LOCATION PINEKNOT                MO

Tentative Series
DMM-SGM-KLS
08/2025

PINEKNOT SERIES

The Pineknot series consist of very deep, well or moderately well drained soils formed in acidic loamy hillslope sediments over highly weathered clayey or gravelly clay residuum from dolomite. These nearly level to strongly sloping soils are on uplands of the Ozark Highlands. Slopes range from 1 to 15 percent. The mean annual soil temperature is about 14 degrees Celsius. Mean annual precipitation is about 1118 millimeters.

TAXONOMIC CLASS: Fine-loamy over clayey, siliceous over mixed, subactive, mesic Typic Paleudults

TYPICAL PEDON: Pineknot silt loam, on a 7 percent slope in a mixed shortleaf pine-oak woodland at an elevation of 315 meters. (Colors are for moist soil unless otherwise stated.)

Oi--0 to 5 centimeters; slightly decomposed pine and oak forest litter.

A--5 to 15 centimeters; dark yellowish brown (10YR 3/4) silt loam, yellowish brown (10YR 5/4) dry; weak very fine subangular blocky; very friable; common fine, medium and coarse roots; many fine interstitial pores; 10 percent subangular chert gravels; very strongly acid (pH 5.0); clear smooth boundary. (Thickness of the A horizon is 5 to 28 centimeters.)

Bt1--15 to 24 centimeters; yellowish red (5YR 4/6) gravelly silt loam, moderate fine subangular blocky; friable; common fine, medium and coarse roots; many fine tubular pores; few distinct reddish brown (5YR4/4) clay films on faces of peds; 10 percent subangular chert gravel and 5 percent subangular chert cobbles; very strongly acid (pH 4.8); clear smooth boundary.

Bt2--24 to 34 centimeters; yellowish red (5YR 5/6) silt loam, moderate fine subangular blocky; friable; few fine, medium and coarse roots; many fine tubular pores; few distinct reddish brown (5YR 5/4) clay films on faces of peds; 10 percent subangular chert gravel; very strongly acid (pH 4.8); clear smooth boundary.

Bt3--34 to 44 centimeters; red (2.5YR 4/6) silty clay loam, moderate fine subangular blocky; firm; few fine, medium and coarse roots; common fine tubular pores; common faint red (2.5YR 4/6) clay films on faces of peds; 10 percent subangular chert gravel; very strongly acid (pH 4.9); clear smooth boundary. (Combined thickness of the Bt horizon is 15 to 48 centimeters.)

2Bt4--44 to 65 centimeters; red (10R 4/6) clay, moderate fine angular blocky; very firm; very few very fine roots; few fine tubular pores; many faint red (2.5YR 4/6) clay films on faces of peds; 2 percent subangular chert gravel; very strongly acid (pH 4.7); gradual smooth boundary.

2Bt5--65 to 86 centimeters; red (10R 4/6) gravelly clay, moderate fine and medium angular blocky; very firm; very few very fine roots; very few fine tubular pores; many faint red (2.5YR 4/6) clay films on faces of peds; 25 percent subangular chert gravel; very strongly acid (pH 4.7); gradual smooth boundary.

2Bt6--86 to 126 centimeters; red (10R 4/6) clay, strong medium angular blocky; very firm; very few very-fine roots; very few fine tubular pores; many faint red (2.5YR 4/6) clay films on faces of peds; 10 percent subangular chert gravel; very strongly acid (pH 4.6); gradual wavy boundary.

2Bt7--126 to 200 centimeters; red (10R 4/6) gravelly clay, moderate medium angular blocky; very firm; very few fine tubular pores; few faint red (2.5YR 4/6) clay films on faces of peds; 25 percent subangular chert gravel; very strongly acid (pH 4.8); (Combined thickness of the 2Bt horizon is 60 to 159 centimeters.)

TYPE LOCATION: Shannon County, Missouri; located about 4 miles south and 1 mile east of Birch Tree; 1469 feet north and 1590 feet east of the southwest corner of section 11, T. 26 N., R. 5 W.; USGS Birch Tree topographic quadrangle; lat. 36.9337634 degrees and long. -91.47047888 degrees, WGS84.

RANGE IN CHARACTERISTICS:
Surface fragments: 0 to 40 percent
Gravel size surface fragments: 0 to 35 percent
Cobble size surface fragments: 0 to 5 percent
Stone size surface fragments: 0 to 5 percent
Boulder size surface fragments: 0 to 5 percent
Depth to argillic horizon: 10 to 36 centimeters
Depth to the base of the argillic horizon: 152 to 211 centimeters
Reaction: extremely acid to moderately acid

A, Ap or AB horizon:
Hue: 7.5YR to 10YR
Value: 3 to 4
Chroma: 2 to 4
Texture: silt loam, loam, or their gravelly analogues
Rock fragment content: 5 to 34 percent chert or sandstone gravel and 0 to 5 percent chert or sandstone cobbles, stones, and/or boulders

