LOCATION GAVEL CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, isotic, mesic Vitrandic Argixerolls
TYPICAL PEDON: Gavel stony loam on a 7 percent NE facing slope under Jeffrey pine, bitterbrush, western juniper, and squirreltail at 5,050 feet elevation. (When described May 4, 1982 the soil was slightly moist from 0 to 4 inches and moist below 4 inches. Colors are for dry soil unless otherwise stated.)
0--1.5 inch to 0; loose, fresh and partially decomposed mat of needles, twigs, and pine cones; abrupt smooth boundary.
A1--0 to 4 inches; reddish brown (5YR 5/3) stony loam, dark reddish brown (5YR 3/2) moist; medium very fine and fine granular structure; soft, very friable, slightly sticky and slightly plastic; many very fine and fine roots; many very fine interstitial and common very fine tubular pores; 3 percent stones, 5 percent cobbles, and 25 percent pebbles; slightly acid (pH 6.1); clear wavy boundary.
A2--4 to 12 inches; reddish brown (5YR 4/4) very gravelly loam, dark reddish brown (5YR 3/3) moist; moderate fine and medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine, common fine and few medium roots; many very fine interstitial and tubular pores; 5 percent cobbles composed of weathered andesite, and 30 percent pebbles; slightly acid (pH 6.5); clear wavy boundary. (The combined thickness of the A horizon is 8 to 15 inches)
Bt1--12 to 18 inches; reddish brown (5YR 4/4) very gravelly loam, dark reddish brown (5YR 3/3) moist; moderate fine and medium subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many very fine, common fine and few medium roots; many very fine interstitial and tubular pores; 5 percent cobbles composed of weathered andesite, and 45 percent pebbles; slightly acid (pH 6.5); clear wavy boundary.
Bt2--18 to 27 inches; yellowish red (5YR 4/6) very gravelly loam, dark reddish brown (5YR 3/4) moist; moderate fine and medium angular blocky structure; slightly hard, very friable, sticky and plastic; common very fine, fine and medium roots; many very fine interstitial and tubular pores; common thin clay films bridging sand grains and in pores; 5 percent cobbles composed of weathered andesite, and 40 percent pebbles; slightly acid (pH 6.5); abrupt wavy boundary. (The combined thickness of the Bt horizon is 12 to 26 inches)
Cr--27 to 70 inches; soft weathered andesite, slightly fractured in upper 6 inches, few pockets of medium roots, pockets of clay films appear weathered in place.
TYPE LOCATION: Lassen County, California: about 8 miles NW of Susanville; from the intersection of Highway 139 and Rice Canyon Road, 0.5 miles S on Rice Canyon Road then E on trail 0.28 miles to fork; site is between forks, 40 feet from their confluence and 10 feet S of the N fork; 370 feet W and 1,650 feet S of NE corner of sec. 8, T. 30 N., R 13 E.
RANGE IN CHARACTERISTICS: The thickness of the solum and depth to a paralithic contact is 20 to 40 inches. The mean annual soil temperature is 47 to 52 degrees F. The soil moisture control section (9 to 30 inches or the paralithic contact) is moist in all parts from December 1 to May 1. It is dry in all parts from July 15 to November 1 (107 days). The soil temperature exceeds 41 degrees F from April 15 to December 1 and exceeds 47 degrees F from May 15 to November 1. The mollic epipedon is 8 to 18 inches thick and in some pedons includes part of the B horizon. Reaction is slightly acid or neutral. Rock fragments on the surface, mostly cobbles and gravel, range from 15 to 25 percent. Base saturation (by sum of cations) between the depth of 10 to 30 inches ranges from 60 to 75 percent.
The A horizon is 7.5YR 4/2, 4/4, 5/2; and 5YR 4/2, 4/4, 5/2 or 5/3. Moist color is 7.5YR 3/2; 5YR 3/2 or 3/3. It is stony loam or gravelly loam with 10 to 20 percent clay. Rock fragments, mostly cobbles and gravel, range from 15 to 35 percent.
The Bt horizon is 7.5YR 5/2; 5YR 4/4, 4/6, 5/2, 5/3 or 5/4. Moist color is 7.5YR 3/2, 3/4; 5YR 3/3 or 3/4. It is very cobbly loam or very gravelly loam with 20 to 27 percent clay. Rock fragments, mostly cobbles and gravel, range from 35 to 50 percent.
COMPETING SERIES: These are the Bluenose, Bluesprin, Bobbitt, Fordice (T), Jellico (T), Keuterville, Nashmead, Sallyann, Tekoa, and Vilot (T) series. The Bluesprin, Bobbitt, Jellico and Sallyann soils are 20 to 40 inches deep to a hard, lithic contact. Nashmead soils are 40 to 60 inches deep. Bluenose, Fordice and Keuterville soils are greater than 60 inches deep. Tekoa soils have loam and silt loam textures in the fine-earth fraction of the subsoil, have C horizons, are influenced by loess and are dry for 60 to 80 consecutive days. Vilot soils have control sections with 50 to 80 percent rock fragments and 27 to 35 percent clay. In addition, the A horizon is very strongly through medium acid and the B horizon is very strongly or strongly acid.
GEOGRAPHIC SETTING: Gavel soils are on sideslopes of hills and mountains, mostly on northerly aspects. Slopes are 5 to 30 percent. The soils formed in material weathered from andesite or basalt. Elevation is 4,800 to 5,400 feet. The climate is semi arid with warm, dry summers and cold, moist winters (no rainfall). The mean annual temperature varies from 44 to 46 degrees F. Mean July temperature varies from 64 to 68 degrees F and mean January temperature varies from 24 to 28 degrees F. Frost free season is 80 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Gooch (T), Longcreek (T), and Petescreek (T) soils. Gooch soils are shallow and have clay subsoils. Longcreek soils are shallow and have very cobbly clay subsoils. Petescreek soils have a mean annual soil temperature less than 47 degrees F.
DRAINAGE AND PERMEABILITY: Well drained, medium to rapid runoff; moderate permeability.
USE AND VEGETATION: Gavel series are used for timber production and livestock grazing. Vegetation is Jeffrey pine and western juniper with an understory of bitterbrush, mountain mahogany, mountain big sagebrush, Columbia needlegrass, and Idaho fescue.
DISTRIBUTION AND EXTENT: Northeastern California. The soils are not extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES PROPOSED: Susanville Area, Lassen County, California 1984. Name is coined.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon-The zone from the surface to a depth of 18 inches (A1, A2, Bt1).
Argillic horizon-The zone from about 12 to 27 inches (Bt1, Bt2).
Paralithic contact-27 inches.