LOCATION MCKENNA                 WA

Established Series
Rev. CJM/CRF/EED
10/2018

MCKENNA SERIES

Landscape--glacial drift plains
Landform--depressions and drainageways
Slope--0 to 5 percent
Parent material--alluvium over glacial drift
Mean annual precipitation--about 1100 mm
Mean annual temperature--about 10 degrees C
Depth class--moderately deep to densic contact
Drainage class--poorly drained
Soil moisture regime--aquic
Soil temperature regime--mesic
Soil moisture subclass--typic

TAXONOMIC CLASS: Loamy-skeletal, mixed, superactive, nonacid, mesic Humic Epiaquepts

TYPICAL PEDON: McKenna gravelly loam, forested

Oi--0 to 3 cm; slightly decomposed plant material consisting of twigs, needles, bark and wood fragments; abrupt wavy boundary

Oe--3 to 8 cm; moderately decomposed plant material consisting of needles, leaves and wood; abrupt wavy boundary

A--8 to 23 cm; gravelly loam, dark gray (10YR 4/1) dry, dark reddish brown (5YR 2/2) moist; weak fine granular structure; soft, very friable, nonsticky and nonplastic; many coarse, medium and fine roots; 20 percent gravel; moderately acid (pH 5.6); abrupt smooth boundary

Bg1--23 to 28 cm; gravelly silt loam, grayish brown (10YR 5/2) dry, dark grayish brown (10YR 4/2) moist; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; few coarse, medium and fine roots; 25 percent gravel; moderately acid (pH 5.6); clear smooth boundary

2Bg2--28 to 48 cm; very gravelly loam, light brownish gray (10YR 6/2) dry, grayish brown (10YR 5/2) moist; moderate medium subangular blocky structure; slightly hard, friable, nonsticky and nonplastic; very few fine roots; 40 percent gravel; moderately acid (pH 5.6); gradual smooth boundary

2Bg3--48 to 79 cm; very gravelly loam, light brownish gray (2.5Y 6/2) dry, dark grayish brown (10YR 4/2) moist; moderate medium subangular blocky structure; hard, firm, slightly sticky and slightly plastic; common medium distinct strong brown (7.5YR 5/8) iron concentrations; 45 percent gravel; moderately acid (pH 5.6); abrupt smooth boundary

2Cd1--79 to 102 cm; dense glacial till that crushes to very gravelly loam, light gray (5Y 7/1) dry, grayish brown (2.5Y 5/2) moist; massive; hard, firm, nonsticky and nonplastic; common medium distinct dark olive gray (5Y 3/2) and yellowish brown (10YR 5/4) iron-manganese masses; 45 percent gravel; moderately acid (pH 5.6); abrupt smooth boundary

2Cd2--102 to 150 cm; dense glacial till that crushes to gravelly silty clay, dark greenish gray (5BG 4/1), gray (N/6) dry; massive; extremely hard, firm, very sticky and very plastic; 30 percent gravel; moderately acid (pH 5.6)

TYPE LOCATION: Kitsap County, Washington; about 11 km south of Port Orchard; 600 m east and 350 m south of the northwest corner of sec. 1, T. 22 N., R. 1 E., Willamette Meridian; Olala, Washington, U.S. Geological Survey quadrangle; latitude 47.429306 north, longitude 122.623 degrees west, WGS 84 (coordinates estimated from PLSS details)

RANGE IN CHARACTERISTICS:
*Mean annual soil temperature--9 to 12 degrees C
*Depth to restriction--50 to 100 cm
*Depth to aquic conditions--0 to 30 cm
*Base Saturation (by NH4OAc)--less than 50 percent in one or more horizons within 100 cm of the soil surface

Particle Size Control Section (weighted average):
*Clay content--10 to 35 percent
*Total rock fragments--35 to 60 percent

