LOCATION KI                      HI

Established Series
Rev. KH-RTG
08/2012

KI SERIES


The Ki series consists of very deep, well drained soils that formed in basic volcanic ash. Slopes range from 2 to 10 percent. The mean annual rainfall is about 1,550 millimeters (61 inches), and the mean annual air temperature is about 13 degrees C. (61 degrees F.).

TAXONOMIC CLASS: Medial, amorphic, isomesic Eutric Thaptic Hapludands

TYPICAL PEDON: Ki medial silt loam, 4 percent slope under grasses and ferns at an elevation of 1,245 meters (4080 feet). (Colors are for moist soil unless otherwise noted. When described on 9/22/98, the soil was dry to 97 centimeters (38 inches) and slightly moist below. The soil temperature was 17 degrees C. (63 degrees F.) at a depth of 51 centimeters (20 inches). All textures are "apparent field textures". pH was determined by adjusting field organic dye values via regression to approximate pH in 1:1 water.)

A--0 to 6 centimeters (0 to 2 inches); black (10YR 2/1) medial loam, very dark grayish brown (10YR 3/2) dry; strong fine and medium granular and strong coarse granular structure; soft to moderately hard, friable, nonsticky and nonplastic; many very fine and fine, and few medium and coarse roots; many very fine and fine interstitial pores; 2 percent strands of Pele's hair; moderately acid (pH 5.8); abrupt wavy boundary. (6 to 15 centimeters (2 to 6 inches) thick)

Bw--6 to 10 centimeters (2 to 4 inches); very dark grayish brown (10YR 3/2) medial loam, dark grayish brown (10YR 4/2) dry; moderate fine granular structure; slightly hard, friable, nonsticky and nonplastic; common very fine and fine roots; many very fine and fine interstitial pores; 25 percent 0.25 to 0.75 centimeter in diameter, round very dark grayish brown (10YR 3/2), soft to hard accretionary lapili; slightly acid (pH 6.4); clear wavy boundary. (3 to 5 centimeters (1 to 2 inches) thick)

C1--10 to 13 centimeters (4 to 5 inches); lithochromic black (N 2/0) ashy very fine sandy loam, black (10YR 2/1) dry; massive; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; many very fine and fine interstitial pores; 5 percent strands of Pele's hair; neutral (pH 6.6); abrupt wavy boundary. (3 to 5 centimeters (1 to 2 inches) thick)

C2--13 to 16 centimeters (5 to 6 inches); lithochromic 70 percent brown (7.5YR 5/3) and 30 percent black (10YR 2/1) gravelly ashy coarse sand, yellowish brown (10YR 5/4) and dark grayish brown (10YR 4/2) dry; single grain; loose when dry or moist, nonsticky and nonplastic; common very fine and fine roots; many very fine and fine interstitial pores; 15 percent pumice-like gravel; neutral (pH 6.6); clear wavy boundary. (3 to 5 centimeters (1 to 2 inches) thick)

2A1--16 to 23 centimeters; (6 to 9 inches) very dark brown (10YR 2/2) and brown (7.5YR 4/4) very gravelly ashy very fine sandy loam; massive with 10 percent moderate medium platy structure; slightly hard, friable, nonsticky and nonplastic; platy structure is moderately hard, friable, nonsticky and non plastic; common very fine and fine roots; many very fine and fine interstitial pores; 40 percent subrounded basaltic gravel; neutral (pH 6.7); diffuse wavy boundary. (5 to 10 centimeters (2 to 4 inches) thick)

2A2--23 to 32 centimeters (9 to 13 inches); black (7.5YR 2.5/1) gravelly ashy fine sandy medial loam, dark brown (7.5YR 3/2) dry; massive; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; many very fine and fine interstitial pores; 30 percent subrounded basaltic gravel; neutral (pH 6.7); abrupt wavy boundary. (5 to 10 centimeters (2 to 4 inches) thick)

2Bw--32 to 39 centimeters (13 to 15 inches); very dark brown (7.5YR 2.5/3) very gravelly medial sandy loam, brown (7.5YR 4/4) dry; massive; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; many very fine and fine interstitial pores; 45 percent subrounded basaltic gravel; neutral (pH 6.8); abrupt wavy boundary. (5 to 8 centimeters (2 to 3 inches) thick)

