LOCATION PAULINA                 OR

Established Series
Rev. RJK-MPK-JVC-JBF
05/2011

PAULINA SERIES

The Paulina series consists of very deep, very poorly drained soils that formed in alluvium derived from volcanic rocks, volcanic ash, and pumice. Paulina soils are on flood plains or lakebeds. Slopes are 0 to 1 percent. The mean annual precipitation is about 230 mm and the mean annual temperature is about 7 degrees C.

TAXONOMIC CLASS: Ashy, glassy, frigid Aquandic Endoaquolls

TYPICAL PEDON: Paulina ashy mucky silt loam--on a one percent slope at an elevation of 1,317 meters--pastureland. (Colors are for moist soil unless otherwise noted. When described on August 17, 1998 the soil was moist to 30 cm, saturated from 30 to 51 cm, and a water table was present below 51 cm.)

Oe--0 to 3 cm; very dark grayish brown (10YR 3/2) moderately decomposed plant material, brown (10YR 4/3) dry; massive; soft, friable, slightly sticky and nonplastic; about 30 percent fibers after rubbing which are dead roots and stems of grass and grass-like plants; many very fine roots; abrupt smooth boundary. (0 to 8 cm thick)

A1--3 to 8 cm; black (10YR 2/1) ashy mucky silt loam, dark grayish brown (10YR 4/2) dry; moderate fine and medium granular structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, many fine, and many medium roots; many very fine and many fine tubular pores; slightly alkaline (pH 7.8); abrupt smooth boundary. (5 or 8 cm thick)

A2--8 to 30 cm; black (10YR 2/1) ashy silty clay loam, gray (10YR 5/1) dry, moderate fine and medium granular structure; hard, firm, moderately sticky and moderately plastic; many very fine, many fine, and many medium roots; many very fine and fine tubular pores; slightly alkaline (pH 7.8); abrupt smooth boundary. (20 to 43 cm thick)

C1--30 to 46 cm; dark grayish brown (10YR 4/2) ashy loam, light brownish gray (10YR 6/2) dry; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; many very fine, many fine, and many medium roots; many fine and medium tubular pores; common fine faint brown (10YR 4/3) masses of iron accumulation; slightly alkaline (pH 7.6). (8 to 18 cm thick)

C2--46 to 64 cm; dark gray (10YR 4/1) ashy loam, light gray (10YR 7/1) dry; weak medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic; common very fine, common fine, and common medium roots; many fine and medium tubular pores; common fine distinct brown (10YR 4/3) masses of iron accumulation; slightly alkaline (pH 7.6). (13 to 38 cm thick)

C3--64 to 135 cm; dark grayish brown (10YR 4/2) ashy very fine sandy loam, light gray (10YR 7/1) dry; massive; slightly hard, very friable, slightly sticky and nonplastic; few very fine, few fine, and few medium roots; common very fine and common fine tubular pores; common fine distinct dark yellowish brown (10YR 4/4) masses of iron accumulation; slightly alkaline (pH 7.6). (13 to 75 cm thick)

C4--135 to 152 cm; dark grayish brown (10YR 4/2) ashy loam, white (10YR 8/1) dry; massive; hard, friable, slightly sticky and slightly plastic; few fine and few medium roots; few fine tubular pores; many fine distinct dark yellowish brown (10YR 4/4) masses of iron accumulation and many fine prominent dark gray (N 4/) zones of iron depletion; slightly alkaline (pH 7.6).

TYPE LOCATION: Lake County, Oregon; in Paulina Marsh about 2.5 miles north-northeast of the community of Silver Lake; approximately 500 feet north and 250 feet east of the southwest corner of section 2, T. 28 S., R. 14 E.; USGS Silver Lake 7.5 minute topographic quadrangle; latitude 43 degrees 9 minutes 54.4 seconds N and longitude 121 degrees 2 minutes 0.8 seconds W; NAD 83.

RANGE IN CHARACTERISTICS:
Soil moisture: Usually wet in winter and spring; moist to wet in summer and fall; aquic moisture regime.
Mean annual soil temperature: 7 to 8 degrees C.
Mollic epipedon thickness: 25 to 50 cm.
Depth to aquic conditions: 0 to 46 cm.
Depth to redoximorphic features: 25 to 50 cm.
Reaction: Neutral or slightly alkaline.
Other features: It is assumed that enough active ferrous iron occurs in the A and upper C horizons, when aquic conditions are present, to give positive reactions to alpha, alpha-dipyridyl.

