LOCATION CINDERFALL OR

Established Series
Rev. SJS-JVC-JBF
01/2011

CINDERFALL SERIES

The Cinderfall series consists of very deep, somewhat excessively drained soils that formed in volcanic ash over basaltic cinders. Cinderfall soils are on lava plains. Slopes are 1 to 8 percent. The mean annual precipitation is about 230 mm and the mean annual temperature is about 7 degrees C.

TAXONOMIC CLASS: Ashy-skeletal, glassy, frigid Vitritorrandic Haploxerolls

TYPICAL PEDON: Cinderfall ashy loamy sand--on a sloping plain at an elevation of 1,330 meters--rangeland. (Colors are for dry soil unless otherwise noted. When described on September 11, 2000, the soil was dry throughout.)

A1--0 to 8 cm; brown (10YR 5/3) ashy loamy sand, very dark grayish brown (10YR 3/2) moist; single grain; loose, very friable, nonsticky and nonplastic; few medium, many fine, and many very fine roots; many fine and very fine interstitial pores; about 35 percent very pale brown (10YR 7/3) medium to very coarse sand-size pumiceous ash grains; 5 percent gravel; neutral (pH 7.0); clear smooth boundary. (5 to 13 cm thick)

A2--8 to 25 cm; brown (10YR 5/3) ashy loamy sand, dark brown (10YR 3/3) moist; single grain; loose, very friable, nonsticky and nonplastic; common very fine and few fine roots; common fine and very fine interstitial pores; about 45 percent very pale brown (10YR 7/3) medium to very coarse sand-size pumiceous ash grains; 5 percent gravel; slightly alkaline (pH 7.6); clear smooth boundary. (13 to 38 cm thick)

A3--25 to 53 cm; brown (10YR 5/3) ashy loamy sand, dark brown (10YR 3/3) moist; moderate medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common fine and very fine roots; common very fine interstitial pores; 50 percent very pale brown (10YR 7/3) medium to very coarse sand-size pumiceous ash grains; 10 percent gravel; slightly alkaline (pH 7.8); clear smooth boundary. (20 to 60 cm thick)

2Cqk--53 to 157 cm; brown (10YR 5/3) extremely gravelly ashy sandy loam, dark yellowish brown (10YR 3/4) moist; massive; soft; slightly sticky and nonplastic; few fine roots; few very fine interstitial pores; 20 percent very pale brown (10YR 7/3) medium and coarse sand-size pumiceous ash grains; 65 percent gravel and 15 percent cobbles; few fine coats of opaline silica on tops of rock fragments; very slightly effervescent; secondary carbonates occurring as common fine coats on the tops and bottoms of rock fragments; slightly alkaline (pH 7.8); clear wavy boundary. (56 to 114 cm thick)

2Ck--157 to 173 cm; light brownish gray (10YR 6/2) extremely gravelly ashy fine sand, dark brown (10YR 3/3) moist; single grain; loose; nonsticky and nonplastic; common very fine roots; common very fine interstitial pores; about 35 percent very pale brown (10YR 7/3) medium to very coarse sand-size pumiceous ash grains; 70 percent gravel and 15 percent cobbles; secondary carbonates occurring as common fine coats on rock fragments; violently effervescent; moderately alkaline (pH 8.3).

TYPE LOCATION: Lake County, Oregon; about 1.0 mile west and 0.5 mile south of the town of Fort Rock; approximately 160 feet east and 3,427 feet south of the northwest corner of section 4, T. 26 S., R. 14 E.; USGS Fort Rock 7.5 minute topographic quadrangle; latitude 43 degrees 20 minutes 48 seconds N and longitude 121 degrees 04 minutes 26 seconds W NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually moist in winter and spring, dry in summer and fall; aridic moisture regime that borders on xeric.
Mean annual soil temperature: 7 to 8 degrees C.
Mollic epipedon thickness: 25 to 38 cm; includes the A1 and A2 horizons.
Depth to horizons with identifiable secondary carbonates: 50 to 75 cm.
Depth to contrasting textural stratification: 50 to 75 cm.
Volcanic glass content: 30 to 60 percent in coarse silt through fine sand fractions; 20 to 50 percent in medium sand through very coarse sand fractions.

