LOCATION RUPLE LAEstablished Series
TAXONOMIC CLASS: Fine, parasesquic, thermic Typic Rhodudults
TYPICAL PEDON: Ruple gravelly loam--on a 3 percent convex east-facing slope in mixed pine-hardwood forest.
(Colors are for moist soil unless otherwise stated)
Ap--0 to 6 inches: dark reddish brown (2.5YR 3/4) gravelly loam; moderate fine granular structure; friable; many fine and common medium roots: about 20 percent by volume small, angular and flattened fragments of ironstone that have minimum dimensions from 1/8-inch to 3 inches about 5 percent of the fragments have one dimension larger than 3/4 inches; slightly acid; abrupt smooth boundary. (3 to 8 inches thick)
Bt1--6 to 14 inches; dark red (2.5YR 3/6) gravelly clay: moderate medium and fine subangular blocky structure; friable; many fine and common medium roots: few fine pores: thick patchy clay films on all faces of peds; about 20 percent by volume flattened and angular fragments of ironstone that have minimum dimensions of from 1/8-inch to 3 inches; about 5 percent of the flattened fragments have at least one dimension larger than 3/4-inch; smoothly acid; clear wavy boundary. 3 to 12 inches thick)
Bt2--14 to 23 inches: dark red (2.5YR 3/6) gravelly clay; moderate medium and fine subangular blocky structure; friable; common fine and few medium roots: few fine pores: thick patchy clay films on all faces of peds; about 20 percent by volume flattened and angular fragments of ironstone that have minimum dimensions of from 1/8-inch to 3 inches; about 25 percent of the fragments have one dimension larger than 3/4 inch; slightly acid; clear wavy boundary. (4 to 12 inches thick)
Bt3--23 to 28 inches: dark red (2.5YR 3/6) clay: weak medium and fine subangular blocky structure; friable; common fine roots; few fine pores; thick patchy clay films mostly on vertical faces of peds; about 5 percent by volume flattened and angular fragments of ironstone that have minimum dimensions of from 1/10 inch to 3 inches; slightly acid; clear wavy boundary. (4 to 20 inches thick)
Bsm/Btl--28 to 42 inches: alternating layers of fractured ironstone (Bsm) about 0.25 to 4 inches thick and dark red (2.5YR 3/6) clay (Bt); petroferric (ironstone) layers are fractured into flattened fragments that range in length from 1 inch to 8 inches; the average lateral distance between fractures is about 4 to 6 inches; the clay part (Bt) has moderate coarse and medium subangular blocky structure; friable; few fine and medium roots in clay flows and between cracks in the ironstone layers; thick patchy clay films on vertical faces of the clayey peds: few pockets and layers of partally weathered yellowish red (5YR 5/6) loamy and sandy material that are enclosed within or sandwiched between rinds of ironstone: few fine pockets and streaks of whitish kaolin; moderately acid: clear wavy boundary (8 to 20 inches thick)
Bsm/Bt2--42 to 63 inches: alternating layers of fractured ironstone (Bsm) about 0.25 inch to 8 inches thick and dark red (2.5YR 3/6) clay (Bt): petroferric (ironstone) layers are fractured into flattened fragments that range in length from 1 to 8 inches; average lateral distance between fractures is about 4 to 6 inches; the clay part (Bt) has weak coarse and medium subangular blocky structure; friable; thick patchy clay films on vertical faces of the clayey peds; common pockets and layers of partially weathered yellowish red (5YR 5/6) loamy and sandy material that are enclosed within or sandwiched between rinds of ironstone few fine pockets and streaks of whitish kaolin; moderately acid.
TYPE LOCATION: Webster Parish, Louisiana; 4 miles south of Leton; 450 feet east of Highway 159, SE1/4SW1/4 sec. 14, T. 21 N., R. 9 W.
RANGE IN CHARACTERISTICS: Solum thickness exceeds 60 inches. Average clay content of the textural control section ranges from 45 to 70 percent. Clay content decreases with depth in the profile. Coarse fragments (ironstone) make up from 15 to 35 percent of the volume of the surface layer and the text textural control section. The base saturation by sum is typically greater than 45 percent throughout the textural control section. Base saturation decreases with depth. The depth to the first nearly continuous layer of ironstone ranges from about 20 to 40 inches.
