LOCATION TATERPA OREstablished Series
TAXONOMIC CLASS: Coarse-loamy, mixed, superactive, frigid Pachic Haploxerolls
TYPICAL PEDON: Taterpa loam, on a 39 percent north-facing
slope, rangeland. (Colors are for moist soils unless
otherwise noted.)
A1--0 to 4 inches; black (10YR 2/1) loam, very dark
grayish brown (10YR 3/2) dry; weak medium granular
structure; soft, very friable, nonsticky and nonplastic;
many very fine and fine, and few medium roots; common very
fine and fine irregular pores; 5 percent gravel; neutral (pH
6.8); clear smooth boundary. (4 to 6 inches thick)
A2--4 to 13 inches; black (10YR 2/1) loam, very dark
grayish brown (10YR 3/2) dry; moderate fine subangular
blocky structure; soft, very friable, nonsticky and
nonplastic; many very fine and fine roots; common fine
continuous tubular pores; 10 percent gravel; neutral (pH
6.8); clear smooth boundary. (6 to 10 inches thick)
Bw1--13 to 25 inches; very dark brown (10YR 2/2) loam,
dark grayish brown (10YR 4/2) dry; moderate fine and medium subangular blocky structure; slightly hard, friable,
nonsticky and nonplastic; common very fine and fine roots;
common fine continuous tubular pores; 10 percent gravel;
neutral (pH 6.6); gradual smooth boundary. (9 to 17 inches
thick)
Bw2--25 to 34 inches; very dark grayish brown (10YR 3/2)
gravelly loam, brown (10YR 5/3) dry; moderate medium
subangular blocky structure; slightly hard, friable,
nonsticky and nonplastic; common very fine roots; common
fine continuous tubular pores; 20 percent gravel; slightly
acid (pH 6.4); clear smooth boundary. (8 to 12 inches
thick)
C1--34 to 41 inches; dark brown (10YR 3/3) gravelly
sandy loam, yellowish brown (10YR 5/4) dry; massive; hard,
firm, nonsticky and nonplastic; few very fine and fine
roots; few very fine and fine continuous tubular pores; 20
percent gravel; slightly acid (pH 6.2); clear smooth
boundary. (7 to 15 inches thick)
C2--41 to 49 inches; brown (10YR 4/3) gravelly sandy
loam, yellowish brown (10YR 5/4) dry; massive; slightly
hard, friable, nonsticky and nonplastic; few very fine
roots; few very fine discontinuous tubular pores; 30 percent
gravel; slightly acid (pH 6.2); clear wavy boundary. (5 to
11 inches thick)
Cr--49 inches; highly weathered quartz diorite.
TYPE LOCATION: Baker County, Oregon; located 900 feet north
and 100 feet west of the SE corner of sec. 14, T. 13 S., R.
42 E.
RANGE IN CHARACTERISTICS: These soils are usually moist,
but are dry in the moisture control section for 45 to 80
consecutive days following the summer solstice. The mean
annual soil temperature is 43 to 47 degrees F. Depth to
bedrock is 40 to 60 inches.
The A horizon has value of 2 or 3 moist, 3 or 4 dry and
chroma of 1 through 3 moist and dry. It has 0 to 10 percent
gravel.
The upper part of the Bw horizon has value of 2 or 3 moist,
4 or 5 dry and chroma of 2 or 3 moist and dry; and the lower
part has value of 2 or 3 moist, 4 or 5 dry and chroma of 2
through 4 moist and dry. It is loam, gravelly loam or sandy
loam, with 0 to 20 percent gravel and 10 to 15 percent clay.
The C horizon has value of 4 or 5 moist, 5 or 6 dry and
chroma of 3 or 4 moist and dry. It is gravelly sandy loam
or gravelly loamy sand, with 15 to 30 percent gravel.
COMPETING SERIES: These are the
Fren(T),
Iver,
Lobert,
Ola,
Redmount(T), and
Shively soils. Fren soils contain 15 to 30
percent ash to a depth of 25 inches and contain secondary
carbonates at 20 to 35 inches. Iver soils contain primarily
silty material in the upper part of the particle-size control
section and have a lithologic discontinuity at 27 to 38 inches. Lobert soils typically contain durinodes in the B horizon. Ola
soils are 20 to 40 inches to a lithic contact. Redmount soils
lack a cambic B horizon and have a very gravelly 2C horizon at 20
to 36 inches. Shively soils are mildly alkaline throughout the profile.
GEOGRAPHIC SETTING: Taterpa soils are on north-facing side
slopes of mountains. Elevations range from 4,000 to 6,200
feet. Slope is 12 to 60 percent. The soil is formed in
colluvium and residuum derived dominantly from quartz
diorite. The mean annual precipitation is 16 to 20 inches,
the mean annual air temperature is 40 to 45 degrees F, and
the frost-free period is 60 to 90 days.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Bouldrock,
Dogtown, and
Kilmerque soils. Bouldrock soils are
moderately deep and are on adjacent south slopes. Kilmerque
soils are moderately deep and are on adjacent forested south
slopes. Dogtown soils are loamy-skeletal and are on
adjacent forested north slopes.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is medium
to rapid. Permeability is moderate in the surface horizons
and moderately rapid in the subsoil.
USE AND VEGETATION: These soils are used for rangeland.
The native vegetation is Idaho fescue, bluebunch wheatgrass,
mountain big sagebrush and green rabbitbrush.
DISTRIBUTION AND EXTENT: Eastern Oregon. The series is of
moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Portland, Oregon
SERIES ESTABLISHED: Baker County Area, Oregon, 1988.
REMARKS: Diagnostic horizons and features in this pedon
are:
Mollic epipedon - the zone from the surface of the soil to a
depth of 34 inches (A1, A2, Bw1, Bw2 horizons).
"Pachic" feature - mollic epipedon to a depth of 34 inches.