LOCATION MYSTERY                 CA

Established Series
Rev: ACF/JPS/SAA/ET
10/2016

MYSTERY SERIES

The Mystery series consists of very deep, moderately well-drained soils formed in multiple deposits of alluvium derived from mixed sources. Mystery soils are on gently sloping alluvial fans, fan remnants, and low terraces and have slopes 2 to 9 percent. Surface runoff is negligible to low. The mean annual precipitation is 1780 millimeters (70 inches) and the mean annual temperature is about 11 degrees C (52 degrees F).

TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, isomesic Oxyaquic Eutrudepts
TYPICAL PEDON: Mystery fine sandy loam - on a north-facing, linear slope of 2 percent under redwoods, tanoak, evergreen huckleberry, cascara, swordfern and redwood sorrel at 30 meters (100 feet) elevation. (Colors are for moist soil unless otherwise stated. When described October 17, 2005, the soil was moist throughout).

Oi--0 to 3 centimeters (0 to 1 inches); black (10YR 2/1) slightly decomposed needles, leaves and twigs, very dark grayish brown (10YR 3/2) dry; 95 percent unrubbed, 85 percent rubbed; loose, loose, nonsticky and nonplastic; many very fine and fine and common medium roots; many very fine and fine interstitial pores; 15 percent wood fragments; very strongly acid (pH 5.0); clear smooth boundary. (Thickness of the Oi horizon is 0 to 15 centimeters (0 to 6 inches))

A1--3 to 29 centimeters (1 to 11 inches); dark olive gray (5Y 3/2) fine sandy loam, light olive gray (5Y 6/2) dry; weak fine subangular blocky structure; soft, very friable, slightly sticky and slightly plastic; common fine, medium and coarse roots; common very fine tubular and interstitial pores; strongly acid (5.5 pH); abrupt smooth boundary.

2A2--29 to 43 centimeters (11 to 17 inches); very dark grayish brown (2.5Y 3/2) very fine sandy loam, grayish brown (2.5Y 5/2) dry; moderate very fine and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many fine and common very fine, medium, and coarse roots; common very fine and fine tubular and interstitial pores; strongly acid (5.5 pH); clear smooth boundary.

2A3--43 to 60 centimeters (17 to 24 inches); very dark grayish brown (2.5Y 3/2) very fine sandy loam, grayish brown (2.5Y 5/2) dry; moderate very fine and fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many medium and common very fine, fine, and coarse roots; common very fine and fine tubular and interstitial pores; moderately acid (6.0 pH); clear wavy boundary. (Combined thickness of A horizons is 25 to 75 centimeters (10 to 30 inches))

2C--60 to 77 centimeters (24 to 30 inches); dark grayish brown (2.5Y 4/2) fine sandy loam, light brownish gray (2.5Y 6/2) dry; massive; slightly hard, friable, slightly sticky and slightly plastic; many medium, common fine and coarse, and moderately few very fine roots; common very fine tubular and interstitial pores; moderately acid (6.0 pH); clear smooth boundary. (Thickness is 0 to 20 centimeters (0 to 8 inches))

3Bwb1--77 to 92 centimeters (30 to 36 inches); olive brown (2.5Y 4/3) very fine sandy loam, light olive brown (2.5Y 5/4) dry; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many medium and common very fine and fine roots; common very fine and fine tubular and interstitial pores; many very fine and fine distinct iron mass concentrations throughout soil matrix, yellowish brown (10YR 5/6) moist and common fine distinct iron depletions throughout matrix, gray (10YR 5/1) moist; moderately acid (6.0 pH); clear smooth boundary.

3Bwb2--92 to 104 centimeters (36 to 41 inches); olive brown (2.5Y 4/3) very fine sandy loam, light olive brown (2.5Y 5/4) dry; weak fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine and medium, and moderately few very fine roots; common very fine tubular and interstitial pores; common very fine and fine distinct iron mass concentrations throughout soil matrix, yellowish brown (10YR 5/6) moist and few very fine distinct iron depletions throughout matrix, gray (10YR 5/1) moist; moderately acid (6.0 pH); clear smooth boundary. (Combined thickness of the Bw horizons is 25 to 100 centimeters (10 to 39 inches))

4Ab--104 to 152 centimeters (41 to 60 inches); dark grayish brown (2.5Y 4/2) silt loam, light yellowish brown (2.5Y 6/3) dry; moderate fine and weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine and fine and moderately few medium roots; common very fine tubular and common very fine and fine interstitial pores; few very fine and fine distinct iron mass concentrations along root channels, yellowish brown (10YR 5/6) moist and few very fine distinct iron depletions along root channels, gray (10YR 5/1) moist; moderately acid (6.0 pH). (Thickness is 0 to 50 centimeters (0 to 20 inches))

TYPE LOCATION: Jedediah Smith Redwoods State Park, Del Norte County, California; located approximately 10 feet east of campsite 18 in the Jedediah Smith Redwoods State Park campground; southwest quarter, northeast quarter, Section 8, T.16N. R.1E.; WGS84 Decimal degrees 41.7910556 latitude and -124.0820833 longitude; HBLM, USGS Hiouchi Quadrangle, CA.; UTM Zone 10 409627mE 4627875mN; 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 77 to 100 centimeters (30 to 40 inches).

