Soil Survey Manual - Appendix 1
Three appendices are included. The first gives examples of descriptions of
soil series. The second appendix describes three map units that are quite different in
their systematics. The third appendix contains point information for soils of
the three map units.
Series Data
Sharpsburg Official Soil Series Description
The Sharpsburg series consists of deep, moderately well drained soils formed
in loess on uplands. Permeability is in the moderately high saturated hydraulic
conductivity class. The lower part of the subsoil is more permeable than the
upper part. Slope ranges from 0 to 18 percent. Mean annual temperature is about
11 °C, and mean annual precipitation is about 750 mm.
Taxonomic Class: Fine, montmorillonitic, mesic Typic Argiudolls
Representative Pedon: Sharpsburg silty clay loam with a convex slope of 8
percent-cultivated. Colors are for moist soil unless otherwise stated.
Ap—0 to 20 cm; black (10YR 2/1) silty clay loam, dark grayish brown (10YR
4/2) dry; weak fine subangular blocky structure; friable; few fine roots;
slightly acid; abrupt smooth boundary.
A1—20 to 28 cm; very dark brown (10YR 2/2) silty clay loam, dark grayish
brown (10YR 4/2) dry; moderate very fine subangular blocky structure; friable;
slightly acid; clear smooth boundary.
A2—28 to 43 cm; very dark grayish brown (10YR 3/2) silty clay loam, grayish
brown (10YR 5/2) dry; some brown (10YR 4/3) peds; moderate very fine subangular
blocky structure; friable; moderately acid; gradual smooth boundary. Combined
thickness of the A horizons is 25 to 60 cm.
Bt1—43 to 61 cm; brown (10YR 4/3) silty clay loam; very dark gray (10YR 3/1)
coatings on faces of peds; moderate fine subangular blocky structure parting to
weak fine subangular blocky; firm; common distinct very dark grayish brown (10YR
3/2) clay films; very few fine roots; moderately acid; gradual smooth boundary.
Bt2—61 to 79 cm; brown (10YR 4/3) and yellowish brown (10YR 5/4) silty clay
loam; few fine prominent light brownish gray (2.5Y 6/2) mottles; weak medium
prismatic structure parting to moderate fine subangular blocky; firm; many
distinct dark grayish brown (10YR 4/2) clay films; very few fine and medium
roots; few fine dark concretions (iron and manganese oxides); moderately acid;
gradual smooth boundary.
Bt3—79 to 97 cm; brown (10YR 5/3) silty clay loam; common medium distinct
light brownish gray (2.5Y 6/2) and strong brown (7.5YR 5/6) mottles; weak medium
prismatic structure parting to weak medium subangular blocky; friable; many
prominent grayish brown (10YR 5/2) clay films; few fine dark concretions (iron
and manganese oxides); moderately acid; gradual smooth boundary. Combined
thickness of the Bt horizons is 53 to 97 cm.
BC—97 to 117 cm; yellowish brown (10YR 5/4) silty clay loam; many fine and
medium distinct grayish brown (2.5Y 5/2) and common medium prominent strong
brown (7.5YR 5/8) mottles; weak medium prismatic structure; firm; common
distinct grayish brown (10YR 5/2) clay films; few fine dark concretions (iron
and manganese oxides); moderately acid; gradual smooth boundary. (10 to 25 cm
thick)
C—117 to 152 cm; mottled grayish brown (2.5Y 5/2), yellowish brown (10YR
5/4), strong brown (7.5YR 4/4) silty clay loam; massive; firm; very few fine
roots; common fine dark concretions (iron and manganese oxides); slightly acid.
Type Location: Taylor County, Iowa; about 13 km north and 8 km east of
Bedford; 570 m east and 165 m south of the northwest corner, sec. 10, T. 69 N.,
R. 33 W.
Range in Characteristics: Solum thickness typically is 90 to 180 cm thick.
Thickness of the A horizon, depth to clay maximum, maximum percent clay,
thickness of the Bt horizon, depth to grayish mottles, and solum thickness
decrease as gradient increases on convex slopes. The solum is moderately acid or
strongly acid in the most acid part.
The Ap horizon has value of 2 or 3 and chroma of 1 or 2. The A1 and A2
horizons have value and chroma of 2 or 3. The A horizon ranges from 25 to 34
percent clay.
The upper part of the Bt horizon has value of 4 or 5, and chroma of 3 or 4
and contains 36 to 42 percent clay. Pedons having colors in the matrix of 5 or 6
value and 2 chroma at depths of less than 80 cm are outside the range.
