LOCATION HOOSKANADEN OREstablished Series
TAXONOMIC CLASS: Fine, mixed, superactive, isomesic Andic Hapludalfs
TYPICAL PEDON: Hooskanaden clay loam, grassland, on a 15 percent west-facing slope at an elevation of 240 feet. ( When described on September 20, 1988, the soil profile was moist throughout. Colors are for moist soil unless otherwise noted.)
Oi--1 inch to 0; slightly decomposed needles, leaves, twigs and woody materials.
A1--0 to 5 inches; very dark gray (10YR 3/1) clay loam, dark grayish brown (10YR 4/2) dry; moderate very fine and fine subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic, weakly smeary; many fine and very fine and few coarse roots; many fine tubular pores; 10 percent gravel; strongly acid (pH 5.2); clear smooth boundary.
A2--5 to 15 inches; very dark grayish brown (10YR 3/2) clay loam, grayish brown (10YR 4/2) dry; moderate fine subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic, weakly smeary; many fine and very fine and few coarse roots; many fine continuous tubular pores; 5 percent gravel; strongly acid (pH 5.5); abrupt smooth boundary. (Combined thickness of the A horizon ranges from 12 to 20 inches)
2Bt1--15 to 28 inches; olive brown (2.5Y 4/4) clay, light brownish gray (2.5Y 6/3) dry; moderate fine subangular blocky structure; hard, firm, sticky and plastic; common fine and few coarse roots; many fine continuous tubular pores; many medium distinct dark grayish brown (2.5Y 4/2) iron depletions and yellowish brown (10YR 5/6) masses of iron and manganese accumulations; common distinct clay films on ped faces and in pores; 5 percent gravel; very strongly acid (pH 4.9); abrupt smooth boundary.
2Bt2--28 to 35 inches; dark gray (10YR 4/1) clay, gray (10YR 6/1) dry; strong medium and coarse angular blocky structure; very hard, very firm, very sticky and very plastic; common fine and few coarse roots; many fine continuous tubular pores; many distinct clay films on ped faces and in pores; many medium prominent yellowish brown (10YR 5/6) masses of iron and manganese accumulations; very strongly acid (pH 5.0); clear smooth boundary. (Combined thickness of the 2Bt horizon ranges from 18 to 30 inches)
2C--35 to 60 inches; dark gray (N4/0) clay, light brownish gray (2.5Y 6/2) dry; massive; extremely hard, extremely firm, very sticky and very plastic; few discontinuous tubular pores; many medium prominent yellowish brown (10YR 5/6) and olive brown (2.5Y 4/4) masses of iron and manganese accumulations; 10 percent gravel; moderately acid (pH 5.8).
TYPE LOCATION: Curry County, Oregon; located about 990 feet north and 990 feet west of the southeast corner of section 34, T. 39 S., R. 14 W. (Latitude 42 degrees, 9 minutes, 12 seconds N, Longitude 124 degrees, 20 minutes, 26 seconds W)
RANGE IN CHARACTERISTICS: The mean annual soil temperature is 51 to 54 degrees F. The difference between mean summer and mean winter soil temperature varies from 5 to 9 degrees F. The soils are usually moist and are dry for less than 45 consecutive days in all parts between depths of 4 and 12 inches in the four months following the summer solstice. The particle-size control section is 40 to 50 percent clay and 0 to 10 percent rock fragments. Depth to bedrock is typically 60 inches or more. Depth to the 2C horizon is 30 to 50 inches. The solum is very strongly or strongly acid. The umbric epipedon is 10 to 20 inches thick.
The A horizon has value of 2 or 3 moist, 3 or 4 dry and chroma of 1 or 2 moist and dry. It is clay loam or gravelly clay loam with 27 to 35 percent clay. It has 0 to 20 percent gravel, 1 to 2 percent acid oxalate extractable aluminum plus 1/2 iron, and 60 to 85 percent P-retention. Organic matter is 8 to 12 percent. Moist bulk density is 0.90 to 1.0 g/cc.
