LOCATION DOUDLE TXEstablished Series
TAXONOMIC CLASS: Coarse-loamy, carbonatic, thermic Typic Haplustepts
TYPICAL PEDON: Doudle cobbly loam - rangeland.
(Colors are for dry soil unless otherwise stated.)
A--0 to 6 inches, brown (7.5YR 5/2) cobbly loam, dark
brown (7.5YR 3/2) moist; moderate very fine subangular
blocky structure; hard, friable; common fine roots; common
fine pores; few fragments of caliche ranging up to about 2
inches in diameter; about 20 percent by volume of caliche
and calcareous cobbles of sandstone; strong effervescence,
moderately alkaline; clear smooth boundary. (4 to 12 inches
thick)
Bk1--6 to 13 inches, light brown (7.5YR 6/4) loam, brown
(7.5YR 5/4) moist; moderate very fine subangular blocky
structure; hard, friable; common fine roots; common fine
pores; common medium weakly cemented bodies of calcium
carbonate; common medium concretions of calcium carbonate;
common fragments of caliche and calcareous sandstone, which
range from 3 inches to about 12 inches across and 2 inches
thick; violent effervescence, moderately alkaline; clear
smooth boundary. (6 to 20 inches thick)
Bk2--13 to 36 inches, pink (5YR 7/4) silt loam, reddish
yellow (5YR 6/6) moist; weak very fine subangular blocky
structure; hard, friable; common fine roots and few coarse
roots; common fine pores; medium bodies of calcium carbonate
comprise about 15 percent of the horizon; few medium
concretions of calcium carbonate; few fine fragments of
caliche; violent effervescence, moderately alkaline; clear
smooth boundary. (10 to 26 inches thick)
Ck--36 to 48 inches, stratified reddish yellow and pink
weakly cemented fine grained calcareous sandstone and pink
(5YR 7/4) silt loam; massive; sandstone is hard when dry,
brittle and weakly cemented when moist; common medium soft
bodies of calcium carbonate; violent effervescence,
moderately alkaline; gradual smooth boundary. (10 to 30
inches thick)
C--48 to 60 inches, stratified light reddish brown (5YR
6/4) loam and clay loam, reddish brown (5YR 5/4) moist;
massive; slightly hard, friable; common lenses and pockets
of dusky red, weak red, pale red, and pinkish gray; few
strongly cemented fragments of calcareous sandstone;
estimated more than 40 percent calcium carbonate equivalent;
violent effervescence, moderately alkaline.
TYPE LOCATION: Brown County, Texas; from the intersection
of Farm Road 45 and Indian Creek Road in southern Brown
County, about 1 mile northeast and .5 mile southeast on a
county road; then 200 feet southwest of the road and just
south of a small caliche pit.
RANGE IN CHARACTERISTICS: The solum ranges from 22 to 40
inches thick to the paralithic contact with sandstone. Clay
content, within the 10- to 40-inch control section, ranges
from 8 to 18 percent. Calcium carbonate equivalent ranges
from 40 to 60 percent.
The A horizon is grayish brown to reddish brown in hue of
5YR to 10YR, value of 4 or 5 and chroma of 2 through 4.
Pedons with moist values and chromas less than 3.5 have A
horizons less than 7 inches thick. Texture is cobbly loam,
cobbly very fine sandy loam, or cobbly silt loam. Reaction
ranges from mildly alkaline to moderately alkaline.
The Bk horizons are brown to light reddish brown in hue of
5YR through 10YR, value 5 through 7 and chroma of 2 through
6. Texture is loam, silt loam, or very fine sandy loam.
The C horizons range from weakly to strongly cemented
calcareous pink sandstone interbedded with loam and clay
loam.
COMPETING SERIES: These are the
Brackett,
Hext,
Karnes,
Seawillow,
Shep, and
Weymouth series. Brackett soils have
sola less than 20 inches thick. Hext soils have mixed
mineralogy. Karnes soils lack a paralithic contact with
sandstone within 40 inches depth. Seawillow and Shep soils
have fine-loamy control sections and lack a paralithic
contact with sandstone within 40 inches depth. Weymouth
soils have fine-loamy control sections and mixed mineralogy.
GEOGRAPHIC SETTING: Doudle soils are on gently sloping to
strongly sloping low ridges and knolls of the uplands.
Slopes are dominantly less than 5 percent but range from 1
to 12 percent. The soils developed in weakly consolidated, calcareous, sandstones and loamy earths, locally called Pink Sandstone and Pink Caliche. The unique formation is thought
to be a basal member of Lower Cretaceous Age. At the type
location, the mean annual precipitation is about 27 inches,
mean annual temperature about 65 degrees F., and
Thornthwaite annual P-E index is about 40.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the
competing
Brackett series, and the
Bolar,
Menard,
Pedernales, and
Real series. Bolar soils have mollic
epipedons and fine-loamy control sections. Menard and
Pedernales soils have argillic horizons, and in addition,
Pedernales soils have more than 35 percent clay in the
control section. Real soils have mollic epipedons and have
sola less than 20 inches thick.
DRAINAGE AND PERMEABILITY: Well drained; medium runoff;
moderately rapid permeability.
USE AND VEGETATION: Mostly used for rangeland. A few areas
have been cultivated to small grain or grain sorghum, but
the fields are mostly now in grass. Native vegetation
consists mainly of little bluestem, sideoats grama, yucca,
and live oak trees.
DISTRIBUTION AND EXTENT: Mainly in Central Texas, and known
areas are confined mainly to Brown and Mills Counties. The
series is of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Brown County, Texas; 1975
REMARKS: The Doudle series would have been formerly placed
in the Regosol great soil group. The soils were previously
included in the Shep series. Diagnostic horizons and
features recognized in this pedon are : Ochric epipedon - 0
to 6 inches, Cambic horizon - 6 to 36 inches, 6 to 36
inches, Calcic horizon - 6 to 36 inches.