LOCATION MOHAWK NYEstablished Series
TAXONOMIC CLASS: Fine-loamy, mixed, active, mesic Mollic Hapludalfs
TYPICAL PEDON: Mohawk silt loam - cultivated. (Colors are for moist soil unless otherwise stated.)
Ap-- 0 to 8 inches; very dark grayish brown (10YR 3/2) moist and crushed or broken, grayish brown (10YR 5/2) dry and crushed, silt loam; strong medium and fine granular structure; friable; many roots; slightly acid; clear smooth boundary. (6 to 9 inches thick.)
BA-- 8 to 11 inches; brown (10YR 4/3) uncrushed, brown (10YR 5/3) crushed, pale brown (10YR 6/3) crushed and dry; silt loam; moderate fine subangular blocky structure; friable; many fine tubular vertical pores without clay linings; many fine and common medium roots; peds have distinct pressure faces but no clay films; many earthworm channels; slightly acid; gradual wavy boundary. (6 to 14 inches thick.)
Bw-- 11 to 19 inches; brown (10YR 4/3) crushed, silt loam; strong fine subangular blocky structure; friable; peds have very dark grayish brown (10YR 3/2) to very dark gray (10YR 3/1) faces without apparent clay films; many fine roots penetrate the peds, which can be suspended on the roots like a string of beads; many fine pores, which have smooth interiors that are like clay coats, neutral; diffuse boundary. (6 to 10 inches thick.)
Bt-- 19 to 30 inches; very dark grayish brown (10YR 3/2) crushed; silt loam; moderate medium subangular blocky structure; parts under slight pressure to strong fine subangular blocks; friable; ped faces are very dark gray (10YR 3/1); when broken, ped interiors are brown (10YR 4/3) to dark grayish brown (10YR 4/2); common black (10YR 2/1) soft shale fragments; thin clay films on 20 percent of ped faces; many fine vertical tubular pores with smooth interiors; common fine roots, few coarse roots; neutral; clear wavy boundary. (8 to 14 inches thick.)
BC-- 30 to 40 inches; very dark grayish brown (10YR 3/2) crushed; heavy silt loam; moderate medium blocky structure arranged in weak very thick plates; firm; ped faces are very dark grayish brown (10YR 3/2) and have thin patchy clay films; broken peds have dark grayish brown (10YR 4/2) interiors; common black (10YR 2/1) soft shale fragments; few coarse roots; slightly alkaline, slightly effervescent; diffuse boundary. (8 to 12 inches thick)
C-- 40 to 72 inches; dark grayish brown (10YR 4/2) loam containing many black (10YR 2/1) shale fragments; the whole crushes to very dark grayish brown (10YR 3/2) silt loam; weak coarse plate like divisions; firm; moderately alkaline, strongly effervescent; coarse roots extend below 45 inches.
TYPE LOCATION: Onondaga County, New York; town of Onondaga; 1-1/2 miles west and 1-3/8 miles south of Split Rock; east side of N - S road, 100 yards south of large dairy barn near crest of broad hill trending northwest-southeast. USGS Camillus, NY topographic quadrangle; Latitude 43 degrees, 00 minutes, 07 seconds N. and Longitude 76 degrees, 15 minutes, 05 seconds W. NAD 1927.
RANGE IN CHARACTERISTICS: Thickness of solum ranges from 24 to 45 inches. Depth to carbonates ranges from 20 to 60 inches. Depth to bedrock is greater than 60 inches. Dark or very dark colors associated with dark colored shale dominate the entire pedon. The C horizon contains more than 1 percent organic matter. In the darkest color pedons, the boundary between A and B horizons is evident only by the change from granular to blocky structure. However, in these pedons the C horizon has 1 percent or less carbon content difference than the uppermost B subhorizon. Clay skins are evident only in the lower subhorizon of Bt. Friable shale fragments, part of which disperse upon mechanical analysis, range from few in the upper horizons to common of some B horizons. Hard gravel and stones range from none to 20 percent of the solum.
The Ap horizon has hues of 10YR or 2.5Y, value of 2 or 3, and chroma of 1 or 2. Texture is silt loam or loam. Structure is granular or subangular blocky parting to granular. Consistence is friable or very friable. Reaction is moderately acid to neutral.