Particle-size control section - Clay content: Averages 18 to 30 percent.
Volcanic glass content: 60 to 80 percent in coarse silt through fine sand fractions.

O horizon (when present)
Texture: Slightly decomposed or moderately decomposed plant material.
Rubbed fiber content: 25 to 80 percent composed of parts of grass and grass-like plants.
Other features: Where it occurs, this horizon is too thin to be a histic epipedon.

A1 horizon
Value: 2 or 3 moist, 4 or 5 dry.
Chroma: 1 through 3, moist or dry.
Organic matter content: 4 to 12 percent.

A1 horizon
Value: 2 or 3 moist, 4 or 5 dry.
Chroma: 1 through 3, moist or dry.
Texture: Ashy mucky silt loam, ashy silt loam, or ashy silty clay loam.
Clay content: 18 to 30 percent.
Organic matter content: 4 to 12 percent.

C horizons
Value: 3 through 5 moist, 6 through 8 dry.
Chroma: 1 or 2, moist or dry.
Texture: Stratified ashy very fine sandy loam to ashy silty clay loam.
Clay content: 12 to 32 percent.
Structure: Weak subangular blocky or massive.
Redoximorphic features: Redox concentrations occur as masses of iron accumulation; redox depletions occur as zones of iron depletion.

COMPETING SERIES: These are the Four Star and Middleres series.

Four Star soils have mollic epipedons 60 to 122 cm thick and average 7 to 18 percent clay in the particle-size control section. Middleres soils have ashy sandy textures in the lower part of the particle-size control section.

GEOGRAPHIC SETTING: Paulina soils are on flood plains or lakebeds. These soils formed in alluvium derived from volcanic rocks, volcanic ash, and pumice. Slopes are 0 to 1 percent. Elevations range from 1,220 to 1,525 meters. The climate is semiarid and characterized by cold, moist winters and warm, dry summers. The mean annual precipitation is 200 to 360 mm, the mean annual temperature is 6 to 7 degrees C., and the frost-free period is 40 to 80 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Bonnick, Chinarise, Embal, Morehouse, and Tuffcabin soils. Bonnick, Embal, Morehouse and Tuffcabin soils lack a seasonal high water table. Chinarise soils have a seasonal high water table at 60 to 100 cm.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Very poorly drained; negligible surface runoff; moderately high saturated hydraulic conductivity. Endosaturation is present with an apparent seasonal high water table between the soil surface and 46 cm (very shallow and shallow free water occurrence classes) from January to June. Water levels may drop as low as 100 cm between July and December. Cumulative annual duration class is Permanent. Some phases are susceptible to frequent ponding for very long duration during February and March with water up to 15 cm deep. Some phases adjacent to streams are susceptible to frequent flooding for long periods between March and June.

USE AND VEGETATION: Paulina soils are used for livestock grazing, hay production, and wildlife habitat. The vegetation is mainly tufted hairgrass, Nebraska sedge, rush, and meadow foxtail.

DISTRIBUTION AND EXTENT: South-central Oregon. These soils are not extensive with about 9,600 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. The series was first proposed in Lake County, Oregon in 1962.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Organic soil material - The zone from the soil surface to 3 cm (Oe horizon).
Mollic epipedon - The zone from 3 to 30 cm (A1 and A2 horizons).
Vitrandic intergrade feature - The zone from 3 to 79 cm (A1, A2, C1, and C2 horizons and part of the C3 horizon).
Aquic conditions - The conditions of endosaturation, reduction, and redoximorphic features between the soil surface and 152 cm at certain times during normal years (parts of the Oe, A1, A2, C1, C2, C3, and C4 horizons).
Particle-size control section and ashy substitute class with glassy mineralogy - The zone from 25 to 100 cm (C1 and C2 horizons and parts of the A2 and C3 horizons).

ADDITIONAL DATA: Volcanic glass in the C3 horizon determined locally by optical grain count using a polarizing petrographic microscope.

---

National Cooperative Soil Survey
U.S.A.