LOCATION MANU HI
Established Series
Rev. KH-RTG
06/2012
MANU SERIES
The Manu series consists of moderately deep, moderately well drained soils formed in volcanic ash deposited over pahoehoe lava. Slopes range from 2 to 10 percent. The mean annual rainfall is about 2,489 millimeters (98 inches), and the mean annual air temperature is about 16 degrees C. (61 degrees F.).
TAXONOMIC CLASS: Ashy, amorphic, isothermic Aquic Hapludands
TYPICAL PEDON: Manu medial silt loam, 4 percent slope under rain forest at an elevation of 1,189 meters (3,900 feet). (Colors are for moist soil unless otherwise noted. When described on 5/11/97 the soil was moist throughout. 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 8 centimeters (0 to 3 inches); black (7.5YR 2.5/1) medial silt loam; moderate medium subangular blocky structure; slightly hard, friable, slightly sticky and slightly plastic, weakly smeary; many very fine and fine and few medium, coarse, and very coarse roots; many very fine and fine interstitial and tubular pores; very strongly acid (pH 5.0); abrupt wavy boundary. (8 to 15 centimeters (3 to 6 inches) thick)
C1--8 to 10 centimeters (3 to 4 inches); lithochromic black (7.5YR 2.5/1) extremely gravelly ashy sandy loam; massive; soft, very friable, nonsticky and nonplastic; common very fine and fine and few medium, coarse, and very coarse roots; many very fine and fine interstitial pores; 90 percent rounded pyroclastic gravel; slightly acid (pH 6.2); abrupt wavy boundary. (2.5 to 5 centimeters (1 to 2 inches) thick)
2C2--10 to 16 centimeters (4 to 6 inches); lithochromic very dark grayish brown (10YR 3/2) ashy loam; weak medium subangular blocky structure; hard, friable, slightly sticky and slightly plastic, weakly smeary; common very fine and fine and few medium, coarse and very coarse roots; common very fine and fine interstitial pores; few fine distinct dark yellowish brown (10YR 4/6) threads of redox concentrations in root channels and pores; slightly acid (pH 6.2); clear broken boundary. (0 to 8 centimeters (0 to 3 inches) thick)
3C3--16 to 24 centimeters (6 to 9 inches); lithochromic 50 percent very dark brown (10YR 2/2) and 50 percent black (N 2/0) very gravelly ashy sand; massive; soft, very friable, nonsticky and nonplastic; common very fine to medium roots; many very fine and fine interstitial pores; 50 percent subrounded pyroclastic gravel; slightly acid (pH 6.3); clear wavy boundary. (5 to 8 centimeters (2 to 3 inches) thick)
4Bw--24 to 27 centimeters (9 to 11 inches); very dark brown (7.5YR 2.5/2) ashy sandy loam; massive; slightly hard, very friable, moderately sticky and moderately plastic; few very fine and fine roots; many very fine and fine interstitial pores; 5 percent subrounded gravel; neutral (pH 6.7); abrupt wavy boundary. (0 to 2.5 centimeters (0 to 1 inch) thick)
4C1--27 to 33 centimeters (11 to 13 inches); lithochromic very dark grayish brown (10YR 3/2) ashy loamy sand; massive; slightly hard and hard, friable, nonsticky and nonplastic; few very fine and fine roots; common very fine and fine interstitial pores; common fine distinct dark yellowish brown (10YR 4/6) threads of redox concentrations in root channels and pores; neutral (pH 6.7); abrupt wavy boundary. (5 to 8 centimeters (2 to 3 inches) thick)
5C2--33 to 39 centimeters (13 to 15 inches); lithochromic 92 percent very dark brown (10YR 2/2) and 5 percent black (N 2/0) and 3 percent red (10R 4/6) ashy loamy fine sand; massive; soft and slightly hard, very friable, nonsticky and nonplastic; few very fine and fine roots; common very fine and fine interstitial pores; neutral (pH 6.9); abrupt wavy boundary. (0 to 5 centimeters (0 to 2 inches) thick)
