LOCATION KAHALII HITentative Series
TAXONOMIC CLASS: ashy, amorphic, isothermic Lithic Udivitrands
TYPICAL PEDON: Kahalii cindery surface, 8 percent slope under scattered shrubs and grasses at an elevation of 823 meters (2,700 feet). Cinders cover about 95 percent of the surface area. (Colors are for moist soil unless otherwise noted. When described on 2/27/98 the soil was dry throughout. The soil temperature was 20 degrees C. (68 degrees F.) at a depth of 23 centimeters (9 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.)
C--0 to 10 centimeters (0 to 5 inches); 75 percent lithochromic black (N 2/0) glassy cinders and 20 percent light yellowish brown (2.5Y 6/4) pumice; extremely gravelly (cindery) coarse sand; single grain; loose moist or dry, nonsticky and nonplastic; few very fine and fine roots; many very fine to coarse interstitial pores; 3 percent Pele's hair; strongly acid (pH 5.4); clear wavy boundary. (2.5 to 12.5 centimeters (1 to 5 inches) thick)
2A--10 to 13 centimeters (4 to 5 inches); black (7.5YR 2/1) gravelly ashy loamy sand, very dark grayish brown (10YR 3/2) dry; moderate medium subangular blocky structure; slightly hard, very friable, nonsticky and nonplastic; many very fine and fine roots; many very fine and fine and few medium interstitial pores; 20 percent subrounded gravel; strongly acid (pH 5.4); clear wavy boundary. (0 to 8 centimeters (0 to 3 inches) thick)
2C--13 to 18 centimeters (5 to 7 inches); 75 percent lithochromic black (10YR 2/1) and 25 percent very dark brown (10YR 2/2) very gravelly ashy coarse sand, 40 percent very dark grayish brown (10YR 3/2) and 30 percent very dark gray (10YR 3/1) and 30 percent dark brown (10YR 3/3) dry; single grain; loose moist or dry, nonsticky and nonplastic; common very fine, fine, and medium roots; many very fine to coarse interstitial pores; 50 percent subrounded gravel; slightly acid (pH 6.3); abrupt wavy boundary. (5 to 10 centimeters (2 to 4 inches) thick)
3Bw--18 to 23 centimeters (7 to 9 inches); very dark brown (7.5YR 2.5/2) very gravelly ashy sandy loam, brown (7.5YR 4/4) dry; weak fine platy structure; slightly hard, very friable, nonsticky and nonplastic; common very fine, fine, and medium roots; many very fine and fine and few medium and coarse interstitial pores; 40 percent subrounded gravel; moderately acid (pH 6.0); abrupt wavy boundary. (0 to 10 centimeters (0 to 4 inches) thick)
3C--23 to 24 centimeters (9 to 9.5 inches); lithochromic black (N 2/0) ashy fine sand, black (N 2/0) dry; moderate fine platy structure; slightly hard, very friable, nonsticky and nonplastic; few very fine and fine roots; few very fine and fine interstitial pores; neutral (pH 6.6); clear broken boundary. (0 to 2.5 centimeters (0 to 1 inch) thick)
4C--24 to 28 centimeters (9.5 to 11 inches); 90 percent lithochromic very dark brown (10YR 2/2) and 10 percent dark reddish brown (5YR 3/3) very gravelly ashy coarse sand, brown (7.5YR 5/4) dry; single grain; loose moist or dry, nonsticky and nonplastic; many very fine to medium roots; many very fine to medium interstitial pores; 85 percent subrounded gravel; neutral (pH 6.6); clear wavy boundary. (2.5 to 15 centimeters (1 to 6 inches) thick)
5Cr--28 to 30 centimeters (11 to 12 inches); slightly weathered pahoehoe; clear broken boundary. (0 to 8 centimeters (0 to 3 inches) thick)
5R--30 centimeters (12 inches); hard pahoehoe bedrock.
TYPE LOCATION: Hawaii Volcanoes National Park; drive on Chain of Craters Road, past the 3,000 feet elevation sign to Kipuka Kahalii parking area; from the information sign describing cinderfall on east side of road, walk west (across road) on a 230 degree heading for 74 meters (240 feet) to type location; Makaopuhi Crater Quadrangle; lat. 19 degrees 20 minutes 52.72 seconds N. and long. 155 degrees 12 minutes 57.31 seconds W. (Old Hawaiian Datum measured by GPS/PLGR, 43 feet.)