O horizon
Thickness 0 to 8 cm

A horizon
Hue--5YR, 7.5YR, 10YR,
Value--2 or 3 moist, 2 to 5 dry
Chroma--1 or 2 moist or dry
Total rock fragments -- 0 to 35 percent
Gravel content--0 to 35 percent
Cobble content --0 to 5 percent
Reaction (pH)--4.5 to 6.0
Thickness--10 to 23 cm

Bg horizon
Hue--7.5YR, 10YR
Value--3 to 5 moist, 5 or 6 dry
Fine-earth texture--silt loam, loam, clay loam
Total rock fragments --15 to 50 percent
Gravel content--15 to 45 percent
Cobble content --0 to 5 percent
Reaction (pH)--5.1 to 6.0
Thickness--10 to 38 cm

2Bg horizon
Hue--10YR, 2.5Y, 5Y
Value--3 to 6 moist, 5 to 8 dry
Chroma--1 or 2, moist or dry
Fine-earth texture--clay loam, loam, silt loam
Total rock fragments--35 to 60 percent
Gravel content--35 to 55 percent
Cobble content --0 to 5 percent
Reaction (pH)--5.1 to 6.0
Thickness--15 to 38 cm thick

2Cd horizons
Hue--10YR, 2.5Y, BG, N
Value--4 to 6 moist, 6 to 8 dry
Chroma--neutral, 1 to 3 moist or dry
Fine-earth texture--sandy loam, loam, clay loam, silty clay loam or silty clay
Total rock fragments--15 to 90 percent
Gravel content--35 to 75 percent
Cobble content--0 to 20 percent
Reaction (pH)--5.6 to 6.5

COMPETING SERIES: There are no competing series.

GEOGRAPHIC SETTING:
Elevation--5 to 150 m
Mean annual precipitation--760 mm to 1500 mm
Mean annual air temperature--9 to 11 C
Frost-free period--150 to 240 days

GEOGRAPHICALLY ASSOCIATED SOILS:
Alderwood, Clallam, Kapowsin--no aquic conditions within 30 cm of the soil surface; on adjacent hills, ridges
Hoypus and Neilton-- no aquic conditions; no densic layer; on adjacent hills and terraces
Bellingham-- aquic conditions; no densic layer; total rock fragment content of less than 15 percent in the particle size control section; on similar landforms

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY:
*Drainage class--Poorly drained
*Depth to perched seasonal water table--at the surface to a depth of 30 cm at times in November to April
*Flooding--none
*Ponding--frequent; long duration
*Saturated hydraulic conductivity (Ksat)--very high in the A, Bg, and 2Bg horizons, very low in the 2Cd horizons

USE AND VEGETATION:
*Use--wildlife habitat, livestock grazing
*Native vegetation--red alder, willow, western red cedar, salmonberry, Douglas spirea, sedges

DISTRIBUTION AND EXTENT: Western Washington; MLRA 2; small extent

SOIL SURVEY REGIONAL OFFICE (SSRO) RESPONSIBLE: Portland, Oregon

SERIES ESTABLISHED: Whatcom County, Washington, 1945

REMARKS:
Diagnostic horizons and other features in this pedon
*Particle Size Control Section--25 to 79 cm
*Ochric epipedon
*Cambic horizon--zone from 8 to 79 cm
*Aquic conditions--zone from 0 to 79 cm
*Episaturation--zone from 0 to 79 cm
*Redoximorphic depletions with chroma of 2 or less--zone from 23 to 79 cm
*Depth to lithologic discontinuity--28 cm
*Depth to densic contact--79 cm

06/2018-Changed from previous classification of loamy-skeletal, mixed, superactive, nonacid, mesic Aquandic Epiaquepts. Existing laboratory data for this series and other geographically associated soils does not reflect the presence of adequate quantities of volcanic glass to support the Aquandic subgroup. The official series description was edited according to SSR01 Technical Note--Content and Format of Official Series Descriptions (revised 11/2017).

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National Cooperative Soil Survey
U.S.A.