LOCATION SEGUNDO            OR
Established Series
Rev. AEK/WEL/JAL
07/2001

SEGUNDO SERIES


The Segundo series consists of deep, well drained soils on mountains. They formed in colluvium derived dominantly from rhyolite and andesite. Slopes are 2 to 75 percent. The mean annual precipitation is about 20 inches, and the mean annual air temperature is about 42 degrees F.

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, frigid Typic Haploxerepts

TYPICAL PEDON: Segundo very gravelly loam, woodland. (Colors are for moist soil unless otherwise noted.)

Oi--0 to 1 inch; partially decomposed pine needles, grass and twigs.

A--1 to 6 inches; very dark brown (10YR 2/2) very gravelly loam, dark grayish brown (10YR 4/2) dry; weak fine granular structure; slightly hard, very friable, nonsticky and nonplastic; many very fine and fine roots; many very fine and fine irregular pores; 45 percent gravel; neutral (pH 7.2); clear wavy boundary. (3 to 9 inches thick)

Bw1--6 to 18 inches; brown (10YR 4/3) very gravelly loam, pale brown (10YR 6/3) dry; weak fine subangular blocky structure parting to weak fine granular; soft, very friable, nonsticky and nonplastic; many fine and few medium roots; many very fine and fine and few medium tubular pores; 35 percent gravel and 10 percent cobbles; neutral (pH 6.8); clear wavy boundary. (9 to 12 inches thick)

Bw2--18 to 22 inches; brown (10YR 5/3) very gravelly loam, very pale brown (10YR 7/3) dry; weak medium subangular blocky structure; soft, very friable, nonsticky and nonplastic; common fine and few medium roots; many fine and few medium tubular pores; 40 percent gravel and 10 percent cobbles; neutral (pH 7.0); clear wavy boundary. (4 to 12 inches thick)

2C1--22 to 41 inches; brown (10YR 5/3) very gravelly sandy loam, very pale brown (10YR 7/3) dry; massive; slightly hard, friable, nonsticky and nonplastic; common fine and medium roots; common fine tubular pores; 40 percent gravel and 10 percent cobbles; neutral (pH 7.0); gradual wavy boundary. (10 to 25 inches thick)

2C2--41 to 60 inches; multi-colored extremely gravelly loamy sand; massive; loose, nonsticky and nonplastic; 50 percent gravel, 15 percent cobbles and 5 percent stones; neutral (pH 7.0).

TYPE LOCATION: Baker County, Oregon; located about 2 miles
east of Dooley Mt. summit in the center of the
SW1/4NW1/4SE1/4 sec. 34, T. 11 S., R. 40 E.

RANGE IN CHARACTERISTICS: These soils are usually moist,
but are dry in the moisture control section for 45 to 60
consecutive days following the summer solstice. Depth to
bedrock is typically over 60 inches but is 40 to 60 in some
pedons.

The A horizon has value of 2 or 3 moist, 3 to 5 dry and
chroma of 2 or 3 moist and dry. It has 20 to 50 percent
gravel, 0 to 10 percent cobbles, and 0 to 15 percent stones.

The Bw horizon has value of 3 to 5 moist, 6 or 7 dry, and
chroma of 2 or 3 moist and dry. It has 35 to 60 percent
gravel, 0 to 15 percent cobbles, and 0 to 15 percent stones.
It is loam or sandy loam.

The 2C horizon has value of 5 or 6 moist, 5 to 7 dry, and
chroma of 2 to 4 moist and dry. It is loam, sandy loam, or
loamy sand.

COMPETING SERIES: These are the Ardenvoir, Blinn, Daxty,
Farva(T), Jumpe, Lostbasin, and Thout series. Ardenvoir,
Daxty, and Jumpe soils are dry for more than 60 consecutive
days following the summer solstice. Blinn soils lack value
of 5 dry in any part of the A horizon and are stony or very
stony throughout. Farva soils have a paralithic contact at
a depth of 20 to 40 inches. Lostbasin soils have 25 to 35
percent clay in the particle-size control section. Thout soils
are 20 to 40 inches deep to a lithic contact.

GEOGRAPHIC SETTING: Segundo soils are on south and
west-facing slopes and ridge tops of mountain slopes at
elevations of 4,000 to 6,000 feet. Slopes are 2 to 75
percent. The soil formed in colluvium derived dominantly
from rhyolite and andesite. The mean annual precipitation
is 16 to 30 inches. The mean annual temperature is 40 to 45
degrees F. The frost-free period is 50 to 90 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Anatone,
Baldridge, Inkler, and Stavely series. Anatone soils are
shallow. Baldridge soils have mollic epipedons. Inkler
soils have a volcanic ash surface horizon. Stavely soils
are nonskeletal.

DRAINAGE AND PERMEABILITY: Well drained. Runoff is slow to
rapid. Permeability is moderate in the upper 20 to 30
inches and moderately rapid in the lower part.

USE AND VEGETATION: These soils are used for woodland,
watershed, and wildlife habitat. The native vegetation is
ponderosa pine, Douglas fir, elk sedge, pinegrass, Idaho
fescue, snowberry, spirea, antelope bitterbrush, heartleaf
arnica, and wild strawberry.

DISTRIBUTION AND EXTENT: Northeastern Oregon. The series
is of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Bozeman, Montana

SERIES ESTABLISHED: Baker County Area, Oregon; 1988.

REMARKS: Diagnostic horizons and features in this pedon
are:

Cambic horizon - the zone from 5 to 21 inches (Bw1 and Bw2).


National Cooperative Soil Survey
U.S.A.