RANGE IN CHARACTERISTICS:
Depth to bedrock: 15 to 50 centimeters (6 to 20 inches).
Mean annual soil temperature: 17 to 19 degrees C. (62 to 65 degrees F.).
Rock fragments: The soil surface is covered by 95 percent cinders and pumice.
Placic (ironstone-like) material: Occurs in some pedons.
Loam horizon above 5Cr horizon: Occurs in some pedons.
Soil reaction: Strongly acid to slightly acid.
A horizon
Hue: 7.5YR or 10YR.
Value: 2 or 3 moist.
Chroma: 1 to 3 moist.
Texture: Ashy fine loamy sand, ashy loamy sand, ashy very fine sandy loam, ashy fine sandy loam, ashy sandy loam, ashy loam.
Structure: Granular, subangular blocky, massive.
Rock fragments: 10 to 30 percent.
B horizon
Hue: 7.5YR or 10YR.
Value: 2 or 3 moist.
Chroma: 1 to 4 moist.
Texture: Ashy very fine sandy loam, ashy fine sandy loam, ashy sandy loam, ashy loam.
Structure: Platy or massive.
Rock fragments: 10 to 25 percent.
C horizon
Hue: 5YR to 10YR, N.
Value: 2 or 3 moist.
Chroma: 0 to 4 moist.
Texture: Ashy coarse sand, ashy sand, ashy fine sand, ashy fine loamy sand, ashy loamy sand, ashy very fine sandy loam, ashy fine sandy loam, ashy sandy loam, ashy loam.
Structure: Massive, platy, or single grain.
Rock fragments: 0 to 85 percent.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Kahalii soils are on 200 to 400 year Kilauea pahoehoe flows at elevations of 610 of 975 meters (2,000 to 3,200 feet). Slopes range from 2 to 10 percent. Mean annual rainfall is 1,778 to 2,286 millimeters (70 to 90 inches), with about 90 percent of the rainfall occurring between October and May. Mean annual pan evaporation is 1,524 to 1,778 millimeters (60 to 70 inches). The mean annual air temperature is 17 to 19 degrees C. (62 to 66 degrees F.).
GEOGRAPHICALLY ASSOCIATED SOILS: These are the Kanohina, Nakanui, Puhimau, and Lithic Hapludands soils. These soils have a 1500 kPa water retention of more than 15 percent on air-dried samples. In addition Kanohina soils have isohyperthermic temperature regime, and Nakanui soils have an ustic moisture regime.
DRAINAGE AND PERMEABILITY: Well drained. Runoff is very high. Permeability is rapid in the soil and very slow in the underlying pahoehoe bedrock.
USE AND VEGETATION: These soils are used for National Park Service land. Vegetation is `a`ali`i (Dodonaea viscosa), broomsedge (Andropogon virginicus), bush beardgrass (Schizachyrium condensatum), firetree or faya tree (Myrica faya), molassesgrass (Melinis minutiflora), `ohi`a lehua (Metrosideros polymorpha), and pukiawe (Styphelia tameiameiae).
DISTRIBUTION AND EXTENT: These soils occur within Hawaii Volcanoes National Park; MLRA 161. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES PROPOSED: Island of Hawaii, Hawaii County, Hawaii, 1998. The soil name is from Kipuka Kahalii.
REMARKS: Diagnostic horizons and features recognized in this pedon are:
Andic soil properties - from the soil surface to 28 centimeters (11 inches).
Lithic contact - at 30 centimeters (12 inches).
Soil temperature - mean summer and mean winter soil temperatures differ by less than 6 degrees C.
Soil moisture - not dry in some or all parts for 90 days or more (Udic moisture regime).
Edit Log: 12/03 KH. Added ashy modifier to textures.
Soil reclassified by CJ to correct dual particle size class and address the assignment of mineralogy correctly. Previous classification: Pumiceous or ashy-pumiceous over sandy or sandy-skeletal, amorphic, isothermic Lithic Udivitrands
ADDITIONAL DATA:
Penetrometer measurement: 3Bw horizon = 0.5 to 1 tons/square foot. Measurement was made by inserting penetrometer horizontally into (in situ) soil.