LOCATION VASHTI TXEstablished Series
TAXONOMIC CLASS: Fine-loamy, siliceous, superactive, thermic Aquic Haplustalfs
TYPICAL PEDON: Vashti loamy fine sand--wooded pasture.
(Colors are for dry soil unless otherwise stated.)
A1--0 to 3 inches; grayish brown (10YR 5/2) loamy fine sand,
very dark grayish brown (10YR 3/2) moist; weak fine granular
structure; soft, very friable; many fine roots; slightly acid;
clear smooth boundary. (2 to 6 inches thick)
A2--3 to 14 inches; light brown (7.5YR 6/4) loamy fine sand,
brown (7.5YR 5/4) moist; single grained; soft, very friable; few
fine roots; slightly acid; abrupt smooth boundary. (6 to 16
inches thick)
B21t--14 to 26 inches; yellowish brown (10YR 5/6) sandy clay
loam, dark yellowish brown (10YR 4/6) moist, with many medium
distinct red (2.5YR 4/8) mottles and a few fine distinct gray
mottles; moderate fine subangular blocky structure; very hard,
firm; few fine roots; many fine pores; continuous clay films on
faces of peds; medium acid; gradual smooth boundary. (4 to 16
inches thick)
B22t--26 to 36 inches; yellow (10YR 7/6) sandy clay loam,
yellowish brown (10YR 5/6) moist, with few faint reddish yellow
mottles and common medium prominent light gray (10YR 7/1) mottles;
weak fine subangular blocky structure; hard, firm; patchy clay
films on faces of peds; medium acid; abrupt smooth boundary. (8
to 18 inches thick)
R--36 to 42 inches; strongly cemented brownish sandstone
bedrock.
TYPE LOCATION: Erath County, Texas; approximately 18 miles
northwest of Stephenville, Texas; from the county road
intersection at the Russell Chapel Cemetery, 0.55 mile south on
county road and 120 feet west of road in wooded pasture.
RANGE IN CHARACTERISTICS: Solum thickness and depth to strongly
cemented or indurated sandstone bedrock ranges from 20 to 40
inches. Coarse fragments of sandstone and chert mainly less than
10 inches across ranges from 0 to 15 percent by volume in the
solum. Sandstone and ironstone fragments about 10 to 24 inches
across cover 0 to 15 percent of the soil surface. The fragments
are usually partially imbedded in the surface layer.
The A horizon has hue of 7.5YR and 10YR, value of 3 through 6, and
chroma of 2 through 4. The A2 horizon is typically 1 or 2 units
of value greater than the A1 horizon. Texture is loamy fine sand,
fine sandy loam, or stony loamy fine sand. Reaction is slightly
acid or neutral.
The Bt horizon has hue of 7.5YR, 10YR, and 2.5Y, value of 5
through 7, and chroma of 2 through 8. Mottles in shades of red,
brown, or yellow and mottles with chroma of 2 or less range from
few to many. Some pedons have a mottled matrix. Texture is sandy
clay loam or clay loam with clay content of 20 to 35 percent. The
reaction ranges from medium acid through neutral.
Competing Series: There are no competing series in the same
family. Other competing soils in similar families are the Cobb,
Hye, Shavash, and Stephenville series. Cobb, Hye, and
Stephenville soils have argillic horizons with hues redder than
7.5YR. Shavash soils have sola less than 20 inches thick and lack
mottles with chroma of 2 or less.
GEOGRAPHIC SETTING: Vashti soils are gently sloping with plane or
slightly concave surfaces. They are mainly on stream divides with
slopes of 1 to 5 percent. The soils formed in residuum from
sandstone of Pennsylvanian age. The climate is dry subhumid. The
mean annual temperature ranges from 64 degrees to 67 degrees F.;
annual precipitation is 26 to 32 inches; and Thornthwaite P-E
indices are 38 to 50.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the competing
Shavash series and the Bonti, Chaney, Exray, Shatruce, and Truce
series. Shavash soils are also on stream divides. Bonti and
Chaney soils have fine textured argillic horizons. Bonti soils
are below along hillsides. Chaney soils are below on stream
divides. Exray soils have sola less than 20 inches thick and are
below along hillsides. Shatruce ad Truce soils are formed in
shaly materials and have fine textured argillic horizons.
Shatruce soils are on bouldery escarpments. Truce soils are below
along hillsides or on lower stream divides.
Drainage and Permeability: Moderately well drained; slow to
medium runoff; moderate permeability. Water is perched above the
bedrock for short periods following heavy rainfall. The periods
are less than a month in duration.
USE AND VEGETATION: Vashti soils are used mainly for rangeland
but significant areas are in lovegrass and bermudagrass pastures.
A few areas are cultivated to peanuts or sorghums. The climax
plant community is mid and tall grasses in an open savannah of
postoak and blackjack oak. Primary grasses and forbs include
bluestems, indiangrass, sand lovegrass, sand dropseed, tall
dropseed, western ragweed, dalea species and trailing wildbean
with greenbrier and bumelia. Low producing grasses and forbs as
well as mesquite, cedar, and elm trees have invaded.
DISTRIBUTION AND EXTENT: Mainly in the Texas North Central
Prairie Land Resource Area; the series is of moderate extent.
SERIES ESTABLISHED: Gillespie County, Texas; 1970.