AE, EA, E or BE horizon:
Hue: 7.5YR to 10YR
Value: 4 to 6
Chroma: 2 to 4
Texture: silt loam, loam, or their gravelly analogues
Rock fragment content: 5 to 34 percent chert or sandstone gravel and 0 to 5 percent chert or sandstone cobbles, stones, and/or boulders

Bt horizon:
Hue: 2.5YR to 10YR
Value: 4 to 6
Chroma: 3 or 6
Texture: silt loam, loam, silty clay loam or their gravelly analogues
Rock fragment content: 0 to 34 percent chert or sandstone gravel and 0 to 5 percent chert or sandstone cobbles, stones, and/or boulders

2Bt horizon:
Hue: 10R to 10YR
Value: 4 to 6
Chroma: 3 to 8
Texture: silty clay, clay or their gravelly analogues
Rock fragment content: 0 to 25 percent chert or sandstone gravel and 0 to 5 percent cobbles, stones, and/or boulders

3Bt horizon (where present):
Hue: 2.5YR to 10YR
Value: 3 to 6
Chroma: 3 to 8
Texture: silty clay, clay or their gravelly, very gravelly, extremely gravelly analogues
Rock fragment content: 10 to 70 percent chert or sandstone gravel and 0 to 5 percent cobbles, stones, and/or boulders

COMPETING SERIES: This is the Watahala series. Watahala soils formed in residuum from chert or cherty limestones over residuum from more pure limestone. The extent of the Watahala series occurs in MLRA 128 and 147, the Appalachian Ridges and Valleys areas of Virginia and northern Tennessee.

GEOGRAPHIC SETTING:
Parent material--loess combined with silty, loamy, or gravelly hillslope sediments over clayey residuum from dolomite of Ordovician age.
Landform--Summits and shoulders of ridges
Slope--1 to 15 percent
Elevation--244 to 427 meters above sea level
Mean annual air temperature--12 to 14 degrees C
Mean annual precipitation--1016 to 1168 millimeters

GEOGRAPHICALLY ASSOCIATED SOILS: These are Captina, Clarksville, Coulstone, Fanchon, Firebaugh, Macedonia, Poynor, Scholten and Tonti soils. The Captina, Tonti, Scholten and Firebaugh soils have a fragipan or a fragic horizon and can occur within the same map unit or adjacent to the Pineknot series. The Fanchon and Macedonia series are fine-loamy or fine particle size class and occur within the same map unit or adjacent to the Pineknot series. The Clarksville, Coulstone and Poynor series are loamy-skeletal or loamy-skeletal over clayey particle size class and are on side slopes or adjacent to the Pineknot series.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
Drainage class--well or moderately well drained
Saturated hydraulic conductivity--1.4 to 14 micrometers per second
Surface runoff potential--low to medium

USE AND VEGETATION:
These soils are used for the production of timber, wildlife habitat, and related natural resources. Some areas are used for pasture and hayland. Native vegetation is mixed conifer-deciduous woodlands. The overstory in most areas consists of shortleaf pine, black oak, scarlet oak, white oak, post oak, pignut hickory, and black hickory. The understory contains blueberries, tick-trefoils, lespedezas, asters, goldenrods, mixed grasses, upland sedges and various other woodland forbs and vines indicative of acidic environments.

DISTRIBUTION AND EXTENT:
Physiographic Division--Interior Highlands
Physiographic Province--Ozark Plateau
Physiographic sections-- Springfield-Salem plateaus
MLRA--Ozarks Highland (MLRA 116A)
LRR--East and Central Farming and Forest Region (N); southern Missouri
Extent-limited

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Salina, Kansas

SERIES PROPOSED: Shannon County, Missouri, 2025.

REMARKS:
Particle-size control section - the zone from a depth of 10 to 100 centimeters.
Series control section - 0 to 200 centimeters.
Diagnostic horizons and features recognized in this pedon include:
Ochric epipedon - the zone from the surface of the soil to a depth of 5 to 33 centimeters (A, E, EA, AE, AB, BA, BE horizons).
Albic horizon, where present the zone from 10 to 41 centimeters.
Argillic horizon - the zone from 15 to 200 centimeters (Bt and 2Bt and 3Bt horizons).
Strongly contrasting particle size class (lithologic discontinuity) occurs at a depth of 39 centimeters for the typical pedon. The range is from 28 to 76 centimeters and the average is 45 centimeters.

The typical pedon has a base saturation of 17 percent at the critical depth. The base saturation for this series ranges from 6 to 20 percent with an average of 12 percent.

Pineknot soils were previously mapped as Macedonia, Fanchon and Poynor series. Site and pedon ID 2017MO203204 represents the typical pedon.

ADDITIONAL DATA: Characterization data is available from the KSSL for the following pedons:

2017MO203102, 1996MO091165, 1999MO035005

Additional lab data from the University of Missouri Soil Health Assessment Center is available for the following pedons:

2017MO035001, 2017MO035108, 2017MO203204

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National Cooperative Soil Survey
U.S.A.