LOCATION BUNSELMEIER CAEstablished Series
TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, mesic Vitrandic Argixerolls
TYPICAL PEDON: Bunselmeier very gravelly sandy loam - on a northeast facing slope of 27 percent under a cover of mountain big sagebrush, antelope bitterbrush, scattered juniper, bluebunch wheatgrass and Thurber needlegrass at an elevation of 4,700 feet. (Colors are for dry soil unless otherwise stated. When described June 11, 1982, the soil was moist below 25 inches).
A--0 to 4 inches; brown (10YR 5/3) very gravelly sandy loam, very dark grayish brown (10YR 3/2) moist; strong coarse platy structure parting to moderate very fine subangular blocky; slightly hard, very friable, nonsticky and nonplastic; many very fine and common fine roots; many fine vesicular pores; 20 percent gravel sized cinders, 20 percent basalt gravel; neutral (pH 6.9); abrupt smooth boundary. (3 to 6 inches thick).
BA--4 to 12 inches; brown (10YR 5/3) very gravelly sandy loam, dark brown (10YR 3/3) moist; moderate fine subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; common very fine and few fine roots; many very fine tubular pores; 5 percent gravel sized cinders, 30 percent basalt gravel, 5 percent basalt cobbles; neutral (pH 6.9); clear wavy boundary. (7 to 8 inches thick).
Bt1--12 to 18 inches; brown (7.5YR 5/4) very gravelly sandy clay loam, dark brown (7.5YR 3/4) moist; moderate fine subangular blocky structure, slightly hard, very friable, slightly sticky and slightly plastic; few very fine, fine and medium roots; many very fine tubular pores; common thin clay films in pores; 35 percent gravel sized cinders, 5 percent cobble sized cinders; neutral (pH 6.9); abrupt wavy boundary, (6 to 9 inches thick).
Bt2--18 to 25 inches; strong brown (7.5YR 5/6) very gravelly sandy clay loam, dark brown (7.5YR 3/4) moist; weak very fine subangular blocky structure; hard, friable, slightly sticky and slightly plastic; few fine, medium, and coarse roots; common very fine tubular pores; many thin clay films in pores; 45 percent gravel sized cinders, 5 percent cobble sized cinders; neutral (pH 6.9); clear wavy boundary. (5 to 9 inches thick).
C1--25 to 30 inches; strong brown (7.5YR 5/6) extremely gravelly sandy loam, dark brown (7.5YR 3/4) moist; massive; hard, friable, nonsticky and nonplastic; few fine roots; many very fine tubular pores; 60 percent gravel sized cinders, 10 percent cobble sized cinders; neutral (pH 7.0); clear irregular boundary. (4 to 7 inches thick).
C2--30 to 40 inches; strong brown (7.5YR 5/6) extremely gravelly sandy loam, strong brown (7.5YR 4/6) moist; massive; hard, friable, nonsticky and nonplastic; few fine roots; many very fine tubular pores; 70 percent gravel sized cinders, 10 percent cobble sized cinders; neutral (pH 7.0); clear wavy boundary. (8 to 11 inches thick).
C3--40 to 48 inches; strong brown (7.5YR 5/6) extremely gravelly sandy loam, strong brown(7.5YR 4/6) moist; massive; soft; very friable nonsticky and nonplastic; few fine root; many very fine tubular pores; 93 percent gravel sized cinders; neutral (pH 7.0); clear irregular boundary. (7 to 10 inches thick).
C4--48 to 62 inches; cinders with 5 percent sandy loam filling interstices less than l mm wide.
TYPE LOCATION: Lassen County, California; about 11 miles southeast of Little Valley on a dirt road to Dixie Valley Ranch, 600 feet northwest of road to cinder pit; 500 feet east and 600 feet south of the northwest corner of sec. 36, T. 36 N., R. 8 E., Little Valley SE (Straylor Lake) quadrangle (7.5 minute series).
RANGE IN CHARACTERISTICS: Depth to unweathered cinders is 40 to 60 inches. Rock fragments, mostly gravel on the surface, ranges from 35 to 60 percent by volume. The particle size control section is from 12 to 32 inches. Glass content ranges from 5 to 10 percent.
The A horizon color is 10YR 5/3; 5YR 5/3. Moist color is 10YR 3/2; 7.5YR 3/2; 5YR 3/2. Organic matter ranges from 2 to 5 percent. Reaction ranges from neutral to mildly alkaline. Gravel content ranges from 35 to 60 percent by volume.
The BA horizon color is 10YR 5/3; 7.5YR 5/2. Moist color is 10YR 3/3; 7.5YR 3/2; 5YR 3/2. Gravel content ranges from 30 to 50 percent, cobble content is 5 to 10 percent by volume. Reaction is neutral to mildly alkaline.