The lower part of the Bt horizon, the BC horizon, and the C horizon have hue
of 7.5YR to 5Y, value of 4 through 6, and chroma of 2 through 6. The C horizon
is silty clay loam or silt loam.
Competing Series: These are the Gymer, Oska, and Polo series. Similar soils
are the Grundy, Macksburg, and Wymore soils. Gymer and Oska soils have 7.5YR or
5YR hue in the Bt horizon. In addition, Oska soils have a lithic contact within
depths of 100 cm. Polo soils have 7.5YR and 5YR hue in the lower part of the B
horizon. Grundy and Macksburg soils have lower chroma, mottles, or both in the
upper part of the B horizon. Also, Grundy soils have 42 to 48 percent clay in
the upper 50 cm of the argillic horizon. Wymore soils have 2.5Y or yellower hue,
dominant chroma of 2 in the B horizon, and contain more clay.
Geographic Setting: Sharpsburg soils are on convex ridgetops, and convex side
slopes, and on high benches. Typically, they are on narrow ridgetops having
slopes of 2 to 9 percent gradient. The full range of slope is from 0 to 18
percent. Sharpsburg soils formed in 2 to 5 meters of loess that contains less
than 5 percent sand. Mean annual temperature ranges from about 8 to 14 °C and
mean annual precipitation ranges from about 700 to 800 mm.
Geographically Associated Soils: The somewhat poorly drained Macksburg soils
and the poorly drained Winterset soils form a drainage sequence with the
Sharpsburg soils and commonly are on the more nearly level parts of the
landscape. Adair, Clarinda, Lamoni, Pawnee, and Shelby soils are on adjoining
lower parts of the landscape. They formed in till or in paleosols formed in
till. Judson, soils are on foot slopes downslope and formed in local colluvium.
Clearfield, and Nira, soils are nearby at about the same elevations and have a
grayish B horizon.
Drainage and Permeability: Moderately well drained. Surface runoff is medium
to rapid (Soil Survey Staff, 1951). Permeability (saturated hydraulic
conductivity) is in the lower half of moderately high in the upper part of the
subsoil and in the upper half of moderately high in the lower part and in the
substratum.
Use and Vegetation: Commonly used for growing cultivated crops. Corn (Zea
mays L.), soybeans (Glycine max (L.) Merr), small grains, and hay are grown.
Native vegetation was tall prairie grasses.
Distribution and Extent: Southwestern Iowa, northwestern Missouri,
northeastern Kansas, and southeastern Nebraska. The soils are extensive.
Series Established: Lancaster County, Nebraska, 1944.
Remarks: Diagnostic horizons and features recognized in this pedon are:
mollic epipedon “the zone from the surface to a depth of 43 cm (Ap, A1, and A2
horizons); argillic horizon” the zone from 43 cm to a depth of 97 cm (Bt1, Bt2,
and Bt3 horizons); udic moisture regime.
Bakeoven Official Soil Series Description
The Bakeoven series consists of very shallow, well drained soils that formed
in mixed alluvium, loess, and residuum weathered from basalt. Bakeoven soils are
on uplands and have slopes of 0 to 90 percent. The mean annual precipitation is
about 330 mm and the mean annual temperature is about 9 °C.
Taxonomic Class: Loamy-skeletal, mixed, mesic Lithic Haploxerolls
Representative Pedon: Bakeoven very cobbly loam-rangeland. Colors are for dry
soil unless otherwise noted.
A—0 to 5 cm; brown (7.5YR 5/3) very cobbly loam, dark brown (7.5YR 3/2)
moist; weak thin platy and weak fine granular structure; slightly hard, friable,
slightly sticky and slightly plastic; common very fine roots; many very fine
irregular pores; about 40 percent by volume of rock fragments; slightly acid (pH
6.5); abrupt smooth boundary. (0 to 10 cm thick)
Bw1—5 to 10 cm; brown (7.5YR 5/3) very gravelly heavy loam, dark brown (7.5YR
3/3) moist; weak thin platy and weak fine and medium granular structure;
slightly hard, friable, sticky and plastic; common very fine roots; common very
fine irregular pores; about 60 percent by volume of rock fragments; neutral (pH
6.8); abrupt smooth boundary. (5 to 15 cm thick)
Bw2—10 to 18 cm; brown (10YR 5/3) very gravelly clay loam, dark brown (10YR
3/3) moist; moderate fine subangular blocky structure; hard, friable, sticky and
plastic; common very fine roots; common very fine tubular pores; about 60
percent by volume of rock fragments; neutral (pH 6.9); abrupt wavy boundary. (2
to 10 cm thick)
2R—18 cm; basalt.
