DOJEON SERIES

Established Series PCS, JYH 10 Nov., 1979

  The Dojeon series are members of the fine loamy, mixed, mesic family of Typic Hapludults [Cutanic Alisols (Alumic Hyperdystric) classified by WRB]. These soils have brown gravelly silt loam Ap horizons, yellowish brown gravelly clay loam BA horizons, brown gravelly clay loam Bt1 horizons, brown gravelly clay loam Bt2 horizons, and yellowish brown gravelly clay loam Bt3 horizons. These soils are on mountain foot slopes and formed in colluvium from limestones.

Typifying Pedon: Dojeon gravelly loam-sesame (Colors are for moist soil).

  Slope: 7-15%

  Elevation: 212 m above m.s.l.

  Soil moisture regime: Udic

  Soil temperature regime: Mesic

  Parent material: Colluvium from limestone

  Diagnostic features: An ochric epipedon from a depth of 0 to 10 cm and an argillic horizon from a depth of 25 to 145 cm (An argic horizon from a depth of 25 to 145 cm by WRB).

  Described by: Song, K. C., D. C. Noh, and S. J. Jung,  14 Oct., 2010.

Morphological properties of typifying pedon.

Ap - 0 to 10 cm. Brown (10YR 4/3) gravelly silt loam; moderate medium to coarse granular structure; friable, slightly sticky and plastic; common very fine to medium roots; few medium pores; few worm holes; 20% gravels; clear wavy boundary.

BA - 10 to 25 cm. Yellowish brown (10YR 5/4) gravelly clay loam; moderate fine to medium subangular blocky structure; friable, sticky and plastic; thick patch clay cutans; few very fine to fine roots; common medium to coarse pores; few worm holes; 30% gravels; clear wavy boundary.

Bt1 - 25 to 62 cm. Brown (10YR 5/3) gravelly clay loam; moderate fine to medium subangular blocky structure; friable, sticky and plastic; thin continuous clay cutans; few very fine roots; common medium to coarse pores; few worm holes; 30% gravels; clear wavy boundary.

Bt2 - 62 to 91 cm. Brown (10YR 4/3) gravelly clay loam; moderate medium subangular blocky structure; friable, sticky and plastic; thin continuous clay cutans; few very fine roots; many fine to medium pores; few worm holes; 25% gravels; clear wavy boundary.

Bt3 - 91 to 145 cm. Yellowish brown (10YR 5/6) gravelly clay loam; moderate fine to medium subangular blocky structure; friable, very sticky and very plastic; thick patch clay cutans; no roots; common medium to coarse pores; 25% gravels.

  The typifying pedon has an ochric epipedon from a depth of 0 to 10 cm and an argillic horizon from a depth of 25 to 145 cm. It has a base saturation (by sum of cations) of less than 35% at 125 cm below the upper boundary of the argillic horizon. That can be classified as Ultisol. It has an udic soil moisture regime, and can be classified as Udult. Also it meets the requirements of Typic Hapludult.

  The typifying pedon has in the fraction less than 75 mm in diameter, 15% or more particles with diameters of 0.1 to 75 mm and in the fine-earth fraction, 18 to 35% clay at the particle-size control section and has mesic soil temperature regime. Therefore it can be classified as fine loamy, mixed, mesic family of Typic Hapludult.

Type Location: About 250 meters S-oil Oline Station, Sapyeong Ri, Gagog Myeon, Danyang Gun, Chungcheongbug Do (128° 23' 59.4'', 37° 02' 2.4'').

Range in Characteristics: These soils have ochric epipedons and argillic horizons. The solum thickness ranges from 100 to 150 cm and depth to hard rock is more than 2 meters. Reaction is strongly to slightly acid. Base saturation is less than 60 percent. These soils have 10 to 35 percent gravels and cobbles. These soils have brown or dark yellowish brown Ap horizons; brown, dark yellowish brown, brownish yellow, yellowish brown, or light yellowish brown gravelly clay loam Bt horizons.

Competing Series and Their Differentiae: These are the Anryong, Bongsan, and Asan soils. The Anryong soils are derived from acidic colluvial materials. The Bongsan soils occur on rolling to hilly areas and are derived from porphyry materials. The Asan soils occur on rolling to hilly areas and are derived from granite gneiss, micaceous schist, and similar materials.

Setting: The Dojeon soils are on mountain foot slopes and formed in colluvium from limestones.  The slope ranges from 2 to 30 percent.

Principal Associated Soils: These are the Mosan and Pyeongchang in residuum from limestones, the Maji and Pyeongjeon soils in lower positions.

Drainage and Permeability: Well drained; moderate or moderately slow permeability; medium  runoff.

Use and Vegetation: Used for upland crops.

Distribution and Extent: The Dojeon soils occur in colluvium from limestones throughout the country. These soils are inextensive.

Series Established: Danyang Gun, Chungcheongbug Do, 1978. Revised, Danyang Gun, Chungcheongbug Do, 2010.

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) - - - - - - - - - - -
0-10	Ap	19.9	49.2	30.9			29.3	19.9	3.0	6.9	6.6	8.2	6.3
10-25	BA	20.5	51.6	28.0			29.5	22.2	3.0	6.7	6.5	7.6	4.2
25-62	Bt1	27.5	33.1	39.4			13.0	20.1	3.8	8.3	10.6	9.8	6.8
62-91	Bt2	27.6	33.9	38.5			11.0	22.9	3.1	7.6	7.5	10.5	9.8
91-145	Bt3	29.3	35.1	35.6			11.5	23.6	2.8	6.7	7.4	10.2	8.6

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

0-10

1.73

10-25

0.92

25-62

0.53

62-91

0.51

91-145

0.34

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

0-10

0.64

10-25

0.54

25-62

0.46

62-91

0.41

91-145

0.38

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
0-10	5.7	1.3	0.4	0.1	7.4	8.9	0	16.4	12.8	7.4	0
10-25	3.9	1.1	0.3	0	5.4	8.4	0.4	13.8	11.0	5.8	7.4
25-62	1.6	0.5	0.2	0	2.2	14.1	2.1	16.3	12.6	4.4	48.8
62-91	1.4	0.4	0.1	0	1.9	12.9	2.4	14.8	11.3	4.3	55.2
91-145	2.3	0.3	0.2	0	3.0	9.9	0.7	12.9	11.0	3.7	19.6

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 -
0-10	45.5	58.2					5.0	5.5	6.1
10-25	38.8	48.6					4.3	5.0	5.7
25-62	13.7	17.8					3.8	4.2	5.1
62-91	13.0	17.0					3.8	4.2	5.1
91-145	23.2	27.2					4.1	4.7	5.6