LOCATION MCMEEN OR+IDEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Haplic Haploxerollic Durixerolls
TYPICAL PEDON: McMeen silt loam, cultivated. (Colors are for moist soil unless otherwise noted.)
Ap--0 to 8 inches; black (10YR 2/1) silt loam, gray (10YR 5/1) dry; moderate very fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine roots; many very fine irregular pores; 2 percent cobbles and 5 percent pebbles; netural (pH 6.6); abrupt smooth boundary. (6 to 9 inches thick)
A--8 to 14 inches; very dark brown (10YR 2/2) silty clay loam, grayish brown (10YR 5/2) dry; weak fine subangular blocky and very fine granular structure; hard, friable, sticky and plastic; many very fine roots; many very fine tubular pores; 2 percent cobbles and 5 percent pebbles; neutral (pH 7.2); gradual wavy boundary. (0 to 8 inches thick)
Bw--14 to 27 inches; very dark grayish brown (10YR 3/2) silty clay loam, grayish brown (10YR 5/2) dry; weak medium subangular blocky structure; hard, friable, sticky and plastic; many very fine roots; many very fine tubular pores; 10 percent pebbles and 5 percent cobbles; few 1/2 inch firm strongly calcareous nodules; mildly alkaline (pH 7.4); abrupt smooth boundary. (10 to 25 inches thick)
2Bqm--27 to 39 inches; pale brown (10YR 6/3) cobbly duripan, white (10YR 8/1) dry; massive; weakly cemented; very hard, very firm; discontinuously coated with opal on upper part of the horizon; 25 percent cobbles and 5 percent pebbles; strongly calcareous; strongly alkaline (pH 8.7).
TYPE LOCATION: Wasco County, Oregon; 100 feet south of Tub Springs road in the NW1/4 SW1/4 Nw1/4 section 36, T. 8 S., R. 16 E.
RANGE IN CHARACTERISTICS: The soils are usually moist but are dry throughout between depths of 4 and 12 inches for 80 consecutive days or more within 3 months following the summer solstice. The mean annual soil temperature ranges from 47 to 50 degrees F. (estimated). The control section averages 27 to 35 percent clay. Rock fragments range from few scattered pebbles or cobbles in the A horizons to as much as 15 percent in the B horizon and 20 to 50 percent in the duripan. Depth to the duripan is 20 to 40 inches.
The A horizon has value of 2 or 3 moist, 4 or 5 dry, and chroma of 1 or 2 moist and dry. It is loam, silt loam, or silty clay loam and has weak or moderate granular and very fine and fine subangular blocky structure.
The B horizon has value of 3 or 4 moist, 5 or 6 dry and chroma of 2 or 3 moist and dry. It is clay loam or silty clay loam with more than 15 percent coarser than very fine sand. It has weak medium subangular blocky to granular structure. The lower part of the B horizon is moderately calcareous to noncalcareous and contains few firm, weakly to strongly calcareous nodules which also are throughout the B horizon in some pedons.
The IICsim horizon (duripan) ranges from weakly to strongly cemented. Thin opal or silica laminae are on more than half of the surface of the duripan.
COMPETING SERIES: These are the Baker, Endicott, and Willis series. Baker and Willis soils are usually dry, have indurated duripans, and have less than 18 percent clay in the texture control section. Endicott soils have duripans that are indurated in some subhorizon and have less than 18 percent clay in their control sections.
GEOGRAPHIC SETTING: McMeen soils are on nearly level to moderately steep upland plains at elevations of 2,700 to 4,600 feet. Slopes range from 0 to 12 percent. These soils formed in loess mixed from sediments. The climate is semiarid continental with a mean annual precipitation of 9 to 14 inches. The mean summer temperature is 61 to 64 degrees F. The mean winter temperature is 31 to 34 degrees F. The mean annual temperature ranges from 45 to 48 degrees F. The average frost-free period (32 degrees F.) is 50 to 120 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Curant, Gribble, Rail and Tub soils. All of these soils lack duripans except Gribble. Gribble soils have clayey-skeletal argillic horizons. Tub soils have clayey argillic horizons. Rail soils lack a duripan over depth of 40 inches.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff; moderately slow permeability to the duripan.
USE AND VEGETATION: The principal use is production of small grains. Other uses are range, pasture, wildlife and water supplying purpose. Native vegetation is bluebunch wheatgrass, Idaho fescue, Sandberg bluegrass and big sagebrush.
DISTRIBUTION AND EXTENT: Central Oregon and southern Idaho. The series is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Wasco County (Trout Creek-Shaniko Area), Oregon, 1970.
NSTH 17, RECLASSIFICATION ONLY, 3/95