LOCATION QUANADUCK CT
+ RI
Tentative series
Rev. DAS/SJM
4/07
QUANADUCK
SERIES
The Quanaduck series consists of very deep, subaqueous soils on mainland coves.
The Quanaduck soils are formed in loamy marine deposits underlain by sandy or
sandy-skeletal deposits. Slope ranges from 0 to 2 percent, mean annual air
temperature is about 10 degrees C., and mean annual precipitation is about 1142
mm.
TAXONOMIC CLASS: Coarse-loamy over sandy or sandy-skeletal, aniso, mixed, superactive, nonacid, mesic Sulfic Fluvaquents
TYPICAL PEDON: Quanaduck silt loam on a south facing, 2
percent slope in a mainland cove under 1.2 m of estuarine water (Colors are for
moist soil).
Ag—0 to 30 cm;
black (N 2.5/) silt loam; dark gray (5Y 4/1) dry; massive; very fluid; 20
percent herbaceous fibers, 1 percent rubbed; sulphurous odor; strongly saline
(30 ppt); moderately alkaline (pH 8.2); strongly acid (pH 5.5) after 8 weeks;
clear boundary.
ACg—30 to 39 cm; black (N 2.5/) silt loam; very dark grayish brown (10YR 3/2) dry; massive; moderately fluid; 20 percent herbaceous fibers, 0 percent rubbed; 1 percent gravels; sulphurous odor; strongly saline; slightly alkaline (pH 7.6); slightly acid (pH 6.4) after 8 weeks; clear boundary.
Cg1—39 to 46 cm; 50 percent dark grayish brown (10YR 4/2) and 50 percent very dark greenish gray (10Y 3/1) sandy loam; dark gray (10YR 4/1) dry; massive; moderately fluid; 20 herbaceous fiber, 0 percent rubbed; 7 percent gravels; sulphurous odor; strongly saline; slightly alkaline (pH 7.6); slightly acid (pH 6.4) after 8 weeks; clear boundary.
Cg2—46 to 54 cm; very dark greenish gray (10Y 3/1) coarse sand; dark grayish brown (10YR 4/2) dry; massive; nonfluid; 5 percent herbaceous fibers, 0 percent rubbed; 6 percent gravels; sulphurous odor; strongly saline; slightly alkaline (pH 7.8); moderately acid (pH 5.9) after 8 weeks; abrupt boundary.
Cg3—54 to 58 cm; dark greenish gray (5G 4/1) gravelly coarse sand; grayish brown (10YR 5/2) dry; single grain; nonfluid; 2 percent herbaceous fibers, 0 percent rubbed; 15 percent gravels; sulphurous odor; strongly saline; moderately alkaline (pH 8.0); moderately acid (pH 5.9) after 8 weeks; abrupt boundary. (Combined thickness of the Cg horizons is about 10 to 20 cm)
Agb—58 to 66 cm; very dark greenish gray (10Y 3/1) coarse sand; light olive brown (2.5Y 5/3) dry; massive; nonfluid; 5 percent herbaceous fibers, 0 percent rubbed; 14 percent gravels; sulphurous odor; strongly saline; slightly alkaline (pH 7.6); moderately acid (pH 5.6) after 8 weeks; gradual boundary.
Cg’1—66 to 72 cm; very dark greenish gray (10Y 3/1) gravelly coarse sand; light brownish gray (2.5Y 6/2) dry; single grain; nonfluid; 2 percent herbaceous fibers, 0 percent rubbed; 26 percent gravels; sulphurous odor; strongly saline; slightly alkaline (pH 7.4); moderately acid (pH 6.0) after 8 weeks; abrupt boundary.
Cg’2—72 to 82 cm; dark greenish gray (10GY 4/1) loamy coarse sand; light bluish gray (5PB 7/1) dry; single grain; nonfluid; 8 percent gravels; sulphurous odor; strongly saline; slightly alkaline (pH 7.8); strongly acid (pH 5.5) after 8 weeks; abrupt boundary.
Cg’3—82 to 86 cm; 50 percent dark greenish gray (10Y 4/1) and 50 percent dark greenish gray (10GY 4/1) coarse sandy loam; light greenish gray (10Y 7/1) dry; single grain; nonfluid; 7 percent gravels; sulphurous odor; slightly alkaline (pH 7.6); extremely acid (pH 4.0) after 8 weeks; strongly saline; abrupt boundary. (Combined thickness of Cg’ horizons is about 5 to 20 cm)
2Cgb1—86 to 107 cm; gray (N 5/) silt loam; light gray (5Y 7/1) dry; massive; nonfluid; 5 percent gravels; strongly saline; slightly alkaline (pH 7.6); slightly acid (pH 6.4) after 8 weeks; clear boundary.
2Cgb2—107 to 120 cm; dark gray (2.5Y 4/1) sandy loam; light gray (2.5Y 7/1) dry; massive; nonfluid; 14 percent gravels; strongly saline; slightly alkaline (pH 7.8); moderately acid (pH 5.8) after 8 weeks; gradual boundary.
