LOCATION ROOSEVELT          WA
Established Series
REV. VB/SBC/TLA
12/97

ROOSEVELT SERIES


The Roosevelt series consists of moderately deep, well drained soils formed in granitic and gneiss residuum and colluvium with a component of loess. These soils are on ridges, shoulders, and backslopes of hills. Slopes are 0 to 70 percent. The average annual precipitation is about 10 inches and the mean annual air temperature is about 50 degrees F.

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Aridic Haploxerolls

TYPICAL PEDON: Roosevelt gravelly loam - on a 14 percent southwest facing slope under native grasses and shrubs at an elevation of 2,320 feet. (Colors are for dry soil unless otherwise noted.)

A1--0 to 3 inches; grayish brown (10YR 5/2) gravelly loam, very dark grayish brown (10YR 3/2) moist; weak fine subangular blocky structure; soft, very friable, nonsticky and nonplastic; common very fine and few fine roots; few very fine interstitial pores; 20 percent gravel; neutral (pH 6.6); clear wavy boundary. (2 to 6 inches thick)

A2--3 to 14 inches; brown (10YR 5/3) gravelly loam, dark brown (10YR 3/3) moist; weak medium subangular blocky structure; soft, friable, nonsticky and nonplastic,; common very fine and few fine and medium roots; few very fine interstitial pores; 15 percent gravel and 5 percent cobbles; neutral (pH 7.0); clear wavy boundary. (8 to 14 inches thick)

Bw--14 to 28 inches; pale brown (10YR 6/3) gravelly sandy loam, dark brown (10YR 4/3) moist; weak medium subangular blocky structure; soft, friable, nonsticky and nonplastic; few very fine and fine roots; few very fine interstitial pores; 15 percent gravel and 5 percent cobbles; neutral (pH 6.6); gradual irregular boundary. (10 to 16 inches thick)

R--28 inches; hard quartz monzonite.

TYPE LOCATION: Okanogan County, Washington; Colville Indian Reservation; 2,100 feet south and 1,600 feet east of northwest corner sec. 5, T. 28 N., R. 31 E., W.M.

RANGE IN CHARACTERISTICS: Mean annual soil temperature is 51 to 53 degrees F. These soils are usually dry in all parts between a depth of 8 and 24 inches for more than half the time when soil temperature is greater than 41 degrees F. Depth to a lithic contact is 20 to 40 inches. Soil reaction is neutral to slightly alkaline. The particle-size control section is 7 to 15 percent clay and 10 to 30 percent rock fragments. The mollic epipedon is 7 to 16 inches thick.

The A horizon has value of 4 or 5 dry and chroma of 2 or 3 dry or moist. It is 15 to 30 percent gravel, 0 to 5 percent cobbles. Structure is weak or moderate granular or weak fine or very fine subangular blocky.

The Bw horizon has value of 5 or 6 dry, 3 or 4 moist and chroma of 3 or 4 dry or moist. It is sandy loam or fine sandy loam. It is 10 to 30 percent gravel, 0 to 10 percent cobbles. Structure is weak or moderate fine or medium subangular blocky.

COMPETING SERIES: These are the Burch, Calpine, Caphealy, Cashmere, Cashmont, Rio King, Roloff, Shantown, Snake Hollow, and Surprise series. Burch, Calpine, Cashmere, Cashmont, Rio King, Snake Hollow, and Surprise soils are more than 40 inches deep. Roloff soils are silt loam or very fine fine sandy loam throughout the particle-size control section. Caphealy soils have a significant influence of sand-size ash (10 to 30 percent glass) throughout the profile. Shantown soils are very deep.

GEOGRAPHIC SETTING: Roosevelt soils are on ridges, shoulders, and backslopes of hills. These soils formed in granitic and gneiss residuum and colluvium with a component of loess. Slopes are 0 to 70 percent. Elevations range from 800 to 2,400 feet. The climate is characterized by warm, dry summers and cool, wet winters. Average annual precipitation ranges from 9 to 12 inches. The mean January temperature is about 25 degrees F. The mean July temperature is about 74 degrees F, and the mean annual temperature is about 50 degrees F. The frost-free season is 140 to 180 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Couleedam, Farrell, Malott, Peshastin, Skaha, Soaplake and Swakane soils. Farrell, Malott Peshastin and Skaha soils are deep. Couleedam, Soaplake, and Swakane soils are 10 to 20 inches to bedrock.

DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderate permeability.

USE AND VEGETATION: Used for livestock grazing, watershed, wildlife habitat and recreation. Native vegetation is bluebunch wheatgrass, Idaho fescue, Sandberg bluegrass, silky lupine, Wyeth eriogonum, low fleabane, threetip sagebrush, and antelope bitterbrush.

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

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

SERIES ESTABLISHED: Okanogan County, Colville Indian Reservation, Washington, 1987.

REMARKS: Diagnostic horizons and features recognized in this soil are a mollic epipedon from the surface to 14 inches, a cambic horizon from 14 to 28 inches, and a lithic contact at 28 inches.


National Cooperative Soil Survey
U.S.A.