3A--39 to 47 centimeters (15 to 19 inches); black (10YR 2/1) very gravelly medial sandy loam, very dark brown (7.5YR 2/2) dry; massive; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; many very fine and fine interstitial pores; 45 percent subrounded basaltic gravel; neutral (pH 6.9); abrupt wavy boundary. (8 to 13 centimeters (3 to 5 inches) thick)

3AB--47 to 58 centimeters (19 to 23 inches); very dark brown (10YR 2/2) medial loam, very dark grayish brown (10YR 3/2) dry; massive; soft, very friable, nonsticky and nonplastic; common very fine and fine roots; many very fine and fine interstitial pores; 10 percent subrounded basaltic gravel; neutral (pH 6.9); clear wavy boundary. (8 to 13 centimeters (3 to 5 inches) thick)

3Bw1--58 to 67 centimeters (23 to 26 inches); very dark brown (7.5YR 2.5/2) medial loam, brown (7.5YR 4/4) dry; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores; 5 percent subrounded basaltic gravel; neutral (pH 6.9); clear wavy boundary. (5 to 13 centimeters (2 to 5 inches) thick)

3Bw2--67 to 76 centimeters (26 to 30 inches); very dark brown (7.5YR 2.5/3) very gravelly medial loam, brown (7.5YR 5/4) dry; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores; 35 percent subrounded basaltic gravel; neutral (pH 6.9); clear wavy boundary. (5 to 13 centimeters (2 to 5 inches) thick)

3Bw3--76 to 82 centimeters (30 to 32 inches); black (7.5YR 2.5/1) medial silt loam, dark brown (7.5YR 3/3) dry; massive; slightly hard, friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores; 2 percent subrounded basaltic gravel; neutral (pH 6.9); clear wavy boundary. (5 to 13 centimeters (2 to 5 inches) thick)

3Bw4--82 to 92 centimeters (32 to 36 inches); very dark brown (7.5YR 2.5/2) very gravelly medial loam, dark yellowish brown (10YR 3/4) dry; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores; 45 percent subrounded basaltic gravel; neutral (pH 6.9); clear wavy boundary. (5 to 13 centimeters (2 to 5 inches) thick)

4Bw5--92 to 97 centimeters (36 to 38 inches); very dark brown (7.5YR 2.5/3) medial loam, strong brown (7.5YR 4/6) dry; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores; 2 percent subrounded basaltic gravel; neutral (pH 7.0); clear wavy boundary. (3 to 8 centimeters (1 to 3 inches) thick)

4Bw6--97 to 105 centimeters (38 to 41 inches); very dark brown (7.5YR 2.5/2) very gravelly medial loamy sand; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores; 35 percent subrounded basaltic gravel; neutral (pH 7.0); abrupt wavy boundary. (3 to 8 centimeters (1 to 3 inches) thick)

4C--105 to 110 centimeters (41 to 43 inches); dark reddish brown (2.5YR 2.5/3) extremely gravelly ashy fine sand and extremely gravelly medial sand; single grain; loose when dry or moist, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores; 70 percent subrounded pumice; neutral (pH 7.0); diffuse wavy boundary. (3 to 8 centimeters (1 to 3 inches) thick)

5Bw1--110 to 121 centimeters (43 inches to 48 inches); very dark brown (7.5YR 2.5/2) gravelly medial loam; massive; slightly hard, friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores; 25 percent subrounded basaltic gravel; neutral (pH 7.1); clear wavy boundary. (5 to 15 centimeters (2 to 6 inches) thick)

5Bw2--121 to 131 centimeters (48 to 52 inches); dark brown (10YR 3/3) very gravelly medial very fine sandy loam; massive; slightly hard, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores; 40 percent subrounded basaltic gravel; neutral (pH 7.1); clear wavy boundary. (5 to 15 centimeters (2 to 6 inches) thick)

5Bw3--131 to 152 centimeters (52 to 60 inches); dark brown (7.5YR 3/2) medial silt loam; massive; slightly hard, friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores; 5 percent subrounded basaltic gravel; neutral (pH 7.1); clear wavy boundary. (10 to 40 centimeters (4 to 16 inches) thick)

TYPE LOCATION: Hawaii Volcanoes National Park; from State Hwy. 11 travel Mauna Loa Strip Road 2.3 miles; turn north (right) and follow four wheel drive road 0.05 miles; take 94 degrees magnetic heading east 24 feet to type location; Kilauea Crater Quadrangle; lat. 19 degrees 26 minutes 39.57 seconds N. and long. 155 degrees 18 minutes 41.03 seconds W. (Old Hawaiian Datum measured by GPS PLGR, 250 feet).