The Bt horizon color is 7.5YR 5/4, 5/6, 4/4; 5YR 4/3. Moist color is 7.5YR 3/4; 5YR 4/4; 2.5YR 3/4. Clay content averages 20 to 30 percent. Gravel content is 30 to 45 percent, cobble content is 5 to 15 percent by volume. Reaction ranges from neutral to mildly alkaline.
The C horizon color is 7.5YR 5/6; 10YR 5/6; 5YR 4/6. Moist color is 7.5YR 3/4, 4/6; 5YR 4/4, 4/6; 2.5YR 4/4. Texture is extremely gravelly sandy loam. Gravel content is 55 to 95 percent, cobble content is 5 to 10 percent by volume.
Andic property data (see remarks for explanation):
Depth P-ret B.D. pH NaF Glass Alo Feo 15 barH20
0-4 19 1.05 ND ND 0.15 0.47 12.8
4-12 19 1.43 ND ND 0.16 0.42 16.4
12-18 27 0.99 ND ND 0.21 0.39 20.9
18-25 23 0.94 ND ND 0.18 0.29 18.5
25-30 8 NC ND ND 0.05 0.05 ND
30-40 ND ND ND ND ND ND ND
40-48 ND ND ND ND ND ND ND
48-62 ND ND ND ND ND ND ND
COMPETING SERIES: This is the Fleener (T CA), Hehe (OR), Leidl (T WA) and Skooker (OR) series. Fleener soils are greater than 60 inches deep to hard basalt bedrock, lack cinders and c horizons and have argillic horizons 31 to 54 inches thick. Hehe soils?????. Leidl soils?????. Skooker soils?????.
GEOGRAPHIC SETTING: Bunselmeier soils are on hills and cinder cones on the Modoc plateau. Slopes range from 15 to 30 percent. These soils formed in material mainly weathered from cinders. Elevation is 3,200 to 5,000 feet. The climate is semiarid with warm dry summers and cold moist winters. Mean annual precipitation varies from 12 to 16 inches. Snow fall is 12 to 24 inches. The mean annual temperature is 45 to 48 degrees F, the mean January temperature is about 41 degrees F; the mean annual July temperature is about 67 degrees F. Frost-free season is 80 to 100 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Jellycamp, Lassen, and Longcreek soils. Jellycamp soils are clayey and less than 20 inches deep to a duripan. Lassen soils are fine. Longcreek soils are clayey-skeletal and less than 20 inches deep to a lithic contact.
DRAINAGE AND PERMEABILITY: Well drained; slow to rapid runoff; moderately slow permeability.
USE AND VEGETATION: This soil is mainly used for rangeland. The natural vegetation is bluebunch wheatgrass, Thurber needlegrass, bottlebrush squirreltail, arrowleaf balsamroot, antelope bitterbrush, mountain big sagebrush and scattered western juniper.
DISTRIBUTION AND EXTENT: Northeastern Modoc Plateau in California. The soils are not extensive. MLRA is 21.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Lassen County, California, Intermountain Soil Survey Area, 1994. Source of name is from a spring.
REMARKS: The type location was moved to the Big Valley Soil Survey Area and reclassified. These soils are the oldest of the cinder cone sequence mapped in Big Valley soil survey area.
Diagnostic horizon and features recognized in this pedon are:
Mollic epipedon - the zone from the surface to a depth of about 12 inches (A, BA).
Argillic horizon - the zone from 12 to 25 inches (Bt1, Bt2).
Mineralogy - the clay fraction is dominated by halloysite. Gravel identified as cinders and makes up 56 percent of the soil by volume. More than 50 percent of the clay fraction was identified as halloysite by DTA. Lincoln laboratory data for the Bt2 showed the glass content as 7 percent.
Andic properties data defined and referenced in the soil taxonomy andisol amendment:
P-ret: phosphate retention of the less than 2mm fraction.
B.D.: bulk density of the less than 2mm fraction on an oven dry basis.
pH NaF: pH of soil mixed with saturated sodium floride solution.
Glass: percent volcanic glass.
Alo: acid-oxalate-extractable aluminum of the less than 2mm fraction.
Feo: acid-oxalate-extractable iron of the less than 2mm fraction.
15 bar H20: dried 1500 kPa water retention as a percent.
Data elements with a * are estimated.
The superactive cation exchange activity class was added in 03/2003 to the taxonomic classification by the National Soil Survey Center on request of the Reno MLRA office, without review of the soil series property data. The remainder of this document has not been updated.
NC: not calculated.
ND: not done.
Additional Data: A grab sample (Bt2) was sent to Lincoln and another private lab used by BLM. Pedon number is S83CA-35-1 and sample number is 7718, unpublished. UC Davis laboratory sample number 1691.
This pedon was characterized by UC Davis Laboratory, sample number, 88CA-089-05-(1-5) unpublished, Lab #1691.
The superactive cation exchange activity class was added in 03/2003 to the taxonomic classification by the National Soil Survey Center on request of the Reno MLRA office, without review of the soil series property data. The remainder of this document has not been updated.