The Sineom series are members of the medial, ferrihydritic, thermic family of Acrudoxic Melanudands [Leptic Melanic Aluandic Andosols (Acroxic Siltic) classified by WRB]. These soils have black silt loam A horizons, black silt loam AB horizons, and dark yellowish brown silt loam Bw horizons underlain by consolidated basaltic hard rock. These soils are developed on lava plains derived from pyroclastic materials.

Typifying Pedon: Sineom silt loam-wild grass (Colors are for moist soil).

  Slope: 2-7%

  Elevation: 278 m above m.s.l.

  Soil moisture regime: Udic

  Soil temperature regime: Thermic

  Parent material: Pyroclastic materials

  Diagnostic features: A melanic epipedon from a depth of 0 to 42 cm, a cambic horizon from a depth of 42 to 58 cm, and an andic soil properties from a depth of 0 to 58 cm (A melanic horizon from a depth of 0 to 42 cm, a cambic horizon from a depth of 42 to 58 cm, and an andic properties from a depth of 0 to 58 cm by WRB).

  Described by: Song, K. C., D. C. Noh, and S. J. Jung,  14 June, 2011.

Morphological properties of typifying pedon.

A - 0 to 15 cm. Black (10YR 2/1) silt loam; weak fine to medium granular structure; friable, slightly sticky and slightly plastic; many fine to medium roots; few fine pores; clear smooth boundary.

AB - 15 to 42 cm. Black (10YR 2/1) silt loam; weak fine to medium subangular blocky structure; firm, slightly sticky and slightly plastic; common fine to medium roots; few fine pores; clear smooth boundary.

Bw - 42 to 58 cm. Dark yellowish brown (10YR 4/4) silt loam; weak fine to medium subangular blocky structure; firm, sticky and plastic; common fine to medium roots; common fine pores.

R – 58 cm+ Dark colored hard basalt rock.

  The typifying pedon contains 4.4-5.7% oxalate extractable (Al + 1/2 Fe), over 85% phosphate retention, and lower bulk density than 0.90 g/m³ from the depth of 0 to 200 cm. It has andic soil properties and keys out as Andisol. The typifying pedon has an udic soil moisture regime and can be classified as Udand. A and AB horizons (0-42 cm) have a color value, moist, and chroma of 2 or less, melanic index of 1.70 or less, and 6% or more organic carbon. That meets the requirements of melanic epipedon. That keys out as Melanudand. It has a sum of extractable bases (by NH₄OAc) plus 1N KCl-extractable Al totaling less than 2.0 cmol (+)/kg in the fine-earth fraction of one or more horizons with a total thickness of 30 cm or more at a depth between 25 and 100 cm from the mineral soil surface. That can be classified as Acrudoxic Melanudand.

  The typifying pedon has a fine-earth fraction that has a water content at 1,500 kPa tension of 12% or more on air-dried samples and has less than 35% (by volume) rock fragments. Thus, the substitute for particle-size class is medial. It has a sum of 8 times the Si (percent by weight extracted by ammonium oxalate from the fine-earth fraction) plus 2 times the Fe (percent by weight extracted by ammonium oxalate from the fine-earth fraction) of 5 or more, and 8 times the Si is less than 2 times the Fe. It has ferrihydritic mineralogy class and thermic soil temperature class. Therefore it can be classified as medial, ferrihydritic, thermic family of Acrudoxic Melanudand.

Type Location: About 100 meters south-east of the Ajin Garden, Songdang Ri, Gujwa Eub, Jeju city, Jeju Do (126° 44' 39.0'', 33° 25' 57.8'').

Range in Characteristics: These soils have melanic epipedons, cambic horizons, and andic soil properties. Depth to hard rock is 50 to 100 cm. Reaction is strongly acid. Base saturation is less than 50 percent. A horizons are very dark brown or black silt loam. Bw horizons are very dark brown, very dark grayish brown, or black silt loam underlain by basaltic hard rocks.

Competing Series and Their Differentiae: These are the Namwon, Wimi, and Minag soils. The Namwon soils are deeper in soil depth. The Wimi soils have 10 to 35% gravels in the profiles. The Minag soils have stones and boulders.

Setting: The Sineom soils are developed on lava plains and are derived from pyroclastic materials. Slope ranges from 2 to 15 percent, and 2 to 7 percent slopes are dominant.

Principal Associated Soils: The Gimnyeong, Haengwon, Wimi, Minag, Topyeong, and Namwon soils are associated with the Sineom soils. They occur on similar physiographic positions.