6A--39 to 42 centimeters (15 to 16 inches); black (N 2/0) ashy silt loam; massive; soft, very friable, slightly sticky and slightly plastic, moderately smeary; few very fine, fine, and medium roots; many very fine, fine, and medium interstitial pores; neutral (pH 6.9); abrupt wavy boundary. (0 to 2.5 centimeters (0 to 1) inch thick)
6Bw--42 to 46 centimeters (16 to 18 inches); very dark brown (7.5YR 2.5/2) ashy silt loam; massive; slightly hard and hard, friable, moderately sticky and moderately plastic; few very fine and fine roots; many very fine and fine interstitial pores; neutral (pH 6.9); abrupt wavy boundary. (0 to 5 centimeters (0 to 2 inches) thick)
6C1--46 to 51 centimeters (18 to 20 inches); lithochromic 50 percent black (10YR 2/1) and 50 percent very dark brown (10YR 2/2) ashy loamy sand; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores; 10 percent subrounded pyroclastic gravel; neutral (pH 7.1); abrupt wavy boundary. (0 to 5 centimeters (0 to 2 inches) thick)
6C2--51 to 53 centimeters (20 to 21 inches); lithochromic very dark brown (7.5YR 2.5/3) very gravelly ashy sandy loam; massive; soft, very friable, slightly sticky and slightly plastic; few very fine and fine roots; many very fine and fine interstitial pores; few fine distinct dark yellowish brown (10YR 4/6) threads of redox concentrations in root channels and pores; 50 percent subrounded pyroclastic gravel; neutral (pH 7.1); clear wavy boundary. (0 to 2.5 centimeters (0 to 1 inch) thick)
6C3--53 to 65 centimeters (21 to 25 inches); lithochromic very dark grayish brown (10YR 3/2) very gravelly ashy loamy sand; massive; soft, very friable, nonsticky and nonplastic; few very fine and fine roots; many very fine and fine interstitial pores; 50 percent subrounded pyroclastic gravel; neutral (pH 7.1); clear wavy boundary. (0 to 13 centimeters (0 to 5 inches) thick)
7C4--65 to 81 centimeters (25 to 32 inches); reticulite, pumice-like volcanic glass; few very fine and fine roots; neutral (pH 7.2); clear wavy boundary. (0 to 18 centimeters (0 to 7 inches) thick)
8C5--81 to 86 centimeters (32 to 34 inches); very dark gray (10YR 3/1) ashy silt loam; massive; slightly hard, friable, weakly smeary, slightly sticky and slightly plastic; few very fine and fine roots; common very fine and fine interstitial pores; 2 percent Pele's hair; common fine prominent dark yellowish brown (10YR 4/6) threads of redox concentrations; neutral (pH 7.2); abrupt wavy boundary. (0 to 5 centimeters (0 to 2 inches) thick)
9R--86 centimeters (34 inches); hard pahoehoe bedrock.
TYPE LOCATION: Hawaii Volcanoes National Park; from main entrance take immediate left after toll booth and continue to stop sign; turn left and follow road less than 1/4 mile to where powerline crosses road; walk under powerline and climb steep bank to north; follow powerline 5 meters (17 feet) to type location; Kilauea Crater Quadrangle; lat. 19 degrees 25 minutes 36.29 seconds N. and long. 155 degrees 15 minutes 05.53 seconds W. (Old Hawaiian Datum measured by GPS/PLGR, 89 feet).
RANGE IN CHARACTERISTICS:
Depth to bedrock: 50 to 100 centimeters (20 to 40 inches).
Mean annual soil temperature: 15 to 17 degrees C. (59 to 63 degrees F.).
Buried A horizons: Occur in most pedons.
Redox concentrations: Occur in most pedons.
Brittle horizons: Occur in some pedons.
Soil Reaction: Strongly acid to neutral.
