LOCATION WOODIN CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Typic Dystroxerepts
TYPICAL PEDON: Woodin extremely gravelly sandy loam - on a west facing convex slope of 75 percent under Douglas-fir, tanoak, and sugar pine at 1,450 feet elevation. (Colors are for dry soil unless otherwise stated. When described July 3, 1978, the soil was dry throughout.)
A1--0 to 2 inches; very dark brown (10YR 2/2) extremely gravelly sandy loam, black (10YR 2/1) moist; moderate very fine and fine granular structure; soft, very friable, nonsticky and nonplastic; common fine and very fine roots; many very fine and fine interstitial pores; 95 percent pebbles (2 to 75 mm); strongly acid (pH 5.4); abrupt smooth boundary. (1 to 2 inches thick)
A2--2 to 6 inches; very dark brown (10YR 2/2) extremely gravelly sandy loam, black (10YR 2/1) moist; strong very fine and fine granular structure; soft, very friable, nonsticky and nonplastic; many very fine, fine, and medium roots; many very fine and fine interstitial pores; 61 percent angular pebbles (2 to 75 mm); strongly acid (pH 5.4); clear smooth boundary. (2 to 4 inches thick)
Bw1--6 to 13 inches; very pale brown (10YR 7/4) extremely gravelly loam, dark yellowish brown (10YR 4/4) moist; strong very fine and fine granular structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine and fine and common medium, and coarse roots; many very fine, fine, and medium interstitial pores; few silt coatings on peds; 60 percent pebbles (2 to 75 mm), 5 percent cobbles; very strongly acid (pH 4.9); clear wavy boundary. (7 to 15 inches thick)
Bw2--13 to 22 inches; very pale brown (10YR 7/3) extremely gravelly loam, dark brown (10YR 3/3) moist; moderate fine subangular blocky structure; hard, firm, slightly sticky and slightly plastic; common very fine, and fine, and common medium and coarse roots; many fine and medium interstitial pores; few thin silt coatings on peds; 60 percent pebbles (30 to 75 mm), 10 percent cobbles (75 to 250 mm), and 2 percent stones; strongly acid (pH 5.3); abrupt irregular boundary. (9 to 20 inches thick)
R--22 inches; very hard fractured sandstone; fractures are less than 1 mm wide and are 6 to 30 cm apart; few very fine roots follow fractures; few thin silt coatings and manganese stains on rock faces. Rock does not slake in water.
TYPE LOCATION: Mendocino County, California; about 20 miles west on Fish Rock Road from the junction of Highway 128 and Fish Rock Road; about 20 feet west and 2,650 feet south of the northeast corner of section 35, T.12 N.; R.15 W., Ornbaun Valley Southwest Quadrangle, MDB&M.
RANGE IN CHARACTERISTICS: Depth to a lithic contact and thickness of the solum is 20 to 40 inches. The mean annual soil temperature is 54 to 59 degrees F. The soil between depths of 10 and 31 inches or lithic contact, whichever is shallower, is dry in all parts from July 1 to October 1, and is moist in all parts from November 1 to May 15 in most years. The particle-size control section averages from 18 to 25 percent clay and averages from 45 to 70 percent rock fragments.
The A horizon is 10YR 2/2, 3/2, 4/3, 5/2, 5/3, 5/4, 6/3, 6/4; 7.5YR 5/4 or 6/4. Moist color is 10YR 2/1, 2/2, 3/2, 3/3, 3/4, 4/2, 4/3; 7.5YR 5/4 or 6/4. It is gravelly sandy loam, very gravelly loam or extremely gravelly sandy loam. Clay content ranges from 15 to 25 percent. Gravel content ranges from 20 to 95 percent. Cobble content ranges from 0 to 10 percent. Reaction is very strongly acid through neutral. Base saturation (ammonium acetate) ranges from 50 to 80 percent.
The Bw horizon is 10YR 5/4, 5/6, 6/3, 6/4, 7/3, 7/4; 7.5YR 5/4, 5/6, 6/4 or 7/4. Moist color is 10YR 3/3, 3/4, 4/3, 4/4; 7.5YR 3/4, 4/4 or 5/6. It is very gravelly loam, sandy loam or sandy clay loam; extremely gravelly loam or sandy loam; or very cobbly loam or sandy loam. Clay content ranges from 15 to 25 percent. There is a slight increase in clay over the A horizon, but not enough to qualify for an argillic horizon. Gravel content ranges from 15 to 70 percent, cobble content ranges from 5 to 50 percent, and stone content ranges from 0 to 5 percent. Total rock fragment content ranges from 35 to 75 percent. Reaction is very strongly acid through medium acid. Base saturation (ammonium acetate) ranges from 20 to 55 percent.
COMPETING SERIES: These are the Atring (OR), Baldhill (WA), Barpeak (CA), Beekman (OR), Chamate (T OR), Clallam (WA), Farber (ID), Geppert (OR), Hartless (CA), Inskip (CA), Kanid (OR), Kindig (CA), Mayacama (CA), Neuns (CA), Sheetiron (CA), Straight (OR), Terbies (WA) and Vena (OR) soils. Atring, Clallam, Geppert and Inskip soils have a paralithic contact. Baldhill, Barpeak, Chamate, Farber, Hartless, Kanid, Kindig nd Terbies soils are more than 40 inches deep. Beekman soils have mean annual soil temperature of 47 to 54 degrees F. Mayacama soils are slightly acid or neutral throughout and have a moisture control section that is moist in all parts for only 135 consecutive days and is dry in all parts for 120 consecutive days. Neuns soils have a mean annual soil temperature of 47 to 53 degrees F and have a particle-size control section with 8 to 18 percent clay. Straight soils have a mean annual soil temperature of 47 to 52 degrees F and have soil color hues of 5YR and 2.5YR. Vena soils have a mean annual soil temperature of 47 to 52 degrees F and have a particle-size control section with less than 18 percent clay. Sheetiron soils have a MAST of 47 to 54 degrees F and are dry in the moisture control section for more than 90 days.
GEOGRAPHIC SETTING: The Woodin soils occur on hills and mountains. Slopes are 9 to 75 percent. Elevations are 500 to 4,250 feet. The soils are formed in material weathered from sandstone. The climate is subhumid with hot dry summers and cool moist winters. Mean annual precipitation ranges from 35 to 70 inches. Occasional snow occurs above 3,000 feet. Mean January temperature is about 48 degrees F;' and mean July temperature is about 68 degrees F. The mean annual temperature is about 55 degrees F. The frost-free season is 150 to 270 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Casabonne, Holman, Holohan, Hopland, Maymen, Ornbaun, Pardaloe, Wohly, and Yellowhound and Yorktree soils. Casabonne, Holohan, Ornbaun, Pardaloe, Yellowhound and Yorktree soils are over 40 inches deep. Holman, Hopland an Wohly soils have argillic horizons. Maymen soils are less than 20 inches deep.
DRAINAGE AND PERMEABILITY: Well drained, surface runoff under bare soil conditions is medium through very rapid; moderate permeability.
USE AND VEGETATION: This soil is used for limited commercial timber production, wildlife and watershed. Vegetation consists of Douglas-fir, tanoak, California nutmeg, sugar pine, madrone, and Canyon live oak.
DISTRIBUTION AND EXTENT: Northern coastal California. The series is not extensive. MLRA 5.
MLRA OFFICE RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Mendocino County, California, Eastern Part, 1985.
REMARKS; Diagnostic horizons and features recognized in this pedon are:
Cambic horizon - the zone from 6 to 22 inches (Bw1, Bw2 horizons)
Lithic contact - the boundary at 22 inches (R layer)