LOCATION WILLOWDALE OREstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Cumulic Haploxerolls
TYPICAL PEDON: Willowdale loam, cultivated. (Colors are for dry soil unless otherwise noted.)
Ap1--0 to 5 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; weak fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine irregular pores; weakly effervescent in spots; moderately alkaline (pH 8.2); clear smooth boundary. (4 to 8 inches thick)
Ap2--5 to 11 inches; grayish brown (10YR 5/2) loam, very dark brown (10YR 2/2) moist; massive; hard, friable, slightly sticky and slightly plastic; common fine roots; many very fine tubular pores; some segregated lime; moderately alkaline (pH 8.2); clear wavy boundary. (0 to 8 inches thick)
Ak1--11 to 18 inches; grayish brown (10YR 5/2) loam, very dark brown (10YR 2/2) moist; weak coarse prismatic and weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine tubular pores; some segregated lime; 15 percent pumice sand; moderately alkaline (pH 8.2); abrupt wavy boundary. (4 to 8 inches thick)
Ak2--18 to 24 inches; dark grayish brown (10YR 4/2) loam, very dark brown (10YR 2/2) moist; weak coarse prismatic and moderate medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine tubular pores; some segregated lime; 10 percent pumice sand; moderately alkaline (pH 8.3); abrupt wavy boundary. (0 to 8 inches thick)
ACk--24 to 40 inches; grayish brown (10YR 5/2) loam, very dark grayish brown (10YR 3/2) moist; weak coarse prismatic structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine roots; many very fine tubular pores; some segregated lime; strongly effervescent; moderately alkaline (pH 8.4); clear wavy boundary. (10 to 20 inches thick)
Ck1--40 to 48 inches; pale brown (10YR 6/3) loam, dark brown (10YR 3/3) moist,; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; many very fine pores; some segregated lime; strongly effervescent; moderately alkaline (pH 8.4). (5 to 20 inches thick)
2Ck2--48 to 60 inches; variegated sand and gravel; loose; nonsticky and nonplastic; some segregated lime; strongly effervescent; moderately alkaline (pH 8.4)
TYPE LOCATION: Jefferson County, Oregon; 890 feet west, 110 feet south of NE corner NE1/4 NE1/4 section 17, T.9S., R.15E.
RANGE IN CHARACTERISTICS: The mean annual soil temperature is estimated to range from 47 to 54 degrees F. The soils are usually dry and are continuously dry in all parts between depths of 4 and 12 inches during the 3 month period following the summer solstice. The mineralogy is mixed and contains 10 to 20 percent pumice sands. The 10 to 40 inch control section 18 to 27 percent clay and more than 15 percent coarser than very fine sand. Rock fragments are commonly absent in the control section but some pedons may have up to 20 percent. Volcanic ash or pumice sand may occur in thin lenses throughout the solum. The profiles are calcareous throughout but may be noncalcareous above 20 inches.
The A horizon has value of 2 or 3 moist, 3 to 5 dry and chroma of 2 or 3 moist and dry. It is loam or sandy loam with 0 to 19 percent gravel.
The ACk, and Bk horizon when present, has color similar to the A horizon. It is loam, sandy loam, or gravelly sandy loam with 0 to 20 percent gravel.
The Ck horizon has value of 3 or 4 moist, 5 or 6 dry and chroma of 2 to 4 moist and dry. It is fine sandy loam, sandy loam, silt loam, loam or sandy clay loam with 0 to 20 percent gravel and 0 to 5 percent cobbles. Stratified very gravelly sand to extremely gravelly silt loam textures may occur below 40 inches. Rock fragments range from 30 to 50 percent gravel and 0 to 15 percent cobbles.
COMPETING SERIES: These are the Birdow, Blackrock, Coit, Dagor, Eastcan, Goose Creek, Goosenawt (T), Gosinta, Lakeview, Monroe (T), Oxy (T), Shoepeg (T), and Soquel series. Birdow soils lack horizons containing carbonates and ash. Blackrock soils are usually moist and contain 20 to 35 percent rock fragments in the control section. Coit soils are poorly drained. Dagor soils lack carbonates. Eastcan soil are moderately well drained and are mottled at 25 to 40 inches. Goose Creek soils are moderately well to somewhat poorly drained and lack horizons containing carbonates and ash. Goosenawt soils lack pumice sand within the particle-size control section. Gosinta soils are moderately well drained and lack pumice sand. Lakeview soils are moderately well drained, are noncalcareous and have a cambic B horizon. Monroe soils lack horizons containing carbonates and ash and have a surface layer 5 to 9 inches thick. Oxy soils are moderately deep. Shoepeg soils are somewhat poorly drained and lack pumice sand. Soquel soils are noncalcareous and have a mean annual soil temperature of 56 to 58 degrees F.
GEOGRAPHIC SETTING: The Willowdale soils are on level or very gently sloping flood plains and alluvial fans at elevations of 1,100 to 4,700 feet. The soils formed in mixed recent alluvium with an influence of volcanic ash. The climate is characterized by cool and moist winters and hot and dry summers.. The mean annual precipitation is 9 to 12 inches. The mean annual temperature is 47 to 52 degrees F. The frost free period is 50 to 160 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Lithgow and Simas soils on uplands and the somewhat poorly drained Rail soils on flood plains. Lithgow and Simas soils have argillic horizons. Rail soils are fine textured throughout.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: These soils are used dominantly for livestock grazing. It is also used for irrigated small grain, grass and alfalfa production, and wildlife habitat. Native vegetation is basin wildrye, bluebunch wheatgrass, bluegrasses.
DISTRIBUTION AND EXTENT: East central Oregon; MLRA B10. 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 features recognized in this pedon:
Mollic epipedon - from 0 to 40 inches (Ap1, Ap2, Ak1, Ak2, and ACk horizons.
Cumulic feature - irregular decrease in organic carbon with increasing depth assumed)
Particle-size control section - from 10 to 40 inches (lower Ap2 horizon and Ak1, Ak2, and ACk horizons)
Aridic soil moisture regime