LOCATION KOKEE HIEstablished Series
TAXONOMIC CLASS: Medial, ferrihydritic, isothermic Alic Hapludands
TYPICAL PEDON: Kokee silty clay loam - woodland. (Colors are for moist soil unless otherwise noted. All textures are "apparent field textures".)
A1--0 to 4 inches; dark brown (7.5YR 3/2) silty clay loam, brown (7.5YR 4/2) dry; moderate fine and very fine subangular blocky structure; hard, friable, sticky and plastic; many roots; moderate, delayed effervescence with hydrogen peroxide; very strongly acid (pH 5.0); clear smooth boundary. (4 to 8 inches thick)
A2--4 to 8 inches; dark brown (7.5YR 3/3) silt loam, brown (7.5YR 4/3) dry; weak fine subangular blocky structure; slightly hard, very friable, slightly sticky and slightly plastic; many roots; many fine pores; slight, delayed effervescence with hydrogen peroxide; very strongly acid (pH 4.7); clear smooth boundary. (0 to 5 inches thick)
Bw--8 to 14 inches; dark brown (7.5YR 4/4) silty clay loam, strong brown (7.5YR 4/6) dry; weak fine subangular blocky structure; slightly hard, friable, sticky, plastic, and weakly smeary; many roots; many fine and very fine pores; slight, delayed effervescence with hydrogen peroxide; very strongly acid (pH 4.8); clear smooth boundary. (0 to 6 inches thick)
Bt1--14 to 23 inches; strong brown (7.5YR 4/6) silty clay loam, dark brown (7.5YR 4/4) dry; moderate fine and very fine subangular blocky structure; slightly hard, friable, sticky, plastic and weakly smeary; common roots; many fine pores; thin nearly continuous clay films on peds and in pores; conspicuous yellowish "sugary" coating; weak slickensides; very strongly acid (pH 4.8); gradual smooth boundary. (8 to 12 inches thick)
Bt2--23 to 32 inches; dark brown (7.5YR 4/4) silty clay loam, strong brown (7.5YR 4/6) dry; strong very fine subangular and angular blocky structure; slightly hard, friable, sticky and plastic; common roots; many fine pores; thin patchy clay films; conspicuous yellow "sugary" coatings; weak slickensides; very strongly acid (pH 5.0); clear wavy boundary. (8 to 13 inches thick)
Bt3--32 to 42 inches; dark brown (10YR 4/3) silty clay, brown (7.5YR 4/4) dry; strong fine and very fine angular and subangular blocky structure; hard, firm, very sticky and very plastic; few roots; many fine pores; thin patchy clay films; conspicuous yellow "sugary" coatings; very strongly acid (pH 4.8); clear wavy boundary. (8 to 12 inches thick)
C--42 to 50 inches; hard and soft weathered bedrock; the hard material is gray (5YR 5/1), light gray (N 7/ ) dry, with many black coating in pores; also some red, orange, and light yellow coatings in pores; the soft material is dark brown (7.5YR 4/2) silty clay; firm, sticky and plastic; few roots; many fine pores; very strongly acid (pH 4.8).
R--50 inches; gray (5YR 5/1) and light gray (N 7/ ) bedrock.
TYPE LOCATION: Island of Kauai, Kauai County, Hawaii; Waimea Canyon Quadrangle - 22 degrees 07 minutes 59 seconds north latitude and 159 degrees 39 minutes 23 seconds west longitude.
RANGE IN CHARACTERISTICS: Depth to soft weathered rock ranges from 28 to 56 inches. Depth to bedrock ranges from 40 to 60 inches. Mean annual soil temperature is about 60 F.
The A horizon has hue of 7.5YR or 10YR, value of 2 or 3 and chroma of 2 or 3. The A2 and Bw horizons are not always present.
The Bt horizons have hues of 7.5YR or 10YR, value or 3 or 4 and chroma of 3 through 6. Textures are silty clay loam or silty clay.
COMPETING SERIES: There are no competing series.
Similar soils are the Honolua, Kaneohe, Lolekaa, Makawao, and Waikane series. Honolua soils are silty clay throughout the solum and have thick patchy clay films in the argillic horizon. Kaneohe soils are silty clay throughout the solum and have 2.5YR or 5YR hue in the B horizon. Lolekaa soils have hues of 10YR throughout the solum and have isohyperthermic soil temperature. Makawao soils have 2.5 YR or 5YR hues in the B horizon. Waikane soils are silty clay throughout the solum and have 5YR hues in the B horizons.
GEOGRAPHIC SETTING: The Kokee soils are on dissected uplands at elevations of 3,400 to 4,200 feet. Slopes range from 0 to 70 percent but are dominantly between 25 and 60 percent. The soils formed in residuum from basic igneous rocks probably with some additions of volcanic ash and/or ejecta. Annual rainfall is from 60 to 70 inches with nearly daily afternoon cloud cover. Average January temperature is about 53 degrees F.; and average July temperature is about 65 degrees F. Mean annual temperature is about 6O degrees F.
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Kunuweia soils and Paaiki soils. Kunuweia soils have ironstone concretions and plinthite. Paaiki soils do not have an argillic horizon and have moderate structure in the lower part of the control section.
DRAINAGE AND PERMEABILITY: Well drained; medium to rapid runoff depending on slope; moderately rapid permeability.
USE AND VEGETATION: Used for watershed and recreation. Vegetation consists of ohia lehua (Metrosideros collina), yellow foxtail (Setaria geniculata), koa (Acacia koa), formosa koa (Acacia confusa), false staghorn fern (Dicranopteris linearis), orchardgrass (Dactylis glomerata), paspalum (Paspalum sp.), rattailgrass (Sporobolus africanus), plantain (Plantago lanceolata), uki uki (Dianella sp.), fire bush (Myrica faya), redwood (Sequoia sempervirens), and uki (Gahnia gahniformis).
DISTRIBUTION AND EXTENT: Island of Kauai, Hawaii. Approximately 6,100 acres in extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California
SERIES ESTABLISHED: Island of Kauai, Kauai County, Hawaii, 1971.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
umbric epipedon- The zone from the surface to 8 inches (A1, A2)
argillic horizon- The zone from 14 to 42 inches (Bt1, Bt2, Bt3)
lithic contact- The boundary at 50 inches (R)