LOCATION RAHAL TXEstablished Series
TAXONOMIC CLASS: Clayey, mixed, active, hyperthermic Arenic Albaqualfs
TYPICAL PEDON: Rahol fine sand--rangeland. (Colors are for dry soil unless otherwise stated.)
A1--0 to 10 inches; light brownish gray (10YR 6/2) fine sand, grayish brown (10YR 5/2) moist; single grained; loose; few coarse roots and common fine roots; neutral; clear smooth boundary. (5 to 16 inches thick)
A2g--10 to 35 inches; white (10YR 8/2) fine sand, light gray (10YR 7/2) moist; single grained; loose; few coarse roots; neutral; abrupt smooth boundary. (12 to 35 inches thick)
B21tg--35 to 48 inches; light gray (10YR 7/2) sandy clay, light brownish gray (10YR 6/2) moist; common, coarse, distinct yellowish brown (10YR 5/6) mottles; moderate coarse blocky structure; very hard, firm, sticky; few fine roots mostly between peds; few fine pores; many clay films; clean sand grains on vertical surfaces of peds; mildly alkaline; gradual smooth boundary. (10 to 30 inches thick)
B22tg--48 to 62 inches; white (10YR 8/2) sandy clay, light gray (10YR 7/2) moist, few coarse prominent red (2.5YR 4/8) and fine distinct brownish yellow (10YR 6/6) mottles; moderate coarse blocky structure; very hard, firm, sticky; few fine roots; few fine pores; many clay films; clean sand grains on vertical surfaces of peds; mildly alkaline; gradual smooth boundary. (0 to 16 inches thick)
B3g--62 to 80 inches; white (10YR 8/1) sandy clay loam, light gray (10YR 7/1) moist, common medium faint light yellowish brown (2.5Y 6/4) and prominent dark red (2.5YR 3/6) mottles; weak coarse blocky structure; hard, firm, slightly sticky; few fine roots; few fine pores; mildly alkaline; gradual smooth boundary. (8 to 19 inches thick)
Cg--80 to 96 inches; white (10YR 8/1) fine sandy loam, light gray (10YR 7/1) moist; common medium prominent red (2.5YR 4/6) and common fine distinct light olive brown (2.5Y 5/6) mottles; massive; slightly hard, friable; moderately alkaline.
TYPE LOCATION: Calhoun County, Texas; about 10 miles south of Port Lavaca; or 8.2 miles south of intersection of Texas Highway 238 and Farm Road 1289. Site is 30 feet east of Farm Road 1289 about 0.7 mile south of Coloma Creek.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 50 to 90 inches.
The A horizon is fine sand or loamy fine sand. It is medium acid through neutral. The A horizon is 20 to 40 inches thick. The A1 horizon is light gray (10YR 6/1, 7/2), gray (10YR 5/1), grayish brown (10YR 5/2), or light brownish gray (10YR 6/2). The+AA2g horizon is light gray (10YR 7/2) or white (10YR 8/2).
The B2tg horizons are light brownish gray (10YR 6/2; 2.5Y 6/2) or light gray (10YR 6/1, 7/1, 7/2; 2.5Y 7/2) and have mottles of yellows, reds, and browns. They are clay, sandy clay, or clay loam. Clay content of the upper 20 inches of the Btg horizon ranges from 35 to 50 percent. It is neutral or mildly alkaline.
The B3g horizon is white (10YR 8/1, 8/2; 2.5Y 8/2; 5Y 8/1, 8/2), light gray (2.5Y 7/2; 5Y 7/1, 7/2), or light brownish gray (2.5Y 6/2; 10YR 6/2). It has mottles of yellows, browns, and reds. The B3g is sandy clay, clay loam, or sandy clay loam. It is mildly or moderately alkaline. The Cg horizon is fine sandy loam, sandy clay loam, clay loam, or sandy clay. It is gray to white. In some pedons the Cg horizon has concretions or masses of calcium carbonate.
COMPETING SERIES: These include the Crowley, Fordtran, Galveston, Mustang, Panasoffkee, Portalto, and Roemer series. Crowley soils have silt loam or fine sandy loam A horizons. Fordtran soils have slightly acid to strongly acid B2tg horizons. Galveston and Mustang soils lack an argillic horizon. Panasoffkee soils lack an abrupt texture change between the A and Bt horizons. Portalto soils lack an argillic horizon within 40 inches. Roemer soils have less than 35 percent clay in the Bt horizons.
GEOGRAPHIC SETTING: Rahal soils occupy gently undulating uplands near the bays. Slopes range from 0 to 3 percent. The soils formed in clayey and loamy sediments. The climate is humid subtropical. Average annual precipitation ranges from 30 to 38 inches. The Thornthwaite annual P-E index is 44 to 52. Average annual temperature ranges from 70 degrees to 73 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Portalto and Roemer series, as well as the Livia and Motagorda series. Livia and Matagorda soils lack sandy surface horizons.
DRAINAGE AND PERMEABILITY: Somewhat poorly drained; very slow runoff; very slow permeability. Permeability is rapid in the surface soil and very slow in the subsoil. A water table is perched above the Btg horizon during winter and spring months.
USE AND VEGETATION: Used for range. Native vegetation consists mainly of running live oak and coarse bunch grasses, mainly andropogons, low panicums, and purpletop.
DISTRIBUTION AND EXTENT: Near the bays along the Texas gulf coast. They are of moderate extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Calhoun County, Texas; 1972.
REMARKS: Rahal soils would have been formerly classified in the Regosols great soil group.