The A horizon has hue of 10R or 2.5YR, value of 2 or 3, and chroma of 2 to 6. It is gravelly loamy fine sand, gravelly fine sandy loam, gravelly loam, or gravelly clay loam. Reaction ranges from moderately acid to neutral.
The Bt horizon above the layers of ironstone, has hue of 10R or 2.5YR, value of 3, and chroma of 3 to 6. Texture typically is gravelly clay loam, gravelly sandy clay, or gravelly clay. Content of clay ranges from 40 to 80 percent and averages about 45 to 70 percent. Angular and flattened fragments of ironstone range from 1/8-inch to 2 inches in thickness and from 1/2-inch to 8 inches in length. Fragments of ironstone can make up from 5 to 35 percent of the volume of any subhorizon, but the average is greater than 15 percent. Reaction ranges from strongly acid to slightly acid.
The Bsm/Bt horizon consists of alternating layers of clayey material and fractured ironstone layers. The clayey part has the same range in colors as the upper part of the Bt horizon. It is clay, sandy clay or clay loam. The ironstone layers are fractured and range in thickness from 1/4-inch to 12 inches. The lateral distance between fractures ranges from 2 to 20 inches and averages 4 to 8 inches. Typically the layers are continuous for many feet. In some pedons, the layers are intermittent and extend only a few feet horizontally. In other pedons, the layers are parts of large spheroidal configurations that are separated from one another by vertical flows of clay, sandy clay or clay loam. The partially weathered loamy and sandy material, that is in pocket and layers, has hue of 5YR, 7.5YR, or 10YR, value of 4 or 5, and chroma of 4 to 8. It is fine sand, loamy fine sand, sandy loam, fine sandy loam, sandy clay loam, or clay loam that contains large amounts of siderite. Pockets and streaks of whitish or grayish kaolin range from fine to medium and from few to common. Reaction ranges from very strongly acid to slightly acid.
COMPETING SERIES: The Tellico series is in the same family. Similar series include Alcoa, Anniston, Cuthbert, Davidson, Decatur, Greenville, Gwinnett, Hiwasse, Kirvin, and Nacogdoches. The Alcoa soils formed in basic rock and have an argillic horizon that does not decrease in content of clay by more than 20 percent within 60 inches of the soil surface. The Anniston, Davidson. Decatur, Greenville, Gwinnett, Hiwasse, and Nacogdoches soils have kaolinitic mineralogy. The Cuthbert and Kirvin soils have mixed mineralogy and contain less ironstone than the Ruple species. The Tellico soils are underlain by sandstone.
GEOGRAPHIC SETTING: Ruple soils are on convex ridgetops and upper side slopes in the uplands of the Western Coastal Plains. Slopes range from 1 to 12 percent. The soils formed in iron-rich, clayey, marine sediments. The typical pedon is forming in sediments of the Cook Mountain Formation, Claiborne Group, Eocene Series. The mean annual temperature is 64 degrees F., and the mean annual precipitation is 51 inches.
GEOGRAPHlCALLY ASSOCIATED SOILS: These are the Bowie and Sacul soils and the competing Kirvin soils. The Bowie soils are on ridgetops at similar elevations and are fine-loamy. The Kirvin soils are on similar landscapes. The Sacul soils are on side slopes at lower elevations, and they have mixed minerology and contain less ironstone than the Rupple soils.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is medium to rapid Permeability is moderately slow.
USE AND VEGETATION: Most areas of Ruple soils are in woodland or pastureland. Small areas are cultivated. Loblolly pine is the main tree species. Coastal bermudagrass and bahiagrass are the main pasture crops. Native vegetation consisted of a mixed oak and pine forest.
DISTRIBUTION AND EXTENT: Ruple soils are mainly in north-centra1 Louisiana The area is of small extent, about 8,600 acres.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Temple, Texas
SERIES ESTABLISHED: Claiborne Parish, Louisiana, 1986.
REMARKS: The ironston layers qualify for a petroferric contact. If a petrofettic subgroup existed in this order, this series would be a candidate for such a classification.
ADDITIONAL DATA: Laboratory data on the typitying pedon by NSSL. Sample No. S82LAll9-1(1-6)