The Mureung series are members of the fine, mixed, thermic family of Typic Paleudalfs [Cutanic Luvisols (Profondic Siltic Chromic) classified by WRB]. These soils have dark yellowish brown silt loam Ap horizons, dark yellowish brown silty clay BA horizons, dark yellowish brown silty clay Bt1 horizons, strong brown silty clay Bt2 horizons, and strong brown silty clay Bt3 horizons with red mottles. They occur on coastal lava plains derived from pyroclastic materials.

Typifying Pedon: Mureung silty clay loam-garlic (Colors are for moist soil).

  Slope: 2-7%

  Elevation: 22 m above m.s.l.

  Soil moisture regime: Udic

  Soil temperature regime: Thermic

  Parent material: Pyroclastic materials

  Diagnostic features: An ochric epipedon from a depth of 0 to 12 cm and an argillic horizon from a depth of 42 to 180 cm (An argic horizon from a depth of 42 to 180 cm by WRB).

  Described by: Song, K. C., D. C. Noh, and S. J. Jung,  7 Sep., 2006.

Ap - 0 to 12 cm. Dark yellowish brown (10YR 4/4) silt loam; moderate medium subangular blocky structure; friable, sticky and plastic; few fine roots; few very fine pores; abrupt smooth boundary.

BA - 12 to 42 cm. Yellowish brown (10YR 5/4) silt loam; weak medium subangular blocky structure; friable, slightly sticky and plastic; few very fine roots; common fine pores; abrupt smooth boundary.

Bt1 - 42 to 65 cm. Dark yellowish brown (10YR 4/6) silty clay; moderate coarse angular blocky structure; slightly firm, very sticky and very plastic; thin continuous clay cutans; few very fine roots; common fine pores; few worm holes; gradual smooth boundary.

Bt2 - 65 to 100 cm. Strong brown (10YR 5/8) silty clay; moderate coarse prismatic structure; slightly firm, very sticky and very plastic; thick continuous clay cutans; no roots; common fine pores; few medium Mn concretions; clear smooth boundary.

Bt3 - 100 to 180 cm. Strong brown (7.5YR 5/6) silty clay; moderate coarse angular blocky structure; common medium to coarse prominent red (2.5YR 5/6) mottles; firm, very sticky and very plastic; thick continuous clay cutans through worm holes; few fine pores; common coarse Mn concretions; severely weathered basaltic gravels and cobbles

  The typifying pedon has an ochric epipedon from a depth of 0 to 12 cm and an argillic horizon from a depth of 42 to 180 cm. It has a base saturation (by sum of cations) of 35% or more at 125 cm below the upper boundary of the argillic horizon. That can be classified as Alfisol. It has udic soil moisture regime, and can be classified as Udalf. It does not have a densic, lithic, or paralithic contact within 150 cm of the mineral soil surface, does not clay decrease with increasing depth of 20% or more from the maximum clay content within 150 cm of the mineral soil surface, and has an argillic horizon with in 50% or more of the matrix of one or more subhorizons in its lower one-half, hue of 7.5YR or redder and chroma of 5 or more. It can be classified as Paleudalf. Also it meets the requirements of Typic Paleudalf.

  The typifying pedon has more than 35% clay at the particle-size control section and has thermic soil temperature regime. Therefore it can be classified as fine, mixed, thermic family of Typic Paleudalf.

Type Location: About 50 meters north-west of the Office of Gosanbaengdeui Agricultural Association, Gosan Ri, Hangyeong Myeon, Jeju city, Jeju Do (126° 11' 23.7'', 33° 17' 34.4'').

Range in Characteristics: These soils have ochric epipedons and argillic horizons. The solum thickness ranges from 150 to 200 cm and depth to hard rock is more than 3 meters. Base saturation is more than 35 percent. Soil reaction ranges from strongly to medium acid. Ap horizons are brown or dark yellowish brown silt loam to silty clay loam. Argillic B horizons are strong brown, dark yellowish brown, or yellowish brown silty clay loam, silty clay, or clay.

Competing Series and Their Differentiae: These are the Susan, Gangjeong, and Donghong soils. The Susan soils occur on cinder cones. The Gangjeong soils are Mollic Subgroups and moderately well drained. The Donghong soils are Mollic Subgroups and occur on lava plains around cinder cones.

Setting: The Mureung soils occur on nearly level to sloping coastal lava plains and are derived from pyroclastic materials. Slopes range form 0 to 15 percent and dominant slopes are 2 to 7 percent.

Principal Associated Soils: The Daejeong, Gangjeong soils are associated in lower positions. The Yeongrag soils occur on similar physiographic positions.

Drainage and Permeability: Well drained. Runoff is slow, and permeability is very slow.

Use and Vegetation: Most of these soils are used for cultivated upland crops such as garlic, barley, and potato. 

Distribution and Extent: The Mureung soils are of moderate extent in low elevated lava plains in the northwestern parts of Jeju Do.

Series Established: Seogwipo city, Jeju Do, 1975. Revised, Jeju city, Jeju Do, 2006.

Laboratory data sheets of typifying pedon.