The Songsan series are members of the coarse loamy, mixed, mesic family of Typic Dystrudepts [Haplic Cambisols (Eutric) classified by WRB]. These soils have brown gravelly sandy loam A horizons, brown gravelly sandy loam BA horizons, brown gravelly sandy loam Bw horizons, and brown gravelly sandy loam C horizons. They are developed in mountainous areas in residuum derived from metamorphic rocks such as biotite, granite-gneiss and schist.

Typifying Pedon: Songsan gravelly sandy loam-pine forest (Colors are for moist soil).

  Slope: 30-60%

  Elevation: 200 m above m.s.l.

  Soil moisture regime: Udic

  Soil temperature regime: Mesic

  Parent material: Residium on granite

  Diagnostic features: An ochric epipedon from a depth of 0 to 20 cm and a cambic horizon from a depth of 44 to 82 cm (A cambic horizon from a depth of 44 to 82 cm by WRB).

  Described by: Song, K. C., D. C. Noh, and B. K. Hyun,  7 October, 2013.

Morphological properties of typifying pedon.

A  - 0 to 20 cm. Brown (7.5YR 4/3) gravelly sandy loam; weak medium to coarse granular structure; friable, slightly sticky and slightly plastic; many fine to medium roots; common fine pores; few fine micas; few worm holes; 25% gravels; clear wavy boundary.

BA - 20 to 44 cm. Brown (7.5YR 4/3) gravelly sandy loam; weak fine to medium subangular blocky structure; friable, slightly sticky and slightly plastic; common fine to medium roots; common fine pores; few fine micas; few worm holes; 20% gravels and cobbles; gradual wavy boundary.

Bw - 44 to 82 cm. Brown (7.5YR 4/3) gravelly sandy loam; weak medium subangular blocky structure; friable, slightly sticky and slightly plastic; common fine to medium roots; common fine to medium pores; few fine micas; few worm holes; 25% gravels and cobbles; clear wavy boundary.

C - 82 to 160 cm. Brown (7.5YR 5/4) gravelly sandy loam; structureless, massive; slightly sticky and slightly plastic; few fine roots; few medium pores; few fine micas; 30% gravels and cobbles.

  The typifying pedon has an ochric epipedon from a depth of 0 to 20 cm and a cambic horizon from a depth of 44 to 82 cm. That can be classified as Inceptisol. It has an udic soil moisture regime and keys out as Udept. Also it meets the requirements of Typic Dystrudept. The typifying pedon has, in the fraction less than in diameter, 15% or more particles with diameters of 0.1 to 75 mm and, in the fine-earth fraction, less than 18% clay at the particle-size control section and mesic soil temperature regime. Therefore it can be classified as coarse loamy, mixed, mesic family of Typic Dystrudept.

Type Location: The entrance of the Yeonhwasan Boriwon, Haegog Dong, Cheoin Gu, Yongin city, Gyeonggi Do (127° 16' 45.9'',  37° 11' 21.4'').

Range in Characteristics: These soils have ochric epipedons and cambic horizons. Depth to hard rock is more than 2 meters, generally ranging from 2 to 5 meters or more. Base saturation is commonly less than 60 percent. Reaction is strongly to medium acid. A horizons are brown or dark yellowish brown fine gravelly sandy loam or coarse sandy loam. The cambic B horizons are yellowish brown, light yellowish brown, light brown, reddish yellow, or strong brown gravelly sandy loam or coarse sandy loam. C horizons are yellowish brown, pale brown, or light yellowish brown gravelly coarse sandy loam or loamy coarse sand. 

Competing Series and Their Differentiae: These are the Osan, Isan and Daesan series. The Osan soils have redder color. The Isan soils are derived from conglomerate rocks. The Daesan soils are derived from phyllite or schist of Ogcheon system.

Setting: The Songsan soils occur on mountainous areas of granite-gneiss and schist. Slopes range from 15 to 100 percent but 30 to 60 percent slopes are dominant.

Principal Associated Soils: The Cheongsan and Osan soils are associated with the Songsan soils on similar parent materials. The Samgag soils are associated with similar physiographic position which contracts between granite and granite-gneiss or schist areas.

Drainage and Permeability: Somewhat excessively drained. Permeability is moderately rapid.  When the soil is saturate, the runoff is rapid or very rapid depending on the slopes.

Use and Vegetation: Most of these soils are used for forest.

Distribution: The Songsan soils are of large extent and are distributed in western and southern parts of the country.

Series Established: Hwaseong Gun, Gyeonggi Do, 1972. Reviced, Yongin city, Gyeonggi Do, 2013.

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) - - - - - - - - - - -
0-20	A	20.8	31.3	47.9			16.9	12.4	4.0	8.7	10.1	14.2	10.9
20-44	BA	16.1	17.8	66.1			8.6	9.2	5.3	13.8	18.1	20.6	8.3
44-82	Bw	16.0	18.3	65.6			7.9	10.4	5.5	13.1	16.8	20.8	9.5
82-160	C	15.5	21.1	63.4			8.8	12.3	5.1	13.4	15.5	18.9	10.5

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

0-20

1.47

20-44

0.21

44-82

0.11

82-160

0.22

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

0-20

0.55

20-44

0.57

44-82

0.58

82-160

0.56

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
0-20	2.2	1.2	0.6	0	4.0	10.2	4.3	14.2	11.5	8.3	52.0
20-44	2.9	2.4	0.4	0.1	5.7	5.6	1.9	11.0	9.1	7.6	24.8
44-82	2.4	2.4	0.6	0.1	5.4	5.6	2.9	11.3	9.3	8.4	34.9
82-160	3.0	1.7	0.5	0.1	5.3	4.3	0.6	9.6	8.7	5.9	10.4

Depth (cm)

(Base Sat)

CO3 as

Res

Cond

(------ pH ------)

Acid Oxalate Extraction

Sum

NH4-

CaCO3

NaF

KCl

CaCl2

H2O

Opt

Al

Fe

Si

OAc

˂2mm

.01M

Den

5C3

5C1

6E1g

8E1

8I

8C1d

8C1f

8C1f

8J

6G12

6C9a

6V2

---- Pct ----

ohms/cm

dS/m

1: 1

1: 2

1: 1

- Pct of ˂2mm -

0-20

28.0

34.6

3.9

4.4

5.3

20-44

50.4

62.7

3.6

4.5

5.4

44-82

49.1

58.5

3.6

4.4

5.4

82-160

55.1

61.0

4.1

4.9

5.8