LOCATION HALFBLUFF CA
Established Series
Rev. FWH/FFH/JJJ/JPS
10/2016
HALFBLUFF SERIES
The Halfbluff series consists of very deep, moderately well drained soils formed in marine deposits from mixed sources. Halfbluff soils are on marine terraces and have slopes of 0 to 9 percent. The mean annual precipitation is about 1500 millimeters (59 inches) and mean annual temperature is about 12 degrees C (54 degrees F).
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, mesic Oxyaquic Humudepts
TYPICAL PEDON: Halfbluff fine sandy loam on a west facing, linear slope of 1 percent under bentgrass, sweet vernalgrass, brome, common velvetgrass, hairy cat's ear and California blackberry, at an elevation of 11 meters (35 feet). (Colors are for moist soils unless otherwise stated. When described on October 11, 2007 the soil was moist throughout.)
A--0 to 28 centimeters (0 to 11 inches); very dark grayish brown (10YR 3/2) fine sandy loam, brown (10YR 5/3) dry; moderate medium granular structure; soft, very friable, nonsticky and slightly plastic; common very fine and fine roots; common very fine and fine irregular and tubular pores; strongly acid (pH 5.4); clear wavy boundary. (25 to 100 centimeters thick)
BA--28 to 46 centimeters (11 to 18 inches); dark brown (7.5YR 3/3) fine sandy loam, brown (7.5YR 5/4) dry; weak fine subangular blocky parting to moderate fine granular structure; slightly hard, friable, nonsticky and slightly plastic; common very fine and fine roots; common very fine and fine irregular pores and common fine and very coarse tubular pores; strongly acid (pH 5.4); clear wavy boundary. (0 to 50 centimeters thick)
Bw1--46 to 72 centimeters (18 to 28 inches); dark brown (7.5YR 3/4) fine sandy loam, strong brown (7.5YR 5/6) dry; moderate fine and medium subangular blocky structure; slightly hard, friable, nonsticky and slightly plastic; common very fine and fine roots; common very fine and fine irregular pores and common very fine tubular pores; strongly acid (pH 5.4); clear wavy boundary.
Bw2--72 to 89 centimeters (28 to 35 inches); brown (7.5YR 4/4) sandy loam, reddish yellow (7.5YR 6/6) dry; weak medium and coarse structure; slightly hard, friable; nonsticky and slightly plastic; moderately few fine roots; common very fine and fine irregular pores; strongly acid (pH 5.2); clear wavy boundary. (Combined thickness of the Bw horizons is 25 to 100 centimeters)
CB--89 to 110 centimeters (35 to 43 inches); olive brown (2.5Y 4/4) sandy loam, olive yellow (2.5Y 6/6) dry; massive; slightly hard, friable, nonsticky and nonplastic; very few very fine roots; many very fine interstitial pores; common fine prominent brownish yellow (10YR 6/6) masses of iron accumulation and common fine prominent grayish brown (10YR 5/2) iron depletions in the matrix; moderately acid (pH 5.8); gradual wavy boundary. (0 to 50 centimeters thick)
2C--110 to 152 centimeters (43 to 60 inches); light olive brown (2.5Y 5/4) loamy sand, yellow (2.5Y 7/6) dry; massive; soft, very friable, nonsticky and nonplastic; many very fine interstitial pores; common fine prominent brownish yellow (10YR 6/6) masses of iron accumulation and common fine prominent grayish brown (10YR 5/2) iron depletions in the matrix; moderately acid (pH 5.6). (20 to 80 centimeters thick)
TYPE LOCATION: Del Norte County, California; located 2.5 kilometers (1.5 miles) north east of Crescent City, California; USGS Crescent City Quadrangle; WGS84 Decimal Degrees 41.77636 latitude and -124.1990591 longitude; UTM Zone 10 400349mE 4625641mN; 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 soil moisture regime and an oxyaquic regime subclass. A seasonal water table is present for 20 or more consecutive days or 30 or more cumulative days in most years within the zone from 75 to 100 centimeters (30 to 40 inches).
Soil temperature: Soil temperature: The mean annual soil temperature at 50 centimeters (20 inches) is 12 to 14 degrees C (53 to 57 degrees F). The average summer soil temperature is about 18 degrees C and the average winter soil temperature is about 9 degrees C. The difference between average summer and winter soil temperatures is about 6 to 9 degrees C. The soils have a mesic temperature regime.
The umbric epipedon is 25 to 75 (8 to 30 inches) centimeters thick.