The 2Bt horizon has hue of 10YR or 2.5Y, value of 4 or 5 moist, 5 to 7 dry and chroma of 1 to 4 moist and 1 to 3 dry. Many medium distinct or prominent redox depletions with chroma of 2 or less and redox concentrations as masses of iron and manganese occur throughout this horizon. It is silty clay or clay with 40 to 50 percent clay and has 0 to 10 percent gravel. Organic matter is 2 to 4 percent.
The 2C horizon has hue of 2.5Y or 5Y, value of 4 or 5 moist, 6 to 8 dry and chroma of 0 to 2 moist and 2 to 4 dry. Many medium or coarse prominent redox concentrations as masses of iron and manganese occur throughout this horizon. It is clay or silty clay with 40 to 60 percent clay and has 0 to 10 percent gravel. Soil reaction is strongly acid to moderately acid.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Hooskanaden soils occur in concave areas of open grasslands on metastable ridgetops and side slopes of coastal hills and mountains. Slopes are 0 to 60 percent. The soils formed in residuum and colluvium derived from highly sheared and weathered metasedimentary rock types of the Otter Point Formation. Elevations are 200 to 1300 feet. The climate is humid, characterized by cool wet winters and cool moist summers with fog. A strong marine influence limits the diurnal and annual range of temperature. The mean annual precipitation is 75 to 95 inches. The mean annual temperature is 50 to 53 degrees F. The frost-free period is 200 to 270 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Loneranch, Millicoma, Reedsport, Reinhart, Sebastian, and Whaleshead soils. Loneranch soils are fine-loamy, 20 to 40 inches deep to a lithic contact, and are on broad ridgetops and side slopes. Millicoma soils are 20 to 40 inches deep to a paralithic contact and are loamy-skeletal. Reedsport soils are fine-loamy, well drained, 20 to 40 inches deep to a paralithic contact, and are on ridgetops and side slopes. Reinhart soils are 10 to 20 inches deep to a lithic contact, lack an argillic horizon, and are in grassland areas on ridgetops and side slopes. Sebastian soils are loamy-skeletal, 10 to 20 inches deep to a lithic contact, have serpentinitic mineralogy, and are on ridgetops and side slopes. Whaleshead soils are loamy-skeletal and are on side slopes.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; very slow permeability. An apparent high water table fluctuates between depths of 1.0 to 2.5 feet below the soil surface from November through April.
USE AND VEGETATION: These soils are used for pasture, watershed, and wildlife habitat. Native vegetation is western hazel, tanoak, salmonberry, western swordfern, western brackenfern, Pacific poison oak, rush, sedge, crinkleawn fescue, bentgrass, and velvetgrass.
DISTRIBUTION AND EXTENT: Coastal hills and mountains of southwestern Oregon. MLRA 1. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Curry County, Oregon, 1995. The source of the name is a creek in coastal southwestern Curry County.
REMARKS: There is a need to propose an Aquandic subgroup for Hapludalfs.
Diagnostic horizons and features in this pedon include:
Umbric epipedon - from the surface to a depth of 15 inches (A1, A2 horizons).
Argillic horizon - from a depth of 15 to 35 inches (2Bt1 and 2Bt2 horizons).
Base saturation by sum, is 76 percent at a depth of 35 inches (2C horizon)
Aquic feature - the soil has redox depletions with chroma moist of 2 or less in the upper 10 inches of the argillic horizon accompanied by masses of iron and manganese redox concentrations with higher chroma. (2Bt1 horizon)
Andic feature - acid oxalate aluminum plus 1/2 iron is 1.0 percent and moist bulk density is less than 1.0 g/cc from the surface to 15 inches. (A1, A2 horizons)
ADDITIONAL DATA: Reference samples from pedon 89P 196, samples 89P 1194-1198 from Curry County, Oregon sampled by NSSL, Lincoln, NE, 12/89.