LOCATION CHANCELAKES             OR

Established Series
Rev. CWL-MPK-JVC-JBF
01/2011

CHANCELAKES SERIES

The Chancelakes series consists of very deep, poorly drained soils that formed in lacustrine deposits derived from volcanic rock such as basalt and tuff with an influence of volcanic ash. Chancelakes soils are on depressions and drainageways on plateaus. Slopes are 0 to 2 percent. The mean annual precipitation is about 280 mm and the mean annual temperature is about 7 degrees C.

TAXONOMIC CLASS: Fine, smectitic, frigid Xeric Epiaquerts

TYPICAL PEDON: Chancelakes ashy silt loam--on a nearly level depression at an elevation of 1,525--rangeland. (Colors are for moist soil unless otherwise noted.)

AE--0 to 3 cm; dark grayish brown (10YR 4/2) ashy silt loam, light gray (10YR 7/1) dry; moderate thick platy structure parting to strong very thin platy; extremely hard, very firm, slightly sticky and slightly plastic; few very fine and common fine roots; few very fine and few fine vesicular pores; moderately alkaline (pH 8.1); abrupt smooth boundary. (3 to 8 cm thick)

B--3 to 25 cm; dark grayish brown (10YR 4/2) clay, brown (10YR 5/3) dry; strong fine prismatic structure parting to strong fine angular blocky; hard, firm, moderately sticky and very plastic; few very fine and few fine roots; few very fine and few fine tubular pores; common faint and few distinct clay films on faces of peds; few fine faint brown (10YR 4/3) masses of iron accumulation throughout; moderately alkaline (pH 8.4); clear smooth boundary. (33 to 25 cm thick)

Btk1--25 to 51 cm; dark grayish brown (10YR 4/2) clay, grayish brown (10YR 5/2) dry; moderate medium prismatic structure parting to strong fine and medium angular blocky; slightly hard, firm, moderately sticky and very plastic; few very fine roots; few very fine tubular pores; common faint and few distinct clay films on faces of peds; secondary carbonates segregated as 2 percent coarse coats on faces of peds; slightly effervescent; strongly alkaline (pH 8.5); gradual smooth boundary. (15 to 25 cm thick)

Btk2--51 to 74 cm; olive brown (2.5Y 4/3) clay, light brownish gray (2.5Y 6/2) dry; moderate medium subangular blocky structure with few wedge-shaped peds; slightly hard, very friable, moderately sticky and moderately plastic; few very fine roots; few very fine tubular pores; common faint clay films on faces of peds; secondary carbonates segregated as 6 percent fine to coarse coats on faces of peds; strongly effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (18 to 30 cm thick)

Btkss1--74 to 112 cm; dark grayish brown (2.5Y 4/2) clay loam, light brownish gray (2.5Y 6/2) dry; weak coarse prismatic structure parting to strong fine and medium angular blocky; hard, firm, moderately sticky and moderately plastic; few very fine roots; few very fine tubular pores; many intersecting slickensides; common pressure cutans on faces of peds; 25 percent fine distinct dark yellowish brown (10YR 4/4) masses of iron accumulation throughout; secondary carbonates segregated as common (6 percent) medium and coarse coats on faces of peds; strongly effervescent; moderately alkaline (pH 8.4); clear smooth boundary. (25 to 38 cm thick)

Btkss2--112 to 147 cm; dark brown (10YR 3/3) clay, pale brown (10YR 6/3) dry; strong fine angular blocky structure; hard, firm, moderately sticky and moderately plastic; few very fine roots; few very fine and few fine tubular pores; common intersecting slickensides; common pressure cutans on faces of peds; common medium prominent light yellowish brown (2.5Y 6/4) masses of iron accumulation and common faint very dark brown (7.5YR 2.5/2) masses of manganese accumulation throughout; secondary carbonates segregated as many (15 percent) coarse masses; violently effervescent; moderately alkaline (pH 8.4); abrupt smooth boundary. (0 to 36 cm thick)

B'tk--147 to 160 cm; dark grayish brown (10YR 4/2) with very dark brown (10YR 2/2) ashy sandy clay loam, light brownish gray (10YR 6/2) with dark grayish brown (10YR 4/2) dry; strong medium platy structure parting to moderate medium subangular blocky; slightly hard, very friable, moderately sticky and moderately plastic; few very fine roots; common very fine and few fine tubular pores; common prominent clay films on faces of peds; few medium prominent light yellowish brown (2.5Y 6/4) masses of iron accumulation throughout; secondary carbonates segregated as few fine coats on faces of peds; noneffervescent matrix and strongly effervescent coats; moderately alkaline (pH 8.2).

TYPE LOCATION: Lake County, Oregon; in Last Chance Lake about 30 miles north of the village of Christmas Valley; approximately 2,500 feet south 2,600 feet west of the northeast corner of section 3, T. 23 S., R. 18 E.; USGS Last Chance Lake 7.5 minute topographic quadrangle; latitude 43 degrees 36 minutes 33 seconds N and longitude 120 degrees 32 minutes 42 seconds W; NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: Ponded in winter and spring, dry in summer and fall; seasonal periods of aquic moisture regime during saturation with ground water and anaerobic conditions; xeric soil moisture regime.
Mean annual soil temperature: 7 to 8 degrees C.
Depth to horizons with aquic conditions: From the soil surface to a maximum depth of 25 cm.
Ochric epipedon thickness: 3 to 8 cm.
Abrupt textural change: An abrupt horizon boundary is normally present between the AE and Bt horizons accompanied by an absolute increase in clay content of more than 20 percent.
Depth to base of argillic horizon: 114 to more than 152 cm.
Other features: Cracking is present to the soil surface during the summer with wide cracks that become smaller with depth. The soil surface is not self-mulching.

