LOCATION CARLAIN CAEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, superactive, isomesic Ultic Hapludalfs
TYPICAL PEDON: Carlain loam on a moderately sloping, south facing river terrace of 8 percent under redwood and Douglas-fir at 480 feet elevation. (Colors are for dry soil unless otherwise stated. When described on 1/23/80 the soil was moist throughout.)
Oi--1 inch to 0; litter of redwood and Douglas-fir.
A--0 to 5 inches; light brownish gray (10YR 6/2) loam, dark grayish brown (10YR 4/2) moist; strong fine subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common medium and few fine roots; few fine tubular and many fine interstitial pores; 5 percent hard rounded pebbles (2-10mm); strongly acid (pH 5.4); clear wavy boundary. (4 to 10 inches thick)
Bt1--5 to 12 inches; pale brown (10YR 6/3) loam, brown (10YR 5/3) moist; strong fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine, medium and coarse roots; many fine and common medium interstitial and few medium tubular pores; few thin clay films on faces of peds and lining pores; 5 percent hard rounded pebbles (2-10mm); strongly acid (pH 5.2); clear wavy boundary. (6 to 10 inches thick)
Bt2--12 to 19 inches; very pale brown (10YR 7/3) loam, yellowish brown (10YR 5/4) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine, medium and coarse roots; many fine and common medium interstitial and few medium tubular pores; common thin clay films on faces of peds and lining pores, few thin clay films bridging mineral grains; 5 percent hard rounded pebbles (2-10mm); strongly acid (pH 5.3), clear wavy boundary. (6 to 15 inches thick)
Bt3--19 to 29 inches; very pale brown (10YR 7/4) loam, light yellowish brown (10YR 6/4) moist; moderate fine and medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common fine, medium and coarse roots; many fine and common medium interstitial and few fine and medium tubular pores; many moderately thick clay films on faces of peds and lining pores; common thin clay films bridging mineral grains; 10 percent hard, rounded pebbles (2-15mm); strongly acid (pH 5.1); abrupt smooth boundary. (8 to 20 inches thick)
2Bt4--29 to 45 inches; light brown (7.5YR 6/4) extremely gravelly clay loam, strong brown (7.5YR 4/6) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; common very fine tubular and interstitial pores; continuous thick clay films on pebbles; 70 percent hard, rounded pebbles and 10 percent hard rounded cobbles (7.5-25cm); strongly acid (pH 5.3); gradual wavy boundary. (14 to 20 inches thick)
2Bt5--45 to 61 inches; light brown (7.5YR 6/4) extremely gravelly loam, brown (7.5YR 4/4) moist; massive; slightly hard, friable, slightly sticky and slightly plastic; few very fine roots; common very fine tubular and common very fine interstitial pores; many moderately thick clay films on pebbles; 65 percent hard, rounded pebbles and 5 percent hard rounded cobbles (75-250mm); strongly acid (pH 5.3).
TYPE LOCATION: Mendocino County, California; 20 feet north of the 19.35 mile marker on U.S. Hwy. 20; about 1675 feet south and 2200 feet east of the northwest corner of sec. 10, T.17N., R.15W., MDBM, Comptche SE quadrangle.
RANGE IN CHARACTERISTICS: Soil depth is greater than 60 inches. The mean annual soil temperature ranges from 50 to 55 degrees F. The difference between mean summer and mean winter soil temperature ranges from 3 to 9 degrees F. The soil between the depths of 8 to 19 inches is moist in all parts from November 1 to August 15 and is dry in some part from September 1 to October 1 in most years. The particle-size control section averages 18 to 25 percent clay and 5 to 25 percent coarse fragments.
The A horizon is 10YR 5/6, 6/2, 6/3 or 6/4. Moist color is 10YR 4/2, 4/3, 4/4 or 4/6. Clay content ranges from 10 to 20 percent. Gravel content ranges from 0 to 10 percent. Base saturation (sum) ranges from 60 to 75 percent. Reaction is strongly through slightly acid.
The Bt horizon is 10YR 6/3, 6/4, 7/3, 7/4; or 7.5YR 6/4. Moist color is 10YR 5/3, 5/4, 5/6, 6/4; 7.5YR 4/4 or 4/6. It is loam, sandy clay loam, clay loam, gravelly loam, gravelly sandy clay loam or gravelly clay loam. Clay content ranges from 18 to 32 percent. Coarse fragment content ranges from 2 to 35 percent.
The 2Bt horizon has colors the same as the Bt horizon. It is stratified, very or extremely gravelly loam, sandy loam, clay loam and sandy clay loam. Clay content ranges from 15 to 30 percent. Coarse fragment content ranges from 35 to 80 percent. Base saturation (sum) ranges from 35 to 65 percent. Reaction is strongly or moderately acid.
COMPETING SERIES: These are the Tramway (CA) and Irmulco (CA) series. Tramway soils are 20 to 40 inches deep to a paralithic contact. Irmulco soils have a paralithic contact between 60 and 80 inches and have less than 25 percent rock fragments throughout.
GEOGRAPHIC SETTING: Carlain soils occur on river terraces. Slopes are 2 to 9 percent. Elevations are 50 to 600 feet. The climate is characterized by cool foggy summers and cool moist winters. A strong marine influence limits the diurnal and annual range of temperature. Mean annual precipitation is 40 to 60 inches. Mean January temperature is about 50 degrees F., mean July temperature is about 55 degrees F. and the mean annual temperature is about 53 degrees F. The frost-free period is 290 to 365 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Irmulco and Tramway soils and the Dehaven, Frenchman, Gschwend, and Hotel soils. Dehaven and Hotel soils are on mountains and are skeletal. Frenchman and Gschwend soils occur on river terraces out of the zone of strong marine influence and have an ustic soil moisture regime.
DRAINAGE AND PERMEABILITY: Well drained; surface runoff under bare soil conditions is slow or medium; moderate permeability.
USE AND VEGETATION: Used for timber production, recreation and wildlife habitat. Vegetation consists of redwood, Douglas-fir, tanoak, huckleberry and oxalis.
DISTRIBUTION AND EXTENT: Northern coastal California. The series is not extensive. MLRA 4.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Mendocino County, California, Western Part, 1993.
REMARKS: The activity class was added to the classification in January of 2003. Competing series were not checked at that time. - ET
Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon -- the zone from 0 to 5 inches (A)
Argillic horizon -- the zone from 5 to 61 inches (BAt, Bt1, Bt2, 2Bt3, 2Bt4)