RANGE IN CHARACTERISTICS:
Depth to bedrock: 152 to 254 centimeters (60 to 100 inches) or more.
Mean annual soil temperature: 13 to 15 degrees C. (56 to 59 degrees F.).
Soil reaction: Strongly acid to neutral.

A horizon
Texture: Very fine sandy loam, fine sandy loam, or sandy loam, predominantly medial but may be ashy.

B horizon
Hue: 2.5YR to 10YR.
Value: 2 or 3 moist.
Chroma: 1 to 3 moist.
Texture: Medial silt loam, medial loam, or medial sandy loam.
Structure: Granular, subangular blocky, or massive.
Soil reaction: Slightly acid or neutral.
Rock fragments: 0 to 45 percent; control section averages less than 35 percent.

C horizon
Hue: 7.5YR or 10YR, N.
Value: 2 or 3 moist.
Chroma: 2 or 3 moist.
Texture: Ashy coarse sand to ashy very fine sandy loam.
Structure: Single grain or massive.
Soil reaction: Slightly acid to neutral.
Rock fragments: 0 to 40 percent.

COMPETING SERIES: There are no competing series. Similar soils include the Haa and Puiwa series. Haa and Puiwa soils do not have lapili in the upper part of the subsoil, and do not have C horizons (derived from Keanakakoi ash) in the upper part of the soil.

GEOGRAPHIC SETTING: Ki soils formed in material weathered from three main volcanic ash packets: 1790 Keanakakoi base surge and ash falls, Uwekahuna ash, 2,000 to 3,000 years old, and an unnamed ash, about 10,000 years old. Ki soils are mainly on Mauna Loa landforms greater than 10,000 years old at elevations 1,190 to 1,400 meters (3,900 to 4,600 feet). Slopes range from 2 to 10 percent. The mean annual rainfall is 1,500 to 2,000 millimeters (59 to 78 to inches), about 90 percent of which falls between October and May. The mean annual pan evaporation is 1,270 to 1,525 millimeters (50 to 60 inches). The mean annual air temperature is 13 to 17 degrees C. (56 to 62 degrees F.).

GEOGRAPHICALLY ASSOCIATED SOILS: These are the Alahapa, Heake, and Oneula soils. Alahapa and Oneula soils are fragmental soils over `a`a lava. Heake soils are lithic, less than 50 centimeters (20 inches) to pahoehoe lava.

DRAINAGE AND PERMEABILITY: Well drained. Runoff is low. Permeability is rapid.

USE AND VEGETATION: These soils are used for National Park Service land. Vegetation is brackenfern (Pteridium aquilinum var. decompositum), prickly Florida blackberry (Rubus argutus), and various grasses. These soils also occur under trees in Kipuka Ki and Kipuka Puaulu.

DISTRIBUTION AND EXTENT: These soils occur within Hawaii Volcanoes National Park; MLRA 161. This series is of small extent.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.

SERIES ESTABLISHED: Island of Hawaii, Hawaii County, Hawaii, 2012. Proposed 1998. The name is taken from Kipuka Ki.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Andic soil properties - 0 to 150 centimeters (0 to 60 inches).
Soil temperature - borderline isomesic/isothermic. Mean annual air temperature at the National Park HQ (elevation 3970 feet) is about 60 degrees F. Mean summer and mean winter soil temperatures differ by less than 6 degrees C. (iso temperature regime).
Soil moisture - not dry in some or all parts for 90 days or more in most years (Udic moisture regime).
The soil is more than 160 inches deep, but described to 60 inches.

Edit Log: 12/03 KH. Added "ashy" and "medial" modifiers to textures.

ADDITIONAL DATA: Ki NSSL sample S98HI-001-020 from type location.


National Cooperative Soil Survey
U.S.A.