Some pedons have a BA or BE horizon with hue of 10YR or 2.5Y, value of 3 to 6, and chroma of 2 or 3. Texture is silt loam or loam in the fine-earth fraction. Structure is weak or moderate subangular blocky or platy. Consistence is friable or firm. Reaction is moderately acid to neutral
The Bw or Bt horizon has hue of 10YR or 2.5Y, value of 3 or 4, and chroma of 2 or 3, when crushed it has hue of 10YR or 2.5Y, value of 4 or 5, chroma of 2 or 3. Texture is predominantly loam or silt loam, but subhorizons in some pedons may include fine sandy loam or silty clay loam. Structure is moderate or strong, fine to coarse blocky with thin clay skins on none to 20 percent of ped faces in the upper part and 10 to 40 percent in the lower part of the Bt horizon. Consistence is friable, very friable, or firm. Reaction ranges from moderately acid to neutral. The lowest subhorizon is slightly effervescent in some pedons.
The BC horizon, where present, has of 10YR or 2.5Y, value of 3 or 4, and chroma of 2 or 3. Texture is predominantly loam or silt loam, but includes fine sandy loam and silty clay loam in the fine-earth fraction. Structure is weak or moderate, angular or subangular blocky, or platy. Consistence is friable or firm. Reaction is neutral or slightly alkaline.
The C or Cd horizon has hue of 10YR or 2.5Y, value of 3 or 4, chroma of 2 or 3. It is massive or has plate-like divisions. Consistence is firm. Reaction is neutral to moderately alkaline, and slightly to violently effervescent.
COMPETING SERIES: The Dunbridge, Lauramie, Longlois, Lydick, Oneco, and Razort series are members of the same family. None of these has the dark inherited colors and relatively high carbon throughout that characterizes Mohawk. In addition, Dunbridge soils have bedrock above 40 inches, Lauramie and Longlois soils have discontinuities of material within or immediately below the solum, Lydick soils have a thick solum and a sandy C horizon, Oneco soils have limestone bedrock at 40 to 60 inches, and Razort soils formed in alluvium, have rare flooding, and have a thicker solum.
The Baltimore, Blooming, Dowagiac, Neda, Newcomer, Orwood, Sebbo, Taopi, and Waucoma soils are similar, but do not have CEC assigned. None of these has the dark inherited colors and relatively high organic carbon throughout that characterizes Mohawk. Among other related soils, Honeoye and Lima have lighter-colored B and/or C horizons which contain less carbon. Among soils high in dark shale, Manheim has distinct redoximorphic features in the solum, Palatine has bedrock within 40 inches and lacks an argillic horizon, and Herkimer has a coarser water-sorted C horizon.
GEOGRAPHIC SETTING: The Mohawk series is on till plains and till-mantled dissected plateaus. Slope ranges 3 to 15 percent, but may range to 30 percent. The regolith is firm basal till mainly from black soft shale. It is generally calcareous, but of variable lime content, including limestone. The climate is humid and cool temperate. Mean annual precipitation ranges from 30 to 45 inches; mean annual air temperature from 46 degrees to 50 degrees F; and mean growing season, from 130 to 180 days.
GEOGRAPHICALLY ASSOCIATED SOILS: The Mohawk series is the best drained member of a drainage sequence that includes the Manheim, Ilion, and Fonda series. Palatine soils are the moderately deep associates. Herkimer soils are on nearby alluvial fans. Locally Mohawk areas grade into areas of Honeoye, Lansing, and Danley series and their wetter associates.
DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained. The potential for surface runoff is medium to high. Saturated hydraulic conductivity is moderately high to high in the surface layer and subsoil and moderately low to moderately high in the substratum.
USE AND VEGETATION: About 85 percent is cleared, and most of this is used for pasture, hay, corn, and oats. Forested areas have northern hardwoods with sugar maple dominant.
DISTRIBUTION AND EXTENT: New York, in the Mohawk and Black River valleys and locally on the northern edge of the Allegheny Plateau. MLRA's 101 and 140. Total area is moderately extensive.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Amherst, Massachusetts
SERIES ESTABLISHED: Montgomery County, New York, 1908.
REMARKS: Moderately well drained was removed from the series, and areas that are moderately well drained will be considered as inclusions, unless there is a significant acreage to establish a new series.
Diagnostic horizons and features recognized in this profile are:
1. Ochric epipedon - 0 to 8 inches. (Ap).
2. Argillic horizon - 19 to 30 inches. (Bt)
3. Mollic subgroup - has colors of mollic epipedon, but is too thin, only 9 inches. (Ap)