Particle-size control section - Clay content: 5 to 15 percent.
Rock fragments: 35 to 60 percent, mainly gravel. Lithology of fragments is basaltic cinders.

A1 and A2 horizons
Value: 4 or 5 dry, 2 or 3 moist.
Chroma: 2 or 3, dry or moist.
Reaction: Neutral or slightly alkaline.
Organic matter content: 1 to 3 percent.

2Cqk horizon
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 through 4, dry or moist.
Texture: Extremely gravelly ashy fine sandy loam, extremely gravelly ashy sandy loam, extremely cobbly ashy fine sandy loam, extremely cobbly ashy sandy loam.
Rock fragments: 60 to 90 percent total with 50 to 65 percent gravel and 10 to 30 percent cobbles
Identifiable secondary carbonates and silica: Occurs as common fine coats occurring on the tops and bottoms of rock fragments.
Calcium carbonate equivalent: 1 to 3 percent.
Salinity (EC): 2 to 4 mmhos/cm
Sodicity (SAR): 1 to 12
Reaction: Slightly alkaline through strongly alkaline.

2Ck horizon
Value: 5 or 6 dry, 3 or 4 moist.
Chroma: 2 or 3, dry or moist.
Rock fragments: 60 to 90 percent total with 50 to 75 percent gravel and 10 to 30 percent cobbles
Identifiable secondary carbonates: Occurs as common fine coats on the tops and bottoms of rock fragments.
Calcium carbonate equivalent: 1 to 3 percent.
Salinity (EC): 2 to 4 mmhos/cm
Sodicity (SAR): 1 to 12
Reaction: Moderately alkaline or strongly alkaline.

COMPETING SERIES: These are the Cavin, Crackedground, Nutzan, and Wildcatbutte series.

Cavin soils have soil reaction of moderately acid or slightly acid in the epipedon, do not have basaltic cinders in the lower part of the particle-size control section, and do not have horizons with identifiable secondary carbonates. Crackedground soils are deep to lithic contacts and are dominated by stones in the particle-size control section. Nutzan soils are moderately deep to paralithic contacts. Wildcatbutte soils are dominated by cobbles in the particle-size control section.

GEOGRAPHIC SETTING: Cinderfall soils are on lava plains. They formed in volcanic ash over basaltic cinders. Slopes are 1 to 8 percent. Elevations range from 1,310 to 1,390 meters. The mean annual precipitation is 200 to 280 mm, the mean annual temperature is 6 to 7 degrees C., and the frost-free period is 50 to 80 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Abert, Kunceider, Lapham, and Morehouse soils. Abert soils are ashy, sodium-affected, and have ochric epipedons and cambic horizons. Kunceider soils are shallow to lithic contacts. Lapham soils are ashy over loamy-skeletal. Morehouse soils have ochric epipedons and have ashy loamy sand or ashy loamy fine sand textures to 100 cm.

DRAINAGE AND PERMEABILITY: Somewhat excessively drained; low surface runoff; moderately rapid permeability: high saturated hydraulic conductivity.

USE AND VEGETATION: Cinderfall soils are used for livestock grazing and wildlife habitat. The present vegetation is mountain big sagebrush, needleandthread, Idaho fescue, and western needlegrass.

DISTRIBUTION AND EXTENT: South-central Oregon. These soils are not extensive with about 900 acres of the series mapped to date. MLRA 23.

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

SERIES ESTABLISHED: Lake County (Northern Part), Oregon, 2006.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Mollic epipedon - The zone from the soil surface to 25 cm (A1 and A2 horizons).
Vitrandic intergrade feature - The zone from the soil surface to 76 cm (A1, A2, and A3 horizons and part of the 2Cqk horizon).
Identifiable secondary carbonates - The zone from 53 to 173 cm (2Cqk and 2Ck horizons).
Particle-size control section and ashy-skeletal substitute class with glassy mineralogy - The zone from 25 to 100 cm (A3 horizon and part of the 2Cqk horizon).

National Cooperative Soil Survey
U.S.A.