LOCATION RABUN GA+NC SC TN VAEstablished Series
TAXONOMIC CLASS: Clayey, kaolinitic, mesic Typic Rhodudults
TYPICAL PEDON: Rabun loam, on a concave 18 percent slope, in
forest.
(Colors are for moist soil unless otherwise stated.)
0i--1 to 0 inch; partially decomposed leaves and branches;
few fine roots; medium acid.
A1--0 to 2 inches; dark reddish brown (5YR 3/3) loam; weak
fine granular structure; very friable; many fine and medium roots; few pebbles; medium acid; clear smooth boundary. (2 to 6 inches thick)
A2--2 to 9 inches; dark reddish brown (5YR 3/4) loam;
moderate medium granular structure; very friable; many fine and medium roots; few pebbles; medium acid; clear smooth boundary. (0
to 9 inches thick)
Bt1--9 to 14 inches; dark red (2.5YR 3/6) clay; weak fine subangular blocky structure; friable; common fine and medium
roots; medium acid; clear smooth boundary. (0 to 9 inches thick)
Bt2--14 to 37 inches; dark red (2.5YR 3/6) clay; moderate
medium subangular blocky structure; firm; common fine and medium roots; thin continuous clay films on faces of peds; common strong brown (7.5YR 5/6) medium and coarse fragments of saprolite; medium acid; gradual wavy boundary. (18 to 36 inches thick)
BC--37 to 48 inches; dark red (2.5YR 3/6) clay; weak medium subangular blocky structure; friable; few fine and medium roots; common strong brown (7.5YR 5/6) medium and coarse fragments of saprolite; medium acid; gradual wavy boundary. (5 to 15 inches thick)
C--48 to 62 inches; strong brown (7.5YR 5/6) and yellowish
red (5YR 5/6) loose soft rock fragments about 2 to 10 mm in size; dark red (2.5YR 3/6), red (2.5YR 4/6), and strong brown (7.5YR
5/6) loam soil material in pockets and between rock fragments; massive; common angular hard pebbles and cobbles; medium acid.
TYPE LOCATION: Towns County, Georgia; 7.9 miles west of Hiawassee
on U. S. 76, 1.2 miles east on dirt road 10 feet east of road
bank.
RANGE IN CHARACTERISTICS: Solum thickness ranges from 30 to 60 inches. Depth to hard rock ranges from 5 to 10 feet or more. Reaction ranges from strongly acid to slightly acid.
The A horizon has hues of 10R to 5YR, value of 3 and chroma of 2 through 6. Texture of the fine earth fraction is loam, clay loam,
or silt loam. Eroded areas range to clay texture. Pebbles,
cobbles, and stones range from 2 to 35 percent by volume.
The Bt1 horizon has hues of 10R to 2.5YR, value of 3 and chroma of
2 through 6. It is clay loam, silty clay loam, silty clay, or
clay. Pebbles and cobbles range from 0 to 15 percent by volume.
The Bt2 horizon has hues of 10R to 2.5YR, values of 3 or 4 and
chroma of 2 through 8. It is clay loam, silty clay loam, silty
clay, or clay. Pebbles and cobbles range from 0 to 15 percent by volume. Structure ranges from moderate to strong angular to subangular blocky.
The BC horizon has hue of 10R to 2.5YR, values of 3 or 4 and
chroma of 2 through 8. Medium to coarse red and brown mottles
range from none to common. Texture is loam, clay loam, silty clay loam, stony clay loam, clay, or cobbly clay loam. Pebbles,
cobbles, and stones range from 10 to 25 percent, many of which are fragments of saprolite.
The C horizon has hues of 10R to 2.5YR, values of 3 or 4, and
chroma of 6 through8. This fine earth fraction of clay loam and
loam fills cracks, pockets, and space between rock fragments. The soil comprises 3 to 8 percent of the horizon by volume. Pebbles, cobbles, and greenstone make up the remainder of the horizon. 2
to 20 percent of these fragments are hard, others are weathered
and soft.
COMPETING SERIES: These are the
Coronaca,
Cumberland,
Davidson,
Dyke,
Gwinnett,
Hanceville,
Hiwassee,
Musella,
Rapidan, and
Tellico series of closely related families. Coronaca, Cumberland, and Davidson soils have solum thickness of more than 60 inches; in addition, Coronaca and Cumberland soils have base saturation of more than 35 percent at a depth of 50 inches below the top of the argillic horizon. Dyke soils have mixed mineralogy and a regolith of local colluvial material in concave and toeslope landscapes. Gwinnett, Hanceville, Hiwassee, Musella, and Tellico soils have mean annual soil temperatures higher than 59 degrees F. In addition, Musella soils have a solum thickness less than 20 inches. Rapidan soils
have more than 35 percent silt in the control section.
GEOGRAPHIC SETTING: Rabun soils are on narrow sloping ridges and long steep and very steep mountain slopes. Slopes range from 2 to
50 percent but are dominately 25 to 45 percent. The soil formed
in material weathered from dark colored rocks high in
ferromagnesium minerals. The average annual air temperature near
the type location is about 57 degrees F. and the average annual precipitation is about 71 inches.
GEOGRAPHICALLY ASSOCIATED SOILS: These include the Dyke
series and the
Ashe,
Chester,
Clifton,
Hayesville,
Myersville,
Porters, and
Watauga series. Ashe soils lack argillic horizons,
and have a coarse loamy control section. Chester, Clifton, Hayesville, Myersville, Porters, and Watauga soils have color
values of more than 4 in argillic horizons. The mean annual temperature ranges from about 50 to 58 degrees F. and the mean annual precipitation ranges from about 55 to 75 inches.
DRAINAGE AND PERMEABILITY: Well drained; moderate to rapid
runoff; moderate permeability.
USE AND VEGETATION: Most of the sloping and much of the
moderately steep soils have been cleared and used for corn, hay,
and pasture. Concave forested areas are mostly in yellow-poplar ridges and long slopes are mostly in upland oaks, eastern white
pine, pitch pine, shortleaf pine, pignut hickory, and mockernut hickory.
DISTRIBUTION AND EXTENT: Appalachian Mountains of Georgia, North Carolina, South Carolina, Tennessee, and Virginia. The series is
of moderate extent.
MLRA OFFICE RESPONSIBLE: Lexington, Kentucky
SERIES ESTABLISHED: Macon County, North Carolina; 1929.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Argillic horizon - the zone from approximately 9 to 48 inches
(Bt1, Bt2, BC horizond)
Rhodic feature - the zone in the argillic with color values of 3 from approximately 9 to 48 inches (Bti, Bt2, BC horizons)