LOCATION GOLDBLUFFS CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic, isomesic Typic Dystrudepts
TYPICAL PEDON: Goldbluffs gravelly loam - on a southeast-facing convex slope of 45 percent at 60 meters (200 feet) elevation under redwood, Douglas fir, western hemlock, tanoak, California huckleberry, salmonberry, salal, swordfern, false-lily-of-the-valley, inside-out flower and Oregon grape. (Colors are for moist soil unless otherwise stated. When described July 14, 2004, the soil was moist throughout.)
Oi--0 to 3 centimeter (0 to 1 inch); very dark brown (10YR 2/2) fresh and slightly decomposed conifer needles, tanoak leaves, and twigs; brown (10YR 5/3) dry; common very fine roots; many very fine and fine interstitial pores; 2 percent well-rounded gravel and 1 percent well-rounded cobbles; very strongly acid (pH 4.8); abrupt smooth boundary. (0 to 3 centimeters thick)
A--3 to 25 centimeters (1 to 10 inches); very dark brown (10YR 2/2) gravelly loam, brown (10YR 4/3) dry; moderate fine subangular blocky and strong medium granular; slightly hard, friable, slightly sticky and slightly plastic; common very fine, fine, medium and coarse roots; common very fine and fine interstitial pores and common very fine, fine, medium, and coarse tubular pores; 30 percent well rounded gravel; very strongly acid (pH 4.7); abrupt smooth boundary. (25 to 35 centimeters thick)
Bt1--25 to 42 centimeters (10 to 17 inches); brown (7.5YR 4/4) very gravelly sandy loam, reddish yellow (7.5YR 6/6) dry; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common medium, coarse, and very coarse roots; common very fine and fine interstitial pores and common very fine and medium tubular pores; few distinct clay films on rock fragments; 45 percent well rounded gravel; very strongly acid (pH 4.8); clear smooth boundary.
Bt2--42 to 59 centimeters (17 to 23 inches); strong brown (7.5YR 4/6) very gravelly sandy loam, reddish yellow (7.5YR 6/6) dry; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine, medium, and coarse roots; common very fine and fine interstitial pores and common very fine, fine, and medium tubular pores; few distinct clay films on rock fragments; 50 percent well rounded gravel; very strongly acid (pH 4.5); clear smooth boundary.
Bt3--59 to 95 centimeters (23 to 37 inches); strong brown (7.5YR 5/6) very gravelly sandy loam, reddish yellow (7.5YR 6/6) dry; moderate fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine, medium, coarse, and very coarse roots; common very fine and fine interstitial and tubular pores; few distinct clay films on rock fragments; 52 percent well rounded gravel and 5 percent paragravels; extremely acid (pH 4.4); clear smooth boundary. (Combined thickness of the Bt horizons is 25 to 75 centimeters)
BC--95 to 119 centimeters (37 to 47 inches); brownish yellowish brown (10YR 5/6) very gravelly coarse sandy loam, brownish yellow (10YR 6/6) dry; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common medium and coarse roots; common very fine interstitial pores and common very fine and fine tubular pores; 60 percent well rounded gravel and 15 percent paragravels; extremely acid (pH 4.3); clear wavy boundary. (0 to 30 centimeters thick)
C1--119 to 142 centimeters (47 to 56 inches); yellowish brown (10YR 5/6) extremely gravelly coarse sandy loam, brownish yellow (10YR 6/6) dry; massive; moderately hard, firm, slightly sticky and nonplastic; common medium roots; common very fine interstitial pores and common fine tubular pores; 5 percent prominent manganese coats on rock fragments; 60 percent well rounded gravel and 20 percent paragravels; extremely acid (pH 4.4); clear wavy boundary.
C2--142 to 175 centimeters (56 to 69 inches); yellowish brown (10YR 5/6) extremely gravelly sandy loam, brownish yellow (10YR 6/6) dry; massive; moderately hard, firm, slightly sticky and nonplastic; moderately few very fine interstitial pores; 10 percent prominent manganese coats on rock fragments; 70 percent well rounded gravel, 20 percent paragravels, and 3 percent well rounded cobbles; extremely acid (pH 4.4). (Combined thickness of the C horizons is 50 to 100 centimeters)
TYPE LOCATION: Prairie Creek Redwoods State Park, Humboldt County, California; Miners Ridge, located 0.64 kilometers (0.25 miles) west on Miners Ridge Trail from junction with James Irvine Trail in Prairie Creek Redwoods State Park; southwest quarter, northeast quarter, Section 2, T11N. R. 1E. 41 degrees, 22 minutes, 6 seconds north latitude and 124 degrees, 1 minute, 34 seconds west longitude; HBLM; USGS Orick Quadrangle. UTM Zone 10 414186mE 4580155mN; NAD83
RANGE IN CHARACTERISTICS:
Soil Moisture: The soil is usually moist in all parts in the soil moisture control section in most years, but becomes nearly dry in the upper part from about September 15 to October 15 in most years. The soils have an Udic moisture regime.
