LOCATION CANOECREEK CATentative Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, isomesic Typic Haplustepts
TYPICAL PEDON: Canoecreek very gravelly loam on a northeast facing 63 percent slope under Douglas fir, tanoak and coast redwood at an elevation of 580 meters. (Colors are for dry soil unless otherwise stated) When described on June 21, 2005, the soil was moist throughout.
Oi--0 to 2 centimeters; 75 percent very dark brown (7.5YR 2.5/2) and 25 percent pinkish gray (7.5YR 6/2) slightly decomposed plant material, black (7.5YR 2.5/1) rubbed; about 75 percent fiber, 45 percent rubbed; moderately acid (pH 6.0); abrupt wavy boundary. (2 to 10 centimeters thick)
A1--2 to 10 centimeters; dark grayish brown (10YR 4/2) very gravelly loam, very dark brown (10YR 2/2) moist; moderate fine and very fine granular structure; soft, very friable, nonsticky and nonplastic; common very fine, few fine, common medium, and few coarse roots throughout; few medium and coarse tubular pores; 25 percent sandstone gravel and 25 percent gravel from conglomerate; moderately acid (pH 6.0); clear wavy boundary.
A2--10 to 23 centimeters; pale brown (10YR 6/3) very gravelly loam, very dark grayish brown (10YR 3/2) moist; moderate very fine and fine granular structure; slightly hard, very friable, nonsticky and nonplastic; common very fine, few fine, and common medium and coarse roots throughout; few fine, very fine, medium, and coarse tubular pores; 25 percent sandstone gravel and 25 percent gravel from conglomerate; slightly acid (pH 6.2); clear wavy boundary. (Combined thickness of the A horizons is 5 to 50 centimeters thick)
AB--23 to 45 centimeters; pale brown (10YR 6/3) very gravelly loam, dark brown (10YR 3/3) moist; moderate very fine and fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; common very fine, few fine, common medium and coarse roots throughout; few medium and coarse tubular pores; 25 percent sandstone gravel and 25 percent gravel from conglomerate; moderately acid (pH 6.0); gradual wavy boundary. (0 to 50 centimeters thick)
Bt1--45 to 90 centimeters; light yellowish brown (10YR 6/4) very gravelly loam, dark brown (10YR 3/3) moist; moderate very fine and fine granular structure; moderately hard, friable, slightly sticky and slightly plastic; common very fine, few fine, and common medium and coarse roots throughout; few very fine, fine, medium, and coarse tubular pores; few faint clay films on all faces of peds; 25 percent sandstone gravel and 25 percent gravel from conglomerate; slightly acid (pH 6.2); diffuse wavy boundary.
Bt2--90 to 135 centimeters; very pale brown (10YR 7/3) very gravelly loam, brown (10YR 4/3) moist; weak fine and medium subangular blocky structure parting to moderate very fine and fine granular; moderately hard, friable, slightly sticky and slightly plastic; common very fine, fine, medium, and coarse roots; common very fine tubular and few fine tubular pores; few faint clay films on rock fragments and on all faces of peds; 40 percent mudstone gravel and 10 percent gravel from conglomerate; moderately acid (pH 5.8); gradual wavy boundary.
Bt3--135 to 180 centimeters; very pale brown (10YR 7/3) extremely gravelly loam, brown (10YR 4/3) moist; moderate very fine and fine granular structure; hard, friable, slightly sticky and slightly plastic; few very fine and fine, and common medium and coarse roots throughout; few faint clay films on rock fragments and on all faces of peds; 60 percent mudstone gravel and 10 percent gravel from conglomerate; moderately acid (pH 5.8). (Combined thickness of the Bt or Bw horizons is 50 to 185 centimeters thick)
TYPE LOCATION: Humboldt County, California; located about 7 kilometers west of the town of Weott; USGS Bull Creek quadrangle, CA; 40 degrees 18 minutes 43 seconds north latitude and 124 degrees 0 minutes 24 seconds west longitude; UTM zone 10 414449mE, 4462857mN; NAD 83
RANGE IN CHARACTERISTICS:
Soil Temperature: The mean annual soil temperature at 50 centimeters is 9 to 11 degrees C. (48 to 51 degrees F) and the difference between mean summer and mean winter soil temperatures is less than 6 degrees C. The soil has an isomesic soil temperature regime.
Soil Moisture: The soil moisture control section is dry in some or all parts for 90 or more cumulative days in normal years and it is moist in some part for more than 180 cumulative days or for 90 or more consecutive days per year. The soil has an ustic soil moisture regime.