Particle-size control section - Clay content: 35 to 60 percent.

AE horizon
Value: 6 or 7 dry, 4 or 5 moist.
Chroma: 1 or 2, moist or dry.
Reaction: Slightly alkaline or moderately alkaline
Volcanic glass content: 30 to 60 percent in coarse silt through fine sand fractions.
Redoximorphic features: Redox depletion of iron and/or clay is evident as the low chroma matrix.

Bt horizon
Hue: 10YR or 2.5Y.
Value: 5 through 7 dry.
Chroma: 2 through 4, moist or dry.
Texture: Clay, clay loam, or silty clay.
Clay content: 35 to 45 percent.
Redoximorphic features: Occurs as few faint redox concentrations of iron.
Reaction: Slightly alkaline through strongly alkaline.

Btk horizons
Hue: 10YR or 2.5Y.
Value: 5 through 7 dry.
Chroma: 2 through 4, moist or dry.
Texture: Clay, clay loam, or silty clay loam.
Clay content: 35 to 55 percent.
Reaction: Moderately alkaline or strongly alkaline.
Identifiable secondary carbonates: Occurs as fine to coarse masses or coats on faces of peds.
Calcium carbonate equivalent: 2 to 5 percent.
Salinity (EC): 2 to 4 mmhos/cm
Sodicity (SAR): 0 to 2

Btkss horizons
Hue: 10YR or 2.5Y.
Value: 5 through 7 dry.
Chroma: 2 through 4, moist or dry.
Texture: Clay, clay loam, or silty clay.
Clay content: 35 to 60 percent.
Vertic features: Occur as common or many intersecting slickensides on tops and bottoms of prisms or on wedge-shaped peds. Pressure cutans are present on vertical faces of prismatic and angular blocky peds.
Redoximorphic features: Redox concentrations occur as masses of iron and/or manganese accumulation. Some pedons have zones of iron depletion.
Identifiable secondary carbonates: Occurs as fine to coarse masses or as coats on faces of peds.
Calcium carbonate equivalent: 2 to 5 percent.
Salinity (EC): 2 to 4 mmhos/cm
Sodicity (SAR): 0 to 2
Reaction: Moderately alkaline or strongly alkaline.

B'tk horizon (when present)
Hue: 10YR or 2.5Y.
Texture: Ashy sandy clay loam or ashy clay loam.
Clay content: 30 to 40 percent.
Volcanic glass content: 20 to 40 percent in coarse silt through fine sand fractions.
Redoximorphic features: Redox concentrations occur as masses of iron and/or manganese accumulation. Redox depletion of iron is evident as the low chroma matrix.
Identifiable secondary carbonates: Occurs as few fine or medium masses or coats on faces of peds.
Calcium carbonate equivalent: 1 to 3 percent.
Salinity (EC): 2 to 4 mmhos/cm
Sodicity (SAR): 0 to 2
Reaction: Moderately alkaline or strongly alkaline.

COMPETING SERIES: This is the Boulder Lake series. Boulder Lake soils do not have albic horizons, argillic horizons, or ashy surface textures.

GEOGRAPHIC SETTING: Chancelakes soils are on depressions and drainageways on plateaus. These soils formed in lacustrine deposits derived from volcanic rocks such as basalt and tuff with an influence of volcanic ash. Slopes are 0 to 2 percent. Elevations range from 1,325 to 1,550 meters. The climate is semiarid with cold, moist winters and warm, dry summers. The mean annual precipitation is 250 to 300 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 Oatmanflat and Silverash soils. Oatmanflat soils are ashy, average 12 to 24 percent clay in the particle-size control section, do not have aquic conditions, and occur on stream terraces. Swalesilver soils do not have cracks to the soil surface, have shorter periods of surface ponding, and are on slightly higher parts of depressions.

DRAINAGE AND PERMEABILITY: Poorly drained; negligible surface runoff; very slow permeability; low saturated hydraulic conductivity. Episaturation is present with a perched seasonal high water table above 30 cm (very shallow and shallow free water occurrence classes) between January and May. Cumulative annual duration class is Common. These soils are susceptible to frequent ponding for long duration from January through May with water depths up to 30 cm. Endosaturation is also present in horizons below 74 cm between March and June.

USE AND VEGETATION: Chancelakes soils are used for livestock grazing and wildlife habitat. The vegetation is spike sedge, dock, and Baltic rush.

DISTRIBUTION AND EXTENT: South-central Oregon. These soils are not extensive with about 1,850 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:
Ochric epipedon and albic horizon - The zone from the soil surface to 3 cm (AE horizon).
Aquic conditions - The conditions of episaturation, reduction, and redoximorphic features between the soil surface and 25 cm at certain times during normal years (A and Bt horizons).
Argillic horizon - The zone from 3 to 147 cm (Bt, Btk1, Btk2, Btkss1, and Btkss2 horizons).
Abrupt textural change - The abrupt clay increase of more than 20 percent at 3 cm (between the A and Bt horizons).
Identifiable secondary carbonates - The zone from 25 to 160 cm (Btk1, Btk2, Btk221, Btkss2, and B'tk horizons).
Slickensides and vertic features - The zone from 74 to 147 cm (Btkss1 and Btkss2 horizons).
Particle-size control section - The zone from 25 to 100 cm (Btk1 and Btk2 horizons and part of the part of the Btkss1 horizon).

---

National Cooperative Soil Survey
U.S.A.