LOCATION RAYCREEK ORTentative Series
TAXONOMIC CLASS: Fine-loamy, isotic, frigid Vitrandic Argixerolls
TYPICAL PEDON: Raycreek ashy loam - woodland, on a 15 percent, west-facing slope at an elevation of 5,100 feet. (When described on August 6, 2001, the soil was dry in the surface 12 inches and slightly moist below. Colors are for moist soils unless otherwise noted.)
Oi--0 to 1 inch; slightly decomposed pine needles and dried grass
A--1 to 3 inches; very dark brown (10YR 2/2) ashy loam, grayish brown (10YR 5/2) dry; weak very fine granular structure; soft, very friable, slightly sticky and slightly plastic; many fine and very fine roots; common fine and many very fine irregular pores; 10 percent cobbles; neutral (pH 7.0); clear smooth boundary. (1 to 7 inches thick)
AB--3 to 8 inches; very dark grayish brown (10YR 3/2) ashy sandy loam, brown (10YR 5/3) dry; moderate fine subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; many fine and common very fine roots; common fine and very fine tubular pores; 5 percent cobbles and 5 percent gravel; neutral (pH 7.0); gradual smooth boundary. (0 to 6 inches thick)
2Bt1--8 to 21 inches; dark brown (10YR 3/3) sandy clay loam, brown (10YR 5/3) dry; weak medium subangular blocky structure; hard, firm, slightly sticky and moderately plastic; many fine and common very fine roots; common fine and very fine tubular pores; few faint clay films bridging sand grains; 5 percent gravel; slightly alkaline (pH 7.4); gradual smooth boundary.
2Bt2--21 to 29 inches; very dark grayish brown (10YR 3/2) clay loam, grayish brown (10YR 5/2) dry; weak medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; many fine and common very fine roots; common fine and very fine tubular pores; few faint clay films bridging sand grains; 10 percent gravel; slightly alkaline (pH 7.5); abrupt wavy boundary. (The combined thickness of the 2Bt horizon is 18 to 30 inches.)
2R--29 to 32 inches; tuff.
TYPE LOCATION: Grant County, Oregon, located about 19 miles due west of the town of Seneca; 500 feet west and 1,800 feet south of the northeast corner of section 36, T. 16 S., R. 33 E. (Latitude 44 degrees, 08 minutes, and 37.02 seconds north and Longitude 118 degrees, 35 minutes, and 21.96 seconds west)
RANGE IN CHARACTERISTICS: The soil moisture control section is dry in all parts for 60 to 90 days following the summer solstice. The mean annual soil temperature is 43 to 47 degrees F. Depth to bedrock is 20 to 40 inches. The mollic epipedon is 20 to 30 inches thick and includes all or a part of the argillic horizon. The particle size control section has 25 to 35 percent clay and less than 15 percent rock fragments. The soil reaction is neutral or slightly alkaline throughout.
The A horizon has value of 2 or 3 moist, 4 or 5 dry, and chroma of 2 or 3 moist and dry. It is ashy loam with 15 to 25 percent clay. The AB horizon, when present, is ashy loam or ashy sandy loam. The A and AB horizons have 0 to 10 percent cobbles and 0 to 5 percent gravel with volcanic glass of 15 to 30 percent and estimated acid oxalate aluminum plus one-half acid oxalate iron of 0.2 to 0.4 percent.
The 2Bt horizon has value of 3 or 4 moist, 5 or 6 dry, and chroma of 2 or 3 moist and dry. It is sandy clay loam or clay loam with 25 to 35 percent clay. It has 0 to 15 percent gravel.
COMPETING SERIES: These are the Hess, Lidos, Melhorn, Salcreek and Tourn series. All these soils except Tourn are greater than 40 inches deep to bedrock. Hess soils have soil reaction of moderately or slightly acid and may have small amounts of pararock fragments throughout the profile. Lidos Melhorn, and Salcreek soils have more than 15 percent rock fragments in the particle size control section. Tourn soils are moderately deep to a paralithic contact.
GEOGRAPHIC SETTING: Raycreek soils are on gentle sideslopes which border wet meadows and have slopes of 4 to 25 percent. These soils formed in metasedimentary material. Elevations are 4,800 to 5,800 feet. The climate is characterized by cold wet winters and hot dry summers. The mean annual precipitation is 14 to 24 inches, and the mean annual temperature is 41 to 45 degrees F. The frost-free period is 30 to 80 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Frenchcabin, Loganvalley, Magill, Stanbro, Starglade, and Weberg soils. Frenchcabin soils are fine-silty over sandy or sandy-skeletal, somewhat poorly drained, and are on convex positions within mountain meadows. Loganvalley soils are loamy-skeletal and are on fan remnants. Magill and Starglade soils are loamy-skeletal, and are on hills. Stanbro soils are organic, very poorly drained, and are on fens. Weberg soils are loamy-skeletal, moderately well drained, and are on glacial outwash plains.
DRAINAGE AND PERMEABILITY: Well drained; moderately slow permeability.
USE AND VEGETATION: Timber production and livestock grazing. The native vegetation is Ponderosa pine, elk sedge, mountain big sagebrush, and western juniper.
DISTRIBUTION AND EXTENT: Mountain toeslopes of east-central Oregon; MLRA 43c. The series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES PROPOSED: Grant County, Oregon, 2004. The name is derived from Ray Creek found in the Logan Valley area.
REMARKS: Diagnostic horizon and features recognized in this pedon are:
Mollic epipedon - from 1 to 29 inches
Argillic horizon - 8 to 29 inches
Particle size control section - 8 to 28 inches
Vitrandic features - from 1 to 8 inches (A and AB horizons)
Xeric moisture regime
All depths to diagnostic horizons and other features are measured from the top of the first mineral horizon.