Type Location: Wasco County, Oregon; 360 m south and 30 m east of center of
sec. 7; NW1/4, SE1/4 sec. 7. T. 8 S., R. 15 E.
Range in Characteristics: The soil is dry throughout above the lithic contact
for more than half the time (cumulative) that the soil temperature is above 5
°C. The mean annual soil temperature ranges from 8 to 12 °C. Thickness of solum
and depth to bedrock range from about 10 to 25 cm. Rock fragments commonly range
from 50 to 90 percent, but the upper 5 to 10 cm of the deeper sola have as
little as 35 percent. Organic matter ranges from 1 to 2 percent. The deeper part
of some sola have coatings of carbonates on the underside of rock fragments and
these coatings extend in cracks into the underlying rock. The sola have 10YR,
7.5YR, or 5YR hue.
The A horizon has value of 4 or 5 dry, 2 or 3 moist and chroma of 2 or 3
moist and 2 through 4 dry. It is slightly acid to mildly alkaline.
The B horizon has the same color value as that of the A horizon and chroma is
2 or 3 in the upper part and 3 or 4 below depths of 15 or 18 cm in sola thicker
than 18 cm. It is loam, clay loam or silt loam and averages more than 18 percent
clay and has more than 35 percent rock fragments. This horizon has moderate fine
subangular blocky through weak medium subangular blocky structure. It is
slightly acid to mildly alkaline.
Clay films are present on some rock fragments in deeper sola or in the
fractures in the underlying bedrock.
Competing Series: These are the Aldax, Bodell, Couleedam, Johntom,
Lickskillet, Limekiln, Plaskett, and Venator series. All of these soils are
deeper than 25 cm to bedrock. Aldax and Plaskett soils have less than 18 percent
clay in the particle-size control section. Limekiln soils have a calcic horizon.
Plaskett soils have mean annual soil temperature of 13 to 15 °C.
Geographic Setting: The Bakeoven soils are on ridge tops, hillslopes and
benches at elevations of 180 to 1600 meters. Slopes of 2 to 20 percent are most
common and the full range is from about 0 to 90 percent. The soils formed in
loess and residuum weathered from basalt. The climate is semiarid. The mean
annual precipitation ranges from 25 to 40 cm, the mean annual temperature is
from 7 to 11 °C, the mean winter temperature is from 7 to 11 °C, and the mean
summer temperature is from 17 to 19 °C. The frost-free period is 100 to 165
days.
Geographically Associated Soils: These are the competing Lickskillet soils
and the Anderly, Agency, Cantala, Condon, Gem, Maupin, Morrow, Reywat,
Ritzville, Ruckles, Starbuck, Walla Walla, Wapinitia, Watama and Wrentham soils.
Agency soils are moderately deep to bedrock and have less than 35 percent rock
fragments. Anderly and Condon soils are moderately deep and formed in loess over
bedrock and in many places are “biscuits” associated with Bakeoven soils.
Cantala soils are fine-silty and deeper than 1 m to bedrock. Gem and Morrow soil
have an argillic horizon and are moderately deep to bedrock. Maupin soils have a
duripan and are fine-loamy. Reywat soils are shallow and have a skeletal
argillic horizon. Ritzville and Walla Walla soils are deep or very deep, formed
in loess, and are free of rock fragments. Ruckles soils have a very stony
argillic horizon. Starbuck soils are on steep south-facing slopes, lack a mollic
epipedon, formed mostly in loess, and contain less than 35 percent rock
fragments. Wapinitia soils are deep and have an argillic horizon. Watama soils
are moderately deep and are fine-loamy. Wrentham soils are on steep north-facing
slopes and are deeper than 50 cm to bedrock.
Drainage and Permeability: Well drained; medium runoff (Soil Survey Staff,
1951); moderately slow permeability and in the moderately high saturated
hydraulic conductivity class. In a few places, the soil is ponded for short
periods.
Use and Vegetation: Most of the soil is used for range. Native vegetation is
bunchgrasses, forbs, and shrubs.
Distribution and Extent: North-central Oregon, eastern Washington, and
southwestern Idaho. This series is extensive.
Series Established: Sherman County, Oregon; 1962.
Condon Official Soil Series Description
The Condon series consists of moderately deep, well drained soils that formed
in loess overlying basalt. Condon soils are on uplands and have slopes of 0 to
40 percent. Mean annual precipitation is about 300 mm and the mean annual
temperature is about 9 °C.
