LOCATION NACHES WAEstablished Series
TAXONOMIC CLASS: Fine-loamy over sandy or sandy-skeletal, mixed, superactive, mesic Aridic Argixerolls
TYPICAL PEDON: Naches loam - irrigated cropland. (Colors re for dry soil unless otherwise stated.)
Ap1--0 to 5 inches; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; weak fine granular structure; hard, friable, slightly sticky and slightly plastic; many roots; mildly alkaline (pH 7.6); abrupt smooth boundry. (3 to 12 inches thick)
Ap2--5 to 10 inches; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; massive (plow pan); very hard, firm, slightly sticky and slightly plastic; many roots matted on the top and in fractures of the plow pan; mildly alkaline (pH 7.8); abrupt wavy boundary. (0 to 6 inches thick)
Bt--10 to 21 inches; brown (10YR 5/3) sandy clay loam, dark brown (10YR 3/3) moist; moderate medium and coarse pri;smatic structure; hard, friable, sticky and plastic; common roots; few fine pores; common thin clay films on faces of peds; mildly alkaline (pH 7.8); gradual wavy boundry. (6 to 15 inches thick)
Bw--21 to 34 inches; brown (10YR 5/3) loam, dark brown (10YR 3/3) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; common roots; many fine pores; 5 percent pebbles; mildly alkaline (pH 7.8); abrupt wavy boundary. (6 to 20 inches thick)
Bk--34 to 38 inches; light brownish gray (10YR 6/2) fine sandy loam, dark grayish brown (10YR 4/2) moist; massive; soft, very friable, nonsticky and nonplastic; common roots; common fine pores; 5 percent pebbles; violent effervescence; moderately alkaline (pH 8.4); abrupt wavy boundary. (0 to 5 inches thick)
2C--38 to 60 inches; gray (10YR 5/1) extremely gravelly sand, very dark gray (10YR 3/1) moist; single grained; loose; 80 percent pebbles; moderately alkaline (pH 8.0).
TYPE LOCATION: Yakima County, Washington; 200 feet north of the Fort Road and 2,000 feet east of Lateral "C" Road in the SE1/4SW1/4 sec. 1, T. 10 N., R. 18 E. W.M.
RANGE IN CHARACTERISTICS: The mean annual soil temperature at a depth of 20 inches ranges from 47 to 53 degrees F. These soils are usually dry in all parts between depths of 4 and 12 inches when soil temperature is more than 41 degrees F. The mollic epipedon ranges from 7 to 16 inches thick. Depth to contrasting textures is 25 to 40 inches.
The A horizon has hue of 10YR or 7.5YR, value of 4 or 5 dry, 2 or 3 moist, and chroma of 2 or 3 dry or moist. It is neutral or mildly alkaline.
The Bt horizon has hue of 10YR or 7.5YR, value of 4 or 5 dry, 3 or 4 moist, and chroma of 3 or 4 moist or dry. It is heavy loam, heavy silt loam, clay loam or sandy clay loam. This horizon has moderate blocky or prismatic structure. It has 15 to 50 percent sand coarser than very fine sand, 25 to 35 percent clay and 0 to 15 percent coarse fragments. It is mildly alkaline or moderately alkaline.
The Bw and Bk horizons have hue of 10YR or 2.5Y, value of 4 through 6 dry, and chroma of 2 through 4 dry. Texture is silt loam to fine sandy loam and has 5 to 35 percent coarse fragments.
The 2C horizon has hue of 10YR or 2.5Y, value of 4 through 6 dry, 3 through 5 moist, and chroma of 1 through 3 dry and moist. It is extremely gravelly loamy sand or very gravelly sand or extremely gravelly soils.
COMPETING SERIES: These are the Munnell series and the similar Ashue series. Munnell soils lack a Bk horizon and have an argillic horizon more than 15 inches thick. Ashue soils are loamy-skeletal.
GEOGRAPHIC SETTING: Naches soils are on terraces at elevations of 700 to 900 feet. Slope is 0 to 5 percent. These soils formed in old alluvium. They occur in a climate with warm, dry summers and cold, moist winters. Average annual precipitation is 6 to 9 inches. Average January temperature is 29 degrees F, average July temperature is 74 degrees F, and the mean annual temperature is about 5l degrees F. Frost-free season is 130 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Ashue soils and the Toppenish, Track, and Yakima soils. All of these soils lack an argillic horizon. In addition, Toppenish and Track soils are somewhat poorly drained. Yakima soils have a mollic epipedon more than 20 inches thick.
DRAINAGE AND PERMEABILITY: Well drained; slow runoff; moderate permeability in the solum and very rapid in the 2C horizon.
USE AND VEGETATION: Most of these soils are used for irrigated cropland. Common crops grown are hops, mint, orchards, vineyards, truck crops, corn, hay, and pasture. Native vegetation was bluebunch wheatgrass, big sagebrush, and Sandberg bluegrass.
DISTRIBUTION AND EXTENT: Yakima River Valley in south-central Washington. The series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Kittitas County, Washington, 1937.
REMARKS: Diagnostic horizons and feature recognized in this pedon are a mollic epipedon from the surface to 10 inches, an argillic horizon from 10 to 21 inches, and a lithologic change to sandy-skeletal material at 38 inches.