coated aggregates, phosphate retention of 25 to 50 percent, acid oxalate extractable aluminum plus one-half iron of 0.4 to 1.0 percent, and 15-bar moisture of less than 10 percent based on an air-dried sample. Moist bulk density is 0.70 to 1.00 grams per cubic centimeter. It is slightly acid to neutral.
Some pedons have an O horizon up to 3 inches thick.
The A horizon has value of 2 or 3 moist, 5 or 6 dry, and chroma of 1 or 2 moist and dry. It is paragravelly ashy fine sandy loam or paragravelly ashy sandy loam with 15 to 30 percent gravel-size pumice and 0 to 5 percent cobble-size pumice.
The Bw horizon has hue of 10YR or 7.5YR, value of 3 or 4 moist, 5 to 7 dry with chromas of 1 or 2 dry and 1 to 3 moist. It is ashy fine sandy loam and ashy sandy loam with 15 to 35 percent gravel-size pumice and 0 to 5 percent cobble-size pumice.
The 2C horizon has hue of 5YR to 2.5Y, value of 4 to 7 moist, 5 to 8 dry and chroma of 2 to 6 moist and dry. It is ashy sandy loam, or ashy loamy sand with 35 to 70 percent gravel-size pumice and 0 to 15 percent cobble-size pumice.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Skellock soils occur on nearly level pumice mantled lava plains at elevations of about 4,000 to 4,600 feet. The soils are formed in dacite pumice lapilli and ash deposits about 15 to 120 feet thick. These deposits have been locally reworked by water in the upper few feet in moist places. The climate is characterized by cold wet winters and cool moist summers. The mean annual precipitation is 18 to 35 inches. The mean annual temperature is 40 to 45 degrees F. The frost-free period is 0 to 50 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Steiger, Lapine and Wickiup soils. These soils all lack firm, compact horizons and are very friable throughout. Steiger soils are ashy and lack the redox features. Lapine soils are excessively drained and lack redox features. Wickiup soils have an aquic moisture regime.
DRAINAGE AND PERMEABILITY: Moderately well drained; Permeability is rapid in the upper part and moderately slow in the lower firm and compact 2C horizon. There is a seasonal high water table at a depth of 2.0 to 3.0 feet from April to June.
USE AND VEGETATION: The soils are used for timber production, wildlife habitat, and recreation. Native plants principally consist of lodgepole pine, antelope bitterbrush, pine bluegrass and sedge.
DISTRIBUTION AND EXTENT: Pumice flow deposits in south-central Oregon; MLRA 6. The series is extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Klamath County, Oregon, 1957, Klamath Indian Reservation Survey.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Ochric epipedon
Cambic horizon - from 8 to 20 inches
Aquic feature - from 32 to 60 inches (3C3 horizon) with redox depletions having chroma of 2.
Andic properties - throughout profile; based on data from the Steiger series.
Particle-size control section - from 0 to 40 inches with 0 to 20 meeting the ashy family criteria and 20 to 40 inches meeting the ashy-pumiceous family criteria. The ashy over ashy-pumiceous family class is not a recognized contrasting particle-size class and therefore the ashy-pumiceous class was used based on the range of characteristics for thickness of the 2Chorizon and the weighted average of over 35 percent pumice fragments from 0 to 40 inches.