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.

Base Saturation, by ammonium acetate, is less than 60 percent between depths of 25 to 75 centimeters.

Particle-Size Control Section (weighted average):

Rock fragments: 0 to 15 percent gravel, 0 to 5 percent cobble, 0 to 2 percent stone.
Clay content: 10 to 16 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: 5 Y, 2.5Y, or 10YR.
Value: 3 through 6 dry, 2 through 4 moist.
Chroma: 1 through 4 dry and moist.

Texture of fine earth: very fine sandy loam or fine sandy loam.
Rock fragments: 0 to 15 percent gravel.
Clay content: 10 to 20 percent.
Reaction: moderately or strongly acid

Bw horizon

Hue: 2.5Y, 10YR, or 7.5YR.
Value: 4 through 7 dry, 2 through 5 moist.
Chroma: 2 through 6 dry, 2 through 4 moist.

Texture of fine earth: coarse sandy loam, fine sandy loam, very fine sandy loam, or sandy loam.
Rock fragments: 0 to 15 percent gravel; 0 to 5 percent cobbles; 0 to 2 percent stones.
Clay content: 5 to 20 percent.
Reaction: moderately or strongly acid

Redoximorphic features:

Amount: many, common, or few
Kind: very fine, fine and medium iron mass concentration and depletions in matrix or along root channels
Hue: 7.5YR, 10YR, or 2.5Y
Value: 4 through 6 moist
Chroma: 1 through 8 moist

C horizon

Range includes buried A horizons.

Hue: 2.5Y or 10YR.
Value: 4 through 7 dry, 2 through 6 moist.
Chroma: 2 through 4 dry and moist.

Texture of fine earth: stratified coarse sand through silt loam.
Rock fragments: 0 to 15 percent gravel, 0 to 5 percent cobbles, 0 to 5 percent stones.
Clay content: 0 to 22 percent.
Reaction: moderately or strongly acid

COMPETING SERIES: At this time there are no other series in this family.

GEOGRAPHIC SETTING: These soils are on gently sloping alluvial fans, low terraces, and fan remnants, and have slopes of 2 to 9 percent. Elevations are 2 to 205 meters (5 to 670 feet). These soils form in alluvium derived from mixed sources. The climate is humid with cool, foggy summers and cool, rainy winters. Mean annual precipitation is 1520 to 1900 millimeters (60 to 75 inches). Mean January temperature is about 8 degrees C; mean July temperature is about 13 degree C; and the mean annual temperature is 10 to 13 degrees C (50 to 55 degrees F). Frost free season is about 300 to 320 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Arlynda, Bigriver, and Bigtree soils. Arlynda soils have redoximorphic features near the surface and are fine-silty; they have less than 15 percent very fine sand to gravel sized particles in the particle size control section. Bigriver soils do not have redoximorphic features. Bigtree soils are fine loamy; they have more than 18 percent clay in the particle size control section. Arlynda soils are in depressions. Bigriver soils are found below Mystery in depositional areas where the velocity of floodwaters is relatively high, such as natural levee margins close to channels. Bigtree soils are found above Mystery where the velocity of floodwaters is relatively slow.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: moderately well drained; low runoff; moderately high saturated hydraulic conductivity, occasionally flooded.

USE AND VEGETATION: This soil has been used for commercial timber and is used for wildlife, recreation, and watershed. Natural vegetation consists of redwood, Douglas fir, western hemlock, tanoak, cascara, western thimbleberry, evergreen huckleberry, salmonberry, salal, and swordfern.

DISTRIBUTION AND EXTENT: MLRA 4B. The series is not extensive.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California

SERIES ESTABLISHED: Humboldt Del Norte area, California, 2007. The source of the name is from Trees of Mystery scenic area near Requa, California.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
1. Ochric epipedon - the zone from 0 to 29 centimeters(Oi and A1 horizons).
2. Cambic horizon - the zone from 77 to 152 centimeters (3Bwb1, 3Bwb2 and 4Ab horizons)
3. Particle-size control section - the zone from 25 to 100 centimeters, (2A2, 2A3, 3Bwb1, 3Bwb2) averages 15 percent clay, 41 percent fine sand or coarser, by weight, and 0 percent rock fragments by volume.
4. Oxyaquic Humudepts - seasonal water table, aquic conditions for more than 30 days in most years within the zone from 77 to 152 centimeters (3Bwb1, 3Bwb2 and 4Ab horizons)

Additional Data:

NASIS User Pedon ID: 05CA605REDW046

KSSL Pedon 06N0637Soil classified using the 12th Edition of the Keys to Soil Taxonomy. These soils were previously classified as Coarse-loamy, mixed, superactive, isomesic Oxyaquic Humudepts (2013), and changed back to original Coarse-loamy, mixed, superactive, isomesic Oxyaquic Eutrudepts (2007).

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National Cooperative Soil Survey
U.S.A.