Taxonomic Class: Fine-silty, mixed, mesic Typic Haploxerolls
Representative Pedon: Condon silt loam-cultivated. Colors are for dry soil
unless otherwise noted.
Ap—0 to 18 cm; grayish brown (10YR 5/2) silt loam, very dark brown (10YR 2/2)
moist; weak medium platy and weak medium granular structure; slightly hard,
friable, slightly sticky and slightly plastic; many very fine roots; common fine
irregular pores; neutral (pH 6.6); abrupt smooth boundary. (15 to 25 cm thick)
Bw1—18 to 36 cm; grayish brown (10YR 5/2) silt loam, very dark grayish brown
(10YR 3/2) moist; weak medium to coarse prismatic and weak medium subangular
blocky structure; slightly hard, friable, slightly sticky and slightly plastic;
many very fine roots; common very fine tubular pores; neutral (pH 6.7); clear
smooth boundary. (10 to 30 cm thick)
Bw2—36 to 50 cm; brown (10YR 5/3) silt loam, dark brown (10YR 3/3) moist;
weak medium to coarse prismatic and weak medium subangular blocky structure;
slightly hard, friable, slightly sticky and slightly plastic; many very fine
roots; common very fine tubular pores; neutral (pH 6.8); clear wavy boundary.
(10 to 30 cm thick)
BC—50 to 70 cm; pale brown (10YR 6/3) silt loam, dark brown (10YR 4/3) moist;
weak coarse prismatic structure; slightly hard, friable, slightly sticky and
slightly plastic; many very fine roots; common very fine tubular pores; neutral
(pH 7.0); abrupt wavy boundary. (0 to 50 cm thick)
2R—70 cm; basalt.
Type Location: Gilliam County, Oregon; 1.3 km west of Condon city limits; 53
m west of fence, 45 m north of Condon-Moro road in the SE1/4, SW1/4, NW1/4 sec.
9. T. 4 S., R. 21 E.
Range in Characteristics: The soils are usually moist but are dry for 80 to
90 consecutive days between depths of 10 and 30 cm following the summer
solstice. The mean annual soil temperature ranges from 8 to 12 íC. Thickness of
the solum and depth to bedrock range from 50 to 100 cm. Organic matter decreases
to less than 1 percent at depths of less than 50 cm and commonly between 25 and
38 cm.
The A horizon has value of 4 or 5 dry, 2 or 3 moist and chroma of 2 or 3
moist and dry. It is slightly acid or neutral.
The B horizon has value of 3 or 4 moist, 5 or 6 dry, but 3 moist and 5 dry
above 25 cm and chroma of 2 thru 4 moist and dry. It is silt loam and averages
18 to 27 percent clay and less than 15 percent coarser than very fine sand. This
horizon has weak to moderate structure. It is slightly acid through slightly
alkaline.
Competing Series: These are the Cantala and Couse series. Cantala and Couse
soils are deeper than 100 cm to bedrock.
Geographic Setting: Condon soils are on uplands at elevations of 330 to 1200
meters. Slopes are 0 to 40 percent. These soils formed in a loess mantle with an
appreciable component of volcanic ash overlying basalt. Summers are warm and dry
and winters are cool and moist. Mean summer temperature is 16 to 18 °C, and mean
winter temperature is 0 to 1 °C. Mean annual temperature is 7 to 9 °C.
Precipitation ranges from 250 to 380 mm. The frost-free period is 100 to 165
days.
Geographically Associated Soils: These are the Bakeoven, Lickskillet, Valby ,
and Wrentham soils and the competing Cantala soils. All of these except Valby
and Cantala soils contain more than 35 percent rock fragments. Also, Bakeoven
and Lickskillet soils are less than 50 cm deep to bedrock. Valby soils are
calcareous at depths of 38 to 76 cm.
Drainage and Permeability: Well drained; slow to rapid runoff; moderate
permeability.
Use and Vegetation: Principal use is for growing grain crops. Other uses are
production of hay, pasture, and native range. Native plants are bluebunch
wheatgrass (Agropyron spicatum (Scrib and J.G. Smith) A. Heller), Idaho fescue (Festuca
idahonsis Elmer), Sandberg bluegrass (Poa secunda J. Presl.), and forbs such as
yarrow (Achillea L.), phlox (Phlox L.), and buckwheat (Eriogonum Michx.).
Distribution and Extent: North-central Oregon and south-central Washington.
The series is extensive.
Series Established: Rock Creek Project, Gilliam County, Oregon, 1939.
Additional Data: Characterization data on 3 profiles (S57-OR-065-19,
S89OR-065-001, S89OR-065-002).
Series Revision Date-1/90
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