LOCATION DURBIN FLEstablished Series
TAXONOMIC CLASS: Euic, hyperthermic Typic Sulfisaprists
TYPICAL PEDON: Durbin muck--tidal marsh (Colors are for moist soil).
Oa1--0 to 6 inches; very dark grayish brown (10YR 3/2) muck; 40 percent fiber, 16 percent rubbed; massive; slightly sticky; many fine and medium roots; 1.27 percent sulfur; 192.0 mmho/cm conductivity; extremely acid; gradual smooth boundary. (6 to 8 inches thick)
Oa2--6 to 25 inches; very dark gray (10YR 3/1) muck; 16 percent fiber, 4 percent rubbed; massive; slightly sticky; common fine and medium roots; 1.62 percent sulfur; 96.2 mmho/cm conductivity; very strongly acid; gradual wavy boundary. (6 to 22 inches thick)
Oa3--25 to 59 inches; black (10YR 2/1) muck; 16 percent fiber; 2 percent rubbed; massive; slightly sticky; few pockets of dark grayish brown (10YR 4/2) fine sand; many fine and medium roots; 2.77 percent sulfur; 51.2 mmho/cm conductivity; very strongly acid; gradual smooth boundary. (34 to 45 inches thick)
Cg--59 to 80 inches; dark grayish brown (10YR 4/2) fine sand; common coarse distinct very dark gray (10YR 3/1) masses of organic matter accumulation; single grained; loose; very strongly acid.
TYPE LOCATION: St. Johns County, Florida; about 0.7 mile east of U.S. Highway 1, and 50 feet north of private road along north boundary of St. Augustine Airport. Land Grant 50, T. 6 S., R. 29 E.
RANGE IN CHARACTERISTICS: Sulfur content ranges from 0.75 to 3.25 percent in the Oa horizons. The organic material in all the tiers is dominantly sapric. Conductivity of the saturation extract of the Oa horizons range from 45 to 300 mmho/cm. Reaction of the Oa horizons range from extremely acid to neutral in 0.01M CaC12 in its natural state and from extremely acid to moderately acid after drying. Reaction of the C horizon ranges from extremely acid to moderately alkaline.
The Oa horizon has hue of 5YR to 10YR, value of 2 or 3, chroma of 1 or 2; or it is neutral with value of 2 or 3. Content of mineral material ranges from about 35 to 60 percent. Texture is muck.
The C horizon has hue of 10YR to 5Y, value of 4 to 7, chroma of 1 or 2; or it is neutral with value of 4 to 6. Some pedons have 5 to 20 percent, by volume, sand-size fragments of shell. Texture is sand, fine sand, or loamy fine sand.
COMPETING SERIES: There are no other known series in the same family.
GEOGRAPHIC SETTING: Durbin soils are in narrow to broad tidal marshes and swamps. Slopes are less than 1 percent. They formed in thick deposits of herbaceous plant remains over sandy marine deposits. The climate is humid subtropical. The average annual precipitation ranges from 50 to 60 inches and the average annual temperature ranges from 71 to 73 degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Pellicer and Tisonia series. Both of these soils are on similar positions as Durbin soils. Pellicer soils are mineral throughout. Tisonia soils are organic soils that have clayey material at depths of less than 51 inches.
DRAINAGE AND PERMEABILITY: Very poorly drained; rapid permeability.
USE AND VEGETATION: Durbin soils are used mainly for wildlife habitat. The native vegetation consists of seashore saltgrass, needlegrass rush, smooth cordgrass, and marshy cordgrass.
DISTRIBUTION AND EXTENT: Coastal tidal areas of Peninsular Florida. This series is of small known extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Auburn, Alabama.
SERIES ESTABLISHED: St. Johns County, Florida, 1981.
REMARKS: Diagnostic horizons and features recognized in this pedon:
Histic epipedon - the zone from 0 to 59 inches (Oa1, Oa2, and Oa3 horizons).
Sulfur presence - the zone from 0 to 59 inches (Oa1, Oa2, and Oa3 horizons).
Typic feature - mineral soil at a depth of 59 inches (Cg horizon).
These soils are flooded daily by normal high tides.
This series was formerly mapped as tidal marsh.