LOCATION LONERANCH               OR

Established Series
Rev. MHF/CDJ/RWL
06/2011

LONERANCH SERIES


The Loneranch series consists of moderately deep, moderately well drained soils that formed in colluvium and residuum derived dominantly from highly sheared and weathered metasedimentary rock. Loneranch soils occur in open grassland areas on broad ridgetops and side slopes of coastal hills and mountains. Slopes are 0 to 60 percent. The mean annual precipitation is about 85 inches and the mean annual temperature is about 51 degrees F.

TAXONOMIC CLASS: Fine-loamy, isotic, isomesic Aquandic Humudepts

TYPICAL PEDON: Loneranch gravelly medial clay loam, pasture, on a 29 percent south-facing slope at an elevation of 650 feet. (When described on October 5, 1988, the soil was dry to a depth of 17 inches and moist below this depth. Colors are for moist soil unless otherwise noted.)

A--0 to 3 inches; very dark gray (10YR 3/1) gravelly medial clay loam, dark grayish brown (10YR 4/2) dry; weak very fine subangular blocky structure parting to weak very fine granular; slightly hard, friable, slightly sticky and slightly plastic, weakly smeary; many fine and very fine and few medium and coarse roots; many fine and very fine irregular pores; 15 percent gravel; strongly acid (pH 5.4); clear smooth boundary. (2 to 7 inches thick)

BA--3 to 9 inches; very dark gray (10YR 3/1) gravelly medial clay loam; dark grayish brown (10YR 4/2) dry; moderate very fine and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic, weakly smeary; many fine and very fine and few medium and coarse roots; many fine and very fine tubular pores; 20 percent gravel and 5 percent cobbles; strongly acid (pH 5.5); clear wavy boundary. (0 to 7 inches thick)

Bw1--9 to 17 inches; very dark grayish brown (10YR 3/2) gravelly clay loam, dark brown (10YR 4/3) dry; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and very fine and few medium and coarse roots; many fine and very fine tubular pores; 25 percent gravel and 5 percent cobbles; strongly acid (pH 5.2); gradual wavy boundary.

Bw2--17 to 24 inches; very dark grayish brown (10YR 3/2) gravelly clay loam, grayish brown (10YR 5/2) dry; moderate fine and medium subangular blocky structure; sightly hard, friable, slightly sticky and slightly plastic; many fine and very fine and few medium and coarse roots; many fine and very fine tubular pores; common distinct organic coatings on ped faces and in pores; 25 percent gravel and 5 percent cobbles; strongly acid (pH 5.2); abrupt wavy boundary.

Bw3--24 to 27 inches; dark brown (10YR 3/3) very gravelly clay loam, pale brown (10YR 6/3) dry; moderate fine and medium subangular blocky structure; hard, firm, moderately sticky and moderately plastic; many fine and very fine and few medium and coarse roots; many fine and very fine tubular pores; common distinct organic coatings on ped faces and in pores; common fine distinct dark grayish brown (10YR 4/2) redox depletions and brown (10YR 4/3) masses of iron accumulations; 30 percent gravel and 10 percent cobbles; very strongly acid (pH 5.2). (Combined thickness of the Bw horizon ranges from 18 to 28 inches)

R--27 inches; fractured siltstone or shale.

TYPE LOCATION: Curry County, Oregon; located about 330 feet north and 1200 feet west of the southeast corner of section 2, T. 40 S., R. 14 W., W.M. (Latitude 42 degrees, 8 minutes, 9 seconds N.; Longitude 124 degrees, 19 minutes, 19 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 has 30 to 35 percent clay and 25 to 35 percent coarser than very fine sand. It has 15 to 40 percent rock fragments with the weighted average being less than 35 percent. Depth to a lithic contact is 20 to 40 inches. The umbric epipedon is 20 to 30 inches thick and includes part of the Bw horizon. The upper 7 to 14 inches has acid oxalate extractable aluminum plus one-half iron of 1.0 to 2.0 percent. Hue is 10YR or 7.5YR.

