LOCATION COURT OREstablished Series
TAXONOMIC CLASS: Coarse-loamy over sandy or sandy-skeletal, mixed, superactive, mesic Vitritorrandic Haploxerolls
TYPIFYING PEDON: Court ashy sandy loam, cultivated. (Colors are for dry soil unless otherwise noted.)
Ap--0 to 5 inches; grayish brown (10YR 5/2) ashy sandy loam, very dark grayish brown (10YR 3/2) moist; very weak thick platy structure; hard, friable, slightly sticky and slightly plastic; many very fine roots; 15 percent sand-size pumice; neutral (pH 6.6); gradual smooth boundary. (3 to 6 inches thick)
A--5 to 14 inches; grayish brown (10YR 5/2) ashy sandy loam, very dark grayish brown (10YR 3/2) moist; very weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine roots; many very fine tubular pores; 15 percent sand-size pumice; neutral (pH 6.8); clear smooth boundary. (8 to 12 inches thick)
AB--14 to 23 inches; brown (10YR 5/3) ashy sandy loam, dark brown (10YR 3/3) moist; very weak medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine roots; many very fine tubular pores; 15 percent sand-size pumice; neutral (pH 7.0); clear smooth boundary. (4 to 12 inches thick)
2Bw--23 to 29 inches; pale brown (10YR 6/3) loam, brown (10YR 4/3) moist; moderate fine subangular blocky structure; hard, friable, slightly sticky and moderately plastic; many very fine roots; many very fine tubular pores; 8 percent gravel and 2 percent cobbles; neutral (pH 7.2); abrupt irregular boundary. (0 to 10 inches thick)
3Bk--29 to 60 inches; pale brown (10YR 6/3) extremely gravelly loamy sand, brown (10YR 4/3) moist; massive; hard in place and loose when disturbed; 60 percent gravel and 10 percent cobbles; strongly effervescent; moderately alkaline (pH 8.4).
TYPE LOCATION: Jefferson County, Oregon; 100 feet from center of gravel road in the SW1/4 SE1/4 NW1/4 of sec. 33, T.13S., R.14E.
RANGE IN CHARACTERISTICS:
Court soils are dry for one-half to three-fourths of the time when the soil temperature is above 41 degrees F. The soils are dry for 90 to 120 consecutive days. The mean annual soil temperature is 48 to 52 degrees F. Organic matter decreases to less than 1 percent at depths of less than 20 inches. Depth to very gravelly loamy sand or very gravelly sand and depth to secondary carbonates is 20 to 40 inches. The A and AB horizons have phosphate retention of 15 to 25 percent, 15 to 30 percent glass, acid oxalate aluminum plus one-half the iron of 0.4 to 0.8 percent and is asy sandy loam or ashy fine sandy loam. The upper part of the particle-size control sectin has 10 to 18 percent clay.
The A horizon has 0 to 20 percent pebbles, chroma of 2 or 3 moist and dry. It has weak platy or granular to weak subangular blocky structure.
The 2Bw horizon has value of 5 or 6 dry and 3 or 4 moist. It has weak to moderate subangular blocky structure. It has 5 to 20 percent pebbles and cobbles.
The 2Bk horizon has value of 5 or 6 dry and 3 or 4 moist. It has 55 to 65 percent pebbles and 10 to 15 percent cobbles. It has 1 to 5 percent calcium carbonate and 5 to 10 percent clay.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Court soils are on alluvial fans at elevations of 2,500 to 4,000 feet. Slopes range from 1 to 8 percent. These soils formed in moderately coarse and medium textured eolian material high in ash over very gravelly loamy sand or sand. The climate is semiarid with hot, dry summers and cold, moist winters. Mean annual precipitation is 8 to 12 inches. The mean summer temperature is 61 degrees to 64 degrees F., the mean winter temperature is 32 degrees to 36 degrees F., and the mean annual temperature is 46 to 50 degrees F. The frost-free period is 70 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Courtrock, Lamonta, McCoin, Metolius, and Simas soils soils. Metolius soils are more than 40 inches deep to contrasting textures. Lamonta, McCoin, and Simas soils are upland soils. Lamonta soils have duripans and are fine textured. McCoin soils are less than 20 inches deep to a paralithic contact. Simas soils have fine textured argillic horizons. Courtrock soils lack the vitrandic properties in the upper part of the profile.
DRAINAGE AND PERMEABILITY: Well-drained and moderately rapid permeability.
USE AND VEGETATION: These soils are used mainly for the production of irrigated alfalfa-grass hay and for dryland pasture. Other uses include grazing, wildlife and water-supplying purposes.
DISTRIBUTION AND EXTENT: Central Oregon; MLRA 10, pumice zone. The series is inextensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Jefferson County (Trout Creek-Shaniko Area), Oregon, 1970.
REMARKS: Diagnostic horizons and other features:
Molic epipedon - 0 to 14 inches; organic matter is less than one percent in the 14 to 23 inch layer.
Cambic horizon - 23 to 29 inches but is not always present.
Vitritorrandic properties - 0 to 23 inches
Calcidic subgroup properties - 29 to 60 inches