2Cgb3—120 to 155 cm; dark gray (2.5Y 4/1) silt loam; light gray (5Y 7/1) dry; massive; nonfluid; 13 percent gravels; strongly saline; slightly alkaline (pH 7.8); moderately acid (pH 6.0) after 8 weeks. (Combined thickness of the 2Cgb horizons is about 20 to 70 cm)
TYPE LOCATION: New London County, Connecticut; located about 2305 feet southeast of the Barn Island boat launch and 6860 feet west of the intersection of Green Haven Road and Osbrook Point Road, in a cove, USGS Watch Hill topographic quadrangle; lat. 41 degrees 20 minutes 7.9 seconds N. and long. 71 degrees 52 minutes 3.0 seconds W., NAD 83.
RANGE IN CHARACTERISTICS: The soils are permanently submerged. All horizons have a pH of slightly alkaline through moderately alkaline and a pH of ultra acid through slightly acid after 8 weeks incubation. One or more horizons below 50 cm and within 100 cm of the soil surface have a pH of 4.0 or less after 8 weeks incubation. Depth to first lithologic discontinuity ranges from 80 to 100 cm. Electrical conductivity is >16 mmhos/cm and salinity is >18 ppt (strongly saline) throughout the profile.
The Ag and ACg horizons, when present, have hues of N, 2.5Y, 10Y or 10YR, value of 2.5 through 4, and chroma of 0 through 2. Textures are muck silt loam, silt loam, fine sandy loam and sandy loam. Gravel content is 0 to 10 percent. Organic matter is 5 to 15 percent. Herbaceous fibers are 0 to 20 percent unrubbed and 0 to 5 percent rubbed. Consistence is moderately fluid or very fluid. Sulphurous odor is present.
The Cg horizon has hue of N, 5G, 2.5Y, 10Y or 10GY, value of 3 through 6, and chroma of 0 or 1. Textures are sandy loam through coarse sand along with gravelly analogs. Gravel content is 0 to 30 percent. Consistence is nonfluid.
The Agb horizon has hue of 10Y or 2.5Y, value of 3, and chroma of 1. Textures are mucky fine sandy loam through coarse sand along with gravelly analogs. Gravel content is 0 to 20 percent. Herbaceous fibers are 0 to 10 percent unrubbed and 0 to 5 percent rubbed. Organic matter is 5 to 15 percent. Consistence is slightly fluid through nonfluid. Sulphurous odor is present.
The 2Cgb horizon has hue of N or 2.5Y, value of 4 or 5, and chroma of 0 or 1. Textures are silt loam and sandy loam along with gravelly analogs. Gravel content is 0 to 20 percent. Consistence is nonfluid.
COMPETING
SERIES: There are no competing
series in the same family. The Tizzard soils are in related families.
The Tizzard series has a sandy over loamy particle-size control section and
siliceous mineralogy class.
GEOGRAPHIC
SETTING: The Quanaduck soils are
permanently submerged with salt or brackish water in areas adjacent to mainland
coves. Slope ranges from 0 to 5 percent. The soils formed in loamy material
over sandy or sandy skeletal marine sediments and can be found up to 2 meters
deep under water.
GEOGRAPHICALLY
ASSOCIATED SOILS: These are the Anguilla
(T), Napatree (T), Wamphassuc (T), and Wequetequock (T) Wequetequock (T) soils.
DRAINAGE
AND SATURATED HYDRAULIC CONDUCTIVITY:
Subaqueous, peraquic moisture regime, high to very high saturated hydraulic
conductivity. Soil is permanently submerged with salt or brackish water.
USE
AND VEGETATION: This soil
supports submerged aquatic vegetation and wildlife habitats. The area is used by recreational fishermen
for the harvest of crabs. In addition fishing is commonplace and the species
found in the area are smelt, small cod, flounder, scup, menhaden, and white
perch. Some areas are vegetated with native rooted and floating algae
and eelgrass (Zostera marina). Vegetative
cover ranges from 0 to 35 percent.
DISTRIBUTION
AND EXTENT: Permanently submerged inland
bay coves in northeastern
MLRA
OFFICE RESPONSIBLE:
SERIES
PROPOSED:
REMARKS: The Keys to Soil Taxonomy, Tenth Edition, 2006 states
that the horizontal boundaries of soil are areas where the soil grades into
deep water (typically less than 2.5 m). This subaqueous series is being
proposed in areas previously mapped as water in the Connecticut Soil Survey.
Using the proposed taxonomy for subaqueous soils, the series classifies as a
coarse-loamy over sandy or sandy-skeletal, aniso, mixed, superactive, nonacid,
mesic Sulfic Fluviwassents.
Diagnostic horizons and features in this
pedon include:
1. Peraquic feature - positive soil water
potential (permanently submerged) at the soil surface (under 120 cm of salt
water).
2. Particle-size control section – the zone
from 25 to 100 cm.
3. Sulfidic materials – the zone from 82 to
86 cm.
4. Lithologic discontinuity – contrasting soil
materials at 86 cm.
5. Buried soil feature – the zone from 58 to
66 cm (the Agb horizon).
6. Gleyed horizons – the zone from 0 to 155
cm.
ADDITIONAL DATA: Pedon sample S05CT011005 New London County,
Connecticut, by NSSL,
National Cooperative Soil Survey