LOCATION NAVO TXEstablished Series
TAXONOMIC CLASS: Fine, smectitic, thermic Udertic Paleustalfs
TYPICAL PEDON: Navo clay loam--pasture. (Colors are for dry soil unless otherwise stated.)
Ap--0 to 5 inches; brown (7.5YR 5/4) clay loam, dark brown (7.5YR 3/2) moist; massive; very hard, very firm, sticky and plastic; few fine roots; few fine pores; few fine black concretions; slightly acid; clear smooth boundary. (5 to 9 inches thick)
B21t--5 to 10 inches; yellowish red (5YR 5/6) clay, yellowish red (5YR 4/6) moist; moderate coarse blocky structure; extremely hard, very firm, very sticky and plastic; common fine roots mainly on surface of peds; few fine pores; few thin patchy clay films; few fine black concretions; medium acid; gradual wavy boundary. (5 to 16 inches thick)
B22t--10 to 22 inches; mottled weak red (2. 5YR 4/2) and reddish brown (5YR 4/4) clay; moderate medium and coarse blocky structure; extremely hard, very firm, very sticky and plastic; common fine roots on surface of peds; thin distinct clay films on vertical faces of peds; few fine black concretions; medium acid; diffuse clear boundary. (7 to 24 inches thick)
B23t--22 to 48 inches; light brownish gray (2.5Y 6/2) clay, grayish brown (2.5Y 5/2) moist; common fine distinct reddish brown (5YR 4/4) mottles; moderate medium and coarse blocky structure; extremely hard, very firm, very sticky and plastic; few fine roots on surface of peds; thin, distinct clay films on faces of peds; few fine vertical streaks of darker material from above; few fine black concretions and few fine concretions of calcium carbonate; moderately alkaline; diffuse wavy boundary. (4 to 30 inches thick)
B24t--48 to 72 inches; light yellowish brown (10YR 6/4) clay, yellowish brown (10YR 5/4) moist; common fine distinct strong brown (7.5YR 5/6) and gray (N 5/ ) mottles; moderate medium and coarse blocky structure; extremely hard, very firm, very sticky and plastic; few fine roots on surface of peds; few thin patchy clay films on surface of peds; few fine pebbles of quartz; few fine black concretions and few fine concretions of calciumcarbonate; moderately alkaline; diffuse wavy boundary. (0 to 24 inches thick)
B3--72 to 95 inches; yellow (10YR 7/6) clay, few fine distinct gray (N 5/ ) mottles, brownish yellow (10YR 6/6) moist; moderate coarse blocky structure; extremely hard, very firm, very sticky and plastic; few fine roots; few thin patchy clay films; about 5 percent concretions and soft masses of calcium carbonate; strong effervescence; moderately alkaline.
TYPE LOCATION: Denton County, Texas. About 0.4 mile north of Flower Mound New Town City offices, on paved county road, and 200 feet east of right-of-way into pasture.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 60 to more than 80 inches. Depth to secondary carbonates ranges from 30 to about 80 inches. There are a few black concretions throughout most pedons.
The A horizon has hue of 7.5YR and 10YR, value of 4 or 5, and chroma of 2 through 4. It is clay loam or sandy clay loam. The reaction ranges from medium acid through neutral.
Texture of the argillic horizon is clay or clay loam with clay content of 35 to 55 percent. The B21t and B22t horizons are variable in color within a distance of a few feet and are mottled or have a matrix of reddish or brownish colors. They have hue of 5YR through 10YR, value of 4 through 6 and chroma of 2 through 8. Some mottles have hue of 2.5YR. The lower B2t horizons are in shades of brown, gray, or yellow and are typically mottled with these or reddish colors. The B21t and B22t horizons are medium acid through neutral. The lower B2t horizons are neutral through moderately alkaline. Some pedons are calcareous in the lower part.
Lower B3 and C horizons when encountered have brown, yellow or olive colors with or without grayish or reddish mottles. They are clay or clay with strata or pockets of shaly clay. Some pedons have shaly clay C horizons below a depth of 60 inches. The reaction ranges from neutral through moderately alkaline with few or common concretions and soft masses of calcium carbonate.
COMPETING SERIES: These include the Axtell, Crockett, Crosstell and Tabor series in the same family and the Bazette, Normangee, Payne, Ponder and Steedman series in similar families. Axtell, Crockett, Crosstell, and Tabor soils have an abrupt texture change between the A and B2t horizons. Bazette, Normangee and Steedman soils have sola less than 60 inches thick. The Payne series have COLE of less than .07. Ponder soils have a 20 percent decrease in clay content from the maximum within a depth of 60 inches.
GEOGRAPHIC SETTING: Navo soils are on high stream terraces. Slopes range from 0 to 8 percent but are mainly 1 to 3 percent. The soil formed in alkaline clayey sediments. The mean annual temperature ranges from 64 degrees to 68 degrees F. Average annual precipitation ranges from 30 to 42 inches. Thornthwaite P-E indices range from 52 to 64.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Axtell and Crockett soils and the Callisburg, Heiden, Justin, and Wilson soils. Callisburg and Justin soils lack vertic properties. Heiden soils are clayey throughout. Wilson soils have gray colors throughout. Axtell and Heiden soils are above on slopes or ridgetops. Crockett and Justin soils are on positions similar to Navo soils. Wilson soils are below in nearly level or slighlty depressed areas.
DRAINAGE AND PERMEABILITY: Moderately well drained; medium runoff; very slow permeability.
USE AND VEGETATION: Used for cropland, pasture, and rangeland. Crops are cotton, grain sorghum, and small grain. Pastures are common and coastal bermudagrass. Native vegetation is mainly bluestem, Texas wintergrass, meadow dropseed and threeawn. Scattered elm, mesquite, and post oak trees are present in some areas.
DISTRIBUTION AND EXTENT: Mainly in north central Texas, along the west part of Blackland Prairie and broad terraces and valley fill areas of the East Cross Timbers. The series is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Denton County, Texas; 1975
REMARKS: Navo soils would have formerly been classified in the Reddish Prairie great soil group and they have previously been included in the Normangee series.