Surface Fragments: 0 to 14 percent gravel from conglomerate and 0 to 34 percent gravel, 0 to 5 percent cobbles, and 0 to 5 percent stones.
Particle size control section (weighted average):
Rock fragments: 35 to 60 percent strongly cemented sandstone, mudstone, and conglomerate gravel, 0 to 5 percent sandstone cobbles, 0 to 14 percent mudstone paragravel
Clay content: 15 to 26 percent
A horizons:
Hue: 10YR
Value: 4 through 6 dry, 2 through 4 moist
Chroma: 2 through 4 dry or moist
Rock fragments: 15 to 59 percent strongly cemented sandstone and mudstone, 0 to 34 percent indurated rounded gravel from conglomerate, 0 to 34 percent strongly cemented sandstone and mudstone cobbles, 0 to 5 percent strongly cemented sandstone stones, 0 to 14 percent mudstone paragravel
Clay content: 15 to 20 percent
Reaction: moderately or slightly acid
Bt or Bw horizons:
Hue: 7.5YR or 10YR
Value: 5 through 7 dry, 3 through 5 moist
Chroma: 2 to 6 dry or moist
Texture of fine earth: loam, sandy clay loam, or sandy loam
Rock fragments: 15 to 70 percent strongly cemented sandstone and mudstone, 0 to 35 percent indurated rounded gravel from conglomerate, 0 to 35 percent strongly cemented sandstone cobbles, 0 to 5 percent strongly cemented sandstone stones, 0 to 14 percent mudstone paragravel
Clay content: 15 to 25 percent
Reaction: strongly to slightly acid
Some pedons have C horizons:
Hue: 7.5YR or 10YR
Value: 5 to 7 dry, 4 or 5 moist
Chroma: 3 to 6 dry or moist
Texture of fine earth: loam, sandy loam, or loamy sand
Rock fragments: 35 to 90 percent strongly cemented subangular sandstone and mudstone and indurated rounded gravel from conglomerate, 0 to 35 percent strongly cemented subangular sandstone, mudstone, and conglomerate cobbles and stones
Clay content: 5 to 25 percent
Reaction: strongly to moderately acid
COMPETING SERIES: This is the Frenchman soil. Frenchman soils are formed in alluvium and are on river terraces. The Frenchman soil contains lithologic discontinuties in the profile.
GEOGRAPHIC SETTING: Canoecreek soils are on linear to concave or convex positions on summits, shoulders, and backslopes on mountain slopes and ridges. Slopes are 15 to 75 percent. Elevations are 185 to 730 meters. These soils formed in colluvium and residuum derived from sandstone, mudstone or conglomerate. The climate is humid with cool, foggy summers and cool, wet winters. Mean annual precipitation is 1525 to 3050 millimeters. The mean annual temperature is 10 to 12 degrees C. Frost free season is about 240 to 280 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Sproulish (T) and Redwohly (T) soils. Sproulish and Redwohly soils contain less than 35 percent rock fragments in the particle size control section. Redwohly soils have paralithic material between 50 and 100 centimeters. Sproulish soils are found on linear to concave or slightly convex positions on summits, shoulders and backslopes. Redwohly soils are found on convex to strongly convex positions on shoulders and summits.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained, high runoff, moderately high saturated hydraulic conductivity.
USE AND VEGETATION: This soil is used for timber production, wildlife habitat, and watershed. Natural vegetation includes Douglas-fir, tanoak, Pacific madrone, and evergreen huckleberry. When present, coast redwood is less than 50 percent of the total composition.
DISTRIBUTION AND EXTENT: Coastal Redwood Belt; MLRA 4B. The series is moderately extensive.
MLRA OFFICE RESPONSIBLE: Davis, California
SERIES PROPOSED: Humboldt and Del Norte Counties Soil Survey, Southern Part, California. Name is from a tributary creek to the Eel River.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
1. Ochric epipedon - the zone from 0 to 23 centimeters (Oe,A1 and A2 horizons). When mollic colors are present, the horizon is too thin to qualify as a mollic or umbric epipedon.
2. Cambic horizon - the zone from 23 to 180 centimeters (AB and Bt horizons).
3. Particle-size control section - the zone from 27 to 102 centimeters (AB, Bt1, and Bt2 horizons)
ADDITIONAL DATA:
Keys to Soil Taxonomy, 10th edition