Soil Temperature: The mean annual soil temperature is 10 to 13 degrees C (50 to 55 degrees F). The difference between mean summer and mean winter temperature is 2 to 4 degrees C. The soils have an isomesic temperature regime.
Reaction is moderately to very strongly acid throughout. Base saturation is 5 to 35 percent between depths of 25 to 178 centimeters.
Surface fragments: 0 to 20 percent gravel and 0 to 5 percent cobbles.
Particle-Size Control Section (weighted average):
Rock fragments: 35 to 60 percent gravel, 0 to 3 percent cobbles.
Clay content: 5 to 17 percent clay.
O horizon
Hue: 10YR.
Value: 2 through 6 dry and moist.
Chroma: 1 through 4 dry and moist.
Texture: slightly decomposed organic material.
Wood fragments: 0 to 35 percent.
Reaction: moderately to very strongly acid.
A horizon
Hue: 10YR.
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 3 dry, 2 or 3 moist.
Texture of fine earth: loam.
Rock fragments: 30 to 45 percent gravel; 0 to 3 percent cobbles.
Clay content: 15 to 25 percent.
Bt horizon
Hue: 7.5YR or 10YR
Value: 5 or 6 dry, 4 or 5 moist.
Chroma: 4 through 6 dry, 4 through 8 moist.
Texture of fine earth: loamy sand, coarse sandy loam, sandy loam, or loam.
Rock fragments: 35 to 60 percent gravel; 0 to 3 percent cobbles.
Pararock fragments: 0 to 7 percent paragravels.
Clay content: 2 to 17 percent.
C horizon
Hue: 10YR
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 4 through 6 dry, 4 through 6 moist.
Texture of fine earth: loamy sand, coarse sandy loam, or sandy loam.
Rock fragments: 35 to 75 percent gravel, 3 to 7 cobbles.
Pararock fragments: 10 to 20 percent paragravels.
Clay content: 2 to 10 percent.
COMPETING SERIES: At this time there are no other series in this family.
GEOGRAPHIC SETTING: Goldbluffs soils occur on narrow ridges on hillslopes. Slopes are 9 to 50 percent. Elevations are 6 to 309 meters (15 to 1010 feet). The soils formed in colluvium and residuum from weakly consolidated fluvial and beach deposits derived from mixed sources. The climate is humid with cool foggy summers and cool moist winters. Coastal influence limits the annual and diurnal range in temperature. Mean annual precipitation ranges from 1520 to 2030 millimeters (60 to 80 inches). Mean January temperature is about 9 degrees C; mean July temperature is about 14 degrees C; and the mean annual temperature is 10 to 13 degrees C (50 to 55 degrees F). Frost-free season is 280 to 325 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Ossagon and Squashan soils . Ossagon soils are fine-loamy with argillic horizons. The Ossagon soils are on hill slopes. The Squashan soils have argillic horizons and are in similar locations.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained; medium to high runoff; moderately high saturated hydraulic conductivity over high.
USE AND VEGETATION: This soil has been used for commercial timber and is used for recreation, wildlife and watershed. Natural vegetation consists of redwood, Douglas-fir, western hemlock, tanoak, and California huckleberry.
DISTRIBUTION AND EXTENT: California Coastal Redwood Belt; MLRA 4B. The series is not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Humboldt Del Norte area, California 2007. Source of name is from Goldbluffs Beach 3 miles north of the town of Orick.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
1. Ochric epipedon - the zone from 0 to 25 centimeters.
2. Cambic horizon - the zone from 28 to 122 centimeters.
3. Udepts feature - udic soil moisture regime
4. Dystrudepts feature - base saturation of less than 60 percent in one or more horizons between 25 and 75 cm from soil surface.
5. Particle-size control section - the zone from 25 to 100 centimeters, averages 16 percent clay, and 38 percent rock fragments.
ADDITIONAL DATA: NSSL, Lincoln Lab sample number 04N1045.
Soil classified using the 10th Edition of the Keys to Soil Taxonomy.