Drainage and Permeability: Well drained, permeability is rapid, and runoff is medium.

Use and Vegetation: Most of these soils are used for grass land and small areas are used for cultivated upland crops such as barley and sweet potato.

Distribution and Extent: The Sineom soils are of small extent and are distributed on lava plains of Jeju Do.

Series Established: Seogwipo city, Jeju Do, 1975. Revised, Jeju city, Jeju Do, 2011.

Laboratory data sheets of typifying pedon.

Depth (cm)	Horizon	( --- Total ---)			(-- Clay --)		(-- Silt --)		(------- Sand -------)
		Clay	Silt	Sand	Fine	Coarse	Fine	Coarse	VF	F	M	C	VC
		LT	.002	.05	LT	LT	.002	.02	.05	.10	.25	.5	1
		.002	- .05	- 2	.0002	.002	- .02	- .05	- .10	- .25	- .50	- 1	- 2
		- - - - - - - - - - - Pct of ˂ 2mm (3A1) - - - - - - - - - - -
0-15	A	24.9	71.5	3.6			41.4	30.1	1.0	0.8	0.5	0.7	0.5
15-42	BA	22.5	63.0	14.5			32.1	30.9	4.9	5.9	3.0	1.3	0.5
42-58	Bw	15.6	60.7	23.7			27.5	33.2	8.9	10.6	3.3	0.8	0.2
58-	R

Depth (cm)

Coarse Fractions(mm)

˃2mm

Orgn

Total

Extr

Total

(-- Dith -Cit --)

Weight

Wt

C

N

P

S

Extractable

2-5

5-20

20-75

.1-75

Pct of

Fe

Al

Mn

Whole

6A1c

6B3a

6S3

6R3a

6C2b

6G7a

6D2a

Pct of ˂ 75mm (3B1)

Soil

Pct ˂ 2mm

g/kg

Pct of ˂ 2mm

0-15

11.72

15-42

12.66

42-58

3.51

58-

Depth (cm)

Ratio/Clay

Atterberg

( Bulk Density )

COLE

(- Water Content -)

WRD

CEC

1500

Limits

Field

33

Oven

Whole

Field

10

33

1500

Whole

kPa

LL

PI

Moist

kPa

Dry

Soil

Moist

kPa

kPa

kPa

Soil

8D1

8D1

4P1

4P

4A3a

4A1d

4A1h

4D1

4B4

4B1c

4B1c

4B2a

4C1

Pct ˂0.4mm

- - g/cc - -

cm/cm

-- Pct of ˂2mm --

cm/cm

0-15

2.29

0.45

147.0

15-42

2.42

0.57

113.0

42-58

2.02

0.38

134.7

58-

Depth (cm)	( NH4OAc Extractable Bases )					Acid-	Extr	(----- CEC -----)			Al
	Ca	Mg	K	Na	Sum	ity	Al	Sum	NH4-	Bases	Sat
	5B5a	5B5a	5B5a	5B5a	Bases			Cats	OAc	+ Al
	6N2e	6O2d	6Q2b	6P2b		6H5a	6G9a	5A3a	5A8b	5A3b	5G1
	- - - - - - - - - - - - meq / 100g - - - - - - - - - - - -										Pct
0-15	1.2	0.6	0.3	0.2	2.3	86.6	0.1	88.9	57.0	2.4	4.2
15-42	0.1	0.1	0.1	0.1	0.5	76.5	0.5	77.0	54.5	1.0	50.0
42-58	0.2	0.1	0.1	0.1	0.5	41.6	0	42.1	31.5	0.5	0
58-

Depth (cm)	(Base Sat)		CO3 as	Melanic	P Ret	(------ pH ------)				Acid Oxalate Extraction
	Sum	NH4-	CaCO3	Index		NaF	KCl	CaCl2	H2O	Opt	Al	Fe	Si
		OAc	˂2mm					.01M		Den
	5C3	5C1	6E1g			8C1d		8C1f	8C1f	8J	6G12	6C9a	6V2
	---- Pct ----				Pct		1: 1	1: 2	1: 1		- Pct of ˂2mm -
0-15	2.6	4.1			98.8		4.3	4.5	5.2		3.25	2.76	0.26
15-42	0.7	0.9			99.7		4.5	4.6	5.1		4.17	3.02	0.52
42-58	1.2	1.6			98.8		4.9	4.9	5.3		2.94	2.93	0.63
58-