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 gravelly medial clay loam with 27 to 35 percent clay. It has 15 to 20 percent gravel and 0 to 5 percent cobbles. Moist bulk density is 0.9 to 1.0 g/cc. Organic matter is 7 to 10 percent.

The BA horizon, when present, has color similar to the A horizon. It is gravelly medial clay loam with 30 to 35 percent clay. It has 10 to 20 percent gravel and 0 to 5 percent cobbles. Moist bulk density is 0.9 to 1.0 g/cc.

The Bw horizon has value of 3 or 4 moist, 4 through 6 dry and chroma of 2 through 4 moist and dry. Common fine distinct redox depletions with chroma of 2 occur below 20 inches. It has 30 to 35 percent clay. The Bw1 and Bw2 horizons have 10 to 30 percent gravel and 0 to 5 percent cobbles. The Bw3 horizon is gravelly clay loam or very gravelly clay loam and has 20 to 30 percent gravel and 5 to 10 percent cobbles.

COMPETING SERIES: These are the Grassyknob, Reedsport, Skipanon, and Svensen series. All these soils lack redox depletions with chroma of 2. In addition, Reedsport soils are 20 to 40 inches deep to a paralithic contact. Skipanon and Svensen soils are 40 to 60 inches deep to bedrock.

GEOGRAPHIC SETTING: Loneranch soils occur in open grassland areas on metastable broad ridgetops and side slopes of coastal hills and mountains. Slopes are 0 to 60 percent. The soils formed in colluvium and residuum derived dominantly from highly sheared and weathered metasedimentary rock types of the Otter Point Formation. Elevations is 200 to 1,300 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 Hooskanaden, Reedsport, Reinhart, Sebastian, and Whaleshead soils. Hooskanaden soils are very deep to bedrock, clayey, somewhat poorly drained, and are in concave areas on broad ridgetops and side slopes. Reedsport soils are 20 to 40 inches deep to a paralithic contact, well drained, and are on ridgetops and side slopes. Reinhart soils are 10 to 20 inches deep to a lithic contact and are in grassland areas on ridgetops and side slopes. Sebastian soils are loamy-skeletal, 10 to 20 inches deep, have serpentinitic mineralogy, and are on ridgetops and side slopes. Whaleshead soils are very deep and loamy-skeletal and are on side slopes.

DRAINAGE AND PERMEABILITY: Moderately well drained; moderately slow permeability. An apparent high water table fluctuates between depths of 2 to 2.5 feet from November to April.

USE AND VEGETATION: These soils are used for pasture, watershed, and wildlife habitat. Native vegetation is scattered Sitka spruce, Douglas-fir, and red alder, western hazel, salmonberry, western swordfern, western brackenfern, Pacific poison oak, sedge, bentgrass and velvetgrass.

DISTRIBUTION AND EXTENT: Coastal hills and mountains of southwestern Oregon. MLRA 4A. The series is inextensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Curry County, Oregon, 1995.

REMARKS: Diagnostic horizons and features in this pedon include:

Umbric epipedon - from the surface to a depth of 24 inches (A, BA, Bw1, Bw2 horizons).

Some pedons have a cambic horizon; in this pedon the Bw is only 3 inches thick

The soil has base saturation of less than 35 percent by ammonium acetate in some subhorizon between depths of 10 and 40 inches and has 20 kilograms of organic carbon per square meter to a depth of 27 inches (based on lab data).

Aquic feature - redox depletions with chroma moist of 2 at a depth of 24 to 27 inches. This horizon is saturated with water from November to April (Bw3 horizon).

Andic feature - from surface to 9 inches acid oxalate aluminum plus 1/2 iron is 1.16 to 1.43 percent and P-retention of 66 to 78 percent. (A and BA horizons)

ADDITIONAL DATA: Reference samples from pedons 89P 195, samples 89P1191-1193 and 92P 392, samples 92P2419-2423 from Curry County, Oregon samples by NSSL, Lincoln, NE, 12/89.


National Cooperative Soil Survey
U.S.A.