A horizon
Hue: 7.5YR or 10YR.
Value: 2 or 3 moist.
Texture: Medial loam or medial silt loam.
Structure: Granular or subangular blocky.
Rock fragments: 0 to 10 percent.
C horizon
Hue: 7.5YR, 10YR, 10R, or N.
Value: 2 to 4 moist.
Chroma: 1 to 6 moist.
Texture: Ashy coarse sand, ashy sand, ashy loamy sand, ashy loamy fine sand, ashy sandy loam, or ashy loam.
Rock fragments: 0 to 90 percent in individual horizons; control section averages 5 to 30 percent.
COMPETING SERIES: There are no competing series.
GEOGRAPHIC SETTING: Manu soils are on Kilauea pahoehoe lava flows less than 750 years old at elevations of 1,158 to 1,219 meters (3,800 to 4,000 feet). Slopes range from 2 to 10 percent. The mean annual rainfall is 2,032 to 3,048 centimeters (80 to 120 inches), with about 80 percent of the rainfall occurring between October and May. The mean annual pan evaporation is 1,397 to 1,651 centimeters (55 to 65 inches). The mean annual air temperature is 14 to 17 degrees C. (58 to 62 degrees F.).
GEOGRAPHICALLY ASSOCIATED SOILS: These are the
Halemaumau,
Heake, and
Puhimau soils. Halemaumau soils are ustic and have accretionary lapili and reticulite. Heake and Puhimau soils are lithic, less than 50 centimeters (20 inches) to bedrock.
DRAINAGE AND PERMEABILITY: Moderately well drained. Runoff is very low. Permeability is rapid in the soil and very slow in the underlying pahoehoe bedrock.
USE AND VEGETATION: The soils are used for National Park Service land. Vegetation is wawaiiole or club moss (Lycopodium cernuum), uluhe or false staghorn fern (Dicranopteris linearis), ohia lehua (Metrosideros polymorpha), and hapuu pulu or tree fern (Cibotium glaucum).
DISTRIBUTION AND EXTENT: These soils are within and adjacent to Hawaii Volcanoes National Park; MLRA 159A. The series is of small extent.
MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.
SERIES ESTABLISHED: Island of Hawaii, Hawaii County, Hawaii, 1949.
REMARKS: Diagnostic horizons and features recognized in this horizon:
Andic soil properties - from 0 to 86 centimeters (0 to 34 inches).
Umbric epipedon - from the soil surface to 64 centimeters (25 inches).
Soil temperature - mean summer and the 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).
FCC Classification: L'Lx.
Edit log: 12/03 KH. Added "medial" and "ashy" modifiers to textures.
3/01 KH. Changed horizon designation 8C5 from 8Cg. Changed runoff from high to low.
9/99 KH. Moved type location to better represent the soil. Reclassified soil based on changes in Taxonomy and new lab data. Was Medial, isothermic Hydric Dystrandepts.
ADDITIONAL DATA: Manu NSSL sample S97HI-001-008 from type location.
Penetrometer measurements made by inserting penetrometer horizontally into "in situ" soil:
A horizon = 0.2 tons/square foot
C1 horizon = 1.25 tons/square foot
2C2 horizon = 1.5 to 3 tons/square foot
3C3 horizon = 0.4 tons/square foot
4Bw horizon = 0.5 to 1 tons/square foot
4C1 horizon = 1.5 to 2.5 tons/square foot
5C2 horizon = 0.4 to 1 tons/square foot
6A horizon = 0.2 to 0.5 tons/square foot
6Bw horizon = 1 to 1.5 tons/square foot
6C1 horizon = 0..5 to 1 tons/square foot
6C2 horizon = 0..5 to 1 tons/square foot
6C3 horizon = 0..5 to 1 tons/square foot
7C4 horizon = reticulite not measured
8C5 horizon = 1.5 to 2 tons/square foot
National Cooperative Soil Survey
U.S.A.