LOCATION FERNHAVEN OREstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, mesic Typic Paleudults
TYPICAL PEDON: Fernhaven gravelly loam - on a south facing mountain sideslope of 55 percent under coniferous forest at 950 feet elevation. (Colors are for moist soil unless otherwise stated.)
0i--4 inches to 0; organic layer of decomposing twigs, fir needles, leaves and roots.
A1--0 to 4 inches; dark brown (10YR 3/3) gravelly loam, yellowish brown (10YR 5/4) dry; moderate fine and medium granular structure; soft, friable, slightly sticky and slightly plastic; many very fine, fine and medium roots; many very fine irregular pores; 15 percent gravel; strongly acid (pH 5.4); clear smooth boundary. (3 to 6 inches thick)
A2--4 to 12 inches; dark yellowish brown (10YR 4/4) gravelly loam, pale brown (10YR 6/3) dry; moderate very fine and fine subangular blocky and fine granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine and fine and common medium roots; many very fine and fine irregular pores; 15 percent gravel; strongly acid (pH 5.4); clear smooth boundary. (6 to 10 inches thick)
BAt--12 to 21 inches; dark brown (7.5YR 4/4) loam, light yellowish brown (10YR 6/4) dry; moderate medium and coarse subangular blocky structure; slightly hard, firm, slightly sticky and slightly plastic; common very fine and fine roots; many fine and medium continuous tubular pores; few faint strong brown (7.5YR 4/6) clay films on faces of peds and lining pores; 10 percent gravel; strongly acid (pH 5.2); clear smooth boundary. (4 to 8 inches thick)
Bt1--21 to 31 inches; dark brown (7.5YR 4/4) loam, light yellowish brown (10YR 6/4) dry; moderate medium and coarse subangular blocky structure; hard, firm, sticky and slightly plastic; few fine roots; many very fine and fine continuous tubular pores; common distinct strong brown (7.5YR 4/6) clay films on faces of peds and lining pores; 10 percent soft gravel and 10 percent hard gravel; very strongly acid (pH 5.0); clear smooth boundary. (6 to 12 inches thick)
Bt2--31 to 50 inches; strong brown (7.5YR 4/6) clay loam, light yellowish brown (10YR 6/4) dry; moderate medium and coarse subangular blocky structure; hard, firm, sticky and plastic; few fine roots; common very fine and fine continuous tubular pores; many distinct strong brown (7.5YR 4/6) clay films on faces of peds, lining pores and on surfaces of coarse fragments; 15 percent soft and 10 percent hard gravel; very strongly acid (pH 4.8); clear smooth boundary. (10 to 24 inches thick)
Bt3--50 to 63 inches; dark yellowish brown (10YR 4/6) clay loam, light yellowish brown (10YR 6/4) dry; weak medium and coarse subangular blocky structure; hard, firm, sticky and plastic; very few very fine roots; common fine continuous tubular pores; common distinct brown (7.5YR 4/4) clay films on faces of peds and lining pores; 10 percent gravel; very strongly acid (pH 4.6); clear smooth boundary. (0 to 15 inches thick)
BCt--63 to 72 inches; dark yellowish brown (10YR 4/6) loam; brownish yellow (10YR 6/6) dry; massive; soft, very friable, slightly sticky and slightly plastic; few prominent clay coatings on faces of weathered gravel; 10 percent gravel; very strongly acid (pH 4.6).
TYPE LOCATION: Douglas County, Oregon, about 8 miles northwest of Drain; 2,100 feet east and 1,750 feet north of SW corner of section 3, T. 21 S., R. 6 W.
RANGE IN CHARACTERISTICS: The soils are usually moist throughout, but have a dry period of less than 45 consecutive days during the summer. The mean annual soil temperature is 50 to 55 degrees F. Depth to a paralithic contact and solum thickness is greater than 60 inches. Hue is 10YR or 7.5YR.
The A horizon has value of 3 or 4 moist, 5 through 7 dry and chroma of 3 through 6 moist and dry. It has 15 to 25 percent gravel and 0 to 10 percent cobbles. Clay content is 18 to 25 percent.
The Bt horizon has value of 4 or 5 moist, 5 through 7 dry, and chroma of 3 through 6 moist and dry. It is gravelly loam, loam or clay loam with 25 to 35 percent clay. It has 10 to 25 percent gravel and 0 to 10 percent cobbles. Clay films are few faint to many distinct. Base saturation by sum is 25 to 45 percent.
The BCt horizon has value of 4 or 5 moist, 5 through 7 dry, and chroma of 3 through 6 moist and dry. It is loam or gravelly loam, with 15 to 25 percent clay. It has 5 to 20 percent gravel and 0 to 15 percent cobbles. Base saturation by sum is 20 to 35 percent.
COMPETING SERIES: This is the Buckshot series. Buckshot soils formed over granodiorite, contain 15 to 30 percent coarse and very coarse sand in the particle-size control section and contain less than 15 percent gravel.
GEOGRAPHIC SETTING: Fernhaven soils are on mountain sideslopes. Elevations are 800 to 2,500 feet. Slopes are 3 to 75 percent. The soils formed in colluvium and residuum from sandstone and siltstone of the Tyee and Elkton Formations. The climate is characterized by warm wet winters and hot moist summers. The mean annual precipitation is 55 to 90 inches, and mean annual temperature is 45 to 53 degrees F. The frost-free period is 145 to 240 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Digger, Honeygrove, and Umpcoos series. Digger soils are loamy-skeletal and 20 to 40 inches to a paralithic contact. Honeygrove soils are clayey. Umpcoos soils are 10 to 20 inches to a lithic contact and are loamy-skeletal.
DRAINAGE AND PERMEABILITY: Well drained; moderate permeability.
USE AND VEGETATION: These soils are used for timber production and wildlife habitat. The forest is dominated by Douglas-fir and western hemlock. The understory consists of salal, cascade Oregon grape, brackenfern, western swordfern, hazel and vine maple being common.
DISTRIBUTION AND EXTENT: Coast Range Mountains of Oregon; MLRA 1. The soils are of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Douglas County, Oregon, 1994
REMARKS: Diagnostic horizons and other features: Ochric epipedon
Argillic horizon- the zone from 21 to 63 inches ( Bt1, Bt2, Bt3 horizons)
Particle-size control section- The zone from 21 to 41 inches, average clay content is about 27 percent.
Base saturation is less than 35 percent in the Bt2, Bt3, BCt horizons.
This draft (4/92) reflects a change in classification from Hapludults to Paleudults based on less than 20 percent clay within 150 cm. from the soil surface.
ADDITIONAL DATA: Reference samples collected by Oregon State University in 1979 and 1983.