Base Saturation, by ammonium acetate, is less than 60 percent between depths of 29 to 79 centimeters.
Depth to redoximorphic features: 50 to 100 centimeters
Particle-Size Control Section (weighted average):
Clay content: 10 to 18 percent
A horizon
Hue: 10YRor 7.5YR
Value: 2 or 3, 3 through 5 dry
Chroma: 1 through 3, 2 through 4 dry
Texture of fine earth: fine sandy loam or loam
Rock fragments: 0 to 1 percent gravel
Clay content: 12 to 25 percent
Reaction: very strongly to slightly acid
Bw horizon
Hue: 7.5YR, 10YR, or 2.5Y
Value: 3 through 5, 5 through 7 dry
Chroma: 4 through 8 moist or dry
Texture of fine earth: very fine sandy loam, fine sandy loam, sandy loam, loam, or loamy fine sand
Rock fragments: 0 to 3 percent gravel
Clay content: 6 to 20 percent
Reaction: very strongly to moderately acid
Redoximorphic features: fine and medium iron-manganese masses in matrix, along root channels and along pores
Amount: few, common, or many
Hue: 5YR, 7.5YR, or 10YR
Value: 4 or 5
Chroma: 4 through 8
Redoximorphic features: fine and medium iron depletions
Amount: none to common
Hue: 10YR or 2.5Y
Value: 4 through 6 moist
Chroma: 1 through 3 moist
C horizon
Hue: 2.5Y.
Value: 4 or 5, 6 or 7 dry
Chroma: 3 through 6 moist or dry
Texture of fine earth: sand, loamy sand, fine sandy loam, loamy fine sand, fine sand, or sandy loam
Rock fragments: 0 to 3 percent gravel
Clay content: 2 to 12 percent
Reaction: strongly to slightly acid
Redoximorphic features: fine and medium iron-manganese masses in matrix, along root channels and along pores
Amount: few, common, or many
Hue: 5YR, 7.5YR, or 10YR
Value: 4 through 6
Chroma: 6 through 8
Redoximorphic features: fine and medium iron depletions
Amount: none to common
Hue: 10YR or 2.5Y
Value: 4 or 5
Chroma: 1 through 3
COMPETING SERIES: This is the
Maggodee and
Newport series. Maggodee soils are formed in piedmont terrain from alluvium and have Cg horizons.
Newport series formed in lodgemont till and have Cd horizons.
GEOGRAPHIC SETTING: Halfbluff soils are on marine terraces. Slopes are 0 to 9 percent. The soils formed in marine sediments derived from mixed sources. Elevations are 4 to 183 meters (10 to 600 feet). The climate is humid with cool, foggy summers and cool, wet winters. A strong marine influence limits the diurnal and annual range of temperature. The mean annual temperature is 11 to 13 degrees C (51 to 55 degrees F). The mean annual precipitation is 890 to 2285 millimeters (35 to 90 inches). The frost-free period is 275 to 325 days.
GEOGRAPHICALLY ASSOCIATED SOILS: This is the
Tepona series. Tepona soils occur under cool forested environments of
Sitka spruce and redwood, where the difference between mean summer and mean winter soil temperatures is less than 6 degrees C.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Moderately well drained; moderate runoff; saturated hydraulic conductivity is moderately high.
USE AND VEGETATION: This soil is used predominantly for pasture, recreation and urban development. Vegetation includes bentgrass, sweet vernalgrass, brome, common velvetgrass, hairy cat's ear and California blackberry.
DISTRIBUTION AND EXTENT: Coastal Redwood Belts; MLRA 4B. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Humboldt and Del Norte Counties Soil Survey, Northern Part, California, January 2010. The name is from a coastal bluff near Crescent City, California.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
1. Umbric epipedon - the zone from 0 to 46 centimeters (A & BA horizons).
2. Cambic horizon - the zone from 46 to 89 centimeters (Bw1 & Bw2 horizons).
3. Particle-size control section - the zone from 25 to 100 centimeters, averages 11 percent clay, and 55 percent fine sand and coarser, by weight.
4. Oxyaquic Dystrudepts - seasonal water table, aquic conditions for more than 30 days in most years within the zone from 89 to 152 centimeters (CB & C horizons)
ADDITIONAL DATA:
NSSL, Lincoln Lab sample number 08N0452
NASIS User Pedon ID 07CA605503
Soil classified using the 12th Edition of the Keys to Soil Taxonomy.
National Cooperative Soil Survey
U.S.A.